Enhancing sensory experiences for very preterm infants in the NICU: an integrative review

OBJECTIVE

Very preterm infants hospitalized in the neonatal intensive care unit (NICU) experience alterations in sensory experiences. Defining types, timing and frequency of sensory-based interventions that optimize outcomes can inform environmental modifications. The objective of this study was to conduct an integrative review on sensory-based interventions used with very preterm infants in the NICU to improve infant and parent outcomes.

STUDY DESIGN

The data sources include MEDLINE, CINAHL, Cochrane Library and Google Scholar. Studies were identified that used sensory-based interventions in the NICU with preterm infants born ⩽32 weeks gestation, were published in a peer-reviewed journal between 1995 and 2015, and measured outcomes related to infant and parent outcomes. Studies were extracted from electronic databases and hand-searched from identified reference lists.

RESULTS

Eighty-eight articles were identified (31 tactile, 12 auditory, 3 visual, 2 kinesthetic, 2 gustatory/olfactory and 37 multimodal). There was evidence to support the use of kangaroo care, music and language exposure, and multimodal interventions starting at 25 to 28 weeks postmenstrual age. These interventions were related to better infant development and lower maternal stress, but not all findings were consistent. Limitations included lack of consistent outcome measures, study quality and gaps in the literature.

CONCLUSIONS

Most research identified interventions that were done for short periods of time. It is unclear what the potential is for improving outcomes if positive sensory exposures occur consistently throughout NICU hospitalization. Until more research defines appropriate sensory-based interventions to use with infants born very preterm in the NICU, information from this review can be combined with expert opinion and parent/family values to determine best practice.

Synergistic inhibition of cyclooxygenase-2 expression by vitamin E and aspirin

The use of aspirin in rheumatoid arthritis is limited since inhibition of the pro-inflammatory enzyme cyclooxygenase-2 occurs only at higher aspirin doses that are often associated with side effects such as gastric toxicity. Using a macrophage cell line (J774. 1A), the present study explores possible synergistic effects of aspirin and vitamin E on the expression and activity of cyclooxygenase-2. Lipopolysaccharide-induced prostaglandin E(2) formation was significantly reduced by aspirin (1-100 microM) or vitamin E (100-300 microM). When combined with vitamin E, aspirin-dependent inhibition of prostaglandin E(2) formation was increased from 59% to 95% of control. Likewise, lipopolysaccharide-induced cyclooxygenase-2 protein and mRNA expression were virtually abolished by the combined treatment of aspirin and vitamin E, whereas the two agents alone were only modestly effective. Vitamin C did not mimic the actions of vitamin E under these conditions, suggesting that redox-independent mechanisms underlie the action of vitamin E. In agreement with this, vitamin E and aspirin were without effect on lipopolysaccharide-induced translocation of the redox-sensitive transcription factor NF-kappa B. Our results show that co-administration of vitamin E renders cyclooxygenase-2 more sensitive to inhibition by aspirin by as yet unknown mechanisms. Thus, anti-inflammatory therapy might be successful with lower aspirin doses when combined with vitamin E, thereby possibly avoiding the side effects of the usually required high dose aspirin treatment.

The antioxidant defense protein ferritin is a novel and specific target for pentaerithrityl tetranitrate in endothelial cells

The organic nitrate pentaerithrityl tetranitrate (PETN) is known to exert long-term antioxidant and antiatherogenic effects by as yet unidentified mechanisms. In porcine aortic endothelial cells, a 24 h incubation with PETN (1-100 microM) or its metabolite pentaerithrityl trinitrate (PETriN) increased levels of the antioxidant protein ferritin up to three-fold over basal, whereas isosorbide dinitrate and isosorbide-5-mononitrate were without significant effect under these conditions. PETriN-induced ferritin expression was blocked by the NO scavenger PTIO but remained unaltered in the presence of ODQ, an inhibitor of soluble guanylyl cyclase. 8-Bromo cyclic GMP and dibutyryl cyclic GMP did not influence basal ferritin synthesis. The iron chelator desferrioxamine abolished ferritin induction by PETriN. Our results show that PETN or its active metabolite PETriN induce ferritin synthesis through NO- and iron-dependent but cyclic GMP-independent pathways. Increased activity of ferritin may contribute to, and at least in part explain, the specific antiatherogenic and antioxidant action of PETN.

