Objective To examine the effects of sucrose on pain and biochemical markers of adenosine trisphosphate(ATP) degradation and oxidative stress in preterm neonates experiencing a clinically required heel lance. Study design Preterm neonates that met study criteria (n=131) were randomized into three groups: (1) control; (2) heel lance treated with placebo and non-nutritive sucking (NNS); and (3) heel lance treated with sucrose and NNS. Plasma markers of ATP degradation (hypoxanthine, xanthine and uric acid) and oxidative stress (allantoin) were measured before and after the heel lance. Pain was measured using the Premature Infant Pain Profile (PIPP). Data were analyzed using repeated measures ANOVA and Spearman rho. Results We found significant increases in plasma hypoxanthine and uric acid over time in neonates who received sucrose. We also found a significant negative correlation between plasma allantoin concentration and PIPP in a subgroup of neonates who received sucrose. Conclusion A single dose of oral sucrose, given before heel lance, significantly increased ATP utilization and oxidative stress in premature neonates. Because neonates are given multiple doses of sucrose per day, randomized trials are needed to examine the effect of repeated sucrose administration on ATP degradation, oxidative stress and cell injury.

In this report, we demonstrate a rapid, simple, and green method for synthesizing silver-gold (Ag-Au) bimetallic nanoparticles (BNPs). We used a novel modification to the galvanic replacement reaction by suspending maltose coated silver nanoparticles (NPs) in ≈ 2% aqueous solution of EO100PO65EO100 (Pluronic F127) prior to HAuCl4 addition. The Pluronic F127 stabilizes the BNPs, imparts biocompatibility, and mitigates the toxicity issues associated with other surfactant stabilizers. BNPs with higher Au:Ag ratios and, subsequently, different morphologies were successfully synthesized by increasing the concentration of gold salt added to the Ag NP seeds. These BNPs have enhanced catalytic activities than typically reported for monometallic Au or Ag NPs (∼ 2–10 fold) of comparable sizes in the sodium borohydride reduction of 4-nitrophenol. The 4-nitrophenol reduction rates were highest for partially hollow BNP morphologies.

Background Germinal matrix intraventricular hemorrhage (IVH) is the most common type of intracranial hemorrhage observed in preterm neonates. It is a precursor of poor neurocognitive development, cerebral palsy and death. The pathophysiology is not well defined, but damage to the fragile germinal matrix vasculature may be due to free radicals generated during inflammation and as a consequence of ischemia followed by reperfusion. Assessment of the oxidative stress status in these infants is therefore important. Urinary allantoin concentration was measured in preterm neonates as a marker of oxidative stress associated with IVH. Study design Urine was collected from 44 preterm neonates at four time points between 24 and 72 hours of life (HOL) and the allantoin content was determined by gas chromatography mass spectrometry (GCMS). Records were retrospectively reviewed and the incidence and severity of IVH was categorized as follows: no IVH (n=24), mild (grade 1-2) IVH (n=13) and severe (grade 3-4) IVH (n=7). Results Neonates with severe IVH showed significantly elevated allantoin levels vs subjects with no IVH from 36 HOL (0.098±0.013µmol and 0.043±0.007µmol, respectively, p=.002). The allantoin concentration remained elevated even at 72 HOL (0.079±0.014µmol and 0.033±0.008µmol, respectively, p=.021). There were no significant differences in allantoin levels in the no IVH and mild IVH groups. IVH was diagnosed by head imaging on average at about 11th post-natal day. Conclusion Urinary allantoin levels were significantly elevated during the first 3 days of life in the neonates subsequently diagnosed with severe IVH, suggesting that oxidative stress might be a crucial factor in IVH pathogenesis. Further studies are needed to assess the usefulness of urinary allantoin in early identification of preterm infants at risk for or with severe IVH, and monitoring of the response to interventions designed to prevent or treat it.

Advances in nanotechnology provide opportunities for the prevention and treatment of periodontal disease. While physicochemical properties of Ag containing nanoparticles (NPs) are known to influence the magnitude of their toxicity, it is thought that nanosilver can be made less toxic to eukaryotes by passivation of the NPs with a benign metal. Moreover, the addition of other noble metals to silver nanoparticles, in the alloy formulation, is known to alter the silver dissolution behavior. Thus, we synthesized glutathione capped Ag/Au alloy bimetallic nanoparticles (NPs) via the galvanic replacement reaction between maltose coated Ag NPs and chloroauric acid (HAuCl4) in 5% aqueous triblock F127 copolymer solution. We then compared the antibacterial activity of the Ag/Au NPs to pure Ag NPs on Porphyromonas gingivalis W83, a key pathogen in the development of periodontal disease. Only partially oxidized glutathione capped Ag and Ag/Au (Au:Ag≈0.2) NPs inhibited the planktonic growth of P. gingivalis W83. This effect was enhanced in the presence of hydrogen peroxide, which simulates the oxidative stress environment in the periodontal pocket during chronic inflammation.

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