Effect of cyclophosphamide pretreatment on autoimmune encephalomyelitis in rats.

We studied the effect of a low dose cyclophosphamide (CY) treatment on the clinical course of experimental autoimmune encephalomyelitis (EAE) in rats from three resistant or low-susceptible strains: Fischer, Brown-Norway, PVG, and the F1 hybrid between the two former strains. Treatment with 40 mg/kg two days before immunization resulted in a marked potentiation of EAE development in Fischer and PVG rats, but not in BN rats or F1(BN X F) hybrids. The effect of the CY treatment was a short period of severe lymphoid cell depletion with an increase in the quotient between T cells reacting with w3/25 monoclonal antiserum and such reacting with ox-8 antiserum, indicating a relative reduction in suppressor/cytotoxic cell counts.

Dissociation between histological and clinical signs of experimental auto-immune encephalomyelitis.

Lewis rats show a rough correlation between clinical score and histological score of auto-immune encephalomyelitis (EAE). When animals with strong and comparable clinical EAE but with different genetic backgrounds are studied four weeks after immunization, they reveal histological changes that vary markedly according to the genetic set-up. When studied at the height of the EAE attack, also rats with a very low histological score at day 28 have marked histological changes.

A register study of maternal epilepsy and delivery outcome with special reference to drug use.

A study has been made on epilepsy and delivery using the Swedish Medical Birth Register, 1973-1981. A total of 635 women with 712 infants were identified with the diagnosis of epilepsy in the register--they represented 1/3 to 1/4 of the expected number. An analysis of the delivery outcome did not indicate a registration bias favouring poor delivery outcome.

Intestinal bypass operation and pregnancy outcome.

With the aid of the national Medical Birth Registries and Discharge Registries in Denmark and Sweden it was possible to identify and study delivery outcome in 77 women who, prior to pregnancy, had undergone an intestinal bypass operation for obesity. Analysis of birth weight and pregnancy length distribution showed that infants borne by these women had an increased rate of low birth weight, short gestation, and also growth retardation. There were no distinct differences between those infants that were conceived less than 24 months or more than 24 months after operation.

An epidemiological study of work with video screens and pregnancy outcome: II. A case-control study.

A case-control study on work with video screen equipment during pregnancy has been made for three cohorts of women, identified with the aid of occupational codes in the census, linked to the Medical Birth Registry and a registry containing information on women hospitalized for spontaneous abortion. Five hundred and twenty-two cases were selected (women with spontaneous abortions or women who had infants that died, had severe malformations, or had a birth-weight below 1,500 g) and 1,032 controls (women who had infants without any of these characteristics) taken from the same age stratum as the cases. All pregnancies had occurred in 1980-81.

An epidemiological study of work with video screens and pregnancy outcome: I. A registry study.

Three cohorts of women were identified with the aid of occupational codes in the census, linked to the Medical Birth Registry and an Inpatient Registry, containing information on women hospitalized for spontaneous abortion. The three cohorts were selected from the same socioeconomic stratum but had different probabilities to be exposed for video screen work: high, medium, and low. The total pregnancy outcome of the three groups of women did not differ significantly, but there was a weak trend for more spontaneous abortions and perhaps also for congenital malformations in the group with the highest video screen work exposure; however, the differences could be random.

Congenital malformations in twins: a population study.

Malformations in twins were studied with the use of a Medical Birth Registry covering nearly all births in Sweden, 1973-1981. A total of 15,427 infants marked twins were identified and the malformation diagnoses were analyzed, comparing rates with the overall rates in the same data source. Problems in ascertainment and interpretation are discussed.

Lack of histological signs in rats dying during the acute phase of experimental auto-immune encephalomyelitis.

Rats dying acutely of experimental auto-immune encephalomyelitis show very meagre histological signs of the disease in routine histology sections. This cannot be explained by postmortal changes. It is suggested that the infiltrating lymphoid cells seen in the central nervous system for surviving rats are involved in the normally occurring self-limitation of the disease.

Effect of Bordetella pertussis vaccine on experimental autoimmune encephalomyelitis in rats.

Administration of Bordetella pertussis vaccine simultaneously with the immunization of rats with guinea pig encephalitogenic protein in Freund's complete adjuvant results in the development of hyperacute encephalomyelitis in the Lewis strain, a strain which reacts with ordinary experimental autoimmune encephalomyelitis (EAE) when immunization is performed without pertussis vaccine. A marked augmentation of the EAE response was seen with pertussis vaccine in the Fischer and PVG strains, both low responders without pertussis, and relapsing EAE developed in some animals. Hyperacute EAE did not develop, however.

A joint international study on the epidemiology of hypospadias.

