Placenta composition

To appreciate the role of laboratory tests in pregnancy health care, it is necessary to understand fundamental topics, such as conception, embryo development, fetal growth, the role of the placenta, the importance and composition of amniotic fluid, maternal adaptation to pregnancy, and functional maturation of the fetus. 

Phospholipid composition of microsomes from normal and diseased placenta. /. Steroid Biochem. 18, 309-312 (1983). 

Figure 5,8, CsCI profiles of compositional DNA fractions from human placenta, B mouse liver and C chicken erythrocyte, as obtained from preparative centrifugation in CS2SO4/BAMD density gradient. The rf (ligand/tiueleotide molar ratio) values used were 0.12 for mouse and 0.14 for human and chicken. Modal buoyant densities and relative amounts of the fractions arc indicated. P indicates the pellet. Notice the satellite peak (centered at abt>ut 1.700 g/ml) in the last fractions of human, and the satellite peak (1.691-1.692 g/cm ) in mouse DNA fractions i-4. A , B and C display autoradiograms of terminally labelled (Cooper et al.. 1983 1.2% agarose gels were used) Hpa 11 fragments from DNA fractions. (From Aissani...

Thrombin was discovered by Buchanan in 1835. This enzyme, or rather one of the constituent parts of this enzyme, is found in abundance in the white corpuscles of the blood. It is also found in the red corpuscles, though in much smaller proportion, and in many tissues. It exists in the lymph, which has approximately the same composition as blood, and in pus, which is a sort of serum in which float the white corpuscles that have undergone fatty degeneration. Much discovered the presence of thrombin in staphylococcus aureus, and Higuchi has, by the aid of physiological salt solution, isolated this enzyme from the soft mass of the placenta. 

Poly(ADP-ribose) synthetases were purified to apparent homogeneity from calf thymus, mouse testis, and human placenta. The major characteristics of these enzymes are presented in Table 1. In addition to molecular mass, sedimentation constant, isoelectric point, and partial specific volume, the apparent for NAD and DNA as well as V ,ax of the reaction are all common to these three enzymes. Amino acid compositions of the enzymes are shown in Table 2. Here again, the numbers of each amino acid residue are very similar to each other, although some differences as denoted by star symbols are noted. 

PuriHcation of poly(ADP-ribose) polymerase from human placenta and amino acid sequences of a-chymotryptic peptides. The purMcation of the poly(ADP-ribose) polymerase from two placentas (500-600 g) was carried out in two days yielding 100-200 pg purified enzyme with 10% recovery a 3,500-fold purification was achieved using the procedure of Burtscher et al. (2) with a slight modification (3). The purified enzyme revealed a single band at the position corresponding to a molecular weight of 116 kDa (Fig. 1). The amino acid composition of the human placental poly(ADP-ribose) polymerase was very similar to that reported by Ushiro etal. (4). 

Fatty Acid Composition of Sphingomyelins in Blood, Spleen, Placenta, Liver, Lung, and Kidney Biochim. Biophys. Acta 125(1) 60-69 (1966) CA 65 5731f... 

Table 1. Lipid content and fatty acid composition of the maternal and fetal plasmas and of the placenta.

On the other hand, the above hypothesis does not explain how edema or albuminuria can occur before the blood pressure is raised. There nuiy be cases, however, in which the ischemia of the placenta or a possible infarct is not extensive enough to raise the maternal blood pressure immediately. Such can be expected when there is an ample supply of vessels initially. There may be pathological changes already in the composition of the blood, however. The changes in the serum protein pattern, for instance, may cause a greater inclination to develop edema, and the hormonal conditions in pregnancy also increase this tendency. 

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