Pseudomonoamniotic twins with cord entanglement following genetic funipuncture.

Amniocentesis was performed twice on a twin gestation, and twice there was cell growth failure in one of the twins. Therefore, funipuncture was attempted at 24 weeks. The anatomical relationship and position of the fetuses, placental cord insertion, and membranous septum dictated needle entry into the cord of the lower left fetus through the sac of the upper right fetus and the septum. The procedure was uneventful and the pregnancy was carried to 39 weeks. However, the septum between the twins had been disrupted, creating a pseudomonoamniotic pregnancy. This was noticed only after delivery of the first fetus, when it was found that the two umbilical cords were entangled. We believe that, whenever possible, puncture of the membrane between twins should be avoided. Should puncture be necessary, the possibility of pseudomonoamniotic twins must be considered.

The influence of different copper wires on human sperm penetration into bovine cervical mucus, in vitro.

The influence of four different copper-containing intrauterine devices (IUD) (Nova-T, Multiload, Fincoid 250 and copper-T 250) on the penetration of human sperm into bovine cervical mucus were assessed. Pooled samples of predetermined sperm concentration were suspended in Earl's medium in which a copper IUD was previously incubated for periods between one hour to fourteen days. The mean copper concentration was determined for each of the medium containing IUD and was found to be between 284 +/- 93 micrograms/100 ml to 392 +/- 138 micrograms/100ml. While there was no adverse effect on sperm motility by the copper-containing medium, there was a significant reduction in the number of sperm penetrated into the bovine cervical mucus as compared to the penetration of sperm suspended in pure Earl's medium. It therefore seems that the influence of copper on sperm penetration might be by an effect on the environment or spermatozoal migration rather than by direct effect of copper on sperm motility.

Hypergravity effects on litter size, nursing activity, prolactin, TSH, T3, and T4 in the rat.

Hypergravity (HG) adapted rats were tested for mating ability, gestational time, fetal and newborn mortality, and nursing performances. Plasma and pituitary PRL and TSH and plasma T3 T4 were determined during 48 h peripartum. No difference was noticed in mating ability and gestation time. The number of fetuses was reduced in the HG rats (1 G- 12.9 +/- 0.5, 2.16 G-10.5 +/- 0.4, 3.14 G-9.4 +/- 0.5). None of the 3.14 G rats nursed their young, all of which were cannibalized. Of the 2.16 G rats, 50% nursed their pups, of which only half survived to weaning. The initial pituitary PRL of HG rats was lower than 1 G, but it increased postpartum, while the plasma PRL, which was very low, continued to decrease. Only postpartum was there a difference in plasma PRL between rats that previously nursed and those which did not nurse at 2.16 G. HG rats had lower T3 levels, indicating a hypermetabolic state during the peripartum, which worsened their normal relative hypothyroid state of pregnancy. Our conclusions are that exposure of pregnant rats to HG above 3 G has a lethal effect on the fetuses and newborns. Maternal PRL and T3 changes are possible reasons for this.

Hypergravity induced prolactin surge in female rats.

Acute initial exposure to hypergravity (HG) was previously found to induce prolonged diestrous in rats, which was followed by return to normal estrous cycling upon more prolonged exposure to continuous HG. Bromergocryptine was found to prevent this prolonged diestrous. In this study we found that in female rats 20 h of 3.14 G exposure (D-1 1200 h until D-2 0800 h) can induce prolactin surge at D-2 1600 h. Shorter exposure time (8 h), or exposure during a different part of the estrous cycle (19 h: from D-1 0700 h until D-2 0200 h) could not elicit this prolactin surge. Similar exposure of male rats to HG did not alter significantly their prolactin levels. It is possible that the hypothalamus of male and female rats responds differently to stimulation by HG.

Intrauterine fetal response to hypergravity by reduction of plasma prolactin levels in the rat.

Rats were conceived after adaptation to 3.14 g. Maternal and fetal plasma prolactin levels were reduced on day 22 of gestation in the rats exposed to hypergravity. The fact that fetuses in utero respond in the same way as their mothers indicates that they too are sensitive to hypergravity and that the bouyant condition of the fetus does not interfere with such external stimulus.

Hypergravity: its effect on the estrous cycle and hormonal levels in female rats.

Hypergravity at 1.02-2.28 g was simulated by centrifugation and the estrous cycles of rats were followed by testing vaginal smears. Associated hormonal changes were measured from blood samples by radioimmunoassay. It was found that moderate hypergravity affects the estrous cycle by prolonging the diestrous period, and this effect seems to bear a direct relationship to the strength and timing of the hypergravity. Intermittent centrifugation produces the same effect as continuous centrifugation. After the prolonged diestrous, the estrous cycle returns to normal. The observed effects were associated with hormonal changes. Progesterone was elevated during the prolonged diestrous although no consistent changes in estrogen levels could be found. The effect of simulated hypergravity resembles the pseudo-pregnancy response produced in rats by various stimuli, but a decidual reaction, i.e., the usual uteral growth as a response to pregnancy or injury during pseudo-pregnancy, could not be elicited during the prolonged diestrous induced by 2.08 g. The possible mechanism eliciting the prolongation of diestrous is discussed.

The effects of micro-gravity on hornet's nest building and activity.

