[Sensitivity of various primate cells and animal viruses to the antiviral activity of human leukocyte interferon (author's transl)]

U cells (a permanent, human amnion cell line) were protected against infection with Semliki Forest Virus (SFV) by human interferon (HIF) from peripheral leukocytes. Despite the usual genus-specific action of interferons, mouse L929 cultures (a permanent mouse fibroblast cell line) were also protected by HIF. The antiviral action of HIF in six other primate cell cultures was also examined. It is of interest that two lymphoblastoid cell lines, RPMI1788 and Kaplan, were insensitive to HIF. The sensitivity of ten different viruses against HIF in primary African green monkey kidney cell cultures was compared. Among the viruses tested SFV was the most sensitive whereas two strains of vaccinia virus were barely inhibited. In contrast, type 1 herpes simplex virus was relatively sensitive to the action of HIF.

Induction of abortion with intra-amniotic or intra-muscular 15(S)-15-methyl-prostaglandin F2alpha

In order to evaluate the efficacy and acceptability of 15(S)-15-methyl-prostaglandin F2alpha (15-me-PGF2alpha) for pregnancy termination, we induced 30 abortions with single intra-amniotic injections of 2,5 mg of 15-me-PGF2alpha and 25 abortions with intra-muscular 15-me-PGF2alpha administered 200 mug initially and 300 mug every third hour until 30 hrs or abortion. Abortion occurred within 30 hrs in 97% of cases in the intra-amniotic group, with a mean abortion time of 17,6 hrs and in 80% in the intramuscular group, with a mean abortion time of 15.0 hrs. Neither parity nor gestational age was significantly related to the abortifacient efficacy of 15-me-PGF2alpha. No serious complications occurred. Vomiting (83-84%) and diarrhoea (23-92%) were the most common complaints. Uterine contractions were more painful if induction was effected with intra-amniotic rather than intramuscular injections. 15-me-PGF2alpha appears to be an effective and practicable abortifacient which can be used intra-amniotically or intramuscularly according to the ease of amniocentesis.

Experimental in utero infection of fetal pigs with a porcine parvovirus

In utero infection of fetuses of six specific-pathogen-free large white sows at 35, 48, 55, 72, 99, and 105 days was studied. The fetuses were infected by direct inoculation of porcine parvovirus into the amniotic sac. The inoculation consisted of 0.25 ml of tissue culture fluid containing 10(5.5) mean tissue culture infective doses per ml of porcine parvovirus strain G10/1. Fetuses of one uterus horn were infected, whereas fetuses in the opposite horn were given 0.25 ml of noninfected cell culture material. No clinical signs of infection were observed; however, all sows developed antibodies 7 to 9 days postinfection. A total of 24 virus-inoculated fetuses and 20 control fetuses were studied. Fetuses infected at 35, 48, and 55 days of gestation died between about 5 and 22 days after infection. Virus was isolated from their organs and fetal blood. Virus spread to control fetuses but did not cause death and mummification or stimulate antibody production. Fetuses from sows infected at 72, 99, and 105 days of gestation survived. They developed high antibody titer in utero. Control piglets remained antibody free.

Surgical procedure for intraamnionic inoculation of the bovine fetus

A surgical procedure that ensures intraamnionic inoculation of the bovine fetus is described. Right flank surgical operation was performed, using a "grid"-type entry though the abdominal muscles. A portion of the uterus containing 1 fetal leg was presented for inoculating the test material between the hooves. The procedure was rapid and simple to do and was safe for both the dam and the fetus.

Fetal blood drawing

A small sample of fetal blood suitable for studies of haemoglobin synthesis was obtained from a placental vessel under endoscopic visualisation in 23 of 26 patients in whom the procedure was attempted prior to second-trimester abortion. Fetal blood loss, calculated in 23 cases, was between 0-2 ml. and 2-5 ml., and fetal blood-volume depletion varied from 0-5% to 15%. No short-term ill-effects were demonstrated in mother or fetus in any of 16 patients in whom the injection of aborti-facient was postponed for between 16 and 24 hours after the procedure.

Chorioamnionitis and colonization of the newborn infant with genital mycoplasmas

To study the role of Mycoplasma hominis and T-mycoplasmas (Ureaplasma urealyticum) in chorioamnionitis, we obtained culture from 249 puerperal women and their babies. The placentas were examined histologically. Infants whose placentas showed inflammation (chorioamnionitis) had cultures positive for T-mycoplasmas more frequently (37.5 per cent) than those with normal placentas (19.0 per cent) (P = 0.021). Colonization with M. hominis was found in 16.0 per cent of the babies and was not significantly associated with chorioamnionitis. Material colonization with mycoplasmas was more frequent (73.4 per cent) and was not correlated with placental inflammation. We conclude that a substantial proportion of cases of chorioamnionitis may be caused by prenatal infection with T-mycoplasmas. The fact that these organisms are not highly virulent could explain the frequent finding of inflammed placentas from otherwise normal pregnacies. No adverse clinical effects of the placental lesions or of mycoplasmal colonization could be detected in this small study.

