High-'n'-dry? A comparison of cannabis and alcohol use in drivers presenting to hospital after a vehicular collision

DESIGN

This was a prospective observational study.

BACKGROUND AND AIMS

The characteristics of cannabis-involved motor vehicle collisions are poorly understood. This study of injured drivers identifies demographic and collision characteristics associated with high tetrahydrocannabinol (THC) concentrations.

SETTING

The study was conducted in 15 Canadian trauma centres between January 2018 and December 2021.

CASES

The cases (n = 6956) comprised injured drivers who required blood testing as part of routine trauma care.

MEASUREMENTS

We quantified whole blood THC and blood alcohol concentration (BAC) and recorded driver sex, age and postal code, time of crash, crash type and injury severity. We defined three driver groups: high THC (THC ≥ 5 ng/ml and BAC = 0), high alcohol (BAC ≥ 0.08% and THC = 0) and THC/BAC-negative (THC = 0 = BAC). We used logistic regression techniques to identify factors associated with group membership.

FINDINGS

Most injured drivers (70.2%) were THC/BAC-negative; 1274 (18.3%) had THC > 0, including 186 (2.7%) in the high THC group; 1161 (16.7%) had BAC > 0, including 606 (8.7%) in the high BAC group. Males and drivers aged less than 45 years had higher adjusted odds of being in the high THC group (versus the THC/BAC-negative group). Importantly, 4.6% of drivers aged less than 19 years had THC ≥ 5 ng/ml, and drivers aged less than 19 years had higher unadjusted odds of being in the high THC group than drivers aged 45-54 years. Males, drivers aged 19-44 years, rural drivers, seriously injured drivers and drivers injured in single-vehicle, night-time or weekend collisions had higher adjusted odds ratios (aORs) for being in the high alcohol group (versus THC/BAC-negative). Drivers aged less than 35 or more than 65 years and drivers involved in multi-vehicle, daytime or weekday collisions had higher adjusted odds for being in the high THC group (versus the high BAC group).

CONCLUSIONS

In Canada, risk factors for cannabis-related motor vehicle collisions appear to differ from those for alcohol-related motor vehicle collisions. The collision factors associated with alcohol (single-vehicle, night-time, weekend, rural, serious injury) are not associated with cannabis-related collisions. Demographic factors (young drivers, male drivers) are associated with both alcohol and cannabis-related collisions, but are more strongly associated with cannabis-related collisions.

Assessing Human Health PM2.5 and Ozone Impacts from U.S. Oil and Natural Gas Sector Emissions in 2025

Incomplete information regarding emissions from oil and natural gas production has historically made it challenging to characterize the air quality or air pollution-related health impacts for this sector in the United States. Using an emissions inventory for the oil and natural gas sector that reflects information regarding the level and distribution of PM_2.5 and ozone precursor emissions, we simulate annual mean PM_2.5 and summer season average daily 8 h maximum ozone concentrations with the Comprehensive Air-Quality Model with extensions (CAMx). We quantify the incidence and economic value of PM_2.5 and ozone health related effects using the environmental Benefits Mapping and Analysis Program (BenMAP). We find that ambient concentrations of PM_2.5 and ozone, and associated health impacts, are highest in a handful of states including Colorado, Pennsylvania, Texas and West Virginia. On a per-ton basis, the benefits of reducing PM_2.5 precursor emissions from this sector vary by pollutant species, and range from between $6,300 and $320,000, while the value of reducing ozone precursors ranges from $500 to $8,200 in the year 2025 (2015$).

Predictors of Unintentional Injuries in Paediatric Immigrants in Ontario

BACKGROUND: Unintentional injury is a frequent reason for emergency department visits and is the leading cause of death for Canadian children. Injury is associated with a number of socio-demographic variables but it is not known whether being an immigrant changes this risk.

OBJECTIVES: To examine the association between family immigrant status and unintentional injury; and to test this relationship within immigrants by refugee status.

