Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0029713 (immaturity)
 4,335 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Although extensive data are available on the impact of nutrient and protein administration on growth, plasma amino acids, and nitrogen balance in the newborn and growing infants, relatively few studies have carefully examined the dynamic aspects of protein metabolism in vivo and particularly in the micropremie or ELBW infant. These studies show that the very preterm infants, either because of immaturity or because of the intercurrent illness, have high rates of protein turnover and protein breakdown. This high rate of proteolysis is not as responsive to nutrient administration. Intervention strategies aimed at promoting nitrogen accretion, such as insulin, human growth hormone, or glutamine, have not thus far resulted in enhanced protein accretion and growth. This may be, in part, due to limitations in delivery of adequate calorie and nitrogen.
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PMID:Protein metabolism in the extremely low-birth weight infant. 1069 May 63

The pathogenesis of necrotizing enterocolitis (NEC) presumptively is due to an inappropriate intestinal epithelial immunologic response of immature gut to luminal stimuli. Glutamine is essential for intestinal crypt cell proliferation and enhances the cellular response to growth factors. We aimed to test the hypothesis that the supplementation of enteral feedings with glutamine may stimulate an immature intestine and decrease the intestinal inflammatory change in NEC. Immediately after birth, the neonatal rats were weighed and randomized into one of four treatment groups. Group 1 consisted of rats whom were breast-fed. Group 2 (NEC group) consisted of neonates whom were fed with a special rodent formula. Rats in groups 3 and 4 were fed in a similar fashion to those in group 2, and glutamine 0.3 mg/kg per day and dexamethasone 0.5 mg/kg per day were added to their formula, respectively. The neonatal rats were weighed and killed on day 4: the last 4 cm of terminal ileum was harvested for morphological studies and detection of nitrite and nitrate levels in tissue. The animals in the NEC group showed various degrees of inflammatory changes similar to clinical NEC. The inflammatory changes of the intestine appeared to be attenuated in both glutamine- and steroid-treated animals compared to those in the NEC group. Only steroid treatment decreased the tissue levels of these nitrogen oxides that were increased in rats in the NEC group. We herein provide evidence that maturational agents such as glutamine and dexametasone can attenuate the local intestinal inflammatory damage in experimental NEC. These findings support the hypothesis that the gut immaturity in premature infants represents a risk factor for NEC.
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PMID:Enteral glutamine supplementation and dexamethasone attenuate the local intestinal damage in rats with experimental necrotizing enterocolitis. 1455 27

Necrotizing enterocolitis (NEC) is one of the most critical morbidities in preterm infants. The incidence of NEC is 7% in very-low-birth-weight infants, and its mortality is 15 to 30%. Infants who survive NEC have various complications, such as nosocomial infection, malnutrition, growth failure, bronchopulmonary dysplasia, retinopathy of prematurity, and neurodevelopmental delays. The most important etiology in the pathogenesis of NEC is structural and immunological intestinal immaturity. In preterm infants with immature gastrointestinal tracts, development of NEC may be associated with a variety of factors, such as colonization with pathogenic bacteria, secondary ischemia, genetic polymorphisms conferring NEC susceptibility, anemia with red blood cell transfusion, and sensitization to cow milk proteins. To date, a variety of preventive strategies has been accepted or attempted in clinical practice with regard to the pathogenesis of NEC. These strategies include the use of breast feeding, various feeding strategies, probiotics, prebiotics, glutamine and arginine, and lactoferrin. There is substantial evidence for the efficacy of breast feeding and the use of probiotics in infants with birth weights above 1,000 g, and these strategies are commonly used in clinical practice. Other preventive strategies, however, require further research to establish their effect on NEC.
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PMID:An update on necrotizing enterocolitis: pathogenesis and preventive strategies. 2223 29

Glutamine may have benefits during immaturity or critical illness in early life but its effects on outcome end hardpoints are controversial. Our aim was to review randomized studies on glutamine supplementation in pups, infants, and children examining whether glutamine affects outcome. Experimental work has proposed various mechanisms of glutamine action but none of the randomized studies in early life showed any effect on mortality and only a few showed some effect on inflammatory response, organ function, and a trend for infection control. Although apparently safe in animal models (pups), premature infants, and critically ill children, glutamine supplementation does not reduce mortality or late onset sepsis, and its routine use cannot be recommended in these sensitive populations. Large prospectively stratified trials are needed to better define the crucial interrelations of "glutamine-heat shock proteins-stress response" in critical illness and to identify the specific subgroups of premature neonates and critically ill infants or children who may have a greater need for glutamine and who may eventually benefit from its supplementation. The methodological problems noted in the reviewed randomized experimental and clinical trials should be seriously considered in any future well-designed large blinded randomized controlled trial involving glutamine supplementation in critical illness.
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PMID:Glutamine randomized studies in early life: the unsolved riddle of experimental and clinical studies. 2301 24

Due to transient gut immaturity, most very preterm infants receive parenteral nutrition (PN) in the first few weeks of life. Yet providing enough protein and energy to sustain optimal growth in such infants remains a challenge. Extrauterine growth restriction is frequently observed in very preterm infants at the time of discharge from hospital, and has been found to be associated with later impaired neurodevelopment. A few recent randomized trials suggest that intensified PN can improve early growth; whether or not such early PN improves long-term neurological outcome is still unclear. Several other questions regarding what is optimal PN for very preterm infants remain unanswered. Amino acid mixtures designed for infants contain large amounts of branched-chain amino acids and taurine, but there is no consensus on the need for some nonessential amino acids such as glutamine, arginine, and cysteine. Whether excess growth in the first few weeks of life, at a time when very preterm infants receive PN, has an imprinting effect, increasing the risk of metabolic or vascular disease at adulthood continues to be debated. Even though uncertainty remains regarding the long-term effect of early PN, it appears reasonable to propose intensified initial PN. The aim of the current position paper is to review the evidence supporting such a strategy with regards to the early phase of nutrition, which is mainly covered by parenteral nutrition. More randomized trials are, however, needed to further support this type of approach and to demonstrate that this strategy improves short- and long-term outcome.
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PMID:Parenteral nutrition for preterm infants: Issues and strategy. 2965 25