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Cognitive performance in 7- to 9-year-old preterm neonatal intensive-care survivors was compared with that in age-matched control children. Non-verbal memory span, spatial working-memory abilities, planning, set-shifting, and recognition memory for both spatial and patterned stimuli were assessed using the Cambridge Neuropsychological Testing Automated Battery. Relative to children in the control group, neonatal intensive-care unit (NICU) survivors demonstrated 25% more memory errors on the spatial working-memory task. Their use of strategy on this task was similar to a control group of 5-year-olds. Planning times on 'Tower of London' problems were long relative to those of term controls. NICU survivors demonstrated poorer pattern recognition as well as a shorter spatial memory span. The groups did not differ in visual-discrimination learning or in spatial-recognition memory. No specific neonatal risk factor accounted for the observed differences, although scores on the Neurobiological Risk Score (NBRS), a composite measure of neonatal risk, did predict several aspects of later task performance. Whether these data reflect a developmental delay in brain maturation in NICU survivors or the presence of a permanent information-processing deficit due to adverse neonatal events must be assessed through continued follow-up.

Context: Rural residents experience the same incidence of acute illness as urban populations and have higher levels of chronic illness. Overall, access to adequate rural health care is limited. Nurse practitioners (NPs) have been identified as safe, cost-effective providers in meeting these challenges in rural settings. Purpose: This replication study was conducted to examine NP perceptions of barriers to rural practice in Minnesota. Findings were compared to earlier studies to examine issues that have persisted over time. Methods: A Barriers to Practice checklist was mailed to NPs from the database of the Board of Nursing of a midwestern state. Rural NPs (n = 191) identified and described barriers to practice and rated the overall restrictiveness of their practice. Findings: Barriers to practice were perceived to be prevalent. Persisting barriers continued to stand in the way of full utilization of NP roles. Lack of understanding of NP roles on the part of the public and other health professionals has been particularly problematic over time. Key issues in 2001 were low salaries, lack of adequate office space, and a limited peer network. Perceived restrictiveness of the practice climate, gauged as somewhat restrictive, remained unchanged between 1996 and 2001. Conclusions: NPs have an excellent history of meeting rural primary health care needs. Enhancing the NP work environment could prove instrumental to retaining these professionals in the work force and thereby contribute to improved access and quality of care in underserved rural communities.

During the last years allergenic substances in food have gained more and more attention. Stricter rules for a peanut free food labelling demand a peanut contamination less than 5 ppm. The maintenance of a high quality of food products with regards to allergenic exposure is preferable warranted with rapid tests that can be utilized as an aid for suppliers to control raw materials, to avoid cross contamination during production and to check the final products. A rapid sandwich peanut ELISA was developed, which covers a measuring range of 2.5-20 ppm peanut (detection limit of 1.5 ppm). This test was successfully evaluated in an independent study under the supervision of the AOAC Research Institute, getting the AOAC certificate No. 030404. In-house validation and independent validation data demonstrate the reliability, accuracy and precision of the test.

Formation of metabolic intermediate (MI) complexes was studied with the enantiomers of amphetamine, 1-phenyl-2-pentanamine, N-hydroxyamphetamine, and 2-nitroso-1-phenylpropane (the C-nitroso analogue of amphetamine). Three different enzyme systems were used; liver microsomes from phenobarbital pretreated rats and two reconstituted systems containing the P450 2B1 and P450 2C11 forms of cytochrome P-450. Enantioselective complex formation in microsomes was shown for the amines and the nitroso compound, but not for the hydroxylamine. The highly purified P450 2B1 system formed the MI complex with all substrates tested, and the enantioselectivity observed with the microsomal system was reproduced. In the P450 2C11 system the nitroso compounds were completely inactive, whereas the enantiomers of N-hydroxyamphetamine still produced the complex at a high rate. Changes in temperature were shown to affect (R)-2-nitroso-1-phenylpropane more than its enantiomer. Both enantiomers showed biphasic Arrhenius plots for MI complex formation in microsomes (breaks around 22°C), but the activation energies of the (R)-isomer were about five times higher than those of the (S)-isomer. A theory is presented which suggests different modes of interaction with the active site of P-450 to account for the different behaviour of the various substrates. © 1992 Wiley-Liss, Inc.