DESIGN/METHODS: Retrospective population-based cross-sectional study of children ages 0 to 14 years residing in Ontario, Canada from 2008 to 2012, using linked health administrative databases and Citizenship and Immigration Canada’s Permanent Resident Database. The main exposure was immigration status (immigrant or child of an immigrant vs. Canadian born). Secondary exposure was refugee status. Main outcome measure was unintentional injury events (emergency department visits, hospitaliza-tions, deaths), annualized. Data were analyzed using Poisson regression models to estimate risk ratios (RR) for unintentional injuries.

RESULTS: There were 11 464 317 injuries per year. Non-immigrant children sustained 12051 injuries/100 000 and immigrants had 6837 injuries/100 000, annually. In adjusted models, immigrants had a significantly lower risk of injury compared with non-immigrant children (RR 0.60; 95% confidence interval [CI] 0.57, 0.63). Overall, the most materially deprived neighbourhood quintile was associated with a higher rate of injury (RR 1.13; 95% CI 1.07, 1.02, quintile 5 vs. 1) whereas within immigrants, material deprivation was associated with a lower rate of injury (RR 0.96; 95% CI 0.94, 0.98, quintile 5 vs. 1). Other predictors of injury included age (0 to 4 years: RR 0.84; 95% CI 0.81, 0.88; 5 to 9 years: RR 0.70; 95% CI 0.67, 0.73), male sex (RR 1.30; 95% CI 1.26, 1.35), and rural residence (RR 1.50; 95% CI 1.43, 1.57). Injury rates were lower in immigrants across all types of unintentional injuries. Within immigrants, refugees had a higher risk of injury compared with non-refugees (RR 1.12; 95% CI 1.10, 1.14). This risk was particularly high for motor vehicle accidents (RR = 1.58; 95% CI 1.46, 1.71) and scald burns (RR 1.23; 95% CI 1.11, 1.35).

CONCLUSION: Risk of unintentional injury is lower among immigrants compared with Canadian-born children. These findings support a healthy immigrant effect. Socioeconomic status has a different effect on injury risk in immigrant and non-immigrant populations, suggesting alternative causal pathways for injuries in immigrants. Risk of unintentional injury is higher in refugees versus non-refugee immigrants, highlighting a population in need of targeted injury prevention strategies.

Canadian parents' attitudes and beliefs about bicycle helmet legislation in provinces with and without legislation

INTRODUCTION

The objective of this study was to survey Canadian parents on their attitudes and beliefs about bicycle helmet legislation and to compare responses from parents living in provinces with and without legislation.

METHODS

A national survey of 1002 parents of children aged under 18 years was conducted. Chi-square tests were used to compare responses from the surveyed parents in the different jurisdictions.

RESULTS

Responses from parents living in provinces with legislation (n = 640) and without legislation (n = 362) were as follows: concern for injury (63% vs. 68%, nonsignificant [NS]); believe helmets are effective (98% vs. 98%, NS); child always wears a helmet (74% vs. 69%, NS); support legislation for children (95% vs. 83%, p < .001); support legislation for all ages (85% vs. 75%, p < .001); support police enforcement (83% vs. 76%, p = .003); believe legislation decreases the amount of time their child bicycles (5% vs. 8%, NS).

CONCLUSION

Parents are highly supportive of bicycle helmet legislation in Canada. They believe that bicycle helmets are effective and that legislation does not decrease the amount of time a child spends bicycling. There was also a high level of support for legislation across all ages, and for police enforcement.

Reaction time-monitored patient-maintained propofol sedation: a pilot study in oral surgery patients

Previous volunteer studies of an effect-site controlled patient-maintained sedation system using propofol have demonstrated a risk of oversedation. We have incorporated a reaction time monitor into the handset to add an individualised patient-feedback mechanism. This pilot study assessed if the reaction time-feedback modification would prove safe and effective in 20 healthy patients receiving sedation while undergoing oral surgery. All patients successfully sedated themselves without reaching any unsafe endpoints. All 20 maintained verbal contact throughout. The mean (SD) lowest peripheral blood oxygen saturation was 98.0 (2.1)% breathing room air. No patient required supplementary oxygen. The mean (SD) maximum effect-site propofol concentration reached was 1.6 (0.5) μg.ml(-1). The present system was found to be safe and effective, allowing oral surgery treatment under conscious sedation, but preventing oversedation.

