RESUMO
An infant had clinical signs suggestive of Hirschsprung disease as the initial manifestation of leukocyte adhesion deficiency. Chromosome studies showed a deletion of the distal third of the long arm of one chromosome 21, and flow cytometric studies confirmed the defective expression of CD18.
Assuntos
Doença de Hirschsprung/diagnóstico , Síndrome da Aderência Leucocítica Deficitária/diagnóstico , Antígenos CD11/sangue , Antígenos CD18/sangue , Deleção Cromossômica , Cromossomos Humanos Par 21 , Diagnóstico Diferencial , Evolução Fatal , Doença de Hirschsprung/genética , Humanos , Lactente , Síndrome da Aderência Leucocítica Deficitária/genética , MasculinoRESUMO
Evidence obtained on the relation between the pH of the medium and the growth of intact stem sections is compatible with the acid-growth theory only if the proton conductance of the cuticle is so low that the cuticle is an effective barrier to the entry or exit of protons from the tissue. By measuring the rate at which protons cross frozen-thawed epidermal strips of sunflower (Helianthus annuus L.) and soybean hypocotyls (Glycine max Morr.) and enzymically isolated cuticles of Berberis aquifolium Persh. and tomato (Lycopersicum esculentum Mill.) fruit, we have now demonstrated the low proton conductance of the cuticular layer. Unless the conductance is enhanced by abrasion of the cuticle or by removal of the cuticular waxes, proton movement into and out of a tissue across the cuticle will be significant only over long time periods.
