Effect of Tooth Bleach on Dentin Fatigue Resistance in Situ

BACKGROUND

Negative effects of bleaching on dentin have previously been reported in vitro.

OBJECTIVE

The purpose of this study was to determine the effect of carbamide peroxide bleaching on dentin fatigue resistance using a clinically relevant in situ model.

METHODS AND MATERIALS

Following research ethics board approval, 60 human teeth requiring extraction were collected. Sterilized human dentin specimens were cut (1.2x1.2x10 mm) and secured into customized bleaching trays to be used by study participants. Participants were randomly assigned to either bleach (10% carbamide peroxide, n=23) or control (gel without bleach, n=26) treatment groups. Treatment was applied to the bleaching trays and worn overnight by participants for 14 days. After treatment completion, dentin specimens were removed from the bleaching trays and subjected to fatigue testing (10 N, 3 mm/s, 2x105 cycles) while submerged in artificial saliva. Kaplan-Meier survival analysis was conducted to compare the number of cycles to failure during fatigue testing in both groups. A log rank test was run to determine if there were differences in the survival distribution between the two groups (α<0.05).

RESULTS

The median number of cycles to failure was 352 ± 202 and 760 ± 644 for the bleach and control groups, respectively. The survival distributions for the two groups were significantly different (p=0.020). Dentin fatigue resistance was significantly lower in the bleach group compared to the control.

CONCLUSIONS

Direct bleaching of human dentin using an at-home tray bleaching protocol in situ reduced dentin fatigue resistance. This has implications for tooth fracture risk and longevity.

Mortality rates and proximal causes of death in patients with Lewy body dementia versus Alzheimer's disease: A longitudinal study using secondary care mental health records

BACKGROUND

Previous studies have shown reduced survival in Lewy body dementia (LBD) compared to Alzheimer's disease (AD), but the reasons for this are not known. We identified cause of death categories accounting for the reduced survival in LBD.

METHODS

We linked cohorts of patients with dementia with Lewy bodies (DLB), Parkinson's disease dementia (PDD) and AD, with proximal cause of death data. We examined mortality by dementia group and hazard ratios for each death category by dementia group in males and females separately. In a specific focus on the dementia group with the highest mortality rate versus reference, we examined cumulative incidence to identify the main causes of death accounting for the excess deaths.

RESULTS

Hazard ratios for death were higher in PDD and DLB compared to AD, for both males and females. PDD males had the highest hazard ratio for death across the dementia comparison groups (HR 2.7, 95% CI 2.2-3.3). Compared with AD, hazard ratios for "nervous system" causes of death were significantly elevated in all LBD groups. Additional significant cause-of-death categories included aspiration pneumonia, genitourinary causes, other respiratory causes, circulatory and a "symptoms and signs" category in PDD males; other respiratory causes in DLB males; mental disorders in PDD females; and aspiration pneumonia, genitourinary and other respiratory causes in DLB females.

CONCLUSION

Further research and cohort development is required to investigate differences by age group, to extend cohort follow-up to the whole population and to investigate the risk-balance of interventions which may differ by dementia group.

Stability of hippocampal subfield volumes after trauma and relationship to development of PTSD symptoms

BACKGROUND

The hippocampus plays a central role in post-traumatic stress disorder (PTSD) pathogenesis, and the majority of neuroimaging research on PTSD has studied the hippocampus in its entirety. Although extensive literature demonstrates changes in hippocampal volume are associated with PTSD, fewer studies have probed the relationship between symptoms and the hippocampus' functionally and structurally distinct subfields. We utilized data from a longitudinal study examining post-trauma outcomes to determine whether hippocampal subfield volumes change post-trauma and whether specific subfields are significantly associated with, or prospectively related to, PTSD symptom severity. As a secondary aim, we leveraged our unique study design sample to also investigate reliability of hippocampal subfield volumes using both cross-sectional and longitudinal pipelines available in FreeSurfer v6.0.

METHODS

Two-hundred and fifteen traumatically injured individuals were recruited from an urban Emergency Department. Two-weeks post-injury, participants underwent two consecutive days of neuroimaging (time 1: T1, and time 2: T2) with magnetic resonance imaging (MRI) and completed self-report assessments. Six-months later (time 3: T3), participants underwent an additional scan and were administered a structured interview assessing PTSD symptoms. First, we calculated reliability of hippocampal measurements at T1 and T2 (automatically segmented with FreeSurfer v6.0). We then examined the prospective (T1 subfields) and cross-sectional (T3 subfields) relationship between volumes and PTSD. Finally, we tested whether change in subfield volumes between T1 and T3 explained PTSD symptom variability.

RESULTS

After controlling for sex, age, and total brain volume, none of the subfield volumes (T1) were prospectively related to T3 PTSD symptoms nor were subfield volumes (T3) associated with current PTSD symptoms (T3). Tl - T2 reliability of all hippocampal subfields ranged from good to excellent (intraclass correlation coefficient (ICC) values > 0.83), with poorer reliability in the hippocampal fissure.

CONCLUSION

Our study was a novel examination of the prospective relationship between hippocampal subfield volumes in relation to PTSD in a large trauma-exposed urban sample. There was no significant relationship between subfield volumes and PTSD symptoms, however, we confirmed FreeSurfer v6.0 hippocampal subfield segmentation is reliable when applied to a traumatically-injured sample, using both cross-sectional and longitudinal analysis pipelines. Although hippocampal subfield volumes may be an important marker of individual variability in PTSD, findings are likely conditional on the timing of the measurements (e.g. acute or chronic post-trauma periods) and analysis strategy (e.g. cross-sectional or prospective).

The first survey of attitudes of medical students in Ireland towards termination of pregnancy

BACKGROUND

Since the UK Abortion Act (1967), women have travelled from Ireland to the UK for legal abortion. In 2011 >4000 women did so. Knowledge and attitudes of medical students towards abortion have been published, however, this is the first such report from Ireland.

OBJECTIVE

To investigate medical students' attitudes towards abortion in Ireland.

METHODS

All medical students at the University of Limerick, and physicians who graduated from the university within the previous 12 months, were invited via email to complete an anonymous online survey. The questionnaire comprised 17 questions. Quantitative and qualitative analyses were performed.

RESULTS

Response rate was 45% (n=169; 55% women; 88.2% <30 years of age; 66.7% Irish; 29.2% North American). Outcomes were: abortion should not be legally available (7.1%), abortion should be allowed in limited circumstances only (35.5%), abortion should be legally available upon request (55%). 72.8% of respondents were moderately/strongly prochoice (74% of women/71% of men/72% and 76% of Irish and North American respondents, respectively). Students aged >30 years were less likely to be prochoice (55%). While 95.2% believed that education on abortion should be offered within medical school curricula, 28.8% stated that they would decline to terminate pregnancies even if legally permitted. While 58.8% indicated that they might perform legal abortions once qualified, 25.7% would do so under limited circumstances only.

