Search

Background: Medical devices such as perfusion materials in polyvinyl chloride may contain di(2-ethylhexyl)phthalate (DEHP). Several studies have questioned the harmlessness of phthalates, which have been shown to have toxic effects on the reproductive system and general development. This study was designed to assess DEHP exposure in infants and children benefitting from cyclic parenteral nutrition (PN). The results are compared with those obtained from children used as controls and receiving no PN, to estimate the potential risk to this pediatric population, taking into account exposure levels and already published data., Methods: Plasmatic concentrations of DEHP were assessed by high-performance liquid chromatography from blood samples taken from 22 children at the start and finish of a 12-hour cyclic PN period and compared with those obtained from 20 control children of comparable age and gender., Results: After a 12-hour cyclic PN period, DEHP migration varied widely among the patients. The concentrations were not quantifiable in 4 children at the start of PN. In 1 child, they were quantifiable neither at the start nor at the end of PN. However, for 17 children, DEHP concentrations were quantifiable at the start of PN and were very variable from one child to another. At the end, DEHP concentrations had significantly but variably increased in these children. No trace of DEHP was found in the blood samples from 20 healthy controls., Conclusion: Considering published data on phthalate toxicity, it would appear advisable to encourage the use of medical devices that are either phthalate or DEHP free.

Background: Plasticizers such as di(2-ethylhexyl) phthalate (DEHP) are added to polyvinyl chloride (PVC) to confer flexibility. However, DEHP is associated with reproductive disorders in humans. Because of its noncovalent bond to the PVC matrix, this plasticizer tends to leach easily. Infants and children undergoing cyclic, long-term parenteral nutrition (PN) could be particularly at risk of potential toxicity from DEHP due to regular exposure. Malondialdehyde (MDA) is one of the most commonly used markers of free radical activity. The purpose of this study was to investigate how long-term exposure to phthalate affects the plasmatic rate of MDA., Methods: Studies were performed on 7 randomized infants and children on regular cyclic, long-term PN, and the results were compared with those of 5 nontreated infants. The circulating concentrations of DEHP in children and infants during the PN therapy were measured by high-performance liquid chromatography. The concentrations were assessed before and after the PN session. In the same way, plasma MDA concentrations were measured., Results: The circulating concentrations of DEHP before and after a 10- to 11-hour cyclic PN treatment in 7 infants and children under regular perfusion ranged widely, showing a significant increase after the treatment among all the patients. The same phenomenon observed with the rate of MDA showed that the 2 events are closely dependent. Therefore, long-term exposure to DEHP during cyclic PN raised plasma MDA levels, indicating increased oxidative stress., Conclusion: Long-term exposure to DEHP during PN increased free radical activity in vivo.

Microdesmis keayana (Pandaceae) is an African tropical plant whose roots are used in traditional medicine for erection impairment but the compounds responsible for its action are unknown. Two major alkaloids recently isolated from the roots of M. keayana, keayanidine B and keayanine, were tested for vasorelaxing properties using isolated rat aortic rings precontracted by phenylephrine to confirm its traditional use. Influence of the alkaloids on the endothelial production of endothelial nitric oxide synthase (eNOS) was measured by quantitative polymerase chain reaction (QPCR) analysis. Scavenging activities were assessed versus 1,1-diphenyl-2-picrylhydrazyle (DPPH) and reactive oxygen species (ROS) such as superoxide anion (O(2)(*-) and hydrogen peroxide (H(2)O(2)) in cell-free and cellular systems. The results showed that keayanidine B and keayanine had significant vasorelaxing properties. This effect could be due to their strong antioxidant activity versus O(2)(*-) and H(2)O(2) and to their stimulation of eNOS mRNA expression. Therefore these alkaloids could indirectly stimulate NO production in the vascular bed and would explain the traditional use of M. keayana in erectile dysfunction., ((c) 2008 John Wiley & Sons, Ltd.)

The neurosedative and antioxidative properties of some major compounds isolated from a citral chemotype of Lippia alba were investigated. Binding assays were performed on two CNS inhibitory targets: benzodiazepine and GABA(A) receptors. The most active compound was luteolin-7-diglucuronide, with half maximal inhibitory concentrations (IC(50)) of 101 and 40 microm, respectively. Fifteen compounds isolated from Lippia alba were tested for their radical scavenging capacities against DPPH. Four of the major compounds (verbascoside, calceolarioside E, luteolin-7-diglucuronide and theveside) were also tested for their antioxidant activity against superoxide radical-anion in cell-free (hypoxanthine-xanthine oxidase) and cellular (PMA-stimulated neutrophil granulocytes) systems.