Generators of brain electrical activity in patients with Wilson's disease

Electroencephalographic (EEG) generators were investigated in 13 patients suffering from hepatolenticular degeneration with and without neurological symptoms and in 13 healthy subjects for comparison by the use of FFT approximation. Quantitative assessment of motor deficits and psychiatric disturbances was correlated with EEG features. We found mainly an increase in delta activity, a decrease in alpha activity combined with a more posterior localisation of the EEG generators in the delta band and a more anterior one in the alpha band in patients compared with healthy controls. The localisation of the EEG generators in the patients with clinical apparent neurological symptoms were in all frequency bands more superficial compared with controls and patients without neurological symptoms. With longer duration of the disease, the lower the premorbid intelligence the more posterior was the delta EEG generator localised. Although the alpha EEG generator was more anteriorly localised with longer duration of the disease and more severe cognitive deficits, it was more superficial with more pronounced psychiatric symptoms, more severe cognitive deficits, lower premorbid intelligence and more pronounced motor disabilities. With more pronounced psychiatric symptoms and cognitive deficits, the beta EEG generator was more anteriorly localised. The present study demonstrated that a significant deviant EEG pattern exists between patients with and without clinical neurological symptoms and that stage-dependent alterations in psychiatric symptoms and cognitive ability are reflected on the EEG.

Lipopolysaccharide-induced expression of cyclooxygenase-2 in mouse macrophages is inhibited by chloromethylketones and a direct inhibitor of NF-kappa B translocation

In macrophages, cyclooxygenase-2 (COX-2) is induced by cytokines, mitogens, or endotoxin. The present study investigates whether inhibitors of the nuclear transcription factor NF-kappa B affect lipopolysaccharide (LPS)-mediated expression of COX-2 mRNA, protein, and activity in the macrophage cell line J774.1A. The activation of COX-2 was assessed by measuring the accumulation of prostaglandin (PG) E2 by radioimmunoassay. Expression of COX-2 mRNA and protein was detected by Northern and Western blot analysis, respectively. In the absence of LPS, mouse macrophages did not express COX-2 and generated low amounts of prostaglandin (PG) E2. Treatment of J774.1A with LPS (0.1-30 micrograms/ml) caused expression of COX-2 protein and activity. Induction of COX-2 activity along with the induction of COX-2 mRNA and protein by LPS was attenuated by the serine protease inhibitors N-alpha-tosyl-L-phenylalanine chloromethyl ketone (TPCK) and N-alpha-tosyl-L-lysine chloromethyl ketone (TLCK). A cell permeable peptide and a direct inhibitor of NF-kappa B translocation, SN50, attenuated the accumulation of PGE2 in cell supernatant in a concentration-dependent manner. Our results show that induction of COX-2 by LPS in macrophages involves activation of NF-kappa B and point to a possible therapeutic use of protease inhibitors in inflammatory processes.

Aspirin increases ferritin synthesis in endothelial cells: a novel antioxidant pathway

Aspirin has recently been shown to increase endothelial resistance to oxidative damage. However, the mechanism underlying aspirin-induced cytoprotection is still unknown. Using cultured cells, the present study investigates the effect of aspirin on the expression of ferritin, a cytoprotective protein that sequesters free cytosolic iron, the main catalyst of oxygen radical formation. In bovine pulmonary artery endothelial cells, aspirin at low antithrombotic concentrations (0.03 to 0.3 mmol/L) induced the synthesis of ferritin protein in a time- and concentration-dependent fashion up to 5-fold over basal levels, whereas ferritin H (heavy chain) mRNA remained unaltered. Aspirin-induced cytoprotection from hydrogen peroxide toxicity was mimicked by exogenous iron-free apoferritin but not iron-loaded ferritin, demonstrating the antioxidant function of newly synthesized ferritin under these conditions. Ferritin induction by aspirin was specific in that other nonsteroidal anti-inflammatory drugs such as salicylic acid, indomethacin, or diclofenac failed to alter ferritin protein levels. Aspirin-induced ferritin synthesis was abrogated in the presence of the iron chelator desferrioxamine, pointing to an interaction of aspirin with iron-responsive activation of ferritin translation. Together, our results suggest induction of ferritin as a novel mechanism by which aspirin may prevent endothelial injury in cardiovascular disease, eg, during atherogenesis.

