Using systems thinking-based risk assessment methods to assess hazardous manual tasks: a comparison of Net-HARMS, EAST-BL, FRAM and STPA

Formal risk assessment is a component of safety management relating to hazardous manual tasks (HMT). Systems thinking approaches are currently gaining interest for supporting safety management. Existing HMT risk assessment methods have been found to be limited in their ability to identify risks across the whole work system; however, systems thinking-based risk assessment (STBRA) methods were not designed for the HMT context and have not been tested in this area. The aim of this study was to compare the performance of four state-of-the-art STBRA methods: Net-HARMS, EAST-BL, FRAM and STPA to determine which would be most useful for identifying HMT risks. Each method was independently applied by one of four analysts to assess the risks associated with a hypothetical HMT system. The outcomes were assessed for alignment with a benchmark analysis. Using signal detection theory (SDT), overall STPA was found to be the best performing method having the highest hit rate, second lowest false alarm rate and highest Matthews Correlation Coefficient of the four methods.Practitioner summary: A comparison of four systems thinking risk assessment methods found that STPA had the highest level of agreement with the benchmark analysis and is the most suitable for practitioners to use to identify the risks associated with HMT systems.

The early intervention message: perspectives of parents of children with autism spectrum disorder

BACKGROUND

There is strong evidence that early intervention (EI) can improve outcomes for children with autism spectrum disorder (ASD), and consequently, the importance of EI has been widely promoted to families of children with ASD. However, the perspectives of parents of children with ASD regarding the EI message have not been widely examined.

METHODS

This study used qualitative methods to explore parental perspectives on the EI message. Semi-structured interviews were undertaken with 14 participants from 12 family units to explore the perspectives of parents of children with ASD on the EI message. Thematic analysis was undertaken on the data.

RESULTS

Three central themes were constructed following data analysis: (i) parents' initial perceptions of EI following their child's diagnosis with ASD; (ii) the consequences (both positive and negative) of the EI message; and (iii) parents' perspectives on life after EI. The results of this study indicated that parents were acutely aware of the importance of EI, and although this provided parents with hope immediately post-diagnosis, it also placed pressure on parental decision-making regarding which intervention approaches to access for their children with ASD.

CONCLUSIONS

The results of this study highlight the importance of carefully considering how health messages, specifically the importance of EI, are communicated to families of children with ASD. Furthermore, the findings of this study also highlight the need for allied health professionals to communicate openly with parents about the anticipated outcomes of EI programmes.

Phase I study to determine the bioavailability and tolerability of a tablet formulation of the PARP inhibitor olaparib in patients with advanced solid tumors: Dose-escalation phase

3051

Background: We previously reported the comparative bioavailability of the olaparib tablet (TAB) up to 200 mg BID, with the initial capsule formulation; gmean AUC0–T following 200 mg BID TAB was ~20% lower than 400 mg BID capsule (CAP; Molife et al ASCO 2010). Olaparib 200 mg BID TAB had an acceptable tolerability profile suggesting further dose escalation might be justified. Methods: Study NCT00777582 was amended to include a dose-escalation phase, to define the maximum tolerated dose (MTD) and safety profile of the TAB, and 2 expansion phases to compare safety and efficacy of TAB doses vs 400 mg BID CAP. Expansion phase data are reported separately. Here, we report preliminary data from the dose-escalation phase where patients (pts) with advanced solid tumors, ECOG PS 0–2 and adequate organ function were assigned to treatment with increasing olaparib BID TAB doses in 28-day continuous dosing cycles. Pharmacokinetic (PK) sampling was performed on days 1, 8, 15, 29, 57. Results: 30 pts (M:F, 3:27; median age 54 yrs [range 19–70]) were enrolled in the dose-escalation phase and received treatment at 5 dose levels: 250, 300, 350, 400 and 450 mg (each dose level, n=6). Overall, the most common AEs were nausea (80%), fatigue (73%) and diarrhea (36%). The majority of AEs were mild to moderate (CTC grade [G] 1/2). Hematologic toxicity in terms of, mostly mild, anemia, neutropenia and thrombocytopenia, appeared to increase at doses of 300 mg BID or higher. Two pts had dose-limiting toxicities at 450 mg (G3 thrombocytopenia and G3 anemia); the TAB MTD was 400 mg BID. Exposure increased proportionally with increasing dose: mean exposure after 400 mg BID was double that following the previously reported 200 mg BID dose. Following 300 and 400 mg doses, gmean Cmax ss, AUC0–T and Cmin ss matched or exceeded the 400 mg BID CAP dose. Conclusions: The MTD of olaparib TAB was 400 mg BID. Based on PK analysis, the 300 and 400 mg BID doses were selected for evaluation in the MTD expansion phase to further define safety and preliminary efficacy.

