No abstract

Although palatal shelf adhesion is a crucial event during palate development, little work has been carried out to determine which molecules are responsible for this process. Furthermore, whether altered palatal shelf adhesion causes the cleft palate presented by Tgf-b 3 null mutant mice has not yet been clarified. Here, we study the presence/distribution of some extracellular matrix and cell adhesion molecules at the time of the contact of palatal shelves in both wild-type and Tgf-b 3 null mutant palates of two strains of mice (C57/BL/6J (C57), and MF1) that develop cleft palates of different severity. We have performed immunohistochemistry with antibodies against collagens IV and IX, laminin, fibronectin, the a 5 -and b 1 -integrins, and ICAM-1; in situ hybridization with a Nectin-1 riboprobe; and palatal shelf cultures treated or untreated with TGF-b 3 or neutralizing antibodies against fibronectin or the a 5 -integrin. Our results show the location of these molecules in the wild-type mouse medial edge epithelium (MEE) of both strains at the time of the contact of palatal shelves; the heavier (C57) and milder (MF1) alteration of their presence in the Tgf-b 3 null mutants; the importance of TGF-b 3 to restore their normal pattern of expression; and the crucial role of fibronectin and the a 5 -integrin in palatal shelf adhesion. We thus provide insight into the molecular bases of this important process and the cleft palate presented by Tgf-b 3 null mutant mice.Key words cleft palate Á Tgf-b 3 Á mouse Á collagen Á laminin Á fibronectin Á a 5 b 1 -integrin Á ICAM-1 Á Nectin-1

Objective: To analyse the diagnostic role of serum IGF-I, IGF-binding protein-3 (IGFBP-3), IGF-I/IGFBP-3 molar ratio and urinary GH (uGH) excretion in adult GH deficiency (GHD). Design: Twenty-seven adults (age range: 18-71 years) with severe GHD, defined by a peak GH response to an insulin tolerance test below 3 mg/l in patients with at least one additional pituitary hypofunction. Reference values were established from a selected age-and body mass index-matched population (154 healthy adults grouped in four age groups). Methods: IGF-I and IGFBP-3 were measured by RIA (Nichols) and results expressed as standard deviation (S.D.) scores from our reference population and assay normative data (S.D. score Nichols). uGH was measured by IRMA. Results: Within the control group, IGF-I, IGFBP-3, IGF-I/IGFBP-3 ratio standardisation regarding our control population and IGF-I with respect to the assay normative data resulted in disappearance of agerelated differences. However, IGFBP-3 S.D. score Nichols resulted in mean values between þ1.4 and þ2.5 S.D. score. Greatest diagnostic efficiency was for IGF-I standardised with respect to our controls (97.2%), followed by S.D. score IGFBP-3 (92.9%). S.D. score IGF/IGFBP-3 ratio and uGH showed poor diagnostic efficiency. Any combination of at least two abnormal parameters raised specificity to 100%. IGF-I standardised with respect to assay reference (S.D. score Nichols) showed similar diagnostic value (95.0%) whereas IGFBP-3 showed low sensitivity (33.3%). Within the GHD patients, those with three or more additional deficiencies had lower S.D. score IGF-I than those with only two or one. Conclusion: We underline the importance of an appropriate reference population for correct interpretation of GH secretion markers. Considering our results, specificity obtained with two simultaneous abnormal parameters when referred to an adequate reference population may add valuable information to alternative GH stimulation tests to confirm adult GHD.