Decreased expression of tumor necrosis factor family receptors involved in humoral immune responses in preterm neonates.

Neonates have an increased rate of infection with encapsulated bacteria compared with older children and adults because of diminished antibody responses to T-independent (TI) antigens such as bacterial polysaccharides. Because the interactions of tumor necrosis factor (TNF) family ligands BAFF and APRIL with the TNF family receptors (TNFRs) TACI, BCMA, and BAFF-R are crucial to TI antibody responses, we measured the expression of these receptors on adult and cord blood-derived term and preterm neonatal B cells. Preterm neonatal B cells expressed less TACI, BCMA, and BAFF-R compared with adult B cells and had significantly less proliferation compared with adult B cells after stimulation with human recombinant BAFF and anti-IgM in an assay in which TACI-Fc fusion protein inhibits B-cell proliferation. In addition, neonatal dendritic cells had diminished expression of B7-1, B7-2, and CD40 compared with adult cells. Finally, neonatal B cells, particularly preterm B cells, exhibited markedly decreased production of IgG and IgA in response to CD40L and IL-10. Overall, this study shows that maturational delay in TNFR expression particularly by preterm neonatal B cells may interfere with effective antibody responses to TI antigens, cognate T- and B-cell interactions and normal isotype switching.

Repair of tympanic membrane perforation by topical application of 1% sodium hyaluronate.

OBJECTIVE: The administration of exogenous hyaluronic acid can increase the repair potential of damaged tissue. This study was conducted to verify whether or not the hyaluronic acid enhances the repair process in perforations of tympanic membrane. Hyaluronic acid is commercially available as its sodium salt. STUDY DESIGN: Thirty patients with dry central perforations of small or medium size (up to 3 mm) were treated locally with 1% sodium hyaluronate. The applications were repeated weekly for a maximum of five applications. RESULTS: It was found that treatment with sodium hyaluronate helps appreciably in the closure of tympanic membrane perforations and also that the scar formed in majority of them resembled the normal tympanic membrane. 86.67% (26/30) of the patients responded positively to the treatment. More importantly overall average percentage reduction in the size of perforations was 86.49%. CONCLUSIONS: It was concluded that topical application of 1% sodium hyaluronate can be an alternative to surgery in selected cases of tympanic membrane perforations.

Comparative evaluation of Teller and Cardiff acuity tests in normals and unilateral amblyopes in under-two-year-olds.

PURPOSE: To compare and evaluate Teller Acuity Cards (TAC) and Cardiff Acuity Cards (CAC) to assess vision in children below the age of two. METHODS: The study evaluated TAC and CAC to assess visual acuity in 90 normal children divided into three age groups, 0-6 months (group I), 6-12 months (group II) and 12-24 months (group III). 30 cases of unilateral amblyopiogenic conditions, 10 cases each of unilateral refractive error, unilateral esotropia, and unilateral cataract, were also examined. Trained optometrists carried out binocular testing followed by monocular testing, and recorded the test time in each case. RESULTS: The mean visual acuity (in Snellen units) and standard deviation (in octaves) in the three age groups of normal children, I, II, III respectively were 6/44 +/- 0.54, 6/21 +/- 0.37 and 6/21 +/- 0.41 (binocularly by TAC) and 6/46 +/- 0.80, 6/21 +/- 0.59 and 6/14.5 +/- 0.84 (binocularly by CAC). Although the time taken for testing with CAC was less, its coefficient of variance was greater for all age groups as compared to TAC. Diminution of visual acuity could be assessed correctly by both the tests in cases of strabismus and cataract, but not in some cases of refractive error. CONCLUSION: CAC is a useful and child-friendly test. It can be used clinically but may miss some cases of visually significant refractive errors. TAC is a more dependable test to assess amblyopiogenic conditions despite the use of gratings.