Safety and efficacy results from two randomized expansions of a phase I study of a tablet formulation of the PARP inhibitor, olaparib, in ovarian and breast cancer patients with BRCA1/2 mutations

3048

Background: We previously reported the comparative bioavailability of the capsule (CAP) formulation of olaparib and the more convenient new tablet (TAB) formulation (Molife et al ASCO 2010). We subsequently performed two separate dose expansions (DE1 and DE2) to explore comparative safety and efficacy of the TAB (NCT00777582). Methods: Patients with breast or ovarian cancer and BRCA1/2 mutations, ECOG PS 0–2 and adequate organ function were randomized to receive: DE1: 200 TAB or 400 CAP; DE2: 300 TAB, 400 TAB or 400 CAP (all mg BID). Endpoints included safety, pharmacokinetics and exploratory analysis of efficacy (change in tumor size at 8 weeks by RECIST 1.0). Groups were compared using analysis of covariance, including baseline tumor size and treatment as covariates; results are presented using least square (LS) means. Results: 24 patients (ovarian n=15, breast n=9) entered DE1 and 53 patients (ovarian n=38, breast n=15) entered DE2. Baseline characteristics including age, BRCA mutation status and tumor histology were balanced. The table shows key toxicity-related information and change in tumor size at 8 weeks by cohort. Conclusions: These data suggest a dose-response effect for tolerability and, possibly, efficacy with the new TAB between 200 and 400 mg BID. Further studies will require dosing according to patient tolerability within this dose range. [Table: see text]

Pharmacokinetic profile of the fulvestrant loading dose regimen in postmenopausal women with hormone receptor-positive advanced breast cancer

PURPOSE

Fulvestrant is at least as effective as anastrozole in the treatment of postmenopausal women with advanced breast cancer whose disease has previously progressed or recurred on antiestrogen therapy. Pharmacokinetic data have shown that, at the approved dose (250 mg/month), it takes approximately 3-6 months for fulvestrant to reach steady-state levels. Theoretically, a more rapid attainment of steady state might reduce the number of early progressions. A pharmacokinetic model simulating plasma concentrations expected to be achieved with a fulvestrant loading dose (LD) regimen suggested that steady state might be achieved earlier with the LD. The aim of this study was to characterize the pharmacokinetics of the fulvestrant LD regimen. This pharmacokinetic substudy was conducted within a phase III trial, EFECT (Evaluation of Fulvestrant versus Exemestane Clinical Trial), comparing fulvestrant with exemestane in postmenopausal women with hormone-sensitive advanced breast cancer whose disease had progressed or recurred following nonsteroidal aromatase inhibitor treatment.

PATIENTS AND METHODS

Patients received fulvestrant intramuscularly using a LD regimen of 500 mg on day 0, 250 mg on days 14 and 28, and then 250 mg each month thereafter. Blood samples were collected throughout the first month and on day 28 of each subsequent month. Plasma fulvestrant concentrations were determined by highperformance liquid chromatography-mass spectrometry, and pharmacokinetic parameters were estimated with nonlinear mixed-effects modeling.

RESULTS

Thirty-seven patients receiving fulvestrant were enrolled into the pharmacokinetic substudy, and 269 fulvestrant plasma concentrations were recorded. Maximum fulvestrant concentration (19.7 ng/mL) was observed at an average of 12 days within the first month and maintained at 12-15 ng/mL throughout the remainder of the dosing period.

CONCLUSION

Steady-state plasma levels were attained within the first month of treatment with fulvestrant LD, in line with the predictions of the pharmacokinetic model.