CONCLUSIONS

The majority of participants wanted education regarding abortion. Despite being predominantly prochoice, considerably fewer students, irrespective of nationality, indicated that they would perform abortions.

Delirium: a disturbance of circadian integrity?

Delirium is a serious neuropsychiatric syndrome of acute onset that occurs in approximately one in five general hospital patients and is associated with serious adverse outcomes that include loss of adaptive function, persistent cognitive problems and increased mortality. Recent studies indicate a three-domain model for delirium that includes generalised cognitive impairment, disturbed executive cognition, and disruption of behaviours that are under circadian control such as sleep-wake cycle and motor activity levels. As a consequence, attention has focused upon the possible role of the circadian timing system (CTS) in the pathophysiology of delirium. We explored this possibility by reviewing evidence that (1) many symptoms that occur in delirium are influenced by circadian rhythms, (2) many features of recognised circadian rhythm disorders are similar to characteristic features of delirium, (3) common risk factors for delirium are known to disrupt circadian systems, (4) physiological disturbances of circadian systems have been noted in delirious patients, and (5) positive effects in the treatment of delirium have been demonstrated for melatonin and related agents that influence the circadian timing system. A programme of future studies that can help to clarify the relevance of circadian integrity to delirium is described. Such work can provide a better understanding of the pathophysiology of delirium while also identifying opportunities for more targeted therapeutic efforts.

Is the delay in diagnosis of pulmonary tuberculosis related to exposure to fluoroquinolones or any antibiotic?

BACKGROUND

Delays in diagnosis of tuberculosis (TB) have been associated with previous use of antibiotics, and in particular fluoroquinolones (FQ), for suspected pulmonary infections.

METHODS

We conducted a population-based cohort study with 2232 patients who had active TB between 1997 and 2006 (records obtained from the British Columbia Linked Health Databases). Patients with a record of an initial health care contact preceding the diagnosis of TB were identified for inclusion. Health care delay was defined as the time between initial health care contact and the initiation of anti-tuberculosis medication, and was compared between patients prescribed antibiotics and those not exposed to any antibiotics.

RESULTS

A total of 1544 patients were included. After adjusting for covariates, average health care delay for patients exposed to antibiotics was found to be significantly greater, by a factor of 2.10 (95%CI 1.80-2.44), with a median delay of 41 days in the antibiotic group compared to 14 days in the non-antibiotic group. Sex, age, foreign-born status and socio-economic status were non-significant factors. Health care delay increased with the number of antibiotic courses received, but not with the type of antibiotic.

CONCLUSIONS

Previous treatment with any antibiotic, and not only a FQ, is associated with a delay in TB diagnosis.

Risk of upper gastrointestinal bleeding with oral bisphosphonates and non steroidal anti-inflammatory drugs: a case-control study

BACKGROUND

Gastrointestinal injuries including gastric ulcers have been reported with oral bisphosphonate therapy. However, the risk of the more serious upper gastrointestinal bleeding (UGB) especially in the community setting with these drugs remains unknown. Similarly, the risk of UGB among users of both bisphosphonates and non steroidal anti-inflammatory drugs (NSAIDs) in the community is also unknown.

AIM

To explore the risk of more serious UGB among users of bisphosphonates and the risk of UGB among users of both bisphosphonates and NSAIDs in the community.

METHODS

We conducted a case-control study within a cohort of Quebec residents who had received a revascularization procedure from 1995 to 2004. Cohort members were followed up from the date of their first procedure until the earliest of: (1) study outcome, (2) date of death or (3) end of health care coverage. Cases were defined as those with the first diagnosis of a UGB. For each case, 20 controls were selected and matched to the cases by index date, age and cohort entry. Adjusted odds ratios for current use of bisphosphonates, NSAIDs and co-therapy of both drugs were computed.

RESULTS

Within the initial cohort, 3253 incident cases of UGBs and corresponding 65 060 matched controls were identified. The adjusted odds ratio (OR) for UGB by current users of bisphosphonates was 1.01 (95% CI, 0.72-1.43). Current NSAID use was associated with an increased risk of UGB OR = 1.75; 95% CI, 1.53-1.99. The OR for use of bisphosphonates and NSAIDs was elevated OR = 2.00; 95% CI, 1.12-3.57. This risk was still elevated for users of bisphosphonates and COX-2 inhibitors [OR = 2.38 (95% CI, 1.26-4.50)].

CONCLUSION

We found no evidence of an increase in the risk of UGB among current users of bisphosphonates. The risk of combined NSAID and bisphosphonate therapy was increased, but this risk was not higher than the risk for NSAID users alone.

Cost-effectiveness of a new interferon-based blood assay, QuantiFERON-TB Gold, in screening tuberculosis contacts

BACKGROUND

Recent approval of interferon-gamma release assays that are more specific for Mycobacterium tuberculosis has given new options for the diagnosis of latent tuberculosis infection (LTBI).

OBJECTIVE

To assess the cost-effectiveness of Quanti-FERON-TB Gold (QFT-G) vs. the tuberculin skin test (TST) in diagnosing LTBI in contacts of active TB cases using a decision analytic Markov model.

METHODS

Three screening strategies--TST alone, QFT-G alone and sequential screening of TST then QFT-G--were evaluated. The model was further stratified according to ethnicity and bacille Calmette-Guérin (BCG) vaccination status. Data sources included published studies and empirical data. Results were reported in terms of the incremental net monetary benefit (INMB) of each strategy compared with the baseline strategy of TST-based screening in all contacts.

RESULTS

The most economically attractive strategy was to administer QFT-G in BCG-vaccinated contacts, and to reserve TST for all others (INMB CA$3.70/contact). The least cost-effective strategy was QFT-G for all contacts, which resulted in an INMB of CA$-11.50 per contact. Assuming a higher prevalence of recent infection, faster conversion of QFT-G, a higher rate of TB reactivation, reduction in utility or greater adherence to preventive treatment resulted in QFT-G becoming cost-effective in more subgroups.

CONCLUSIONS

Selected use of QFT-G appears to be cost-effective if used in a targeted fashion.

The combination of hydroxyurea and leucapheresis in the treatment of chronic myeloid leukaemia in pregnancy

Treatment of malignancy during pregnancy is difficult because of the potential teratogenicity of chemotherapeutic agents. Leucapheresis was employed in the initial management of a pregnant patient with chronic myeloid leukaemia. It was subsequently replaced with oral hydroxyurea during the second trimester. Successful delivery of a live male infant was achieved and the child has normal growth and development to date.

