Samuel Graff

Serum phosphatase relations in mother and fetus.

Abstract Profound alterations in the bodys economy of calcium and phosphate occur during pregnancy and lactation, to provide for the fetal needs for these substances and for their excretion by the mammary glands. Studies in placental permeability employing tracer doses of radioactive phosphorus have shown, for example, that the guinea pig fetus near term retains in each hour as much phosphorus as the total quantity of this element in the circulating plasma of its mother. 27 Changes in inorganic phosphate as well as calcium in the serum of the pregnant woman are so slight, however, that they are practically completely lacking in significance for the interpretation of metabolic phenomena. Maternal stores are obviously essential to the growth of the fetus. These stores of phosphorus exist in the form of organic esters, the phosphate ions being liberated as needed through the mediation of enzymes, notably alkaline phosphatase. This enzyme, widely distributed in the body, occurs in particularly high concentration in bone and cartilage, where it presumably plays an essential part in the process of ossification by producing an excess concentration of phosphate ions which leads in turn to the precipitation of calcium phosphate. The enzyme is present also in the blood serum, where it can be measured by a variety of techniques. Its activity is expressed in arbitrary units, dependent upon the type of substrate employed in the determination. When glycerophosphate is used (Bodansky method) the range of normal for adults is 1.5 to 4.0 units per 100 c.c. of serum. In children the phosphatase activity is increased, ranging between 5 to 12 units per 100 c.c. The enzyme concentration is also elevated in some diseases of the liver, especially those with obstructive jaundice, and in many types of bone disease including rickets, osteomalacia, osteitis fibrosa cystica, and osteitis deformans. 24 The behavior of alkaline phosphatase in relation to the various phases of reproduction is interesting because of the need for mobilization of phosphorus which the reproductive cycle imposes. This study is divided into four parts: pregnancy, puerperium, lactation, and fetal-maternal relations.

Nutrition and premature labor.

Abstract 1. 1. The literature dealing with the relation of maternal nutrition to premature labor has been reviewed. Despite the prevailing view that nutritional inadequacy is a common cause of premature labor, the evidence for this is not convincing. 2. 2. Dietary histories of a group of patients who had premature labors revealed no significant differences from those of a control group with full-term pregnancies in calculated intake of the various food essentials. 3. 3. Hematological and blood biochemical determinations in the early puerperium also failed to reveal any significant differences between the premature parturients and their full-term controls. Determinations included serum proteins, serum amino acid nitrogen, red cell volume, hemoglobin, serum alkaline phosphatase, serum vitamin A, serum carotene, serum ascorbic acid, and whole blood ascorbic acid. 4. 4. This study offers no support to the theory that nutritional deficiency is a common cause of premature labor.

The relationship of disorders of the blood-clotting mechanism to toxemia of pregnancy and the value of heparin in therapy

T HIRTY years ago, Abderhaldenl introduced in his “abwehrfermente” theory the concept that protective ferments developed in the serum of the mother in response to the invasive action of t,he placenta. Although there were a number of reports both in favor of and against this theory, the consensus at that time agreed with Van Slyke44 that, nearly all human serum could digest coagulated protein at least to some extent, when it wa,s incubated with placental tissue as advised by Abderhaltlen, and that t,he test was not specific for pregnancy.

Effect of Protein Extracts of Neural Plate Plus Chordamesoderm on Presumptive Epidermis.

Summary Protein extracts of the neural plate plus underlying chordamesoderm induce the presumptive epidermis of the gastrula to form neural tubes. However no differences were obtained in the structure of the neural tubes which were induced by extracts of anterior as compared with posterior regions of the neural plate and underlying chordamesoderm. Preparations of the anterior and posterior regions of the neural plate and underlying chordamesoderm which were killed by freezing and subsequent drying induced neural tubes in the explanted presumptive epidermis of the gastrula. Quantitative differences in the frequency of induction were obtained with the posterior neural plate and underlying chordamesoderm inducing with the greatest frequency.

A study of serum trypsin inhibitor in pregnancy

Abstract The facts and arguments suggesting the possible role of blood coagulative or fibrinolytic enzyme systems in the toxemias of pregnancy were assembled in an earlier publication from this laboratory. 3 It was also shown in that article that the interesting speculation by Schneider that toxemia of pregnancy was the result of placental thromboplastin entering the maternal circulation could not be supported by therapeutic tests. This article describes experiments which were devised to examine the possible role of the fibrinolysin enzyme system in pregnancy.

Blood Volume in Normal Chicks and in Chicks with Nutritional Encephalomalacia

Conclusions 1. The disease described as nutritional encephalomalacia of chicks is not associated with significant alterations in cell plasma ratio, plasma or blood volume. 2. During the early growth period of the chick, the growth of the plasma and blood follow closely the growth of body weight. The blood and plasma volume per kilo, aside from individual variations, remain constant throughout the early growth period.

Some aspects of tricarboxylic acid cycle metabolism in the central nervous system.

THE central nervous system is delineated by certain biochemical characteristics that reflect its unique function. The system, representing but 2% of the total body weight of the mammalian organism, is nonetheless responsible for 20% of the basal metabolism, 25% of the total oxygen consumption, and 15 to 20% of the total cardiac output.1 Under normal conditions, glucose forms the main oxidizable substrate of the central nervous system.Fatty acids and acetate are oxidized only slightly, whether in vivo or in ~itr0.2.5.6 Glutamine is the only other major carbon source demonstrated to enter the intact central nervous system, al. though in insufficient amounts for energy requirements.? Further, there is little evidence of an active hexose monophosphate pathway in the central nervous system,8 nor is there evidence of metabolic response to any hormonal substance. The relatively low levels of carbohydrate reserves, that is, glycogen, cannot long maintain the normal metabolic activity of neural tissue. The chief energy source for the central nervous system is therefore blood glucose, which is degraded to pyruvate by the glycolytic pathway and to carbon dioxide and water by the tricarboxylic acid (TCA) cycle. Pyruvate can enter the TCA cycle in either of 2 distinct routes, by oxidative decarboxylation to acetyl coenzyme A (CoA) or by condensation with carbon dioxide to form a dicarboxylic acid. Pyruvate entering the TCA cycle as acetyl-CoA is coupIed to the synthesis of high energy phosphate but does not produce a net gain in dicarboxylic acids. Alternatively, formation of dicarboxylic acids by carbon dioxide fixation results in a net increase in the mass of TCA cycle intermediates, that is, synthetic intermediates are formed, but there is no direct formation of high energy phosphates. The TCA cycle of the central nervous system has been studied by administratiqn of labeled pyruvate or, more precisely, its metabolic equivalent, DL-alanine-2C14, to rats and determination of the relative radioactivity of the individual carbon atoms of L-glutamate, (equivalent to alpha-ketoglutamic acid of the TCA cycle), isolated from central nervous system tissues.