Measurement of dijet angular distributions and search for quark compositeness in pp collisions at √s = 7 TeV

Dijet angular distributions are measured over a wide range of dijet invariant masses in pp collisions at √s = 7 TeV, at the CERN LHC. The event sample, recorded with the CMS detector, corresponds to an integrated luminosity of 36 pb⁻¹. The data are found to be in good agreement with the predictions of perturbative QCD, and yield no evidence of quark compositeness. With a modified frequentist approach, a lower limit on the contact interaction scale for left-handed quarks of Λ⁺ = 5.6 TeV (Λ⁻ = 6.7 TeV) for destructive (constructive) interference is obtained at the 95% confidence level.

Search for pair production of second-generation scalar leptoquarks in pp collisions at √s = 7 TeV

A search for pair production of second-generation scalar leptoquarks in the final state with two muons and two jets is performed using proton-proton collision data at √s = 7 TeV collected by the CMS detector at the LHC. The data sample used corresponds to an integrated luminosity of 34 pb⁻¹. The number of observed events is in good agreement with the predictions from the standard model processes. An upper limit is set on the second-generation leptoquark cross section times β² as a function of the leptoquark mass, and leptoquarks with masses below 394 GeV are excluded at a 95% confidence level for β = 1, where β is the leptoquark branching fraction into a muon and a quark. These limits are the most stringent to date.

Search for pair production of first-generation scalar leptoquarks in pp collisions at √s = 7 TeV

A search for pair production of first-generation scalar leptoquarks is performed in the final state containing two electrons and two jets using proton-proton collision data at √s = 7 TeV. The data sample used corresponds to an integrated luminosity of 33 pb⁻¹ collected with the CMS detector at the CERN LHC. The number of observed events is in good agreement with the predictions for the standard model background processes, and an upper limit is set on the leptoquark pair production cross section times β² as a function of the leptoquark mass, where β is the branching fraction of the leptoquark decay to an electron and a quark. A 95% confidence level lower limit is set on the mass of a first-generation scalar leptoquark at 384 GeV for β = 1, which is the most stringent direct limit to date.

Dijet azimuthal decorrelations in pp collisions at √s=7 TeV

Measurements of dijet azimuthal decorrelations in pp collisions at √s=7 TeV using the CMS detector at the CERN LHC are presented. The analysis is based on an inclusive dijet event sample corresponding to an integrated luminosity of 2.9 pb⁻¹. The results are compared to predictions from perturbative QCD calculations and various Monte Carlo event generators. The dijet azimuthal distributions are found to be sensitive to initial-state gluon radiation.

Measurement of the B(+) production cross section in pp collisions at sqrt[s]=7 TeV

Measurements of the total and differential cross sections dσ/dp(T)(B) and dσ/dy(B) for B(+) mesons produced in pp collisions at sqrt[s]=7  TeV are presented. The data correspond to an integrated luminosity of 5.8  pb(-1) collected by the CMS experiment operating at the LHC. The exclusive decay B(+)→J/ψK(+), with J/ψ→μ(+)μ(-), is used to detect B(+) mesons and to measure the production cross section as a function of p(T)(B) and y(B). The total cross section for p(T)(B)>5  GeV and |y(B)|<2.4 is measured to be 28.1±2.4±2.0±3.1  μb, where the first uncertainty is statistical, the second is systematic, and the last is from the luminosity measurement.

Measurement of the isolated prompt photon production cross section in pp collisions at √s=7 TeV

The differential cross section for the inclusive production of isolated prompt photons has been measured as a function of the photon transverse energy E(T)(γ) in pp collisions at √s=7  TeV using data recorded by the CMS detector at the LHC. The data sample corresponds to an integrated luminosity of 2.9  pb(-1). Photons are required to have a pseudorapidity |η(γ)|<1.45 and E(T)(γ)>21  GeV, covering the kinematic region 0.006<x(T)<0.086. The measured cross section is found to be in agreement with next-to-leading-order perturbative QCD calculations.