Budesonide/formoterol maintenance and reliever therapy: impact on airway inflammation in asthma

The aim of the present study was to compare the effectiveness, safety and health economics of budesonide/formoterol maintenance and a novel reliever therapy with conventional best practice in patients with persistent asthma in Canada. After 2 weeks of usual therapy, 1,538 patients were randomised for 6 months to open-label budesonide/formoterol maintenance and reliever therapy 160/4.5 microg twice daily and as needed, or to guideline-based conventional best practice. Severe asthma exacerbations, reliever medication use and total inhaled corticosteroid dose were analysed in all patients and airway inflammation was assessed in a sub-study of 115 patients. No differences were seen in time to first severe exacerbation and severe asthma exacerbation rate. There were numerically fewer emergency room visits or hospitalisations with budesonide/formoterol maintenance and reliever therapy (4.4 versus 7.5 events per 100 patients x yr(-1), 41% reduction); however, this did not reach statistical significance. Mean total inhaled corticosteroid dose, reliever use, asthma medication costs and total annual costs per patient were all significantly lower with budesonide/formoterol maintenance and reliever therapy. Mean sputum eosinophil cell counts remained in the range for controlled inflammation in both groups. In conclusion, budesonide/formoterol maintenance and reliever therapy achieved similar or improved clinical control compared with conventional best practice, with significantly lower total inhaled corticosteroid dose and lower cost, while maintaining similar control of eosinophilic inflammation.

The impact of obstructive sleep apnea and daytime sleepiness on work limitation

BACKGROUND

Many patients with obstructive sleep apnea (OSA) participate in the work force. However, the impact of OSA and sleepiness on work performance is unclear.

METHODS

To address this issue, we administered the Epworth Sleepiness Scale (ESS), the Work Limitations Questionnaire (WLQ), and an occupational survey to patients undergoing full-night polysomnography for the investigation of sleep-disordered breathing. Of 498 patients enrolled in the study, 428 (86.0%) completed the questionnaires. Their mean age+/-standard deviation (SD) was 49+/-12 years, mean body mass index (BMI) was 31+/-7 kg/m(2) mean apnea hypopnea index (AHI) was 21+/-22 events/h, and mean ESS score was 10+/-5. Subjects worked a mean of 39+/-18 h per week. The first 100 patients to complete the survey were followed up at two years.

RESULTS

In the group as a whole, there was no significant relationship between severity of OSA and the four dimensions of work limitation. However, in blue-collar workers, significant differences were detected between patients with mild OSA (AHI 5-15/h) and those with severe OSA (AHI>30/h) with respect to time management (limited 23.1% of the time vs. 43.8%, p=0.05) and mental/personnel interactions (17.9% vs. 33.0%, p=0.05). In contrast, there were strong associations between subjective sleepiness (as assessed by the ESS) and three of the four scales of work limitation. That is, patients with an ESS of 5 had much less work limitation compared to those with an ESS 18 in terms of time management (19.7% vs. 38.6 %, p<0.001), mental-interpersonal relationships (15.5% vs. 36.0%, p<0.001) and work output (16.8% vs. 36.0%; p<0.001). Of the group followed up, 49 returned surveys and 33 who were using continuous positive airway pressure (CPAP) showed significant improvements between the initial and second follow-up in time management (26% vs. 9%, p=0.0005), mental-interpersonal relationships (16% vs. 11.0%, p=0.014) and work output (18% vs. 10%; p<0.009).

CONCLUSION

We have demonstrated a clear relationship between excessive sleepiness and decreased work productivity in a population referred for suspected sleep-disordered breathing. Screening for sleepiness and sleep-disordered breathing in the workplace has the potential to identify a reversible cause of low work productivity.

Pulmonary actinomycosis complicating infliximab therapy for Crohn's disease

The use of anti-tumour necrosis factor (TNF) agents has expanded significantly over the past few years, particularly for rheumatological diseases and Crohn's disease. A number of associated opportunistic infections have been observed as a result of suppression of T cell-mediated immunity, the most frequent being tuberculosis. We report the first case of pulmonary actinomycosis in a patient receiving regular infusions of infliximab, an anti-TNF agent, for Crohn's disease.

Adverse drug reactions associated with first-line anti-tuberculosis drug regimens

BACKGROUND

Standard treatment of active tuberculosis (TB) consists of isoniazid (INH), rifampin (RMP), pyrazinamide (PZA) and ethambutol (EMB). Although this regimen is effective in treating active TB, it is associated with many adverse drug reactions (ADRs) and poses a significant challenge to completion of treatment.

OBJECTIVES

To examine the incidence of major ADRs and risk factors associated with first-line anti-tuberculosis medications.

METHODS

This study evaluated patients receiving treatment for active TB from a population-based database (2000-2005). The nature of the ADRs, likelihood of association with the study medications and severity were evaluated.

RESULTS

A total of 1061 patients received treatment, of whom 318 (30%) had at least one major ADR. The overall incidence of all major ADRs was 7.3 events per 100 person-months (95%CI 7.2-7.5): 23.3 (95%CI 23.0-23.7) when on all four first-line drugs, 13.6 (95%CI 13.3-14.0) when on RMP, INH and PZA, and 2.4 (95%CI 2.3-2.6) when on INH and RMP. Adjusted hazard ratio (HR) revealed that combination regimens containing PZA, females, subjects aged 35-59 and >or=60 years, baseline aspartate aminotransferase >or=80 U/l and drug resistance were associated with any major event.

CONCLUSIONS

First-line anti-tuberculosis drugs are associated with significant ADRs. There are several risk factors associated with the development of ADRs, including exposure to regimens containing PZA.

BCG vaccination and the prevalence of latent tuberculosis infection in an aboriginal population

SETTING

Estimations of prevalence of latent tuberculous infection (LTBI) are confounded by factors known to influence the results of the tuberculin skin test (TST) such as age, contact history and bacille Calmette-Guerin (BCG) vaccination. Appropriate interpretation of TST results is necessary to ensure LTBI treatment for those at greatest risk.

OBJECTIVE

To document the prevalence of LTBI in Aboriginal people living on a reserve in British Columbia (BC) and to determine the influence of BCG.

DESIGN

A population-based, retrospective descriptive analysis of all epidemiological data collected for the on-reserve Aboriginal programme in BC (1951-1996).

RESULTS

Of 17615 persons who received a TST during the study period, 42% had received BCG. During the study period, an average of 2517 TSTs were completed per year (SD = 1228) among persons with an average age of 26 years (SD = 16). Among all subjects, the average prevalence of LTBI was 25% (95 %CI 24-25). The presence of BCG (OR = 3.1, 95%CI 2.8-3.4) and multiple BCGs (OR = 10.2, 95%CI 7.7-13.6) were both associated with a positive TST. A positive TST was also associated with a shorter duration in years between the most recent BCG and the TST.

CONCLUSION

The average prevalence of LTBI in a sequential sample of Aboriginal people living on a reserve in BC was estimated at 25%. BCG, especially in multiple doses, increased the likelihood of a positive TST.