Response of the primate fetus to intra-amniotic saline injection

The amniotic fluid was replaced with 20 per cent sodium chloride solution during the second half of gestation in 12 pregnant rhesus monkeys. This produced a congealing of the fetal blood in the small umbilical vessels which overlie in the placental chorionic plate. Death of severe asphyxia followed within 20 to 50 minutes in the younger fetuses due to a prompt cessation of umbilical blood flow. During this time, the rise in serum sodium of the fetus was moderate and could not be implicated as the cause of fetal death. In older fetuses, the asphyxia produced by the saline injection was transient and less severe, occasionally permitting survival. The caliber of the affected fetal umbilical blood vessels and their blood flow rates are presented as the principal determinants of the rapidity of development and the severity of the asphyxia produced by saline instillation.

[Rat ovarian function after post or prenatal injection of clomiphen]

If newborn rats are subcutaneously injected with 0,075--0,100 mg of Clomiphene Citrate within the first 5 days, it results that 73.7% of the females remain anovulatory. The percentage rises to 100 if 0,125--0,400 mg are given in several injections. The identical treatment has no influence on the testicular function. Prenatal administration to pregnant rats (total amount 0,250--2,70 mg in repeated subcutaneous injections) interrupts the pregnancy in a high percentage, but has no effect on the later gonadal function of the foetuses. Equally ineffective is the prenatal intra-amniotic injection of clomiphene (0,125--0,250 mg into each amniotic cavity). In this respect the action of Clomiphene differs from the action of testosterone and also of estradiol, as these two hormones produce the identical effect after intra-amniotic as after postnatal administration i.e. they are effective if passage through the placenta is avoided. Clomiphene, postnatally effective, loses its effectiveness when intra-amniotically injected, although the placenta is eluded. An inactivating action of the amnion fluid could be the explanation of this phenomenon.

Uterine activity in induced labour

A study was made of the characteristics of oxytocin-induced labour. Twelve patients with, and eight without membrane rupture were closely matched for factors likely to influence the character and duration of labour. In both groups uterine activity increased until a stable state was achieved loowing which there was little alteration until delviery. The duration of labour was shorten in the group with ruptured membranes as compared with intact membranes although, paradoxically, the uterineactivity tended to be greater when the membranes were intact.

Rate of fall in plasma progesterone and time to abortion following intra-amniotic injection of prostaglandin F2alpha, with or without urea, in the second trimester of human pregnancy

Progesterone concentrations have been determined in a total of 175 peripheral plasma samples obtained serially from 20 women undergoing mid-trimester abortion. In ten patients abortion was induced in intra-amniotic administration of 50 mg. of prostaglandin F2alpha (PGF 2alpha) alone; in ten others it was induced with 50 mg. of intra-amniotic PGF2alpha with 80 g. of urea. Mean instillation-abortion intervals were 29-0 hours in the group receiving PGF2alpha alone and 12-1 hours in the groups receiving PGF2alpha and urea. In eight of the patients treated with PGF2alpha and urea, and in four of those treated with PGF2alpha alone, there were significant decreases in progesterone level (determined by calculation of correlation coefficients) during the instillation-abortion iterval. When plotted against instillation-abortion times, calculated rates of decease in peripheral plasma progesterone levels showed a statistically significant regression (p smaller than 0-05). This indicates that progesterone levels drop most rapidly in patients with shorter instillation-abortion times. There was no relationship between initial progesterone levels and instillation-abortion times.

Isolates of California encephalitis (La Crosse) virus from field-collected eggs and larvae of Aedes triseriatus: identification of the overwintering site of California encephalitis

California encephalitis is caused primarily by La Crosse virus, a mosquito-borne agent of which the vector is the mosquito Aedes triseriatus. Once La Crosse virus has been detected in a given geographical area, observations in the same area during subsequent seasons usually have revealed continuing presence of the virus. Field studies were conducted around the homes of children who had had California encephalitis in an effort to define the mechanism by which the virus survived the winter. Eggs and larvae of A. triseriatus collected from natural breeding sites during the springs and summers of 1972-1974 were processed for viral isolation. Collections made during 1972 and 1973 yielded no virus. Eggs, obtained on April 29, 1974 from a basal tree hole of an American elm located approximately 150 feet from the homes of two children who had had California encephalitis in 1970, contained virus, as did larvae aspirated on May 16, 1974, from the same tree hole. This study in Minnesota confirms previous data from Wisconsin and suggests that La Crosse virus may be passed transovarially in A. triseriatus and may overwinter in the diapause stage of eggs.