Search for stopped Gluinos in pp collisions at square root s=7 TeV

The results of the first search for long-lived gluinos produced in 7 TeV pp collisions at the CERN Large Hadron Collider are presented. The search looks for evidence of long-lived particles that stop in the CMS detector and decay in the quiescent periods between beam crossings. In a dataset with a peak instantaneous luminosity of 1×10(32) cm-2 s-1, an integrated luminosity of 10 pb-1, and a search interval corresponding to 62 hours of LHC operation, no significant excess above background was observed. Limits at the 95% confidence level on gluino pair production over 13 orders of magnitude of gluino lifetime are set. For a mass difference mg - mχ1(0) >100 GeV/c2, and assuming BR(g→gχ1(0))=100%, mg < 370 GeV/c2 are excluded for lifetimes from 10 μs to 1000 s.

Search for quark compositeness with the dijet centrality ratio in pp collisions at √s=7 TeV

A search for quark compositeness in the form of quark contact interactions, based on hadronic jet pairs (dijets) produced in proton-proton collisions at √s=7 TeV, is described. The data sample of the study corresponds to an integrated luminosity of 2.9 pb(-1) collected with the CMS detector at the LHC. The dijet centrality ratio, which quantifies the angular distribution of the dijets, is measured as a function of the invariant mass of the dijet system and is found to agree with the predictions of the standard model. A statistical analysis of the data provides a lower limit on the energy scale of quark contact interactions. The sensitivity of the analysis is such that the expected limit is 2.9 TeV; because the observed value of the centrality ratio at high invariant mass is below the expectation, the observed limit is 4.0 TeV at the 95% confidence level.

Search for dijet resonances in 7 TeV pp collisions at CMS

A search for narrow resonances in the dijet mass spectrum is performed using data corresponding to an integrated luminosity of 2.9 pb⁻¹ collected by the CMS experiment at the Large Hadron Collider. Upper limits at the 95% confidence level are presented on the product of the resonance cross section, branching fraction into dijets, and acceptance, separately for decays into quark-quark, quark-gluon, or gluon-gluon pairs. The data exclude new particles predicted in the following models at the 95% confidence level: string resonances, with mass less than 2.50 TeV, excited quarks, with mass less than 1.58 TeV, and axigluons, colorons, and E6 diquarks, in specific mass intervals. This extends previously published limits on these models.

First measurement of Bose-Einstein correlations in proton-proton collisions at √s=0.9 and 2.36 TeV at the LHC

Bose-Einstein correlations have been measured using samples of proton-proton collisions at 0.9 and 2.36 TeV center-of-mass energies, recorded by the CMS experiment at the CERN Large Hadron Collider. The signal is observed in the form of an enhancement of pairs of same-sign charged particles with small relative four-momentum. The size of the correlated particle emission region is seen to increase significantly with the particle multiplicity of the event.

Transverse-momentum and pseudorapidity distributions of charged hadrons in pp collisions at square root of s = 7 TeV

Charged-hadron transverse-momentum and pseudorapidity distributions in proton-proton collisions at square root of s = 7  TeV are measured with the inner tracking system of the CMS detector at the LHC. The charged-hadron yield is obtained by counting the number of reconstructed hits, hit pairs, and fully reconstructed charged-particle tracks. The combination of the three methods gives a charged-particle multiplicity per unit of pseudorapidity dN(ch)/dη|(|η|<0.5) = 5.78 ± 0.01(stat) ± 0.23(syst) for non-single-diffractive events, higher than predicted by commonly used models. The relative increase in charged-particle multiplicity from square root of s = 0.9 to 7 TeV is [66.1 ± 1.0(stat) ± 4.2(syst)]%. The mean transverse momentum is measured to be 0.545 ± 0.005(stat) ± 0.015(syst)  GeV/c. The results are compared with similar measurements at lower energies.

Hypersensitivity and oral tolerance in the absence of a secretory immune system

BACKGROUND

Mucosal immunity protects the epithelial barrier by immune exclusion of foreign antigens and by anti-inflammatory tolerance mechanisms, but there is a continuing debate about the role of secretory immunoglobulins (SIgs), particularly SIgA, in the protection against allergy and other inflammatory diseases. Lack of secretory antibodies may cause immune dysfunction and affect mucosally induced (oral) tolerance against food antigens.

METHODS

We used polymeric Ig receptor (pIgR) knockout (KO) mice, which cannot export SIgA or SIgM, to study oral tolerance induction by ovalbumin (OVA) feeding and for parenteral antigen sensitization in the same animal.