A systematic review of the psychological risk factors associated with near fatal asthma or fatal asthma

Psychological factors such as anxiety, depressive disorders and/or personality disorders may predispose patients with asthma to near fatal asthma (NFA) or fatal asthma (FA). NFA is defined by an asthma exacerbation resulting in respiratory arrest requiring mechanical ventilation or a pCO(2) >or=45 mm Hg. Most studies have used the case-control study design. Several studies analyzing the effects of psychological factors on the risk of NFA or FA have shown conflicting results. We reviewed all of the literature found by the systematic search done of psychological factors on the risk NFA or FA. A MEDLINE search identified 423 articles between 1960 and March 2006. Seven case-controlled studies were identified following strict applications of the inclusion and exclusion criteria. Due to the significant heterogeneity in the measurement of the psychological factors, a summary statistic was not calculated. The trial characteristics were tabulated and qualitative trends were observed to explain the heterogeneity in the results of the studies. Recommendations on future studies in the field are outlined in detail. Following a systematic assessment of all published studies, we cannot conclude that psychological factors increase the risk of NFA and FA.

The assessment and management of patients with acute asthma

Acute asthma is a common medical emergency that is often poorly assessed and managed. Initial evaluation should include a review of historical factors for identifying high risk patients; appropriate evaluation of the current exacerbation, including an objective assessment of airflow obstruction; and, in parallel, initiation of therapy with controlled oxygen therapy, regular bronchodilator therapy and, in most cases, systemic corticosteroids. There is no benefit in using intravenous (IV) corticosteroids--a single 50 mg oral dose is appropriate. Although there is no significant additional bronchodilator effect with the use of ipratropium bromide or IV magnesium, both modalities have been shown to reduce hospitalisations for moderate to severe exacerbations. There is no role for the routine use of IV aminophylline or beta (beta) agonists in patients presenting with acute asthma. Patients who achieve 60% of their predicted peak expiratory flow (PEF) or 1 sec forced expiratory volume (FEV1) or best can usually be safely discharged. The exacerbation should be taken as an opportunity to review how a patient responded to the particular exacerbation. Were they on appropriate anti-inflammatory therapy? Did they modify the dose of therapy early in the exacerbation? Did they have an action plan? Such deficiencies can usually be managed by facilitated referral to a specialist clinic that ideally has an asthma education programme. The need for long-term anti-inflammatory therapy can be reviewed at this time as well as the potential incremental benefit of the addition of add-on therapy, most likely the use of a long-acting beta agonist.

Pithomycotoxicosis (facial eczema) in ruminants in the Azores, Portugal

Outbreaks of pithomycotoxicosis (facial eczema), a hepatogenous photosensitisation caused by the mycotoxin sporidesmin, have affected ruminants in the Azores Islands of Portugal after warm, humid periods during late summer and autumn. Twenty-two outbreaks were recorded in cattle between 1999 and 2001, affecting 11.4 per cent of the animals in the affected herds, and in 2000 there was an outbreak in one sheep flock in which more than 20 per cent of the sheep died. The clinical signs included decreases in milk production, weight loss, photosensitisation and its sequelae, including death. The animals had high activities of gamma glutamyltransferase in their serum, and icterus and severe liver disease, including biliary hyperplasia and fibrosis, were found postmortem. The characteristic spores of the toxigenic saprophytic fungus Pithomyces chartarum were found on grass; all 381 isolates of the fungus were toxigenic for sporidesmin by elisa, and the results were confirmed by high-performance liquid chromatography analysis. Cattle from farms at greatest risk of pithomycotoxicosis were protected by supplementing their concentrate feed with zinc oxide, or using a slow-release intraruminal zinc bolus.

A systematic review of risk factors associated with near-fatal and fatal asthma

BACKGROUND

Asthma mortality and morbidity continue to be a serious global problem. Systematic reviews provide an opportunity to review risk factors in detail.

OBJECTIVE

To review all of the literature for risk factors associated with near-fatal asthma (NFA) and fatal asthma (FA).

METHODS

A literature search from 1960 to January 2004 in MEDLINE and EMBASE was conducted. Studies were included based on the following criteria: NFA was defined as an asthma exacerbation resulting in respiratory arrest requiring mechanical ventilation or a partial pressure of CO2 of at least 45 mmHg or asthma resulting in death (FA); the study reported the number of cases (NFA and/or FA) and asthmatic controls; there was explicit reporting of risk factors; cases that were adult and pediatric in nature; and all study types. Studies that included patients with chronic obstructive pulmonary disease were excluded.

RESULTS

Four hundred and three articles were identified, of which 27 met the inclusion criteria. Increased use of medications such as beta-agonists via metered dose inhalers (OR=1.67, 95% CI 0.99 to 2.84, P=0.057) and nebulizers (OR=2.45, 95% CI 1.52 to 3.93, P=0.0002), oral steroids (OR=2.71, 95% CI 1.34 to 5.51, P=0.006) and oral theophylline (OR=2.02, 95% CI 1.03 to 3.98, P=0.04) and a history of hospital (OR=2.62, 95% CI 1.04 to 6.58, P=0.04) and/or intensive care unit (OR=5.14, 95% CI 1.91 to 13.86, P=0.001) admissions and mechanical ventilation (OR=6.69, 95% CI 2.80 to 15.97, P=0.0001) due to asthma were predictors of NFA and FA. Prior emergency department assessment did not confer a greater risk of NFA and FA (OR=1.13, 95% CI 0.43 to 2.92, P=0.810). The use of inhaled corticosteroids (ICS) measured in a dose-independent fashion (did the patient take ICS previously; yes or no) inferred equivocal risk of NFA and FA (OR=1.31, 95% CI 0.83 to 2.05, P=0.25). However, two studies measured the use of ICS in a dose-dependent fashion (ie, measured the number of prescriptions filled within the previous six to 12 months). Both studies showed a trend toward a protective effect against FA. One study showed that the premature cessation of ICS can hasten death.

CONCLUSIONS

In the present study, risk factors of NFA and FA have been more accurately defined. Clinicians should identify patients with these characteristics to reduce their risk of NFA and FA. Further research should focus on quantifying the impact of risk factors on asthma deaths.

Massive haemolysis in a group A recipient of a group O peripheral blood stem cell allogeneic transplant

A 28-year-old man with lymphoblastic lymphoma received G-CSF mobilized stem cells from his HLA identical sister, who had been taking methotrexate for psoriasis until 1 month prior to harvest. The recipient's blood group was A Rh D positive and donor's group O Rh D positive. Engraftment and major haemolysis were evident by day 9. From day 9 to day 13 he received 17 units of blood (approximately 3 L of red cells) at a time when his calculated red cell volume was 1 L. This massive transfusion requirement was not explained by his clinical condition and led us to consider factors that may have influenced the degree of haemolysis. The stem cell graft contained 2.85 x 10(6) CD34+ cells kg(-1) and we speculate there was B cell hyperactivity following the withdrawal of methotrexate in the donor and this went unchecked by the omission of methotrexate in the GVHD prophylaxis of the recipient. We have also considered the phenomenon of bystander haemolysis, previously unreported in this situation, as haemolysis of transfused group O blood must have also occurred. The case also illustrates the importance of transfusing donor type red cells and recipient type fresh frozen plasma (FFP) and platelets into minor mismatched transplant patients. The decision to revert to donor type FFP and platelets should only be made when the direct antiglobulin test is negative and the appropriate isohaemagglutinins are no longer demonstrable.

