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The relation between the mechanical properties and the lamellar morphology of the α-isotactic polypropylene transcrystalline interphase in a fiber composite was investigated by means of nanometric shear and directional indentation measurements, using scanning force microscopy. Measurements were performed along directions parallel and perpendicular to the transcrystalline growth direction. A key finding is the inversion of the shear modulus anisotropy ratio from 2.3 to 0.5 as the crystal grows away from the fiber. On the basis of this finding, an improved view of the hierarchical lamellar and molecular order of the transcrystalline layer is proposed.

The ability to diagnose severe chronic fetal distress-impending death utilizing the six different definitions of decreased fetal movement (DFM) currently in use, was evaluated retrospectively in 616 high-risk pregnant women. The study reveals the superiority of two definitions as prognostic tools: The “movements alarm signal” (MAS), i.e. no fetal movements (FM) for at least 12 hours with audible fetal heart beats, and “ten and less FM” (≤ 10 FM), i.e. ten or fewer FM in 12 hours. The application of these definitions distinguished two groups of patients which included significantly more poor outcomes than were contained by the groups of patients based on the other definitions. MAS was the definition also selecting the group with fewest false-positive cases. The monitoring of FM while utilizing one of the above two definitions of DFM as cut-off points for suspected impending fetal death is a useful adjunct in high-risk pregnancy management.

The directional Young's modulus of transcrystalline isotactic polypropylene grown from the surface of high modulus carbon fibers has been measured by two types of Knoop microindentation experiments. First, static indentation tests were performed and a new data reduction procedure was used to translate the Knoop hardness data into modulus values. The technique assumes that the extent of elastic recovery of a Knoop indent is linearly related to the modulus-to-hardness ratio. The Knoop tip is sensitive to material anisotropy, which allows us to generate data for the different lamellar directions. The hardness and Young's modulus of the transcrystalline layer are found to be higher by up to 30% when the longer diagonal of the probing Knoop tip is perpendicular to the transcrystalline growth direction. Second, continuous indentation tests are performed and a different data reduction technique is used, which leads to similar results. The microindentation approach used here is found to be particularly advantageous for the assessment of Young's modulus of small-scale polymeric regions or when only small polymeric specimens are available.

Summary Fetal movements were assessed in 7 cases of systemic lupus erythematosus (SLE). The daily fetal movement count was lower than normal in 4 cases. Three patients with renal disease and raised blood pressure had decreased fetal movements until cessation and poor fetal outcome. Uncomplicated cases of SLE did not manifest cessation of fetal movement, and their fetal outcome was favorable. When a decrease in fetal movements becomes apparent and the condition is verified by other biophysical tests, the patient should be delivered provided the fetus is viable.

This study was undertaken in order to evaluate pregnancy outcome in three groups of triplet conceptions. Of 36 delivered triplet gestations, seven were spontaneous, 12 achieved using clomiphene citrate and 17 induced by menotropins. The mean gestational age (weeks) at delivery was 36.5 ± 1.0 SD, for spontaneous and clomiphene citrate pregnancies it was 35.9 ± 1.9 SD which differed significantly from that in pregnancies induced by menotropins which was 32.9 ± 3.7 SD. Similarly, triplets born following menotropin treatment had a significantly lower gestational weight (g) of 1656 ± 516 SD vs. 2015 ± 198 SD and2176 ± 315 SD for spontaneous and clomiphene citrate gestations, respectively.It is concluded that triplets following menotropins are at an increased risk for premature delivery and low birth weight.

A generalized phenomenological model is presented for stereospecific recognition between biological receptors and their ligands. We ask what is the distribution of binding constants psi(K) between an arbitrary ligand and members of a large receptor repertoire, such as immunoglobulins or olfactory receptors. For binding surfaces with B potential subsite and S different types of subsite configurations, the number of successful elementary interactions obeys a binomial distribution. The discrete probability function psi(K) is then derived with assumptions on alpha, the free energy contribution per elementary interaction. The functional form of psi(K) may be universal, although the parameter values could vary for different ligand types. An estimate of the parameter values of psi(K) for iodovanillin, an analog of odorants and immunological haptens, is obtained by equilibrium dialysis experiments with nonimmune antibodies. Based on a simple relationship, predicted by the model, between the size of a receptor repertoire and its average maximal affinity toward an arbitrary ligand, the size of the olfactory receptor repertoire (Nolf) is calculated as 300-1000, in very good agreement with recent molecular biological studies. A very similar estimate, Nolf = 500, is independently derived by relating a theoretical distribution of maxima for psi(K) with published human olfactory threshold variations. The present model also has implications to the question of olfactory coding and to the analysis of specific anosmias, genetic deficits in perceiving particular odorants. More generally, the proposed model provides a better understanding of ligand specificity in biological receptors and could help in understanding their evolution.