Improved L-lysine yield with Corynebacterium glutamicum: use of dapA resulting in increased flux combined with growth limitation

The amino acid L-lysine is produced on a large scale using mutants of Corynebacterium glutamicum. However, as yet recombinant DNA techniques have not succeed in improving strains selected for decades by classic mutagenesis for high productivity. We here report that seven biosynthetic enzymes were assayed and oversynthesis of the dihydrodipicolinate synthase resulted in an increase of lysine accumulation from 220 mM to 270 mM. The synthase, encoded by dapA, is located at the branch point of metabolite distribution to either lysine or threonine and competes with homoserine dehydrogenase for the common substrate aspartate semialdehyde. When graded dapA expression was used, as well as quantification of enzyme activities, intracellular metabolite concentrations and flux rates, a global response of the carbon metabolism to the synthase activity became apparent: the increased flux towards lysine was accompanied by a decreased flux towards threonine. This resulted in a decreased growth rate, but increased intracellular levels of pyruvate-derived valine and alanine. Therefore, modulating the flux at the branch point results in an intrinsically introduced growth limitation with increased intracellular precursor supply for lysine synthesis. This does not only achieve an increase in lysine yield but this example of an intracellularly introduced growth limitation is proposed as a new general means of increasing flux for industrial metabolite over-production.

The nitric oxide donor SIN-1 protects endothelial cells from tumor necrosis factor-alpha-mediated cytotoxicity: possible role for cyclic GMP and heme oxygenase

In cultured endothelial cells, incubation with TNF-alpha (50 ng/ml) for 72 h markedly reduced viability of endothelial cells. A 6-h pre-incubation with the nitric oxide (NO) donor linsidomine (SIN-1, 10-150 microM) protected endothelial cells in a concentration-dependent manner and increased viability by up to 59% of control. The unmetabolized parent compound molsidomine and the NO-free metabolite of SIN-1 3-morpholinoiminoacetonitrile (SIN-1C) were without cytoprotective effect. Cytoprotection by SIN-1 was completely abolished by the NO scavenger 2-phenyl-4,4,5,5, -tetramethylimidazoline-1-oxyl-3-oxide (PTIO, 30 microM). A cytoprotective effect comparable to SIN-1 was observed when preincubating the cells with dibutyryl cyclic GMP (10-100 microM). Moreover, no protection by SIN-1 occurred in the presence of cycloheximide (1 microM) or 1H--1,2,4-oxadiazole-4, 3-a-quinoxalin-1-one (ODQ, 0.1 microM), a selective inhibitor of soluble guanylyl cyclase. Tin protoporphyrin-IX (SnPP, 25 microM), an inhibitor of heme oxygenase, was found to attenuate SIN-1-induced cytoprotection. Our results demonstrate that SIN-1 produces a long-term endothelial protection against cellular injury by TNF-alpha, presumably via a cyclic GMP-dependent pathway leading to up-regulation of protective proteins such as heme oxygenase.

Aspirin protects endothelial cells from oxidative stress--possible synergism with vitamin E

A 24-h incubation with hydrogen peroxide (0.65 mM) markedly reduced viability of cultured endothelial cells. Preincubation with aspirin (3-30 microM) protected endothelial cells from hydrogen peroxide-induced toxicity and increased viability in a concentration-dependent fashion by up to 64% of control. A similar protection was observed with D-alpha-tocopherol acetate (vitamin E, 3-30 microM). The cytoprotective effects of aspirin and vitamin E against hydrogen peroxide were overadditive suggesting different mechanisms of antioxidant action. In agreement with this, cytotoxicity induced by iron, the main catalyst of oxygen radical formation, was substantially reduced by aspirin but not vitamin E. These results show that aspirin protects endothelial cells from oxidative stress possibly via binding or chelation of free cytosolic iron. Moreover, a combination of aspirin and vitamin E might be useful for the prevention of endothelial injury in cardiovascular disease, e.g. during atherogenesis.

