RESUMEN
The initial colonization of the intestine represents one of the most profound immunological exposures faced by the newborn. During the first three years of life, the intestinal microbial composition undergoes significant changes. At birth, the digestive tract is rapidly colonized by microorganisms of maternal and environmental origins. Microbiota's composition is influenced by various factors, including the mode of delivery, gestational age, type of feeding, and medication use. Through the current study, we specifically focused on elucidating the dynamics of gut microbiota colonization within the first three weeks of life of infants, shedding light on this critical phase of development. A prospective cohort study involving 29 preterm infants was conducted from January to September 2021 at the National Reference Center for Neonatology and Nutrition, in collaboration with the research laboratory of Children's Hospital at the University Hospital Center Ibn Sina in Rabat. Stool samples were collected from each infant's diapers into a sterile tube and send for laboratory analysis. A total of 203 stool samples were collected. For each newborn, one stool sample was obtained within the first 48 h after birth, followed by two samples per week over a period of three weeks. The microbial compositions of these samples were analyzed using real-time polymerase chain reaction.
RESUMEN
Vitamin D deficiency is a health problem in both developed and developing countries. The aim of this study was to determine the effect of multi-vitamin fortified milk consumption on vitamin D status among children living in the mountainous region of Morocco. Children aged 7 to 9 years (n = 239; 49% of girls vs 51% of boys) participated in a double-blind longitudinal study, where they were divided in 2 groups: a fortified group that received daily 200 mL of fortified ultra-high-temperature (UHT) milk enriched with 3 µg of vitamin D3 and a nonfortified group that received 200 mL of nonfortified UHT milk with a natural abundance of vitamin D3 (about 1.5 µg). Blood samples were collected 3 times (at baseline, then at the fourth and ninth months). The average weight, height, and z score of body mass index for age of participants were 22.8 ± 2.6 kg, 121.5 ± 5.2 cm, and -0.2 ± 0.6 kg/m2, respectively. At baseline, 47.5% of children had a concentration of 25-hydroxyvitamin D below 50 nmol/L. At the end of the study the prevalence of vitamin D <50 nmol/L decreased significantly by 37.6% in the fortified group. These results reveal prevalent vitamin D insufficiency (<50 nmol/L) during winter among rural Moroccan school-aged children, which seems to be better improved by consuming the fortified milk instead of the nonfortified one.