Alkoxy- and amidocarbonylation of functionalised aryl and heteroaryl halides catalysed by a Bedford palladacycle and dppf: a comparison with the primary Pd(ii) precursors (PhCN)2PdCl2 and Pd(OAc)2

The versatility of a Bedford-type palladacycle , namely [{Pd(micro-Cl){kappa2-P,C-P(OC6H(2)-2,4-tBu2)(OC6H(3)-2,4-tBu2)2}}2], as a primary Pd source, in combination with the ligand bis-1,1'-(diphenylphosphino)ferrocene (dppf) has been established in carbonylation reactions of aryl and heteroaryl bromides with methanol, piperidine and related nucleophiles. Palladacycle has been compared with other primary Pd sources, e.g. (PhCN)2PdCl2 and Pd(OAc)2. The efficacy of the carbonylation processes appear to be linked to the [Pd] concentration, substrate : catalyst ratio, CO pressure and reaction temperature. In amidocarbonylation, double carbonylation is observed for certain organohalides. In the case of 2,5-dibromopyridine, regioselective amination (Hartwig-Buchwald type) also occurs as a side-reaction.

Validating the Orpington Prognostic Score in an Irish in-patient stroke population

An accurate assessment of stroke severity and the ability to predict prognosis is important for determining rehabilitation needs and long term management of patients after stroke. The Orpington Prognostic Score (OPS) is a clinically derived stroke severity scale that can be used to stratify patients into different severity groups. The aim of this study was to validate the Orpington Prognostic Score (OPS) in an Irish in-patient stroke population. Fifty 'first stroke' patients (21 male, median age 72.5 [range 31-93] years) were assessed within two weeks following stroke onset. Subjects were stratified into mild, moderate and severe groups using previously established cut-offs for the OPS. Outcomes were determined prospectively and compared to initial severity groups. Patients in the severe group had a significantly increased chance of dying (Odds ratio [95%CI] 2.16 [1.72-2.72] and this persisted after adjustment for age and gender. Length of stay increased significantly with increasing stroke severity group (F ratio 7.0 p=0.0025) and this association remained after adjusting for age and gender. The odds of being discharged home or of being able to walk independently by time of discharge decreased significantly (all p<0.001) as stroke severity increased and adjusting for age and gender did not alter these associations. A higher OPS score within 2 weeks of stroke onset was significantly associated with longer length of stay, increased mortality, reduced mobility at discharge and a reduced likelihood of discharge home. The OPS is a valid measure of stroke severity in Irish stroke in-patients.

Determinants of white-coat hypertension

BACKGROUND

The prevalence of white-coat hypertension (WCH) is considerable in patients referred with elevated office blood pressure. Failure to recognise this phenomenon can lead to the inappropriate use of antihypertensive medications. We undertook this study to determine the profile of patients with WCH.

METHODS

Baseline clinic and daytime ambulatory blood pressures were available from 5716 patients referred over a 22-year period. Individuals were considered to have WCH if they had an elevated clinic blood pressure measurement greater than 140/90 mmHg and normal daytime mean ambulatory blood pressure. Mean age was 53.6 years and 53.2% were female.

RESULTS

The overall prevalence of white-coat hypertension was 15.4%. A higher prevalence was seen amongst older adults, females, and non-smokers.

CONCLUSION

Multivariate logistic regression analysis confirmed these characteristics as independent predictors of WCH.

Incidence of abnormal cerebral findings in the MRI of clinically healthy divers: role of a patent foramen ovale

BACKGROUND

To investigate incidence and number of abnormal cerebral hyperintensities (ACFs) in Magnet Resonance Imaging (MRI) and its relation to a patent foramen ovale (PFO) in divers with no history of decompression illness.

METHODS

Cohort study on 50 divers (21-5500 dives).

MAIN OUTCOME MEASURES

Incidence and number of ACFs visualized by cranial MRI and presence and size of a PFO as documented by echocardiography and transcranial Doppler ultrasound (TCD) with echocontrast.

RESULTS

A total of 137 ACFs was found in the 50 subjects, with a significant correlation between the number of dives and number of ACFs (r = 0.28; p < 0.05); but after correction for age, the remaining correlation (r = 0.15) did not reach significance. In 18 divers, a PFO was present by either the application of echocardiography or TCD; in 12 divers, the PFO was of high hemodynamic relevance. Ten of 18 divers with a PFO had at least one ACF, while in the remaining 32 divers, only 14 had at least one ACF (56% versus 44%, p = NS). Seven of 14 divers (50%) with 4 ACFs had a PFO, compared to 11 of 36 (31%) with less than 4 ACFs (p = NS).

CONCLUSION

In this cohort of healthy divers, in contrast to an earlier report, no significant association was found between PFO presence and incidence or number of ACFs.