The role of the C-C chemokine receptor-5 Delta32 polymorphism in asthma and in the production of regulated on activation, normal T cells expressed and secreted

BACKGROUND

There are conflicting data regarding the role of a deletion in the C-C chemokine receptor-5 gene (CCR5*D32) in the pathogenesis of asthma and whether this deletion influences the production of regulated on activation, normal T cells expressed and secreted (RANTES). RANTES is a chemokine that is known to play an important role in the pathogenesis of allergic asthma.

OBJECTIVE

We sought to determine whether CCR5*D32 is associated with increased RANTES production, the presence of asthma, and the severity of asthma.

METHODS

A PCR assay for CCR5*D32 was developed. The prevalence of CCR5*D32 was determined in a group of patients with mild-to-moderate asthma, a group of subjects with severe asthma who had fatal or near-fatal asthma attacks, and a group of nonasthmatic control subjects. The level of RANTES produced by stimulated and unstimulated T cells was measured by using a commercially available immunoassay.

RESULTS

The frequency of CCR5*D32 was not significantly increased in the severe asthma group compared with in the mild-to-moderate asthma group. CCR5*D32 was not increased in the asthmatic subjects versus in the control subjects. There was no significant increase in RANTES levels from T cells heterozygous for CCR5*D32 compared with wild-type cells.

CONCLUSION

These data indicate that the CCR5*D32 allele is not a genetic risk factor for the development of asthma and does not influence disease severity. The CCR5*D32 allele does not influence RANTES production in the heterozygous state.

Evaluation of incidental renal and adrenal masses

Incidental renal or adrenal masses are sometimes found during imaging for problems unrelated to the kidneys and adrenal glands. Knowledgeable family physicians can reliably diagnose these masses, thereby avoiding unnecessary worry and procedures for their patients. A practical and cost-efficient means of evaluating renal lesions combines ultrasonography and computed tomographic scanning, with close communication between the family physician and the radiologist. Asymptomatic patients with simple renal cysts require no further evaluation. Patients with minimally complicated renal cysts can be followed radiographically. Magnetic resonance imaging is indicated in patients with indeterminate renal masses, and referral is required in patients with symptoms or solid masses. The need for referral of patients with adrenal masses is determined by careful assessment of clinical signs and symptoms, as well as the results of screening laboratory studies and appropriate radiologic studies. Referral is indicated for patients with incidental adrenal masses more than 6 cm in greatest diameter. Appropriate laboratory screening tests include the following: a 24-hour urinary free cortisol measurement for patients with evidence of Cushing's syndrome; a 24-hour urinary metanephrine, vanillylmandelic acid or catecholamine measurement for patients with evidence of pheochromocytoma; and a serum potassium level for patients with evidence of hyperaldosteronism.

Younger and older jurors: the influence of environmental supports on memory performance and decision making in complex trials

This study compared memory and decision making by younger (aged 19-35) and older (aged 55-75) adults who had viewed a 2-hr video of a complex civil trial. Participants were tested for free recall, recognition memory, source identification, and the accuracy of their verdicts. The experiment manipulated (a) note taking during the trial and (b) timing of judicial instructions: either before (preinstructed) or after (standard) the presentation of relevant evidence. Judicial instructions provide jurors with a framework for understanding legal concepts such as liability and compensatory damages. Both younger and older adults provided more detailed and cohesive accounts when they were given judicial instructions before the evidence. Other benefits of preinstruction to memory and decision making were limited to older adults. Note-taking effects were generally limited but were consistent across age groups. The results highlight the potential value of relatively simple interventions for improving cognitive performance in a real-world setting.

Polymorphisms in the IL4, IL4RA, and FCERIB genes and asthma severity

BACKGROUND

Genetic polymorphisms have been associated with asthma and asthma severity.

OBJECTIVE

We sought to determine whether 3 polymorphisms were associated with severe asthma indicated either by the occurrence of a fatal (or near-fatal) asthma attack or by severe airflow obstruction.

METHODS

We obtained DNA and clinical data from asthmatic subjects who either died or nearly died during an asthma attack and from a group of subjects with mild-to-moderate asthma who had never experienced a fatal or near-fatal asthma episode. These groups were compared with a group of nonatopic nonasthmatic control subjects. The level of airflow obstruction (FEV(1) percent predicted) in the subjects with mild-to-moderate asthma was used as an additional measure of disease severity. The subjects were genotyped for the IL4*C-589T promoter polymorphism and the IL4RA*Q576R and the FCERIB*E237G amino acid substitutions.

RESULTS

The results showed that the FCERIB*E237G and IL4RA*Q576R polymorphisms were not associated with fatal or near-fatal asthma. However, the IL4*-589T allele was significantly increased in the subjects with fatal or near-fatal asthma compared with nonasthmatic subjects (odds ratio [OR], 1.8; P =.02) and subjects with mild-to-moderate asthma (OR, 1.9; P =.02). There was no interaction between the IL4*-589T and IL4RA*576R alleles. Of the 3 polymorphisms, only the IL4RA*576R allele was associated with severe airflow obstruction (OR, 8.2; P =.01).

CONCLUSION

These data suggest that the IL4*-589T allele is a risk factor for life-threatening asthma and that the IL4RA*576R allele is a risk factor for a low level of lung function in asthmatic subjects.

Prevalence of tumor necrosis factor-alpha and angiotensin converting enzyme polymorphisms in mild/moderate and fatal/near-fatal asthma

Allele 2 of the polymorphism at position -308 in the promoter of the tumor necrosis factor alpha (TNF-alpha) gene, and the D allele of the angiotensin converting enzyme (ACE) gene, have been associated with asthma. We hypothesized that genotypes containing these alleles would show an increased prevalence in asthmatic as compared with nonasthmatic individuals, and would be associated with asthma severity. Polymerase chain reaction-based assays were developed to determine TNF-alpha and ACE genotypes among subjects with mild/moderate asthma (n = 92), fatal/near-fatal asthma (n = 159), no asthma (n = 43), and random population controls (n = 252). The TNF-alpha -308 polymorphism was increased in both subjects with mild/moderate (p = 0.03) and those with fatal/near fatal asthma (p = 0.02) versus those without asthma, and in all subjects with asthma versus random population controls (p = 0.02). The mild/moderate group was subdivided into subjects with mild (n = 43) and those with moderate (n = 33) asthma. TNF-alpha -308 was increased in the moderately asthmatic versus the nonasthmatic subjects (p = 0.003), and in the mildly asthmatic subjects (p = 0.01). However, TNF-alpha -308 was not significantly more prevalent in the fatal/near-fatal than in the mild/moderate asthmatic group. The ACE-D allele did not show an association with either asthma or asthma severity. We conclude that the TNF-alpha -308 polymorphism may be a risk factor for asthma but does not increase the risk of a fatal or a near-fatal asthma attack, whereas the ACE polymorphism is not associated with asthma in this population.

