Breast Milk for Preterm Multiples: More Proteins, Less Lactose.

Exclusive breastfeeding is currently recommended until at least 6 months of postnatal age, due to maternal breast milk (BM) unique composition and beneficial properties. In fact, BM modifies itself according to gestational age (GA) at birth, adapting its composition to neonatal requests during lactation. Multiple births represent about 3% of the whole pregnancies; such neonates result more vulnerable than full-term newborns, due to lower GA and birth weight (BW) and the higher incidence of perinatal complications. Although an adequate nutrition is fundamental for twins and other multiples, studies on this topic are lacking. We collected and analyzed BM from mothers of 19 twins and 5 triplets showing GA < 33 weeks and BW < 1500 g, comparing it to a control group of 28 preterm singletons. As a result, at GA ≤ 28 weeks, we observed that protein content is higher in BM for multiples (1.53 vs. 1.29 g per 100 ml), lactose concentration is greater in BM for singletons (6.72 vs. 6.34 g per 100 ml) and GA results the most relevant factor influencing BM protein composition. BM for multiples results higher in proteins and lower in lactose, if compared with singleton's samples; this could promote and sustain growth and organ development in this vulnerable category. BM from multiples shows a trophic and immunologic role, since these neonates often show lower GA and BW instead of singletons. These findings could help in optimizing nutritional strategies and improving BM individualized fortification.

Comparative cytogenetics in four species of Palinuridae: B chromosomes, ribosomal genes and telomeric sequences.

The evolutionary pathway of Palinuridae (Crustacea, Decapoda) is still controversial, uncertain and unexplored, expecially from a karyological point of view. Here we describe the South African spiny lobster Jasus lalandii karyotype: n and 2n values, heterochromatin distribution, nucleolar organizer region (NOR) location and telomeric repeat structure and location. To compare the genomic and chromosomal organization in Palinuridae we located NORs in Panulirus regius, Palinurus gilchristi and Palinurus mauritanicus: all species showed multiple NORs. In J. lalandii NORs were located on three chromosome pairs, with interindividual polymorphism. In P. regius and in the two Palinurus species NORs were located on two chromosome pairs. In the two last species 45S ribosomal gene loci were also found on B chromosomes. In addition, the nature and location of telomeric repeats were investigated by FISH in J. lalandii, P. gilchristi, P. mauritanicus Palinurus elephas, and P. regius (Palinuridae, Achelata), and in Scyllarus arctus (Scyllaridae, Achelata): all these Achelata species showed the (TTAGG)n pentameric repeats. Furthermore, in J. lalandii these repeats occurred in all the telomeres and in some interstitial chromosomal sites, associated with NORs.

Chromosome Mapping of 5S Ribosomal Genes in Indo-Pacific and Atlantic Muraenidae: Comparative Analysis by Dual Colour Fluorescence In Situ Hybridisation.

The Muraenidae is one of the largest and most complex anguilliform families. Despite their abundance and important ecological roles, morays are little studied, especially cytogenetically, and both their phylogenetic relationships and the taxonomy of their genera are controversial. With the aim of extending the karyology of this fish group, the chromosomal mapping of the 5S ribosomal gene family was performed on seven species belonging to the genera Muraena and Gymnothorax from both the Atlantic and Pacific oceans. Fluorescence in situ hybridisation (FISH) experiments were realized using species-specific 5S rDNA probes; in addition, two-colour FISH was performed to investigate the possible association with the 45S ribosomal gene family. Multiple 5S rDNA clusters, located either in species-specific or in possibly homoeologous chromosomes, were found. Either a syntenic or different chromosomal location of the two ribosomal genes was detected. Our results revealed variability in the number and location of 5S rDNA clusters and confirmed a substantial conservation of the number and location of the 45S rDNA.

Individualized fortification of breast milk in 41 Extremely Low Birth Weight (ELBW) preterm infants.

BACKGROUND: The use of breast milk presents numerous early and long-term advantages for ELBW preterms. However, breast milk without fortification does not cover the high nutritional needs of such patients. The aim of our study was to assess the effect of individualized fortification of breast milk on the growth of ELBWs hospitalized in a neonatal intensive care unit (NICU). METHODS: Retrospective single-center observational study. RESULTS: We assessed the growth of 41 consecutive ELBWs (21 females, 20 males) with gestational ages between 23 and 30 weeks (mean GA 26.31±1.8) fed with breast milk in an individualized way. The rate of growth as the mean weight increase with breast milk fortification was 16.04±3.13 g/kg/day, more than the growth of the fetus in the uterus (~15 g/kg/day). This result was confirmed also among the ELBWs of lower GA. However, only 24.4% of all the ELBWs at the time of discharge from the NICU presented an appropriate weight for their gestational age. No cases of Necrotizing Enterocolitis (NEC) were observed. CONCLUSIONS: Despite high growth velocity, the ELBWs failed to remain in the same percentiles of birth and, at discharge, only 27.7% had a weight of >10 centiles. Further studies are needed to improve growth during early critical phases of development.

H63D mutation in the HFE gene increases iron overload in beta-thalassemia carriers.

BACKGROUND AND OBJECTIVES: Hereditary hemochromatosis (HH) is an autosomal recessive disorder of iron metabolism. The HFE gene implicated in this disorder has been identified on chromosome 6 (6p21.3). The most prevalent mutation in HH patients changes the 282 cysteine residue to tyrosine (C282Y). The role of a second mutation which changes the 63 histidine to aspartic acid (H63D) in iron overload has been controversial. The aim of this study was to evaluate the effect of the H63D mutation on the ferritin levels of beta-thalassemia carriers. DESIGN AND METHODS: beta-thalassemia carriers have a tendency to increase iron absorption because of mild anemia and slightly increased erythropoiesis. Differences in ferritin levels between homozygotes for H63D and wild type may indicate a modulator effect of the HFE mutation on iron absorption. We studied 152 healthy males, heterozygous for beta-thalassemia. Serum ferritin was measured by chemiluminescence. H63D genotypes were determined by digestion of polymerase chain reaction (PCR) products with MboI restriction enzyme. RESULTS: Forty-five subjects were H63D heterozygotes and four subjects were H63D homozygotes. Ferritin levels were (mean +/- SD): 250 +/- 138 microg/L in homozygotes for the wild type H/H; 295 +/- 186 microg/L in H/D heterozygotes; and 389 +/- 75 microg/L in homozygotes for the mutation D/D. The difference in ferritin values between H/H and D/D is statistically significant (p=0.022). INTERPRETATION AND CONCLUSIONS: beta-thalassemia carriers who are homozygotes for the H63D mutation have higher ferritin levels than beta-thalassemia carriers with the H/H genotype, suggesting that the H63D mutation may have a modulating effect on iron absorption.