Ferritin may mediate SIN-1-induced protection against oxidative stress

In porcine aortic endothelial cells, a 20-h incubation with hydrogen peroxide (0.5 mM) markedly reduced the number of viable cells. A 6-h preincubation with linsidomine (SIN-1, 0.5 mM) protected endothelial cells from hydrogen peroxide-dependent cytotoxicity and increased the surviving endothelial cell fraction by 85%. This protection was associated with a 2.5-fold induction of ferritin heavy chain mRNA and ferritin protein by SIN-1. The nitric oxide donor glyceryl trinitrate was also found to induce transcriptional and translational expression of ferritin heavy chain. A protective effect comparable to SIN-1 was observed when preincubating the cells with iron-free apoferritin (1 mg/ml). These findings suggest that ferritin induction, presumably via release of nitric oxide, may be a mechanism underlying long-term cytoprotection by SIN-1 against oxidative stress.

Nitric oxide protects endothelial cells from tumor necrosis factor-alpha-mediated cytotoxicity: possible involvement of cyclic GMP

In cultured endothelial cells, incubation with TNF-alpha (50 ng/ml) for 48 h markedly reduced viability of endothelial cells. A 6 h preincubation with Sper/NO (0.03--1 microM) protected endothelial cells in a concentration-dependent manner and increased viability by 63% of control. The NO scavenger PTIO (30 microM) completely abolished cytoprotection by Sper/NO. A cytoprotective effect comparable to Sper/NO was observed when preincubating the cells with 8-bromo cyclic GMP (1-10 microM). Moreover, no protection by Sper/NO occurred in the presence of ODQ (0.1 microM), a selective inhibitor of soluble guanylyl cyclase. Our results demonstrate that NO produces a long-term endothelial protection against cellular injury by TNF-alpha, presumably via a cyclic GMP-dependent pathway.

Photoactivation of the nitric oxide donor SIN-1

This study investigates whether nitric oxide (NO) release from linsidomine (SIN-1), the active metabolite of the antianginal drug molsidomine, is light sensitive. A 9-h irradiation with polychromatic visible light increased the formation of nitrite (NO index metabolite) from SIN-1 (1 mM) by 61% as compared to control samples incubated in the dark. Under the same conditions (9-h irradiation) the concentration of oxygen decreased to 2% of control. However, oxygen consumption was substantially reduced when light was excluded (35% recovery after 9 h). These results show that irradiation with visible light markedly enhances the oxygen-dependent NO release from SIN-1. Thus, sydnonimines appear to be suitable model compounds for the development of photoactivatable NO donors.

Taking the jab out of needles

Typically, health professionals regard injections and venipuncture as routine for them and a minor nuisance for the patient. Yet for others, needles arouse dread and anxiety. This fear of needles may even lead some people to avoid dental and health care.

Children's venipuncture pain: influence of technical factors

Several aspects of venipuncture technique were evaluated to assess their relationship to reported pain. Subjects were 514 children aged 5-17 who had venipuncture performed by a technician in a hospital outpatient laboratory. A research assistant timed the duration of venipuncture and then obtained visual analogue pain scores from the children following venipuncture. Blood volume obtained from venipuncture was also measured. The technician who performed the procedure, amount of blood drawn, and time required to complete the venipuncture did not contribute to the prediction of children's pain. Age and anxiety, which were treated as covariates, were significant predictors of pain. The distribution of pain experienced by children was positively skewed and about one-third of children were above the mean pain score. From the results of this study, venipuncture pain can be recommended for the study of issues in children's pain. Further, the findings recommend the development and utilization of interventions to reduce children's venipuncture pain.