Principal scientific objectives: 1.) Comb building by hornet workers in micro-G: randomness of orientation, structural integrity, delay or rapidity of construction, all as a function of developmental state of the hornet. 2.) Dark-light effects on building hornets--will light provide building cues? 3.) Effect of domicile geometry on building practices--will the hornets build in spherical, domed or cube-shaped containers? 4.) Semiconductive properties of hornet cuticle and comb--will these be different than in the controls? Will the yellow granules developed in space be physico-chemically different from control granules? 5.) Post flight experiments--Will the hornets returned from space--build and oviposit as usual? Will the laid eggs embryonate? Will the comb be orientated as usual? How about other parameters of orientation (geotaxis) and social behavior (thigmotaxis)? Will there be any changes in the dominant gut microflora of returned hornets?

Reliability of sonographic measurement of the fetal foot.

Reliability of sonographic measurement of the fetal foot was tested. Nineteen fetuses of 16 to 40 weeks gestational age were scanned by two physicians in two different planes of measurements. Repeatability of two measurements of each fetus by the same observer and agreement between the two planes was analyzed using the appropriate statistical method. Good agreement in repeated measurements for and between the two planes was found.

Mode of delivery following external cephalic version and induction of labor at term.

External cephalic version should be followed by fetal and maternal surveillance until delivery. To shorten this period of surveillance, a protocol of version at term, followed by immediate induction of labor, was adopted. The aim of the present study was to evaluate the effect of this protocol on the subsequent mode of delivery. Two hundred and ninety-one singleton breech pregnancies were included in this study. Of these, 74 cases underwent version, 75% of which were successful. Success of version compared to failed version was associated with statistically significant (p < 0.001) lower rate of cesarean sections (9% and 67%, respectively). The overall rate of abdominal deliveries in the version group (74 cases) was statistically significantly lower compared with two other groups: one composed of breech pregnancies that did not undergo versions, but would have been qualified for it, had they been referred on time (121 cases), and the other (96 cases) that did not have versions done because of contraindications to its performance (cesarean rates, 23%, 54%, and 79%, respectively; p < 0.001). It may be concluded that a policy of external cephalic version at term is effective in lowering the incidence of cesarean deliveries, and the added intervention of induction of labor does not negate this effect.

ATP content in human semen and sperm quality.

Five semen characteristics (count, motility, normal forms, bovine cervical mucus penetration, and ATP) were evaluated in patients attending the infertility clinic. Multiple regression analysis indicated that the only characteristic independently affecting ATP concentration was sperm count, whereas motility and percent normal forms had no additional contribution to ATP level. Penetration into bovine cervical mucus did not depend on ATP levels. Comparison of semen characteristics in the same group between patients who have impregnated their wives and those who have not indicated that with respect to count, motility, morphology, and ATP the only sperm characteristic independently predicting fertility was motility. ATP measurements have limited value in the evaluation of semen quality.

Effect of washing and suspension on penetration of human sperm into bovine cervical mucus.

The in vitro penetration ability of human sperm into bovine cervical mucus after washing and suspension of the sperm in Earl's medium was compared with that of untreated sperm. The extent of penetration was found to be significantly lower in sperm washed and suspended in Earl's medium than in the unwashed sperm (p less than 0.0001); it increased to some extent on resuspension of the washed sperm in the seminal plasma but still remained significantly lower than that of intact sperm (p less than 0.009). The introduction of caffeine into the Earl's medium resulted in an increased penetration of the washed sperm into bovine cervical mucus, but this was still significantly lower than the penetration of the unwashed sample (p less than 0.02). The data point to the effectiveness of the seminal plasma as a medium facilitating sperm penetration through bovine cervical mucus.

Fetal habituation to repeated sound stimulation.

Habituation is the progressive decrement of response with repeated stimulation. Neonatologists use this phenomenon to assess newborns for various pathological conditions of the CNS. The present study examined the time required for habituation of the startle response in 103 fetuses at various gestational ages (32 to 40 weeks). The external stimulus was produced by a door buzzer (80 to 90 db). Habituation time decreased as gestational age increased. About 85% of the fetuses showed habituation after less than 20 stimuli, and about 95% after less than 30 stimuli. In all cases habituation time never exceeded 50 stimuli.

Hornet building orientation in a vertically rotating centrifuge.

Hornets build combs that are clearly oriented toward the center of gravity and they compensate for any change made in the direction of their cells, provided the gravitational vector remains unchanged. Under natural conditions the first few cells are built by the queen in the spring, following the hibernation period, and building is then continued by the workers. Recently several reports have been published concerning the fact that groups of hornets (V. orientalis workers) may build in the absence of the queen and that such combs resemble those built by the queen. In previous investigations on building orientation, hornets placed in artificial breeding boxes (ABBs) on a horizontal centrifuge were subjected to constant centrifugal and gravitational forces, the resultant of which ranged between 1-1.5 g. Under these conditions young hornets (1-2 days of age) built combs in the direction of the resultant force, while the direction of building by adult hornets (3-7 days of age) was dependent on the presence or absence of a straight roof. Adults placed in the ABBs of rectangular shape built combs the orientation of which was determined by the Earth's gravity alone (perpendicular to the roof) whereas those in spherical ABBs with a convex roof built combs in the direction of the resultant gravitational and centrifugal forces, much the same as combs built by the young hornets. We were, however, also interested in studying the building orientation of hornets placed under conditions of changing resultant forces. The present paper describes comb building by hornets under the alternating gravitational forces of a vertical centrifuge.