beta2-Adrenergic receptor haplotypes in mild, moderate and fatal/near fatal asthma

Excess beta2-agonist use in asthmatics has been associated with increased mortality and morbidity. The mechanisms responsible for these observations are unknown. We hypothesized that polymorphisms of the beta2-adrenergic receptor (beta2AR) at amino acid positions 16, 27, and 164, which are known to alter receptor functions in vitro, may predispose asthmatics to fatal/near-fatal asthma and/or modify asthma severity. In preliminary studies we found significant differences in allele frequencies due to ethnic background: Caucasian, Black, Asian Gly16 = 0.61, 0.50, 0.40 and Gln27 = 0.57, 0. 73, 0.80, respectively. beta2AR genotyping was performed on DNA from Caucasians classified as nonasthmatic/nonatopic (n = 84), fatal/near-fatal asthmatics (n = 81) and mild/moderate asthmatics (n = 86). No polymorphism or haplotype was found to be associated with fatal/near-fatal asthma. However, the Gly16/Gln27 haplotype, which undergoes enhanced downregulation in vitro, was substantially more prevalent in moderate asthmatics than in mild asthmatics (p = 0.003, odds ratio = 3.1). We conclude that the beta2AR genotype is not a major determinant of fatal or near-fatal asthma. Furthermore, allele frequency variation among ethnic groups must be considered in clinical studies of beta2AR polymorphisms in asthma.

The effect of adding ipratropium bromide to salbutamol in the treatment of acute asthma: a pooled analysis of three trials

OBJECTIVE

To assess the effect on FEV1 and clinical outcomes of adding ipratropium bromide to salbutamol in the treatment of acute asthma.

METHODS

We conducted a pooled analysis of three randomized double-blinded clinical trials conducted in the United States, Canada, and New Zealand. The studies enrolled 1,064 patients aged 18 to 55 years who presented at the emergency department with acute asthma. Patients were randomized to treatment with a combination of nebulized 2.5 mg salbutamol plus 0.5 mg ipratropium bromide, or 2.5 mg salbutamol alone. Medications were administered at baseline and, in the US study, at 45 min. FEV1 was measured at baseline, 45 min, and 90 min. Patients were followed up for 48 h after hospital discharge for occurrence of asthma exacerbation and hospitalization.

RESULTS

Treatment groups were comparable at baseline. Of the 1,064 patients randomized, 1,015 patients (95%) remained in the study for measurement at 45 min, and 961 patients (90%) completed the final measurement at 90 min. Comparison of overall improvement in FEV1 at 45 min indicated a better response for patients receiving combination therapy (mean difference=43 mL, 95% confidence interval [CI]=-20, 107). The distribution of change in FEV1 was skewed by a small number of patients with extreme values (38 of 1,064=3.6%) that may have been due to unreliable lung function testing. Removing these outliers produced a larger and more precise estimate of effect (mean difference=55 mL, 95% CI=2,107). Because the distribution was skewed, we performed nonparametric analyses that showed evidence of a beneficial effect of combination therapy. The difference between median values at 45 min is 40 mL (Wilcoxon p value=0.03). In addition, 4.9% (95% CI=-1%, 11%) more patients in the combination group achieved at least 20% of their potential improvement, as measured by the difference between their baseline FEV1 and their predicted FEV1. Patients receiving combination therapy had lower risk for each of three clinical outcomes: the need for additional treatment (relative risk [RR]=0.92, 95% CI=0.84, 1.0), risk of asthma exacerbation (RR=0.84, 95% CI=0.67, 1.04), and risk of hospitalization (RR=0.80, 95% CI=0.61, 1.06).

CONCLUSION

Adding ipratropium bromide to salbutamol in the treatment of acute asthma produces a small improvement in lung function, and reduces the risk of the need for additional treatment, subsequent asthma exacerbations, and hospitalizations. These apparent benefits of adding ipratropium bromide were independent of the amount of beta-agonist that had been used earlier in the attack, and possibly related to a recent upper respiratory tract infection. Confirmatory studies are needed, especially for clinical outcomes.

Risk factors for near-fatal asthma. A case-control study in hospitalized patients with asthma

We prospectively recruited patients admitted to the hospital with severe asthma to comprehensively evaluate the association of historical and physiologic features with the risk of near-fatal asthma (NFA). A case-control study design was used. All patients admitted with NFA (cases) were identified prospectively and compared with asthma patients admitted during the same period without respiratory failure (controls). Nineteen cases (age: 40.2 +/- 12.0 yr) (mean +/- SD) and 80 controls (age: 36 +/- 13.5 yr) were enrolled. Duration of asthma, gender, smoking status, ethnicity, and prevalence of atopy were similar in the case and control groups. More than 80% of patients in both groups reported worsening symptoms for more than 48 h before admission, and more than 50% were worse for longer than 7 d. There was no difference in degree of airways obstruction or bronchial hyperresponsiveness (PC20). Perception of dyspnea was similar in the cases and controls, but among cases the males had greater impairment than the females (Borg score: 1.9 +/- 1. 4 versus 3.9 +/- 1.2: p = 0.05). Univariate analysis identified a history of previous mechanical ventilation (OR: 27.5; 95% CI: 6.60 to 113.7), admission to the intensive care unit (ICU) (OR: 9.9; 95% CI: 3.0 to 32.9), history of worse asthma during January and February (OR: 3.5; 95% CI: 1.0 to 11.8), and use of air-conditioning (OR: 15.0; 95% CI: 1.3 to 166) as risk factors for NFA. Of concern was the dependence of most patients (59.8%) on the emergency department (ED) for initial care, and the small number of cases (16%) in which patients visited a physician before admission to the hospital. We have confirmed risk factors identified previously in retrospective studies of fatal and NFA, and have also shown that hospitalized patients with asthma, irrespective of severity of their asthma, share several characteristics, especially in terms of their failure to respond to worsening asthma.

A randomized trial comparing peak expiratory flow and symptom self-management plans for patients with asthma attending a primary care clinic

Great emphasis is placed on educating asthmatics to use action plans to achieve better control of symptoms. The use of peak flow meters (PFM) has been recommended as an important part of self-management plans. We studied 92 (47 F) adult patients with asthma in a primary care setting to compare the effectiveness of action plans using either peak flow monitoring or symptoms to guide self-management. Each patient was instructed in the use of the action plan in the context of a 6-mo asthma education program taught by a nurse. Patients were already using inhaled corticosteroids or were newly prescribed corticosteroids by their family physician. Forty-four patients were randomized to the PFM group and 48 to the symptoms group. Spirometry, symptom scores, quality of life, medication use, and measures of health care utilization and morbidity (emergency department visits, hospitalizations, unscheduled doctor visits, and days lost from work or school) were recorded at baseline and throughout the study period. PC20 methacholine was measured at the first and at the final visits. There were significant improvements within groups for FEV1, symptoms score, PC20 methacholine, and quality of life, but no between-group differences. A significant shift from higher to lower daily use of beta-agonists (p < 0.008 for both groups) and significant shifts to higher daily doses of inhaled steroids (p < 0.001) occurred in each group. Adherence to the self-management plans was only 65% in the PFM group and 52% in the symptoms group. Outcomes for health care utilization were similar except for fewer patients making unscheduled doctor visits within the PFM group. Our findings show that education, regular follow-up, and an action plan are effective in improving asthma control and quality of life, but the routine use of PFM to guide interventions is not the only way to accomplish these objectives.

