Search PubMed⌕ Search

Biomedical subjects

J Joncas

Publications and source records attributed to J Joncas.

At least 37 records · Page 2Linked to original sources
PubMed1974

Epstein-Barr virus infection in the neonatal period and in childhood.

In an attempt to detect and characterize congenital, neonatal and early childhood EBV infections, a prospective sero-epidemiological study was undertaken in 112 newborn infants and their mothers, 25 additional newborns undergoing exchange transfusion, 114 randomly selected hospitalized infants aged 0 to 3 years, and 109 siblings and parents of these infants. Leukocyte culture was attempted in all the newborns and in 25 pre- and post-transfusion.The findings of EBV seroconversion in six patients without clearly apparent illness, infectious mononucleosis in only one case with significant EBV antibody rise, seroreversion in three cases in early childhood, higher newborn than maternal EBV antibody titres in three cases and the establishment of two permanent lymphoblastoid cell lines from newborns following exchange transfusion raise the possibility of abortive primary EBV infection in early life. Congenital or neonatal infections following exchange transfusions, however, could not be substantiated with certainty since the EBV antibodies did not persist at follow-up except possibly in two cases. Parenteral transmission of the EB virus by exchange transfusion at birth is probably prevented by the presence of EBV antibodies in either donor or recipient.

Antibodies, Viral↗
PubMed1970

Serological response of the EBV antibodies in pediatric cases of infectious mononucleosis and in their contacts.

The EBV antibodies were measured in 378 sera from a group of 129 pediatric and older cases of infectious mononucleosis and from 117 family and social contacts. Cases of infectious mononucleosis with only one exception were EBV seropositive in acute and/or convalescent sera. Fourteen cases, however, from whom no convalescent serum was available were EBV seronegative. A rise in EBV antibodies of two dilutions or more was demonstrated in 15 of the 129 cases. The prevalence of these antibodies in contacts reached 50 to 70% in each of four age groups. A significant antibody rise was encountered in only four cases, one of whom was found to have infectious mononucleosis simultaneously with the index case and one after an interdisease period of 10 months. The infectivity of the EB virus (and of infectious mononucleosis if causally related) and its horizontal transmission seem to be as low in nature as they appear to be experimentally in the laboratory.

Adolescent↗
PubMed1967

Studies on infectious mononucleosis: a progress report.

The authors recently reported the occurrence of an unstable cytopathic effect and a "first passage" interference phenomenon in tissue culture as well as the detection of antigens by immunofluorescence following inoculation of material from patients with infectious mononucleosis.These tissue cultures have since been discovered to be contaminated by a bacterial L-form. The part played by the contaminant in the results obtained has been determined: it can explain only one of the patterns shown by immunofluorescence.The same labile interference phenomenon has been observed by two independent investigators.

Humans↗
PubMed1967

Infectious mononucleosis.

A short review of past and recent works pertinent to the etiology and pathogenesis of infectious mononucleosis is presented. Epidemiological studies have led to the elaboration of hypotheses concerning the etiology, the length of the incubation period and the mode of transmission of the disease. An unusual type of infectious mononucleosis of rickettsial origin has been reported by Japanese workers. Studies of accidental and experimental transmission suggest that more than one agent may give rise to the same disease. Isolation attempts in tissue cultures have been unrewarding except for the uncovering of possible agents by interference and immunofluorescence.The atypical lymphocyte is the site of increased RNA and DNA synthesis. It does not seem to be involved in antibody synthesis. The heterophile agglutinins and other mononucleosis-associated antibodies apparently account for only part of the excess 19S antibody material found in mononucleosis sera. The origin and function of these antibodies and of the atypical lymphocyte are the subject of speculation.The final elucidation of the pathogenesis of the disease and the confirmation of the reviewed hypotheses are all dependent on the eventual discovery of the elusive etiological agent(s) of infectious mononucleosis.

Adult↗