A descriptive epidemiological study of hypospadias has been made utilizing data from seven malformation surveillance systems round the world: Denmark, Hungary, Italy, Mexico, South America, Spain, and Sweden. The joint material represents 8,122 boys with hypospadias, 7,419 of which were "isolated", that is, with no other known malformation except those obviously related to hypospadias (undescended testis, hydrocele, scrotum anomalies). The main study was based on the infants with isolated hypospadias, but an analysis of multimalformed infants with hypospadias was also made.

A study of pregnancy outcome in a small area around a chemical factory and a chemical dump.

Pregnancy outcome was studied in three parishes situated around a chemical factory from which air and water pollution was considered to have occurred. Data on health variables were mainly obtained from registries supplemented with hospital record information. No definite reproductive hazards could be demonstrated but an unusually high perinatal death rate among twins born in the area was noticed.

Effect of splenectomy on the development of experimental autoimmune encephalomyelitis in rats with different genetic background.

We studied the effect of total or partial splenectomy on experimental autoimmune encephalomyelitis (EAE) development in rats with different genetic background after immunization with guinea pig basic encephalitogenic protein in Freund's complete adjuvant. The operations did not affect some strains with a high susceptibility to EAE but may have reduced the EAE development in the Fischer strain, which shows only a weak susceptibility. In some hybrids and backcrosses, but not in others, splenectomy resulted in a clear-cut reduction of neurological signs of EAE.

A study of some immunological variables in twins, discordant for multiple sclerosis.

11 twin pairs, discordant for multiple sclerosis (MS), were studied: 5 were monozygotic, 6 dizygotic. The mixed leukocyte reaction (MLR) with cells from unrelated patients with MS, the natural killer cell (NK) activity, OKT 4/OKT 8 ratio, and monocyte numbers were studied. The impaired MLR seen in some patients with MS was even more pronounced in the healthy twin, irrespective of the zygosity of the twins.

Time trends of spina bifida in Sweden 1947-81.

The spina bifida rate in Sweden from 1947 to 1981 has been studied using various sources of information, including two central computerised registers. During the period the rate approximately halved, but the decline was not smooth and occurred in three "waves." When the geographical location of high risk areas within each wave was studied, they were found to differ.

Infants with congenital limb reduction registered in the Swedish Register of Congenital Malformations.

Limb reduction defects reported to the Swedish Register of Congenital Malformations 1965-1979 have been analyzed from a monitoring point of view. The infants were first studied with respect to the site of reduction malformation and the simultaneous presence of more than one such reduction site. Reductions often occurring together were thought to have a common pathogenesis (etiology) and were therefore treated as one unity although some such groups (e.

Delivery outcome of women working in laboratories during pregnancy.

By record-linkage of the 1975 Swedish census and the Medical Birth Register of infants born in 1976, 1,161 infants were identified who were born to women coded as laboratory workers in the census. These infants were compared to all 98,354 infants born in Sweden in 1976. There was a higher than expected number of infants who died neonatally and/or had congenital malformations.

Lithium and pregnancy. A cohort study on manic-depressive women.

By record linkage of a discharge diagnosis registry and a medical birth registry we identified 350 women with manic-depressive disease who had born a child. The total delivery outcome was poorer than expected with a high perinatal death rate and a high malformation rate. Further studies revealed a high rate of perinatal deaths and/or congenital malformations among infants born of women who had used drugs in early pregnancy, and this phenomenon was concentrated to women who had used lithium and to heart defects.

Clusters of malformations in Sweden: a study with central registers.

Clustering of malformations and especially of spina bifida in Sweden was studied using the Register of Malformations and the Medical Birth Records Register. The incentive to this study was provided by the observation of a cluster of malformations, notably spina bifida, and perinatal deaths, locally thought to be related to the use of herbicides in forestry. This cluster was verified but it was shown that a high rate of spina bifida existed in the region before the introduction of herbicides in forestry.

Lack of correlation between contraceptive pills and Down's syndrome.

A case-control study has been made on the use of oral contraceptives before pregnancy and the birth of an infant with Down's syndrome. Controls were matched for age and parity and selected from the Medical Birth Register. Information on Pill usage was obtained from the Swedish standardized maternity health record which contains dates for when the women stopped using the Pill and for last menstrual period.

A women's birth cohort effect on malformation rates.

A relatively sudden increase in prevalence at birth of gastroschisis was seen in Sweden at the beginning of the 1970s. Case-control studies, looking for a teratogenic factor, have proved negative. This paper presents a hypothesis suggesting that the women's birth cohort has an effect: women born in 1953-5 have an increased probability of having this type of malformed infants.