Biological control of sporidesmin-producing strains of Pithomyces chartarum by biocompetitive exclusion

The feasibility of using atoxigenic strains of Pithomyces chartarum for the biological control of toxigenic strains of P. chartarum was examined. Pasture, treated with atoxigenic strains of P. chartarum, contained up to 80% less sporidesmin than found in untreated pasture. Maximum sporidesmin levels of 26 ng g-1 grass in treated pasture and 113 ng g-1 grass in untreated pasture (means of 24 and four plots, respectively) were recorded 14 weeks after treatment, when spore numbers had reached a maximum of 80,000 spores g-1 grass in the untreated plots and 50,000 spores g-1 grass in the treated plots. This trial demonstrated that sporidesmin-producing spores of P. chartarum could be successfully reduced in pasture by the addition of atoxigenic strains, thereby reducing the risk of facial eczema in livestock.

Development of PCR-SSOP for the identification of HLA-A*02 subtypes and determination of HLA-A*02 frequencies within different ethnic populations

A PCR-SSOP typing method, involving a single PCR amplification in conjunction with 19 digoxigenin labelled oligonucleotide probes, has been developed for the identification of 17 known HLA-A*02 alleles. The method has been applied to four populations (Northern Ireland, Singapore Chinese, Shetland Island and Mexican) and percentages of HLA-A*02 alleles determined within each population.

Human bladder carcinoma cell lines as indicators of oncogenic change relevant to urothelial neoplastic progression

Analysis of human tumour-derived cell lines has previously resulted in the identification of novel transformation-related elements and provided a useful tool for functional studies of different genes. To establish the utility of such cell lines as indicators of change relevant to urothelial cancer, we have characterised the expression of five genes (p53, MDM2, Rb, E-cadherin, APC) within a panel of human bladder carcinoma cell lines. Using single-strand conformation polymorphism (SSCP) and direct sequencing, p53 mutations were identified in 7/15 (47%) cell lines reflecting events reported in bladder tumours. Immunohistochemical analysis of p53 in cultured cells and in paraffin-embedded sections of xenografts from the cell line panel revealed discordant results. An absence of p53 nuclear staining was associated with an exon 5 mutation in EJ and with multiple p53 mutations found in J82. Two cell lines positive for p53 staining in the absence of detectable mutation displayed overexpression of MDM2 (PSI, HT1197) in Western blot analysis. Loss or aberrant Rb expression was recorded in 5/15 (TCCSUP, SCaBER, 5637, HT1376, J82) cell lines. Absence of E-cadherin was recorded in 5/15 cell lines (TCCSUP, EJ, KK47, UM-UC-3, J82) with loss of alpha-catenin in immunoprecipitated E-cadherin complexes of CUBIII. Western blot analysis of APC revealed a truncated protein in 1/15 (CUBIII) cell lines. The characterisation of oncogenic events within this panel of human bladder carcinoma cell lines establishes a representation of change observed in bladder tumours and better defines the genotypic background in these experimental human cell models of neoplastic progression.

Tuberculosis in the 1990s. Issues for primary care physicians

After declining for many years, tuberculosis rates have begun to level off in Canada. Groups at particularly high risk include aboriginal Canadians, immigrants from high-prevalence countries, HIV-infected people, and elderly men. If disease is suspected, appropriate investigations, including sputum tests for bacteriology and chest x-ray examinations, should be done. Response to treatment is excellent. Chemoprophylaxis is recommended for certain patients. Vaccination with BCG has a limited but important role, especially for aboriginal Canadians.

Identification of H-ras mutations in urine sediments complements cytology in the detection of bladder tumors

BACKGROUND

Urinary cytology has long been used as a noninvasive screen for the detection of urinary tract cancer but is limited by the generation of false positive and false negative results. More recently, molecular changes associated with urothelial neoplastic progression have been identified in DNA from urine sediments, demonstrating an alternative approach for identifying neoplastic change in the bladder.

PURPOSE

The purpose of this prospective study was to determine the value of detection of H-ras (also known as HRAS) mutations in urine sediment DNA as a clinical indicator of tumor presence, recurrence, and/or progression.

METHODS

Urine sediments were collected from 100 patients presenting with bladder tumors, with follow-up samples collected from 19 patients. DNA extracted from urine sediments was analyzed for changes in exon 1 of the H-ras gene, using single-strand conformation polymorphism (SSCP) analysis. A representative number of aberrant H-ras/SSCP migrating bands were excised and sequenced to confirm the presence of a mutation. Human bladder specimens were obtained from patients (93 of the 100 patients initially and 18 of the 19 patients studied by follow-up) and histologically evaluated for tumor content and grade.

RESULTS

Mutations in exon 1 of the H-ras gene were detected in urine sediments from 44% (44 of 100) of the patients; concordant results were obtained by cytologic analysis, where 33% (31 of 93) of the patients displayed positive cytology. Analysis of the distribution of abnormalities with tumor grade revealed greater detection of low-grade (1-2) lesions using ras analysis (47%) compared with cytology (16%). In contrast, cytology was more effective in identifying the presence of carcinoma in situ. Combined results from these two approaches substantially increased the sensitivity of tumor detection, resulting in the identification of tumors in 60% of patients.

CONCLUSIONS

Identification of H-ras mutations in DNA from urine sediments facilitates the detection of low-grade bladder tumors and, in combination with cytology, increases the overall tumor detection from 33% to 60%. Preliminary results in patient follow-up suggest that detection of H-ras mutations may have some clinical utility in detecting the presence of abnormal cells in the absence of an overt lesion following cystoscopy or positive cytology.

A mathematical model for the prediction of the impact of HIV infection on tuberculosis

A mathematical model is introduced to study the accelerating impact of HIV infection on the incidence rates of tuberculosis (TB) disease. A sexually active population (15-49 years) is followed cross-sectionally over a period of time. Beginning with the year in which HIV infection was probably first present in the population, the model calculates the growing yearly incidence rates of new TB disease in HIV-positive and in HIV-negative individuals. Model equations, derived by an actuarial method, are developed recursively. Input information required for the calculations includes the age distribution of the study population, pre-HIV annual TB infection rates, annual HIV infection and mortality rates, and estimates of annual TB disease breakdown rates in the absence and in the presence of HIV infection. With correct input data, the model provides a useful blueprint for health agencies in designing effective programmes for curbing the future course of these dual epidemics in the population.

