RESUMEN
Adequate nutrition is extremely crucial for the growth and development of preterm, small-for-gestational-age (SGA) infants owing to an increased risk of postnatal growth failure and poor neurodevelopmental outcome. Despite the beneficial properties of human milk (HM), it should be fortified to prevent extrauterine growth restriction; however, fortification of HM with a bovine-based human milk fortifier (BHMF) may induce feeding intolerance (FI) and necrotizing enterocolitis in preterm newborns. Herein, we have described the nutritional management of a preterm SGA newborn with intolerance to BHMF. A male infant was born at a gestational age of 32 weeks and 5 days, SGA weighing 1,490 grams (< 10th percentile). During BHMF use, he presented with symptoms of FI including abdominal distention, increased gastric residuals, and delayed enteral feeding advancement. Therefore, HM was fortified with carbohydrate powder, whey protein powder, and medium-chain triglycerides oil instead of BHMF to prevent FI and promote weight gain. Caloric density of feeds was increased once every 3 or 4 days by approximately 5 kcal/kg/day until an intake of 100 kcal/kg/day was achieved. Subsequently, his caloric and protein intake increased, growth rate improved, and full enteral feeding was achieved without any further symptom of FI. In conclusion, the symptoms of FI with BHMF in a preterm SGA neonate improved with the administration of a macronutrient fortified HM without compromising his enteral feed advancements, growth rate, and energy or protein intake.
RESUMEN
Adequate nutrition is extremely crucial for the growth and development of preterm, small-for-gestational-age (SGA) infants owing to an increased risk of postnatal growth failure and poor neurodevelopmental outcome. Despite the beneficial properties of human milk (HM), it should be fortified to prevent extrauterine growth restriction; however, fortification of HM with a bovine-based human milk fortifier (BHMF) may induce feeding intolerance (FI) and necrotizing enterocolitis in preterm newborns. Herein, we have described the nutritional management of a preterm SGA newborn with intolerance to BHMF. A male infant was born at a gestational age of 32 weeks and 5 days, SGA weighing 1,490 grams (< 10th percentile). During BHMF use, he presented with symptoms of FI including abdominal distention, increased gastric residuals, and delayed enteral feeding advancement. Therefore, HM was fortified with carbohydrate powder, whey protein powder, and medium-chain triglycerides oil instead of BHMF to prevent FI and promote weight gain. Caloric density of feeds was increased once every 3 or 4 days by approximately 5 kcal/kg/day until an intake of 100 kcal/kg/day was achieved. Subsequently, his caloric and protein intake increased, growth rate improved, and full enteral feeding was achieved without any further symptom of FI. In conclusion, the symptoms of FI with BHMF in a preterm SGA neonate improved with the administration of a macronutrient fortified HM without compromising his enteral feed advancements, growth rate, and energy or protein intake.
RESUMEN
Melanin is a pigment produced from tyrosine in melanocytes. Although melanin has a protective role against UVB radiation-induced damage, it is also associated with the development of melanoma and darker skin tone. Tyrosinase is a key enzyme in melanin synthesis, which regulates the rate-limiting step during conversion of tyrosine into DOPA and dopaquinone. To develop effective RNA interference therapeutics, we designed a melanin siRNA pool by applying multiple prediction programs to reduce human tyrosinase levels. First, 272 siRNAs passed the target accessibility evaluation using the RNAxs program. Then we selected 34 siRNA sequences with ΔG ≥−34.6 kcal/mol, i-Score value ≥65, and siRNA scales score ≤30. siRNAs were designed as 19-bp RNA duplexes with an asymmetric 3′ overhang at the 3′ end of the antisense strand. We tested if these siRNAs effectively reduced tyrosinase gene expression using qRT-PCR and found that 17 siRNA sequences were more effective than commercially available siRNA. Three siRNAs further tested showed an effective visual color change in MNT-1 human cells without cytotoxic effects, indicating these sequences are anti-melanogenic. Our study revealed that human tyrosinase siRNAs could be efficiently designed using multiple prediction algorithms.