Pharmacokinetics of midazolam in neonates undergoing extracorporeal membrane oxygenation

BACKGROUND

Although the pharmacokinetics of midazolam in critically ill children has been described, there are no such reports in extracorporeal membrane oxygenation.

METHODS

The pharmacokinetics of midazolam and 1-hydroxy midazolam after continuous infusion (50-250 microg. kg(-1). h(-1)) were determined in 20 neonates undergoing extracorporeal membrane oxygenation. Patients were randomized into two groups: group 1 (n = 10) received midazolam extracorporeally (into the circuit), and group 2 received drug via central or peripheral access. Blood samples for determination of plasma concentrations were taken at baseline, 2, 4, 6, 12, 18, and 24 h, then every 12 h. Population pharmacokinetic analysis and model building was conducted using WinNonMix (Pharsight Corporation, Mountain View, CA). The 1-hydroxy midazolam/midazolam metabolic ratio was determined as a surrogate marker of cytochrome P450 3A activity.

RESULTS

The parameter estimates (n = 19) were based on a one-compartment model with time-dependent change in volume of distribution. Volume (mean +/- standard error) expanded monoexponentially from the onset of extracorporeal membrane oxygenation to a maximum value, 0.8 l +/- 0.5 and 4.1 +/- 0.5 l/kg, respectively. Consequently, plasma half-life was substantially prolonged (median [range]) from onset to steady-state: 6.8 (2.2-39.8) and 33.3 (7.4-178) h, respectively. Total body clearance was determined as (mean +/- standard error) 1.4 +/- 0.15 ml. kg-1. min-1. The median metabolic ratio was 0.17 (0.03-0.9). No significant differences were observed between the two groups with respect to parameter estimates. Simulations of plasma concentration profiles revealed excess levels at conventional doses.

CONCLUSIONS

These results reveal significantly increased volume of distribution and plasma half-life in neonates receiving extracorporeal membrane oxygenation. Altered kinetics may reflect sequestration of midazolam by components of the extracorporeal membrane oxygenation circuit.

Prescribing practices in an Irish Long Term Care Setting

The elderly constitute 11.4% of the Irish Population and are prescribed 47% GMS prescription medications. Polypharmacy is well described in studies as being the norm and not the exception in the elderly. A long term care setting represents a particular group of these patients having medical problems that are both complex in nature and copious in number. Prescribing practices have not been well documented in the Irish Long Term Care setting. We therefore determined a need to describe prescribing patterns in the Irish Long Term Care Setting. Seventy-six patients were identified in two Long Term Care units. Data collected per patient included type of diagnosis, age, and medication prescribed. Paired data was available on 52 patients at baseline and again at six months. The impact of regular consultant review on prescribing was assessed during this period. We found that the average age of the residents was 80.9 years. Female residents accounted for 75% of the patients and males 25%. There was an average of 8.8 diagnoses per patient. At baseline there was an average of 9.2 medications prescribed per patient. The vast majority of prescriptions were for CNS preparations (42%), followed by Cardiovascular (16%) Gastrointestinal (16%) and Respiratory (6%). Medication prescribed changed in nature but numerically was not reduced by regular consultant review. The number of scheduled medications did not change over six months of review, at 5.5 per patient. However there was an increase in the number of PRN prescriptions from 3.7 to 4.25 per patient. We concluded that there is a higher than expected number of medications prescribed to patients in Long Term Care. On the basis of this descriptive study we recommend that standards be set for Prescribing in Long Term Care.

Noninvasive myocardial contractility monitoring with seismocardiography during simulated dives

OBJECTIVE

To determine if bradycardia during hyperbaric exposure is accompanied by a negative influence on myocardial contractility.

METHODS

Accelerometer-based registration of myocardial compression waves with Seismocardiography (SCG) for noninvasive contractility monitoring. Comparative pulmonary artery (PA) catheter study (9 ICU-patients, mean = 67ys) with ejection-fraction (EF) equivalent versus sum of g-values of contraction phase in SCG, and Preload (leg-positioning). Test with monitoring of changes in Contractility Index (ContrI) derived from the SCG-power spectrum (contraction phases, area under curve). Hyperbaric chamber study (0.6MPa dive-simulation) in 14 healthy divers. Quantitative SCG-(ContrI, power spectra) and ECG-recording.

