Restoration of marine ecosystems: Understanding possible futures for optimal outcomes

Accelerating declines in the extent, quality and functioning of the world's marine ecosystems have generated an upsurge in focus on practical solutions, with ecosystem restoration becoming an increasingly attractive mitigation strategy for systems as diverse as coral reefs, mangroves and tidal flats. While restoration is popular because it promises positive outcomes and a return to something approaching unimpacted condition and functioning, it involves substantial public and private investment, both for the initial restoration activity and for on-going maintenance of the restored asset. This investment often affords one big chance to get things right before irretrievable damage is done. As a result, precise, well considered and accountable decision-making is needed to determine the specific focus for restoration, the scale of restoration, the location for deploying restoration activities, and indeed whether or not restoration is necessary or even possible. We explore the environmental/ecological considerations and constraints governing optimal decisions about the nature, location and prioritisation of restoration activities in marine ecosystems, and in particular the constraints on achieving understanding of possible futures and the likelihood of achieving them. We conclude that action must be informed by a context-specific understanding of the historical situation, the current situation, the constraints on change, the range of potential outcome scenarios, and the potential futures envisioned.

Characterising radium-226 particles from legacy contamination to support radiation dose assessments

Radioactive particles are physically discrete sources of radioactivity that have been released into the environment as a result of past emergencies, events and practices. As the release of radioactive particles is often unplanned, the source term has not been characterised, and the potential radiation doses have not been prospectively assessed. If a plausible exposure pathway exists, radioactive particles in the environment may present a hazard to the public depending on their radiological, physical and chemical characteristics. Given their physically discrete nature, standard assessment approaches such as dispersion and transfer modelling of liquid and gaseous radioactive releases, are not appropriate for radioactive particles. The challenge for national regulatory authorities is to calculate potential radiation doses from unplanned releases of radioactive particles into the environment, assess whether the doses are relevant to radiological protection and decide whether actions are required to reduce potential doses. To address this challenge, this paper presents the approach being adopted to radiologically, physically and chemically characterise Ra-226 particles from a contaminated legacy site using gamma spectrometry, optical macroscopy and SEM-EDS. The use of particle characterisation data to support radiation dose assessments is discussed and consideration is given to radioactive particles in the context of radiological protection.

The association between hyperandrogenemia and the metabolic syndrome in morbidly obese women

BACKGROUND

Female abdominal obesity is associated with hyperandrogenemia (HA), but few studies have addressed the possible association between HA and metabolic syndrome (MetS) among obese women. Some studies indicate that insulin resistance may cause HA through different mechanisms. On the other hand, a bidirectional relationship between HA and insulin resistance has been suggested. Thus, we aimed to investigate if morbidly obese women with HA had higher odds of MetS and its components than those without HA (controls), independent of polycystic ovarian syndrome (PCOS) status.

METHODS

This cross-sectional study comprised 1900 consecutive treatment seeking morbidly obese women <50 years. Free testosterone index (FTI) >0.6 defined HA. Women with previously diagnosed PCOS and those with oligo- / anovulation combined with clinical or biochemical hyperandrogenism were defined as having PCOS. Multiadjusted associations between HA and MetS were assessed by logistic regression analysis.

RESULTS

Out of 1900 morbidly obese women, 1089 (57 %), 846 (45 %) and 312 (16 %) had MetS, HA and PCOS, respectively. Compared with controls (without HA), women with HA were younger (34 [1] years vs. 39 [2], p < 0.001) had a higher prevalence of MetS (62 % vs. 53 %, p < 0.001), type 2 diabetes (18 % vs. 15 %, p = 0.045), low HDL-cholesterol (65 % vs. 48 %, p < 0.001) and hypertriglyceridemia (48 % vs. 41 %, p = 0.004), but a lower prevalence of raised blood pressure (53 % vs. 59 %, p = 0.014). Multivariable analyses showed that HA was associated with increased odds of MetS (OR 1.61 [95 % CI 1.27, 2.02]), dysglycemia (1.65 [1.28, 2.11]), low HDL-cholesterol (1.58 [1.27, 1.97]), and hypertriglyceridemia (1.43 [1.15, 1.79]). After stratification for the presence of PCOS, the results remained largely unchanged in women without PCOS; MetS (1.52 [1.18, 1.96), dysglycemia (1.71 [1.30, 2.25]), low HDL-cholesterol (1.55 [1.22, 1.98]) and hypertriglyceridemia (1.36 [1.06, 1.74]).

CONCLUSION

Morbidly obese women with HA had an approximately 1.5-fold increased odds of having MetS even in the absence of PCOS. Randomized controlled clinical trials, including therapeutic strategies to lower free testosterone levels, are however necessary to explore any cause-and-effect relationship.