Fetal activity in multiple pregnancies, as expressed by maternal daily fetal movement recordings, was compared with that in singleton pregnancies. It was found that the mean fetal activity in 33 cases of twins, six cases of triplets, one case of quadruplets, and one case of quintuplets was generally higher than that obtained during singleton pregnancies. In most cases, fetal movements of triplets, quadruplets, and quintuplets were even higher than the movement of twins.

Leukocyte alkaline phosphatase (LAP) activity was studied in 50 women at delivery and in the newborn after delivery. The foüowing findings were observed: (1) the LAP activity of newborns is lower than that of the mothers; (2) significant decrease in the LAP activity has been observed in newborns on the 4th day after delivery; (3) there are no significant differences between newborns from normal and prolonged labor; (4) immediately after delivery the LAP scores of male newborns are lower than those of females, but 4 days later these scores were reversed, and (5) 4 days after delivery, the LAP scores do correlate to the weight of the newborn.

Traumatic intrauterine adhesions are known to be reversible. In some cases, following lysis of adhesions we find residual adhesions on hysterography. We have studied 11 cases in whom new adhesion formation, of different type and location have recurred following curettage for lysis of adhesions or in subsequent pregnancy. In each case there were between two and five different forms of intrauterine adhesions during the course of study. In all 11 cases hypomenorrhea was a prominent symptom. On premenstrual curettage a scanty amount of endometrium was removed. Their obstetric history was characterized by sterility (four cases) and repeated early abortions, spontaneous or missed. Treatment consisted of repeated curettage and placement of an IUD. Four patients who subsequently become pregnant carried pregnancy to term or near term. Intrauterine adhesions may be considered as a localized manifestation of more generalized process of endometrial fibrosis. This may explain this syndrome of recurrent intrauterine adhesions and the paradoxical phenomenon of limited adhesions being associated with amenorrhea and hypomenorrhea.

Hypomenorrhea may be divided into functional (hormonal insufficiency or overstimulation) and organic types. This study concerns 23 consecutive cases of organic hypomenorrhea. Their chief complaints were sterility, habitual abortion, and hypomenorrhea. The diagnosis of the hypomenorrhea is based on the history, study of ovarian function, hysterography, laparoscopy, and diagnostic curettage. Three forms of organic hypomenorrhea are described: (1) Endometrial tuberculosis was found in 8 cases in which the diagnosis was based on tubercular changes in the endometrium or tubes and characteristic hysterographic changes including lymphatic intravasation. In all these cases the hypomenorrhea was primary. (2) Intrauterine adhesions were found in 6 cases. In all of these the hypomenorrhea was secondary to curettage in the puerperium or after abortion. Following the lysis of intrauterine adhesions, the menstrual pattern returned to normal. (3) Endometrial insufficiency (sclerosis) was found in 10 cases in which the secondary hypomenorrhea, which followed curettage in the puerperium or following abortion, was characterized by absence of intrauterine adhesions, normal ovarian function, absence of response to hormone therapy, scanty endometrial tissue on curettage, and a clinical picture of sterility or recurrent abortions.

The movements of the fetus in ulero are an expression of fetal well-being and depend mainly on the vascular state of the placenta. In cases of fetal risk due to placemal insufficiency and fetal disease, there is a decrease in the fetal movements. It was observed that before fetal death in utero due to chronic causes, such as toxemia of pregnancy, there is a definite decrease in fetal movements or cessation of movements although heartbeats are still audible. This is an alarm signal indicating severe intrauterine fetal asphyxia, requiring immediate delivery of the fetus

Leukocyte alkaline phosphatase (LAP) activity was determined in 222 women during normal pregnancy, labor, and after delivery. LAP scores rise during pregnancy and reach peak values at 24 to 26weeks’ gestation. Afterward, the scores remain constant and drop a few days before delivery. Administration of estrone in the last trimester of pregnancy causes an increase in LAP activity. No significant changes were noted after progesterone administration, while hydrocortisone decreased LAP activity. The resultant LAP store during pregnancy is an expression of placental function and may serve as an indicator of placental dysfunction.

