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A M Costello

Publications and source records attributed to A M Costello.

42 records · Page 3Linked to original sources
PubMed1983

Non-invasive investigation of cerebral metabolism in newborn infants by phosphorus nuclear magnetic resonance spectroscopy.

Intracellular metabolism in the brains of seven infants, born at 33-40 weeks' gestation and aged 44 h to 17 days, was studied on fourteen occasions by phosphorus nuclear magnetic resonance spectroscopy (31P NMRS). The characteristic spectral peaks of ATP, phosphocreatine (PCr), phosphodiesters, and inorganic orthophosphate (Pi) were always detected, together with a large peak attributed mainly to ribose-5-phosphate. The ratio of PCr to Pi NMRS signals (which are related to concentration) in one infant thought to have a normal brain was 1.7. In three infants who had severe birth asphyxia the PCr/Pi ratio ranged from 0.2 to 1.0 but increased as their clinical condition improved: infusions of mannitol solution caused a rapid increase in the ratio on four occasions in two of these infants. The PCr/Pi ratio was 1.4 in an infant with congenital cerebral atrophy and 0.7 in an infant with meningitis. Grossly abnormal 31P spectra antedated the detection by ultrasound of large porencephalic cysts in two infants. No systematic changes in intracellular pH (calculated from the chemical shift of the Pi resonance) were observed: the mean value for all observations was 7.2 +/- SD 0.1 (n = 14).

Adenosine Triphosphate↗
PubMedDate not supplied

Does antibody to mycobacterial antigens, including lipoarabinomannan, limit dissemination in childhood tuberculosis?

Serum immunoglobulin (Ig) G responses to a variety of mycobacterial antigens were measured in children from the UK, in children with tuberculosis from Hyderabad, India and Dhaka, Bangladesh, classified according to whether the disease was disseminated or localized, and in non-tuberculous controls. Anti-lipoarabinomannan (LAM) IgG responses in UK children showed a marked trough between 6 months and 3 years coincident with the reported peak incidence of disseminated tuberculosis. Geometric mean IgG responses to sonicates of slow-growing mycobacteria (rich in LAM) in 36 children with disseminated tuberculosis were markedly lower than in 99 children with localized tuberculous lesions (for Mycobacterium scrofulaceum P < 0.01, for M. tuberculosis P < 0.01, and for M. vaccae P < 0.01). Responses to purified LAM were also lower in the disseminated tuberculosis group (P < 0.05) but there was no difference between the groups in their response to mycobacterial 65 kDa protein. Multiple regression analysis showed that the reduced response to sonicated mycobacterial antigens and to LAM in children with disseminated disease was independent of age, nutritional status, skin test reactivity, duration of previous symptoms, and city of origin. There was no evidence for sequestration of antibody to immune complexes. These findings are compatible with the hypothesis that children with low levels of antibody to sonicated mycobacterial antigen and to LAM, or those who cannot mount an antibody response, are predisposed to dissemination. A role for antibody in preventing disseminated forms of tuberculosis in childhood has implications for the development of improved vaccines and for the optimum timing of vaccination with bacille Calmette-Guérin.

Adolescent↗
PubMedDate not supplied

Raised levels of agalactosyl IgG in childhood tuberculosis.

Raised levels of agalactosyl immunoglobulin G (IgG) have been found in adults with tuberculosis, Crohn's disease and rheumatoid arthritis, and recent evidence, both circumstantial and experimental, suggests that it has distinct functional properties that play a role in pathogenesis. Since tuberculosis in infants is strikingly different from the disease seen in adults, but switches to the adult form at adrenarche or puberty, we documented the association of agalactosyl IgG with tuberculosis in childhood between the ages of 0 and 16 years. Sera were collected from 99 children diagnosed as cases of tuberculosis in Istanbul, Turkey, and compared with levels in non-tuberculous controls. The percentage of agalactosyl IgG was significantly raised in children with tuberculosis overall (P < 0.001, Mann-Whitney U test) and in all age groups except for children over 12 years old, whose numbers were too small to be meaningful. Therefore the differences between adult and childhood tuberculosis are not due to a difference in the tendency for agalactosyl IgG to be produced at different ages. The percentage of agalactosyl IgG may be useful for monitoring the progress of individual complicated cases.

Adolescent↗