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Toxoplasmosis is caused by a parasite known as Toxoplasma gondii which, when passed from the mother to her fetus, causes severe complications. Affected fetuses can have calcium deposits in the brain causing blindness, convulsions and mental retardation. Prenatal testing techniques can be used to confirm a diagnosis of toxoplasmosis in the fetus. Fetal outcome was determined after diagnosis and treatment of fetal toxoplasmosis. Out of 1,270 cases of maternal toxoplasmosis infection, 89 infections appeared in the fetus. Consequences experienced by the fetus depend on the period of fetal growth during which the infection was acquired. Patients were grouped on the basis of the week of pregnancy that the mother acquired the infection. Pregnancies were terminated in 34 (2.7 percent) of the infected fetuses because of detected severe fetal brain abnormalities. Most of these fetuses contracted toxoplasmosis early in the pregnancy. All 53 patients received treatment with spiramycin; additional treatment with pyrimethamine and sulfonamides was given to 43 patients. Of the 54 infants born, no indication of brain or eye abnormalities were found in 44 infants (81 percent), although 41 infants had evidence of infection and 12 had a benign form of toxoplasma infection. Three of the infants had slight calcifications, while a severe condition was found in one infant not receiving the additional treatment. It is recommended that drug therapy with spiramycin for the mother start as early as possible to decrease the chances of a toxoplasmosis infection reaching the fetus. It was found that the longer the fetus was exposed to the infection, the more complications developed. Additional drug therapy appears to reduce the incidence of severe fetal complications.

The predicted sequence of human gastric cathepsin E (CTSE) was determined by analysis of cDNA clones isolated from a library constructed with poly(A+) RNA from a gastric adenocarcinoma cell line. The CTSE cDNA clones were identified using a set of complementary 18-base oligonucleotide probes specific for a 6-residue sequence surrounding the first active site of all previously characterized human aspartic proteinases. Sequence analysis of CTSE cDNA clones revealed a 1188-base pair open reading frame that exhibited 59% sequence identity with human pepsinogen A. The predicted CTSE amino acid sequence includes a 379-residue proenzyme (Mr= 40,883) and a 17-residue signal peptide. The predicted CTSE amino acid composition was consistent with that of purified material from gastric mucosa and gastric adenocarcinoma cell lines. Additional evidence for the identification of the CTSE cDNA clones was obtained by analysis of poly(A+) RNA isolated from CTSE-producing and -nonproducing gastric adenocarcinoma cell subclones. Three RNA transcripts (3.6, 2.6, and 2.1 kilobases) were identified in poly(A+) RNA isolated from a gastric adenocarcinoma cell line that produced CTSE that were absent from nonproducing subclones. CTSE contains 7 cysteine residues, of which 6 were localized by comparative maximal alignment analysis with pepsinogen A to conserved residues that form intrachain disulfide bonds. The seventh cysteine residue of CTSE is located within the activation peptide region of the proenzyme. We suspect that this residue forms an interchain disulfide bond and thereby determines the dimerization of CTSE proenzyme molecules that is observed under native conditions. The CTSE gene was localized to human chromosome 1 by concurrent cytogenetic and cDNA probe analyses of a panel of human × mouse somatic cell hybrids.