Subcutaneous injection of the 5-hydroxytryptamine (5-HT) antagonist cyproheptadine hydrochloride (Periactin) produced a significant decrease in uptake of [14C]5-HT (serotonin) in the myometrium and to a lesser degree in the ovaries, foetuses and heart of pregnant rats. This effect of cyproheptadine was considerably increased in rats pretreated with the monoamine oxidase inhibitor pargyline hydrochloride. These results suggest that the anti-abortive effect of cyproheptadine is based on specific inhibition of the contractile effect of 5-HT on the myometrium. The hypothesis is advanced that cyproheptadine competes with serotonin for its receptors and thus blocks the effect of serotonin.

THE MOST common causes of liver damage during pregnancy are toxemia of pregnancy and coincidental viral or toxic hepatitis. Fatty metamorphosis of the liver (obstetric acute yellow atrophy) is a rare condition of unknown etiology which occurs in the last trimester of pregnancy and is almost always fatal.In 1883 Ahlfeld described a benign type of jaundice occurring during the last trimester of pregnancy and noted a tendency to recurrence during subsequent pregnancies.1 Additional early reports established that this disease is characterized by clinical and laboratory signs of biliary obstruction.2-4 During the past two decades more than a hundred patients have been described 5-33 and liver biopsies have been studied.* This paper reports the findings in five patients with recurrent cholestatic jaundice of pregnancy observed in Israel during the last five years, as well as the histological findings in the liver in one of the patients studied

Intra-uterine growth retardation may be classified by ultrasonography into symmetrical and asymmetrical. In the symmetrical type the biparietal diameter increases in parallel with, but below, the normal growth curve and the head to abdominal circumference ratio is normal. In the asymmetrical group the biparietal diameter is either normal or flattened, and deviates from the normal curve, whilst the head to abdomen circumference ratio is above normal in both situations. We have reviewed 34 cases of intra-uterine growth retarded fetuses. Ten of these were symmetrical of which five had malformations. Twenty-four were asymmetrical and in eighteen of them the mother had hypertensive disease. The course and outcome of pregnancy and labour were different in these two groups. This classification can be useful in planning the clinical management of pregnancies with fetal growth retardation.

Thromboplastic activity of amniotic fluid (TAAF) was determined in 97 normal and pathologic pregnancies using a modification of Quick's one-stage method for prothrombin time. It was shown that amniotic fluid (AF) has thromboplastic activity. This activity was found to increase with the progression of pregnancy, showing a very high correlation coefficient (r-0.86). In cases of pathologic pregnancies such as those associated with diabetes, toxemia, IUGR, and Rh incompatibility, the values of TAAF do not differ from normal pregnancies. However, in 7 of 10 cases of postmature pregnancies the TAAF was below 45 seconds while no pretcrm or term pregnancy showed TAAF of less than 45 seconds.

The effect of Doppler ultrasound (external cardiotacography) on fetal movements was evaluated in 90 women. Fetal movements were recorded by the patients for 20 minutes, after which the ultrasound equipment was connected unbeknown to the woman. Fetal heart rate and fetal movements were then recorded for an additional 20 minutes. The number of fetal movements registered was compared to the daily fetal movement recording. The results show that Doppler ultrasound used for continuous fetal heart rate monitoring does not influence fetal movements in normal, or mild or severe high risk pregnancies

Two cases of severe Rh-immunization are presented. The obstetric history, maternal serum anti-D titre, amniotic fluid spectrophotometric evaluation, amniography and ultrasound placentography suggest the diagnosis of hydrops fetalis. The reduction of fetal movements until cessation in the presence of an audible fetal heart point to a severely distressed fetus and impending death, thus providing additional data confirming the diagnosis of hydrops fetalis. The importance of diagnosed hydrops fetalis lies in the fact that most authors agree that in these cases treatment of the fetus should not be attempted.

It was previously demonstrated that in high-risk pregnancies, pronounced reduction of fetal movements until cessation, with audible fetal heart sounds, indicates severe fetal distress and impending death. Immediate delivery is indicated provided the fetus is viable. Three instances of cessation of fetal movements associated with polyhydramnios are reported; the fetuses proved to have malformations lethal for the newborn infant. These cases of polyhydramnios with diminished fetal movements stress the importance of investigating fetal morphology in this condition. Antenatal diagnosis of congenital anomalies may influence decisions about intervening in cases of decreased fetal movements.

Asymptomatic urinary tract infection occurs in approximately 5 per cent of pregnant women. If bacteriuria is detected in the first trimester and is not eradicated, about 25 per cent of these women will develop acute pyelonephritis during the third trimester or the puerperium. Several reports indicate that single-dose antibacterial therapy, applied at the asymptomatic stage, may be effective in such cases.