RESULTS

Correlation between changes in EF (PA catheter) and in the g-values (SCG) was r(SP) = 0.87 (p < 0.0001). ContrI increased in the leg-positioning test parallel to preload increase, heart rate remained stable. During hyperbaric exposure (0.6MPa) heart rate decrease was highly significant (68 to 58 min(-1); p < 0.001), ContrI and power spectra remained nearly unchanged, SCG registration was noise free.

CONCLUSIONS

Hyperoxic bradycardia during simulated dives is not accompanied by impaired contractility measured with SCG, which is concordant to findings with invasive methods in current literature. SCG is suitable for noninvasive and stress free contractility monitoring and patient surveillance in a hyperbaric chamber.

Characterization of the immune response against hepatitis C infection in recovered, and chronically infected chimpanzees

The immune response to hepatitis C virus (HCV) is believed to be critical in determining the outcome of the disease. In this study we have analysed epitope recognition, cytokine profile, and anti-HCV antibody responses in chronically HCV-infected and recovered chimpanzees. Quantitative measurement of anti-HCV antibody in HCV-infected chimpanzees revealed that the response in HCV- recovered chimpanzees peaked within 4-20 weeks. In contrast, the anti-HCV antibody responses in chronically HCV infected chimpanzees did not peak until 100-200 weeks after infection, and decreased gradually thereafter. T cell proliferation assays measuring responses to pooled HCV proteins revealed significant increases in the 3H-uptake during the early stages of infection in recovered chimpanzees in comparison to the chronically infected ones. Class I-restricted epitopes of the core, and NS3 proteins of HCV were analysed using 9-10 mer overlapping peptides covering the core and NS3 proteins, and IFN-gamma ELISPOT technique. Our data indicated early and broad class-I restricted core, and NS3 protein epitope recognitions in HCV-recovered chimpanzees but not in chimpanzees that had been chronically infected. Additionally, dominant epitopes recognized early in infection (8 weeks) were no longer recognized later in infection (followed up to 64 weeks). Cytokines profiling revealed a 50-fold increase in TNF-alpha secretion in the supernatant of core-specific CD8 memory cells of the chronically infected chimpanzees in comparison to the recovered ones. In summary, multiple parameters correlate with HCV recovery in chimpanzees.

In vitro neuronal and vascular responses to 5-hydroxytryptamine: modulation by 4-methylthioamphetamine, 4-methylthiomethamphetamine and 3,4-methylenedioxymethamphetamine

4-Methylthioamphetamine and 4-methylthiomethamphetamine are thioarylethylamines structurally related to 3,4-methylenedioxymethamphetamine (MDMA, 'Ecstasy'). This study compared effects of these agents and MDMA on 5-hydroxytryptamine (5-HT) signalling systems in the brain and vasculature in vitro. Both 4-methylthioamphetamine and 4-methylthiomethamphetamine (100 micro M) reduced the rate of specific high affinity [3H]5-HT reuptake in isolated rat brain synaptosomes to 14% and 10% of control, respectively. The concentration required for half-maximal inhibition (IC(50)) of [3H]5-HT reuptake by 4-methylthioamphetamine (0.27 micro M) was significantly lower (P<0.005) than that for inhibition by MDMA (1.28 micro M) and that for inhibition by 4-methylthiomethamphetamine (0.89 micro M). Both 4-MTA and 4-MTMA caused a significant release of preloaded [3H]5-HT from synaptosomes, but were significantly less effective than MDMA at the concentrations tested (1-100 micro M). In isolated rat aorta, a 15-min preincubation with 4-methylthioamphetamine or 4-methylthiomethamphetamine significantly reduced the maximal contraction (E(max)) induced by 5-HT to 71% or 91% of control (P<0.05 in each case), respectively. In addition, 4-methylthiomethamphetamine (100 micro M), but not 4-methylthioamphetamine, significantly increased the concentration of 5-HT required for half-maximal contraction (EC(50)) from 4.13 to 20.08 micro M (P<0.0001). In contrast, MDMA did not significantly alter the E(max) or the EC(50) of 5-HT-induced aortic contraction. It is concluded that both 4-methylthioamphetamine and 4-methylthiomethamphetamine are potent inhibitors of [3H]5-HT reuptake in the brain. Furthermore, unlike MDMA, they both directly inhibit 5-HT-mediated vascular contraction. These results suggest that these compounds may be potentially more harmful than MDMA in the context of human misuse.