In utero immunization of calves against colisepticemia

A total of 21 bovine fetuses was inoculated in utero with Escherichia coli antigen to determine if nonserotype-specific resistance to colisepticemia could be induced. (Seven of these fetuses were inoculated through the intact flank of the dam.) After birth, the calves were deprived of colostrum and challenge exposed to a serologically distinct E coli which killed nonvaccinated controls. Of 21 calves vaccinated as fetuses, 10 survived challenge exposure, 8 died of colisepticemia, and 3 were stillborn. Premature birth precluded an adequate period of vaccination in 6 of the calves that died of colisepticemia. A relationship was not observed between E coli serum antibody and survival after challenge exposure. The results indicate that in utero vaccination with a single serotype of E coli can result in heterogenetic protection against neonatal colisepticemia. However, the occurrence of stillbirth and premature birth in calves vaccinated in utero indicates need for furthur research before field application of this technique.

Perinatal infection and vaginal flora

Vaginal cultures were obtained from 1, 083 mothers on admission to the labor floor. The additional bacteriologic information gained from this survey was not sufficient to warrant continued use of the admission vaginal culture as a screening procedure.

Prostaglandin F2alpha given by continuous transcervical extra-amniotic infusion combined with intravenous oxytocin infusion for therapeutic termination of mid-trimester pregnancies

Prostaglandin F2alpha administered by continuous transcervical extra-amniotic infusion, and supplemented with oxytocin, given intravenously, to induce therapeutic abortion during the second trimester in 50 cases. This method was successful in all cases and has the advantages of being technically simple and requiring only a small dose of prostaglandin. The main hazard is intrauterine infection, which can be prevented by preliminary bacteriological investigation of the cervix and appropriate prophylactic antibiotic therapy. Prostaglandins are not yet available in Australia for general medical use. Our experience with prostaglandin F2alpha administered in the manner described indicates that it has an important part to play in gynaecological therapy.

Electroencephalographic changes after intra-amniotic prostaglandin F2alpha and hypertonic saline

Six major convulsions have been seen among 555 patients who had therapeutic second trimester abortion by intra-amniotic prostaglandin F2alpha (PGF2alpha). Five of 21 patients receiving intra-amniotic hypertonic saline and 5 of 16 patients receiving PGF2alpha showed abnormalities in electroencephalograms after treatment. These changes were relatively minor in all saline patients and in three receiving PGF2alpha, but two patients receiving PGF2alpha showed epileptiform spike activity after infusion. There was no correlation between the electroencephalographic (EEG) changes and peripheral venous levels of PGF2alpha or its metabolite, 13, 14 dihydro-15 keto PGF2alpha (15 keto-h2-f2alpha).

[The amniotic infection syndrome and premature rupture of the amnion. Manifest and threatening unspecific intra-uterine infections of the last third of pregnancy (author's transl)]

In the last third of pregnancy the unspecific bacterial diseases of placenta, umbilical cord and membranes differ from those in earlier months [154; 155; 85]. There is a parallel change in the localization of fetal organs affected. Pathologic anatomical clarification of this led to the conceptual definition of the rare extra-amnial placental-fetal path of infection on the one hand and of primary intra-amnial infection with secondary chorion-amnionitis on the other hand and to identification of the amniotic infection syndrome as a typical entity at the end of pregnancy [19]. While the amnionic sac is closed, unspecific fetal inflammation is rare. Generally this happens only after rupture of the membranes. Since the amniotic infection syndrome often produces only minor clinical symptoms and since fetal infection probably starts early, one searched for means of assessing the risk of infection independently from symptoms. In comparative series of investigations of pregnancies with and without premature rupture of the membranes, cases of neonatal death from infection were preceded by signs of inflammation in placenta, umbilical cord and membranes. Together with the fetal and maternal infections they depended on the length of time between rupture and the onset of labor. pns. The data now available give a clear picture of the development of the inflammatory processes in mature and premature children and suffice for the assessment of fetal and maternal risks.

Association of tissue factor activity with the surface of cultured cells

Tissue factor occurs in a dormant state on the surface of cultured normal human fibroblasts and WISH 1 amnion cells. The activity of undisturbed monolayers or cells lifted with brief trypsin treatment (0.125 per cent trypsin for 1 min) increases up to 60-fold upon prolonged digestion with dilute trypsin (0.0025 per cent trypsin for 30 min); activity appears subsequent to cell detachment. Up to 70 per cent of the total cellular tissue factor becomes active under these conditions and is released from the cells. The ruthenium red staining coat of the cells is lost during detachment, but cell viability (more than 90 per cent exclude trypan blue) and cell morphology do not change during the subsequent development of tissue factor activity. Furthermore, less than 10 percent of four intracellular enzymes and less than 20 per cent of two plasma membrane enzymes are released during this period of time. We therefore conclude that cells in culture do have tissue factor activity, that it exists in a latent form, and that total cell disruption is not necessary for this activity to initiate blood coagulation.