Incorrect positioning of nasogastric feeding tubes and the development of pneumothorax

The authors describe 12 patients in whom feeding tubes were inadvertently placed in the bronchial tree a total of 14 times. All but four of the misplacements were complicated by pneumothorax. No deaths were directly attributable to the misplacements, although one cardiac arrest occurred as a late complication of intrapleural feeding. Careful, controlled insertion of feeding tubes and radiographic confirmation of their placement are essential to reduce morbidity and mortality.

An estimate of the future size of the tuberculosis problem in sub-Saharan Africa resulting from HIV infection

The impact of the human immunodeficiency virus (HIV) on tuberculosis is well documented. Its effect in populations with a high proportion of dually infected individuals is likely to be significant. Sub-Saharan Africa is one such region and to better document the effect of HIV infection on tuberculosis there we developed a mathematical model to predict the likely extra numbers of tuberculosis cases due to it. A mathematical model was developed using a variety of scenarios giving a range of risks for the period 1980-2000. The four scenarios included (1) a low rate of 1% risk of tuberculosis infection in year 0 (1980) with 45% tuberculosis infection prevalence, and an HIV prevalence of 2% in 1989; (2) a 2% risk of tuberculosis infection in year 0 with 60% tuberculosis infection prevalence, and a 2% HIV prevalence in 1989; (3) a 2% risk of tuberculosis infection in year 0 with 60% tuberculosis infection prevalence, and a 10% HIV prevalence in 1989; and (4) a 2% risk of tuberculosis infection in year 0 with 60% tuberculosis infection prevalence and a 20% HIV prevalence in 1989. Under scenarios 1 and 2, a 50-60% increase in smear-positive rates in the subpopulation (15-45 years old) is predicted for the year 2000, under scenario 3, smear-positive rates in the subpopulation in the year 2000 are expected to increase four-fold from the 1980 baseline. Under scenario 4, a 10-fold increase in smear-positive rates in 2000 is expected in the subpopulation. Under this scenario, total disease will have increased 12-fold in the subpopulation.(ABSTRACT TRUNCATED AT 250 WORDS)

A just alternative. Church tribunals may be the best forum for settling wrongful discharge disputes

The threat of a wrongful discharge lawsuit should be a concern for every employer. However, Church employers can minimize their risk if they follow Church teaching in their employment practices and policies and if they use the Church tribunal system to settle employer-employee disputes. As it originally developed in common law, the "employment-at-will" concept stipulated that an employer could discharge an employee at any time, for any reason, or for no reason at all. Most states have adopted this common law concept, although courts and legislatures have created a number of exceptions to it. Despite these exceptions, employment-at-will has proven to be a powerful tool in the hands of employers. However, employees of Church institutions who feel they have been discharged wrongfully can turn to Church tribunals, which are governed by canon law. A Church tribunal can do virtually anything a civil court can do, with the exception of ordering someone to jail. Moreover, because the standards of justice and equity applied by Church tribunals are stricter than those applied by American courts, employees of Catholic institutions in the United States may make increasing use of them in the future. Disputes that come before a Church tribunal will be settled by either arbitration or mediation. Arbitration is a kind of informal litigation. Mediation, however, is preferable because it forces the parties involved to examine themselves, their motives, and their effects on each other and the Church as a whole.

Evaluation of the protected brush catheter and bronchoalveolar lavage in the diagnosis of nosocomial pneumonia

We assess the sensitivity and specificity of the protected brush catheter (PBC) and bronchoalveolar lavage (BAL) in diagnosing nosocomial pneumonia in nonimmunocompromised critically ill patients. Computerized bibliographic literature searches of MEDLINE were performed, and the reference list of each article selected was reviewed. Of 496 citations, there were 19 articles (describing 18 studies) that proved relevant. Study quality was assessed, and descriptive information concerning study populations, interventions, and clinically relevant outcome measurements was extracted. The sensitivity and specificity of PBC were high (pooled estimates, 89.9 and 94.5%, respectively). Criteria for a positive BAL have varied between studies, and sensitivity ranged from 53.3 to 100%, whereas specificity was 98.6%. Most studies did not report whether antibiotics were withheld on the basis of negative test results. In those that did, the incidence of adverse outcomes consequent on withholding antibiotics was low. BAL and PBC, combined with the use of quantitative cultures, appear to increase accuracy in diagnosing pneumonia. The strength of inference is hampered, however, by the absence of a "gold standard" for the diagnosis of pneumonia. Moreover, the generalizability of these findings is limited by the fact that there are so few methodologically sound studies from so few centers. A randomized trial of PBC is needed.

A developmental account of early childhood amnesia

This study was an attempt to demonstrate the utility of a developmental approach to the study of early childhood amnesia. Working from a model of early childhood memory development proposed by Nelson and Ross (1980), I hypothesized that children would show early childhood amnesia and that this could be tested by comparing obtained estimates of memory strength to values predicted by a standard retention function. The data confirm this hypothesis for 6- and 10-year-old children, and suggest that the early childhood amnesia period extends from birth to a point between the third and fourth birthdays. The data also support a prediction, derived from the aforementioned model, that children would report a disproportionate number of general memories from the amnesia period. Thus, the developmental model provides a useful vehicle for examining early childhood amnesia and helps to frame further questions such as why some specific memories from this period are retained even though most are lost.

Mesalamine in ulcerative colitis

Sulfasalazine has been used for many years in the management of ulcerative colitis. As many as 20 percent of patients treated with it experience intolerable adverse effects usually attributed to its sulfapyridine component. The other active component is 5-aminosalicylic acid (5-ASA); the only 5-ASA enema preparation currently available in the U.S. is mesalamine (Rowasa, Reid-Rowell) containing 5-ASA 4 g in 60 mL. In clinical trials, mesalamine has proved efficacious in treating refractory cases of distal ulcerative colitis, proctitis, and proctosigmoiditis. Because of its high cost compared with more conventional treatment modalities, it should be reserved for cases that are either refractory or intolerant to conventional treatment.

Adenosine deaminase in the diagnosis of tuberculous pleural effusions. A report of 218 patients and review of the literature

The activity of adenosine deaminase in the pleural fluid of 218 consecutive patients was studied. According to the etiology of exudative pleural effusions, the patients were divided into the following five groups: (1) tuberculosis; (2) lung cancer; (3) pneumonias; (4) miscellaneous; and (5) idiopathic. Patients with pleural tuberculosis presented significantly higher ADA activity than patients with nontuberculous pleural effusions (p less than 0.0001). The results indicated that in a population with a relatively high prevalence of tuberculosis, the analysis of ADA levels in pleural effusions constitutes a useful marker for the diagnosis which, in addition, can be made quickly and cheaply. Additionally, a comprehensive review of the literature on the role of ADA in the diagnosis of tuberculous pleural effusions is presented.