Neurofibromatosis type 1 (NF1) is characterized by cafe-au-lait spots, skinfold freckling, and cutaneous neurofibromas. No obvious relationships between small mutations (<20 bp) of the NF1 gene and a specific phenotype have previously been demonstrated, which suggests that interaction with either unlinked modifying genes and/or the normal NF1 allele may be involved in the development of the particular clinical features associated with NF1. We identified 21 unrelated probands with NF1 (14 familial and 7 sporadic cases) who were all found to have the same c.2970-2972 delAAT (p.990delM) mutation but no cutaneous neurofibromas or clinically obvious plexiform neurofibromas. Molecular analysis identified the same 3-bp inframe deletion (c.2970-2972 delAAT) in exon 17 of the NF1 gene in all affected subjects. The Delta AAT mutation is predicted to result in the loss of one of two adjacent methionines (codon 991 or 992) ( Delta Met991), in conjunction with silent ACA-->ACG change of codon 990. These two methionine residues are located in a highly conserved region of neurofibromin and are expected, therefore, to have a functional role in the protein. Our data represent results from the first study to correlate a specific small mutation of the NF1 gene to the expression of a particular clinical phenotype. The biological mechanism that relates this specific mutation to the suppression of cutaneous neurofibroma development is unknown.

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Aim: To study the effect of Zn supplements in cystic fibrosis (CF) on disease evolution. Methods: A retrospective study of all CF patients treated with Zn supplements (January 2002 to December 2004). Data from patient files for the year before and the first year of supplementation were compared. The controls were CF patients with normal serum Zn and without Zn supplementation. Results: 21 patients (7 females), median age 8.9 (interquartile range 13.1) years, received 5 mg/kg Zn sulfate/day (maximum 150 mg). The number of infections decreased from 3 (1.25) to 2 (2.0) (tied p < 0.02) and the forced expiratory volume in 1 s (FEV₁) increased from 72.0 (38.4) to 76.5 (52)% (p < 0.02). Energy intake improved (92.3 (14.5) to 117.0 (28.5)%; tied p < 0.02), as did weight for height (W/H; 90 (9.4) to 94 (8.5)%; tied p = 0.043). In the CF control patients the number of infections (2.0 (2.0)), energy intake (116 (43.3)%) and nutritional status remained stable (W/H 99 (17.2)%), but pulmonary function decreased significantly (ΔFEV₁ loss of 2.0 (8.0)%). There was a significantly different evolution for the change in forced vital capacity (p < 0.004) and ΔFEV₁ (p < 0.001) between supplemented and control patients. Conclusions: Analysis of the clinical data on Zn supplementation in CF showed beneficial effects in Zn-deficient CF patients. These results must be confirmed in a prospective double-blind randomized control trial.

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In this study the plasma lipid and apoprotein concentrations have been assayed in 80 full-term newborns, at 0, 7 and 30 days of life, and the data have been analyzed as a function of the composition of the diet. The total cholesterol, HDL cholesterol, the apo A-I, A-II and B protein concentrations were followed in 4 groups of infants receiving respectively breast-feeding, adapted formulae I, II with a P/S ratio close to that of maternal milk and a formula III enriched with polyunsaturated fatty acids. After 7 and 30 days the infants receiving the adapted formulae I and II have plasma lipid and apoprotein values similar to those of the breast-fed infants indicating a parallel evolution of the lipids and apoproteins in the three groups. The lipid and apoprotein patterns were significantly different in the group of infants receiving a diet enriched with polyunsaturated fatty acids. The total and VLDL-LDL cholesterol and the apo B protein concentrations are significantly lower than in the breast-fed infants after 7 days, and these differences become more pronounced after 30 days. These results suggest that the fatty acid composition of the diet influences the lipid and lipoprotein synthesis in newborns, specially by decreasing the lipid and apoprotein concentrations of the VLDL-LDL fraction.

ABSTRACT. In this study the lipid and apoprotein profiles were investigated in newborns at 0, 7, and 30 days of life. The plasma lipoproteins were separated both by ultracentrifugation and gel filtration in order to compare the patterns obtained by the two techniques. At birth, the apo E concentration is comparable to that measured in adults, but its distribution among lipoproteins is significantly different as more than 80% of the plasma apo E belongs to high-density lipoproteins (HDL). At 7 and 30 days the plasma apo E concentrations are close to the values at birth, but a significant redistribution occurs from HDL to very low-density lipoproteins. By analogy with apo B, the plasma apo CIII concentration is low at birth and increases between 0 and 7 days by a factor of about two. Plasma triglycerides increase significantly during the first week of life so that the apo CIII increase is most pronounced in very low-density lipoproteins. These lipoproteins therefore become enriched in apo E, apo CIII and triglycerides between 0 and 7 days. At birth, a distinct HDL fraction, enriched in apo E, apo A11 and cholesterol (HDLE), could be detected. To compensate for the low LDL levels, this HDLE fraction might function as an additional source for cholesterol delivery to peripheral tissues via the apo (B, E) receptor. At later age, low-density lipoprotein synthesis is enhanced, apo E is transferred to very low-density lipoproteins, and cholesterol delivery via the HDL, becomes less important. These data demonstrate that significant differences occur in the plasma concentration and distribution of the apo CIII and E proteins during the initial period of life, and that these apoproteins fulfill an important metabolic role. (Pediatr Res 20: 324-328, 1986) Abbreviations HDL, high-density lipoproteins VLDL, very low-density lipoproteins LDL, low-density lipoproteins During the perinatal period, major shifts in nutritional supply cause changes in substrate utilization by the fetus and newborn. Unimpeded substrate flow from placenta to fetus is required to meet the energy requirements for growth and for fuel storage, primarily of glycogen and fat. During the intra-and postpartum periods, this constant flow is interrupted so that glycogen is required to maintain serum glucose levels. Glycogen stores are then depleted and active glycogenesis starts. In the perinatal period, fatty acid and ketone body oxidation become important energy sources, and during this period an adaptation to a high fat milk diet becomes therefore necessary.These adaptations are controlled by changes in substrate flow and hormonal milieu of the fetus and newborn. Such changes n substrate result in rapid shifts in the synthesis and metabolism of lipid transporting particles, whose composition then changes from that before birth.In newborns, plasma lipid and lipoprotein patterns also are significantly different from those observed in adults, both in their concentration and distribution. Newborn plasma lipoproteins consist mostly of HDL, while VLDL and LDL are...

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