Liquid chromatography/electrospray ionisation mass spectrometric investigations of imidazoline corrosion inhibitors in crude oils

The so-called imidazolines (2-alkyl-1-[ethylalkylamide]-2-imidazolines and 2-alkyl-1-ethylamine-2-imidazolines) are a group of surface-active compounds, complex mixtures of which are used by various industries as surfactants and corrosion inhibitors. Although their industrial synthesis was reported over 100 years ago, few methods for the determination of individual imidazolines in mixtures, including industrial matrices such as crude oils, have been reported. Here we demonstrate that spiking of crude oils with synthetic imidazolines followed by solid-phase extraction and liquid chromatography/electrospray ionisation multistage mass spectrometry (LC/ESI - MS(n)) allows an estimation of low (<10) parts per million concentrations of individual imidazolines in crude oils. Whilst non-optimised at present, the method is a significant advance and may prove useful not only for improving an understanding of the mechanisms of industrial imidazoline synthesis and for monitoring downhole and topside oilfield operations, but also for the determination of the fate of imidazoline-based oilfield corrosion inhibitors and surfactants in the environment.

Analysis of oilfield produced waters and production chemicals by electrospray ionisation multi-stage mass spectrometry (ESI-MSn)

Large quantities of diverse polar organic chemicals are routinely discharged from oil production platforms in so-called produced waters. The environmental fate of many of these is unknown since few methods exist for their characterisation. Preliminary investigations into the use of multistage electrospray ionisation ion trap mass spectrometry (ESI-MSn) show its potential for the identification and quantification of compounds in specialty oilfield chemicals (corrosion inhibitors, scale inhibitors, biocides and demulsifiers) and produced waters. Multiple stage mass spectrometry (MSn) with both positive and negative ion detection allows high specificity detection and characterisation of a wide range of polar and charged molecules. For example, linear alkylbenzenesulfonates (LAS), alkyldimethylbenzylammonium compounds, 2-alkyl-1-ethylamine-2-imidazolines, 2-alkyl-1-[N-ethylalkylamide]-2-imidazolines and a di-[alkyldimethylammonium-ethyl]ether were all identified and characterised in commercial formulations and/or North Sea oilfield produced waters. The technique should allow the marine environmental effects and fates of some of these polar compounds to be studied.

[Resection of lung metastases: long-term results and prognostic analysis based on 5206 cases--the International Registry of Lung Metastases]

The International Registry of Lung Metastases was established in 1991 to asses the long-term results of pulmonary metastasectomy. The Registry has accrued 5206 cases of lung metastasectomy, from 18 departments of thoracic surgery in Europe (n = 13), USA (n = 4) and Canada (n = 1). Of these patients 4572 (88%) underwent complete surgical resection. The primary tumor was epithelial in 2260 (43%), sarcoma in 2173 (42%), germ cell in 363 (7%), and melanoma in 328 (6%) patients. The disease-free interval was 0 to 11 months in 1729 (33%) cases, 12 to 35 months in 1857 (36%) and more than 36 months in 1620 (31%). Single metastases accounted for 2383 (46%) cases and multiple lesions for 2726 (52%). Mean follow up was 46 months. Analysis was performed by Kaplan-Meier estimates of survival, relative risk of death and multivariate Cox model. The actuarial survival after complete metastasectomy was 36% at 5 years, 26% at 10 years and 22% at 15 years (median 35 months); the corresponding values for incomplete resection were 13% at 5 years and 7% at 10 years (median 15 months). Among complete resections, the 5-year survival was 33% for patients with a disease free-interval of 0 to 11 months and 45% for those with a disease-free interval of more than 36 months; 43% for single lesions and 27 for four or more lesions. Multivariate analysis showed a better prognosis for patients with germ cell tumors, disease-free interval of 36 months and more and single metastases. These results confirm that lung metastasectomy is a safe and potentially curative procedure.