The radium legacy: Contaminated land and the committed effective dose from the ingestion of radium contaminated materials

The manufacture and use of radium in the early to mid-20th century within industrial, medicinal and recreational products have resulted in a large number of contaminated sites across a number of countries with notable examples in the USA and Europe. These sites, represent a significant number of unregulated sources of potential radiological exposure that have collectively and hitherto not been well characterised. In 2007, the Radioactive Contaminated Land (RCL) Regulations came into force in the UK, providing the statutory guidance for regulators to classify and deal with RCL. Here we report on results derived from digestion experiments to estimate committed effective dose, a key aspect of the RCL Regulations, from the ingestion of radium contaminated sources that can be found in the environment. This case study includes particles, clinker and artefacts that arise from past military activities on a site that was once an airfield at Dalgety Bay on the Firth of Forth, UK. Since 2011 the number of radium contaminated finds has increased by one order of magnitude on the foreshore areas of Dalgety Bay. The increase in finds may in large part be attributed to a change in monitoring practice. A subsample of sixty sources was selected, on the basis of their activity and dimensions, and subjected to digestion in simulated stomach and lower intestine solutions. The study demonstrated that more radium-226 ((226)Ra) and lead-210 ((210)Pb; driven by Polonium solubility) are dissolved from sources in artificial 'stomach' solutions compared with 'lower intestine' solutions. The combined 'gut' solubility for (226)Ra and apparent (210)Pb varied from less than 1% to up to 35% ICRP 72 conversion factors were used to convert the activities measured in solution to committed effective dose. A little over 10% of the sources tested dissolved sufficient radioactivity to result in 100mSv committed effective dose to an infant. Using the solubility of 35% as a worst case, minimum source activities necessary to deliver 100mSv to the full age range of users of the foreshore were estimated. All the estimated activities have been detected and recovered through routine monitoring.

The IAEA handbook on radionuclide transfer to wildlife

An IAEA handbook presenting transfer parameter values for wildlife has recently been produced. Concentration ratios (CRwo-media) between the whole organism (fresh weight) and either soil (dry weight) or water were collated for a range of wildlife groups (classified taxonomically and by feeding strategy) in terrestrial, freshwater, marine and brackish generic ecosystems. The data have been compiled in an on line database, which will continue to be updated in the future providing the basis for subsequent revision of the Wildlife TRS values. An overview of the compilation and analysis, and discussion of the extent and limitations of the data is presented. Example comparisons of the CRwo-media values are given for polonium across all wildlife groups and ecosystems and for molluscs for all radionuclides. The CRwo-media values have also been compared with those currently used in the ERICA Tool which represented the most complete published database for wildlife transfer values prior to this work. The use of CRwo-media values is a pragmatic approach to predicting radionuclide activity concentrations in wildlife and is similar to that used for screening assessments for the human food chain. The CRwo-media values are most suitable for a screening application where there are several conservative assumptions built into the models which will, to varying extents, compensate for the variable data quality and quantity, and associated uncertainty.

Difference in mosquito species (Diptera: Culicidae) and the transmission of Ross River virus between coastline and inland areas in Brisbane, Australia

This study examined the distribution of major mosquito species and their roles in the transmission of Ross River virus (RRV) infection for coastline and inland areas in Brisbane, Australia (27 degrees 28' S, 153 degrees 2' E). We obtained data on the monthly counts of RRV cases in Brisbane between November 1998 and December 2001 by statistical local areas from the Queensland Department of Health and the monthly mosquito abundance from the Brisbane City Council. Correlation analysis was used to assess the pairwise relationships between mosquito density and the incidence of RRV disease. This study showed that the mosquito abundance of Aedes vigilax (Skuse), Culex annulirostris (Skuse), and Aedes vittiger (Skuse) were significantly associated with the monthly incidence of RRV in the coastline area, whereas Aedes vigilax, Culex annulirostris, and Aedes notoscriptus (Skuse) were significantly associated with the monthly incidence of RRV in the inland area. The results of the classification and regression tree (CART) analysis show that both occurrence and incidence of RRV were influenced by interactions between species in both coastal and inland regions. We found that there was an 89% chance for an occurrence of RRV if the abundance of Ae. vigilax was between 64 and 90 in the coastline region. There was an 80% chance for an occurrence of RRV if the density of Cx. annulirostris was between 53 and 74 in the inland area. The results of this study may have applications as a decision support tool in planning disease control of RRV and other mosquito-borne diseases.

