J A Bellanti

Congenital anaemia after transplacental B19 parvovirus infection.

We report three children with congenital anaemia after intrauterine infection with B19 parvovirus. All the fetuses developed hydrops fetalis that was treated by blood transfusion. After delivery the infants had hypogammaglobulinaemia. In all three, sera lacked B19 but viral DNA was found in bone marrow. All were treated with immunoglobulin. One child died and B19 was found in various tissues. In the other two cases, virus could no longer be detected after therapy but the patients remain persistently anaemic. Persistent B19 infection should be suspected in infants with congenital red-cell aplasia.

GLOMERULAR MICROTUBULES OF SYSTEMIC LUPUS ERYTHEMATOSUS

Abstract The association of systemic lupus erythematosus (S.L.E.) with myxovirus infection has recently been suggested on the basis of abnormal microtubular structures in glomeruli and elevated serum-antibody levels to certain viruses. Studies presented here suggest that the microtubular structures are not specifically related to myxoviruses, but occur in a variety of human diseases and experimental viral infections. Immunofluorescence and

LIVE ATTENUATED BACTERIAL VACCINES: NEW APPROACHES FOR SAFETY AND EFFICACY

Problems arising from reversion to virulence in genetically attenuated bacterial vaccines can be overcome by the combination, in one strain, of multiple temperature-sensitive mutations of identical phenotype. Immunogenicity of attenuated strains may be enhanced by incorporation of mutations which permit limited replication in the vaccinee (thereby increasing antigen mass while minimising the possibility of vaccine reactions) and the expression of genes coding for antigens which are synthesised only during infection of the host.

Immunological reactivity. Expression of efficiency in elimination of foreignness.

Abstract This hypothesis is a presentation of immunological phenomena as an array of potential responses of the host which are concerned with the elimination of any foreign substances. The immunological mechanisms which are stimulated are related to the degree of persistence of foreignness. Immunological imbalance and immunologically mediated diseases result when the type or intensity of the response is inappropriate to the stimulus.

Congenital anemia after transplacental B19 parvovirus infection

middle (MCA) and anterior (ACA) cerebral arteries during the first 10 days of life. One hundred thirty-seven of these infants were non-acidotic at delivery and during the early neonatal period, and had normal cerebral ultrasound scans throughout the study period. These infants formed the reference group. In three gestational subgroups considered (~32 weeks, 33-34 weeks, ~35 weeks) from the reference group, the median RI for both the ACA and MCA was noted to fall significantly during the first 12 h of life (P < 0.01 for all groups). For infants delivering at ~33 weeks gestation, both MCA and ACA RI values reached a steady state with no significant change in the median value for the remainder of the study period. For infants delivering at sz 32 weeks, there was a further significant fall in both the MCA and ACA RI between 12 and 24 h of life (P C 0.05). after which a steady state value was reached. During the first 12 h of life the RI for both vessels was significantly higher in infants delivering at 5 32 weeks compared to the more mature infants (P < 0.01) but for the remainder of the study period, there were no significant differences in RI values between the gestational subgroups. Reference data for MCA and ACA in the uncomplicated pre-term infant during the neonatal period are reported. This study demonstrates that significant changes occur in measures of cerebral vascular resistance, during the first few hours of life in the pre-term infant, possibly as the result of changes in blood gas tensions with the onset of respiration, or as a consequence of alterations in blood flow with the change from a fetal to an adult circulation, but in infants with normal cranial ultrasound scans, after the first 12-24 h, very little change in cerebral vascular RI occurs. Gestational age at delivery or influences the degree and speed with which these changes occur, but after the first 24 h of life is not a significant influencing factor on vascular resistance. Comparison of resistance changes occurring in the cerebral circulation during the neonatal period of pre-term infants who develop cerebral pathology with the reference data reported for similar infants without pathology may improve our understanding of the pathophysiological events associated with the development of such pathology.