Quality of life and the right to die: an ethical dilemma

In an increasingly 'patient-centred' health service individuals are demanding to make independent judgements about their own fate. In keeping with this trend there is now a growing drive to review the current laws on euthanasia and assisted suicide. The issues in the euthanasia debate usually revolve around patients who are terminally ill and/or suffering intractable pain. However, pain is not the only determinant of an intolerable existence and the problems become more complex when existential quality of life issues are the focus. This can lead to difficult decision making for the health workers involved in care. The paper uses a case study approach to examine the ethical and legal issues surrounding euthanasia. The dilemma under discussion involves a quadriplegic patient who wished to commit suicide by refusing nutrition. The discussion offered centres around the principles of beneficence, non-maleficence and autonomy in relation to whether it was morally or legally appropriate to intervene with this patient's wishes by artificial feeding. Conclusions and recommendations are offered.

Have women's voices lowered across time? A cross sectional study of Australian women's voices

Various aspects of our communication are well known to have changed over time (1-3). This article describes a cross-sectional study that examined the acoustic characteristics of two groups of Australian women aged 18-25 years from recordings made in 1945 and 1993 and investigated the possible changes in the voice across generations. Archival recordings from 1945 which had been used in a longitudinal study (4) were compared to recordings made in 1993. The results of this study show that women in 1993 have significantly deeper voices than women of the same age recorded in 1945. The possible factors influencing this change are discussed.

Passive immunization with a human immunodeficiency virus type 1-neutralizing monoclonal antibody in Hu-PBL-SCID mice: isolation of a neutralization escape variant

A monoclonal antibody (694/98-D) directed toward the V3 loop of human immunodeficiency virus type 1 (HIV-1) was evaluated for pre- and postexposure prophylaxis in SCID mice reconstituted with human peripheral blood lymphocytes (Hu-PBL-SCID). Fifty percent protection against the HIV-1LAI strain was obtained by preexposure administration of 1.32 mg/kg antibody. However, virus isolated from 1 mouse 3 weeks after passive immunization with 13.2 mg/kg antibody proved resistant to subsequent in vitro neutralization by 694/98-D. V3 loop sequence analysis of cloned virus revealed amino acid changes within the linear core epitope recognized by 694/98-D and in one flanking amino acid. Further evaluation of 694/98-D for postexposure prophylaxis in mice revealed that 694/ 98-D was effective when given 15 min after virus. However, efficacy declined to 50% if treatment was delayed to 1 h after virus inoculation. These studies point out some potential drawbacks of passive immunization with monoclonal antibodies.

Undernutrition in the elderly population living at home in the community: a review of the literature

Undernourishment in elderly people has been found to have a variety of detrimental effects ranging from the development of pressure sores to the incidence of fractured femurs. Surveys within hospital settings have revealed that elderly patients are often admitted from their homes in a state of malnutrition, which would indicate nutritional deficits in at least some of the population. Reliable nutritional assessment in the community, however, is difficult and time consuming, with findings subject to distortions from other influences. Consequently there is inadequate accurate assessment of the current nutritional status of the general elderly population, and assumptions are often based on research findings from the 1960s and 1970s. In view of the demographic changes which have moved towards an increasingly 'old' elderly population such research may no longer be relevant. This paper provides a review of the available literature on nutrition in elderly people living at home and includes possible assessment screening strategies that could be used by community nurses.

Magnetic resonance imaging of the postpneumonectomy chest: normal and abnormal findings

To determine the normal findings at magnetic resonance imaging (MRI) of the postpneumonectomy space (PPS), and to evaluate the utility of MRI in detection of recurrent tumor in the postpneumonectomy chest, 32 MRI scans were performed in 31 patients at varying time intervals after pneumonectomy. Eleven patients also had 12 computed tomography (CT) scans performed at the same time to evaluate possible tumor recurrence. Of the 32 scans, 5 demonstrated complete obliteration of the fluid containing PPS, and 4 showed gas in the PPS; the remainder (n = 23) demonstrated persistence of fluid-filled spaces of varying size. The presence of a fibrotic rim of tissue was constant. In 11 patients with clinically suspected tumor recurrences, both CT and MRI were obtained: the two modalities performed with similar accuracy in diagnosing tumor recurrence at 16 sites; CT detected opposite-lung metastatic nodules not seen on MRI in one patient, and a rib metastasis described as "indeterminate" on MRI in a second patient. MRI detected a focus of recurrence in the PPS that was indeterminate on CT. There is considerable variability in the amount of fluid seen in the PPS on MRI. CT remains the procedure of choice for routine follow-up or in suspected tumor recurrence in the postpneumonectomy patient; MRI can be helpful if the CT scan is nondiagnostic or equivocal.