The absorption of a pharmacological dose of vitamin D3 from two different lipid vehicles, peanut oil, containing long chain fatty acids, and a medium chain triglyceride was compared. Serial measurements of the serum concentration of vitamin D3 after dosage were made. The serum levels of 25-hydroxyvitamin D3, the major circulating vitamin D3 metabolite, were also determined. The analytical methods used were based on HPLC. In the fasting state, the serum levels of vitamin D3 were significantly higher after administration in peanut oil than after administration in the medium chain triglyceride. When the vitamin D3 dose was ingested together with food no difference between the two formulations was observed. Only small inter-formulation differences in serum 25-hydroxyvitamin D3 levels were detected. The results indicate that the presence of long chain fatty acids facilitates the absorption of vitamin D3.

Menadione and diquat cause toxicity in isolated hepatocytes. The toxicities of both menadione and diquat are primarily due to redox cycling and consequent oxidative stress. Menadione toxicity, however, has another component as the compound also possesses alkylating and oxidating properties allowing it to interact directly with cellular nucleophiles. Sulfite afforded considerable protection of isolated rat hepatocytes against the toxicity of menadione. This protective effect of sulfite may have several components. Sulfite effectively competed with glutathione (GSH) for conjugation with menadione, sparing intracellular GSH which may continue to detoxify reactive oxygen species formed through menadione redox cycling. The menadione sulfite conjugate undergoes much slower redox cycling than both menadione and the menadione glutathione conjugate. Sulfite also showed some degree of protection of hepatocytes from the toxicity of diquat. Diquat is a "pure" redox cycling agent and the protective effect of sulfite may involve the liberation of GSH from GSSG by sulfitolysis. This would again bolster intracellular GSH levels allowing further GSH-dependent detoxification of reactive oxygen species through cellular GSH peroxidases. In conclusion, our data illustrate the potential of inorganic sulfite to support the intracellular detoxification function of GSH, both against reactive electrophilic metabolites and against agents undergoing redox cycling.

On gas chromatographic analysis, N-(5-pyrrolidinopent-3-ynyl)succinimide N'-oxide gave rise to three main decomposition products, which were assigned the structures N-(3-oxopent-4-enyl)succinimide, N-(penta-3, 4-dienyl)succinimide and N-3(3-pyrrolidino-3-oxopropyl)succinimide. These three products were identified by electron impact mass spectrometry, using deuterium substituted N-oxides, and mechanisms for the formation of the former two are proposed. By gas chromatographic mass spectrometric analysis, extracts from metabolic incubation of N-(5-pyrrolidinopent-3-ynyl)succinimide were shown to contain the N-oxide, as previously indicated by indirect methods.

The rate of decomposition of some trans-α-alkyl-substituted 2-nitroso-1-phenylethane dimers, including one deuterium-substituted analogue, has been measured spectrophotometrically in the temperature range 15–60 °C in ethanol, ethanol–water, cyclohexane, carbon tetrachloride, and chloroform. From studies in ethanol the rate constant of monomer formation, k1, the Arrhenius parameters, and the heat and entropy of activation were evaluated. The observed rate constant, kobs, evaluated from a first-order plot of the decomposition of the secondary C-nitroso dimers decreased with increasing initial concentrations and with increasing size of the α-alkyl substitutent. C-Nitroso dimers with one α-hydrogen decomposed up to 1 200 times faster in ethanol than in non-polar solvents. The decomposition rate of one dimer without α-hydrogens was comparatively independent of the solvent used. However, the addition of water to the ethanol solutions had a stabilizing effect on both types of dimers. The isotope effect, kH/kD, was shown to be 2–5 on k1, and 3–5 on kobs for the dimer of 2-nitroso-1-phenylpropane.