RESULTS

Remarkable systemic hyperreactivity was observed in pIgR KO mice, as 50% died after intradermal OVA challenge, which was not seen in similarly sensitized and challenged wild-type (WT) mice. Oral tolerance induced by OVA completely protected the sensitized pIgR KO mice against anaphylaxis and suppressed antibody levels (particularly IgG1) as well as delayed-type hypersensitivity (DTH) to OVA. Delayed-type hypersensitivity to a bystander antigen, human serum albumin, was also suppressed and T-cell proliferation against OVA in vitro was reduced in tolerized compared with non-tolerized pIgR KO mice. This effect was largely mediated by CD25+ T cells. Adoptive transfer of splenic putative regulatory T cells (CD4+ CD25+) obtained from OVA-fed pIgR KO mice to naïve WT mice mediated suppression of DTH against OVA after sensitization of the recipients.

CONCLUSION

Compensatory regulatory T-cell function becomes critical in pIgR-deficient mice to avoid the potentially catastrophic effects of systemic immune hyperreactivity, presumably resulting from defective secretory antibody-mediated immune exclusion of microbial components.

Bicycle helmet legislation for the uptake of helmet use and prevention of head injuries

BACKGROUND

Evidence exists to suggest that bicycle helmets may reduce the risk of head injuries to cyclists, however helmets are not uniformly worn by all bicycle users. Legislation has been enacted in some countries to mandate helmet use by cyclists, however the issue remains controversial with opponents arguing that this may inhibit people from bicycle riding and thus from gaining the associated health benefits, or that other countermeasures may have been responsible for decline in head injuries.

OBJECTIVES

To assess the effects of bicycle helmet legislation on bicycle-related head injuries and helmet use, and the occurrence of unintended adverse consequences.

SEARCH STRATEGY

We searched CENTRAL, the Cochrane Injuries Group's specialised register, MEDLINE, EMBASE, TRANSPORT and other specialist electronic databases, up to February 2006. In addition we searched government websites, handsearched selected journals and examined the reference lists of selected publications.

SELECTION CRITERIA

We included studies that reported changes in either the number of head injuries, helmet use or bicycle use post- versus pre-legislation. Only studies that included a concurrent control group and which reported on the effect of legislation implemented at either the country, state or province wide level were included.

DATA COLLECTION AND ANALYSIS

Two authors independently extracted data and assessed methodological quality. The data were not appropriate for meta-analysis, thus the results of the included studies have been reviewed narratively.

MAIN RESULTS

Five studies, all from North America, met the inclusion criteria. For each of the studies, bicycle helmet legislation had been enacted for children only. Adults were used as controls in four of the studies, whilst jurisdictions with no helmet legislation were used as controls in the fifth. Three of the studies reported on changes in head injury rates and three reported on changes in helmet use. There were no included studies reporting change in bicycle use or other adverse consequences of legislation. In two studies, statistically significant decreases in head injuries were reported following the implementation of helmet legislation compared with controls, whilst one reported a non-statistically significant decline. Bicycle helmet use increased statistically significantly post-legislation in all three of the studies reporting on helmet use.

AUTHORS' CONCLUSIONS

Bicycle helmet legislation appears to be effective in increasing helmet use and decreasing head injury rates in the populations for which it is implemented. However, there are very few high quality evaluative studies that measure these outcomes, and none that reported data on an possible declines in bicycle use.

Internet health information use and e-mail access by parents attending a paediatric emergency department

OBJECTIVES

To document internet access and health related usage patterns by families of children in a large paediatric emergency department (ED), and to discover if parents want the internet to become a tool for transferring medical test results.

METHODS

This was a pre-tested, 21 item, interview conducted with parents at the paediatric ED in Toronto over 3 months. Descriptive statistics and frequency distributions were calculated and variables associated with parents wishing to access results electronically were examined.

RESULTS

In total, 950 parents completed the interview (93%), of whom 87% reported routine internet access, 75% reported having an e-mail account, and 60% accessed their e-mail once or more a day. Over half (56%) reported searching the internet for health related information, with 8.5% of these searching immediately preceding their visit. Nearly three quarters (73%) indicated they would like to receive an e-mail containing the results of tests conducted in the ED; 66% of all respondents and 89% of those with e-mail indicated that they would like their child's primary care provider to receive information electronically.

