Global QCD Analysis of Pion Parton Distributions with Threshold Resummation.

We perform the first global QCD analysis of pion valence, sea quark, and gluon distributions within a Bayesian Monte Carlo framework with threshold resummation on Drell-Yan cross sections at next-to-leading log accuracy. Exploring various treatments of resummation, we find that the large-x asymptotics of the valence quark distribution ∼(1-x)^{ß_{v}} can differ significantly, with ß_{v} ranging from ≈1 to >2.5 at the input scale. Regardless of the specific implementation, however, the resummation induced redistribution of the momentum between valence quarks and gluons boosts the total momentum carried by gluons to ≈40%, increasing the gluon contribution to the pion mass to ≈40 MeV.

First Monte Carlo Global QCD Analysis of Pion Parton Distributions.

We perform the first global QCD analysis of parton distribution functions (PDFs) in the pion, combining πA Drell-Yan data with leading neutron electroproduction from HERA within a Monte Carlo approach based on nested sampling. Inclusion of the HERA data allows the pion PDFs to be determined down to much lower values of x, with relatively weak model dependence from uncertainties in the chiral splitting function. The combined analysis reveals that gluons carry a significantly higher pion momentum fraction, ∼30%, than that inferred from Drell-Yan data alone, with sea quarks carrying a somewhat smaller fraction, ∼15%, at the input scale. Within the same effective theory framework, the chiral splitting function and pion PDFs can be used to describe the d[over ¯]-u[over ¯] asymmetry in the proton.

Postoperative analgesia in dental day case surgery. A comparison between Feldene "Melt' (piroxicam) and diclofenac suppositories.

A randomised, double-blind placebo-controlled trial was conducted to compare the analgesic efficacy of piroxicam as Feldene "Melt' with diclofenac suppositories following day case wisdom tooth extraction. Piroxicam was found to be equivalent to diclofenac in speed of onset and efficacy when given 1 h prior to surgery with no significant adverse effects. It is therefore possible to confer the benefits of postoperative analgesia from a non-steroidal anti-inflammatory drug whilst avoiding the inconvenience of the rectal route of administration.

Undiagnosed raised intracranial pressure complicating labour.

A 30-year-old woman was admitted to the labour ward at term complaining of symptoms suggestive of raised intracranial pressure which were overlooked. Epidural analgesia was administered following induction of labour and was associated with a clear exacerbation of symptoms. After delivery a CT scan revealed a large cerebello-pontine angle tumour with obstructive hydrocephalus. This case report and literature review demonstrate the importance of a reasonable level of clinical suspicion and a careful neurological examination in patients with such symptomatology to allow sensible and safe guidance through labour.

Effect of vitamin E deficiency and supercritical fluid aerosolized vitamin E supplementation on interleukin-1-induced oxidative lung injury in rats.

We hypothesized that alterations in lung vitamin E levels would impact the development of acute oxidative lung injury. We found that dietary induced deficiency of vitamin E diminished lung tissue levels of vitamin E and increased lung leak following intratracheal administration of interleukin-1 (IL-1) to rats. Conversely, rats administered vitamin E directly to the lungs as an inhaled aerosol (0.3-3 microns particles) formed by supercritical fluid aerosolization (SFA) had increased lung tissue vitamin E levels and decreased IL-1 induced lung leak compared to control rats. Lung myeloperoxidase (MPO) activities, reflecting neutrophil concentrations, were increased in rats given IL-1 intratracheally compared to rats given saline intratracheally but were not different for control or vitamin E depleted rats. Lung MPO activities in rats given IL-1 intratracheally were slightly higher in SFA vitamin E treated rats than in control rats. Our results suggest that vitamin E levels affect susceptibility to IL-1 induced, neutrophil-dependent lung injury. We speculate that supercritical fluid aerosol (SFA) delivery of vitamin E can rapidly increase lung vitamin E levels and decrease acute oxidative lung injury.

Factitious food allergy and failure to thrive.

OBJECTIVE: To examine the relationship between parental beliefs about factitious food allergies and failure to thrive in their children. RESEARCH DESIGN: Retrospective case review. SETTING: Tertiary care referral center in Denver, Colo. SELECTION PROCEDURES: A consecutive sample of more than 700 patients referred for evaluation of food allergies was screened for age; negative results to double-blind, placebo-controlled food challenges; and failure to thrive. MEASUREMENTS/RESULTS: After identifying two probands, we identified nine additional children with failure to thrive in the context of parents' beliefs in allergic reactions to multiple foods. The results of puncture skin tests conducted for foods suspected of causing allergic reactions were negative for seven (64%) of the 11 children. There were no allergic reactions to open challenges (ie, children, staff, and parents knew which food was being tested). Only two patients reacted during double-blind, placebo-controlled food challenges. One reacted to milk (one of 14 suspected foods) and the other reacted to eggs and milk (two of 15 suspected foods). CONCLUSIONS: Parental beliefs about food allergies can lead to dietary restrictions severe enough to cause failure to thrive in their children. Because of the wide-spread belief by parents that children are allergic to food, pediatricians are frequently faced with the question of whether to subject children to food restrictions. Their collaboration with unsubstantiated parental beliefs can have long-term, deleterious consequences.