CONCLUSION

The majority of families have internet access and most want to receive medical information electronically and to send it to the primary provider. The vast use of internet for health related information emphasises the need to guide parents regarding reliable resources online, possibly as part of their ED visit.

Genetic variation at the chromosome 16 chemokine gene cluster: development of a strategy for association studies in complex disease

The chemokine gene cluster [CCL22, CX3CL1, CCL17] (previously known as [SCYA22, SCYD1, SCYA17]) is a candidate locus for one of the susceptibility genes for inflammatory bowel disease that are located in the peri-centromeric region of chromosome 16. Screening for sequence variation at this locus led to the detection of 14 single nucleotide polymorphisms (SNPs). An efficient experimental and computational approach was developed to estimate allele frequencies and pairwise linkage disequilibrium relationships between SNPs at this locus, and to test them for association with inflammatory bowel disease. The 12 common SNPs were assigned to 5 distinct linkage disequilibrium groups. Genotyping of one SNP from each linkage disequilibrium group in a large cohort of families with inflammatory bowel disease did not provide convincing evidence of association with either Crohn's disease or ulcerative colitis. We describe an efficient experimental design from SNP screening to association testing. This strategy can be used to test candidate genes for involvement in susceptibility to complex disease.

Association of reduced selenium status in the aetiology of recurrent miscarriage

OBJECTIVE

To determine whether recurrent miscarriage is associated with reduced selenium status.

DESIGN

Case-control study.

SETTING

Department of Obstetrics and Gynaecology, Glasgow Royal Infirmary and Glasgow Royal Maternity Hospital.

POPULATION

Twenty nonpregnant women with a history of unexplained recurrent miscarriage, and 47 nonpregnant parous women with a history of at least one successful pregnancy and no more than one miscarriage.

METHODS

A 7 mL blood sample from each woman was collected into lithium heparin 'vacutainer' tubes. Samples were centrifuged at 3000 g for 15 minutes, and plasma was extracted and stored at -20 degrees C. Selenium concentrations were measured using a fluorescence spectrophotometer. The selenium concentrations in the two groups were compared and the differences examined using the Student's t test.

MAIN OUTCOME MEASURES

Plasma selenium concentration (microg/L).

RESULTS

The mean selenium concentration for women with a history of unexplained recurrent miscarriage was 67.7 microg/L (SD 16.4). The selenium level for the women with no history of recurrent miscarriage was 70.3 microg/L (SD 12.7). There was no difference in selenium concentrations between the two groups (P = 0.53).

CONCLUSIONS

In this study there is no association between unexplained recurrent miscarriage and reduced selenium status, implying that reduced selenium status is not a factor in the pathogenesis of recurrent miscarriage. We can find no rationale for a trial of selenium therapy in women with a history of recurrent miscarriage.

Children's exposure to traffic and pedestrian injuries

OBJECTIVES

The purpose of this study was to estimate children's exposure to traffic (number of streets crossed) and to determine the role of exposure in pedestrian injury.

METHODS

Questionnaires were distributed to a random sample of 4080 first- and fourth-grade children in 43 Montreal schools.

RESULTS

When analyzed by police district, injury and exposure rates were positively correlated (r2 = 0.53). Crossings were similar by sex but increased with age and were inversely related to socioeconomic status.

CONCLUSIONS

These results suggest that although children's exposure to traffic could be reduced by transporting them to school, a more reasonable prevention strategy involves environmental changes.

Intestinal permeability and inflammation in patients on NSAIDs

BACKGROUND

The frequency with which non-steroidal anti-inflammatory drugs (NSAIDs) increase small intestinal permeability and cause inflammation is uncertain.

AIMS

To examine small intestinal permeability and inflammation in a large number of patients on long term NSAIDs.

METHODS

Sixty eight patients receiving six different NSAIDs for over six months underwent combined absorption-permeability tests at three different test dose osmolarities (iso-, hypo-, and hyperosmolar). Two hundred and eighty six patients on 12 different NSAIDs underwent indium-111 white cell faecal excretion studies to assess the prevalence and severity of intestinal inflammation.

RESULTS

The iso- and hyperosmolar tests showed significant malabsorption of 3-0-methyl-D-glucose, D-xylose, and L-rhamnose. Intestinal permeability changes were significantly more pronounced and frequent with the hypo- and hyperosmolar as opposed to the iso-osmolar test. Sequential studies showed that four and nine patients (of 13) developed inflammation after three and six months treatment with NSAIDs, respectively. There was no significant difference (p>0.1) in the prevalence (54-72%) or severity of intestinal inflammation in the 286 patients taking the various NSAIDs apart from those on aspirin and nabumetone, these having no evidence of intestinal inflammation. There was no significant correlation between the inflammatory changes and age, sex, dose of NSAID, length of disease, or NSAID ingestion.

CONCLUSIONS

Intestinal permeability test dose composition is an important factor when assessing the effects of NSAIDs on intestinal integrity. All the conventional NSAIDs studied were equally associated with small intestinal inflammation apart from aspirin and nabumetone which seem to spare the small bowel.

Effect of vitamin E and selenium supplementation of cockerel diets on glutathione peroxidase activity and lipid peroxidation susceptibility in sperm, testes, and liver

The phospholipids of avian spermatozoa are characterized by high proportions of arachidonic (20:4n-6) and docosatetraenoic (22:4n-6) fatty acids and are therefore sensitive to lipid peroxidation. Alpha-tocopherol and glutathione peroxidase [GSH-Px] are believed to be the primary components of the antioxidant system of the spermatozoa. The present study evaluates the effect of vitamin E and vitamin E plus Se supplementation of the cockerel diet on GSH-Px activity, vitamin E accumulation, and lipid peroxidation in the spermatozoa, testes, and liver. At the beginning of the experiment 75 Rhode Island Red cockerels were divided into five groups, kept in individual cages, and fed a wheat-barley-based ration balanced in all nutrients. Supplements fed to the different groups were as follows: vitamin E, 0, 20, 200, 20, and 200 mg/kg to groups 1-5, respectively, with groups 4 and 5 also receiving 0. 3 mg Se/kg. The vitamin E supplementation produced increased levels of alpha-tocopherol in semen, testes, and liver. The inclusion of the Se into the cock diet had a significant (P < 0.01) stimulating effect on GSH-Px activity in seminal plasma, spermatozoa, testes, and liver. The increased vitamin E concentration in the spermatozoa was associated with a reduction in their susceptibility to lipid peroxidation. Similarly, the increased GSH-Px activity provided enhanced protection against lipid peroxidation.

Mitochondrial damage: a possible mechanism of the "topical" phase of NSAID induced injury to the rat intestine

BACKGROUND

The "topical" effect of non-steroidal anti-inflammatory drugs (NSAIDs) seems to be an important cause of NSAID induced gastrointestinal damage.

AIM

To examine the possible mechanism of the "topical" phase of damage in the small intestine.

METHODS

Electron microscopy and subcellular organelle marker enzyme studies were done in rat small intestine after oral administration of indomethacin (doses varied between 5 and 30 mg/kg). The effect of conventional and non-acidic NSAIDs on rat liver mitochondrial respiration was measured in vitro in a Clarke-type oxygen electrode.

RESULTS

The subcellular organelle marker enzymes showed mitochondrial and brush border involvement within an hour of indomethacin administration. Electron microscopy showed dose dependent mitochondrial changes following indomethacin administration consistent with uncoupling of oxidative phosphorylation (or inhibition of electron transport) which were indistinguishable from those seen with the uncoupler dinitrophenol. Parenteral indomethacin caused similar changes, but not in rats with ligated bile ducts. A range of NSAIDs, but not paracetamol or non-acidic NSAIDs which have a favourable gastrointestinal tolerability profile, uncoupled oxidative phosphorylation in vitro at micromolar concentrations and inhibited respiration at higher concentrations. In vivo studies with nabumetone and aspirin further suggested that uncoupling or inhibition of electron transport underlies the "topical" phase of NSAID induced damage.

CONCLUSION

Collectively, these studies suggest that NSAID induced changes in mitochondrial energy production may be an important component of the "topical" phase of damage induction.