Radioactive particles in dose assessments

Radioactive particles present a novel exposure pathway for members of the public. For typical assessments of potential doses received by members of the public, habit surveys and environmental monitoring combine to allow the assessment to occur. In these circumstances it is believed that the probability of encounter/consumption is certain. The potential detriment is assessed through sampling the use of environmental monitoring data and dose coefficients such as that in ICRP 60 [ICRP, 1990. 1990 Recommendations of the international commission on radiological protection. Publication 60. Annals of the ICRP 21 (1-3)]. However, radioactive particles often represent a hazard that is difficult to quantify and where the probability of encounter is less than certain as are the potential effects on health. Normal assessment methodologies through sampling and analysis are not appropriate for assessing the impact of radioactive particles either prospectively or retrospectively. This paper details many of the issues that should be considered when undertaking an assessment of the risk to health posed by radioactive particles.

Cost-effectiveness of omalizumab in patients with severe persistent allergic asthma

BACKGROUND

The health, economic and societal burden of asthma is considerable, and is greatest in patients with severe asthma, particularly when inadequately controlled. Real-life studies that assess the effectiveness of treatment are of particular interest.

METHODS

We determined the incremental cost-effectiveness ratio (ICER) of adding omalizumab to standard therapy using data from the real-life 1-year randomized open-label study (ETOPA) and using Canada as a reference country. Only patients receiving high-dose ICS plus LABA were included in the analysis, reflecting the EU label for omalizumab. Costs and quality-adjusted life years (QALYs) gained were used to calculate the ICER for omalizumab (cost/QALY). Probabilistic sensitivity analysis was performed to determine the 95% confidence interval and one-sided sensitivity analyses were performed.

RESULTS

The base case lifetime analysis of standard therapy vs standard therapy plus add-on omalizumab for the first 5 years, gave an ICER of 31,209 Euro. Probabilistic sensitivity analysis indicated that the 95% confidence interval around the ICER was 27,739-40,840 Euro. The ICER range for one-way sensitivity analyses was 23,762 Euro without discounting to 66,443 Euro without inclusion of asthma-related mortality.

CONCLUSIONS

This study demonstrates that add-on omalizumab therapy is cost-effective in patients with severe persistent allergic asthma.

Shwachman-Diamond syndrome: UK perspective

So much has been added to our knowledge of Shwachman-Diamond syndrome (SDS) since it was last reviewed in this journal some 25 years ago, that there is now an urgent need to bring the condition to the attention of a new generation of paediatricians. SDS, although a rare autosomal recessive disorder, demands wide attention because it features in the differential diagnosis of a number of important childhood diseases. It can be diagnosed in children of all ages, or in adults. SDS most commonly presents in infancy with features of exocrine pancreatic insufficiency, bone marrow dysfunction, and short stature.

Climatic, high tide and vector variables and the transmission of Ross River virus

This report assesses the impact of the variability in environmental and vector factors on the transmission of Ross River virus (RRV) in Brisbane, Australia. Poisson time series regression analyses were conducted using monthly data on the counts of RRV cases, climate variables (Southern Oscillation Index and rainfall), high tides and mosquito density for the period of 1998-2001. The results indicate that increases in the high tide (relative risk (RR): 1.65; 95% confidence interval (CI): 1.20-2.26), rainfall (RR: 1.45; 95% CI: 1.21-1.73), mosquito density (RR: 1.17; 95% CI: 1.09-1.27), the density of Culex annulirostris (RR: 1.25; 95% CI: 1.13-1.37) and the density of Ochlerotatus vigilax (RR: 2.39; 95% CI: 2.30-2.48), each at a lag of 1 month, were statistically significantly associated with the rise of monthly RRV incidence. The results of the present study might facilitate the development of early warning systems for reducing the incidence of this wide-spread disease in Australia and other Pacific island nations.

An assessment of mosquito breeding and control in four surface flow wetlands in tropical-subtropical Australia

In Queensland, Australia, the tropical-subtropical climate is ideal to promote macrophyte growth in surface flow wetlands; however, there have been concerns that constructed wetlands are potential breeding sites for disease-bearing mosquitoes. The aim of this study was to assess whether mosquitoes were breeding in these constructed wetlands, and if so, where they breed, and what parameters might influence breeding: e.g. water quality, vegetation, or macroinvertebrate communities. A study of four surface flow constructed wetlands located in different climatic regions was undertaken. Mosquito larvae were sampled using 240 ml dippers and macroinvertebrates using dip nets. The wetland with the greatest biodiversity of macrophytes and macroinvertebrates had the least number of mosquito larvae (< 1% of all dips). Samples with most mosquito larvae occurred amongst dense mats of Paspalum grass or dead Typha. Despite the presence of larvae in some parts of these wetlands very few late instars or pupae were found i.e. completion of the mosquito life cycle to adult mosquitoes was unsuccessful. This study has shown that the presence of mosquito larvae can be minimised by increasing macroinvertebrate biodiversity, by planting a variety of macrophyte types and species, excluding aggressive plant species, and maintaining at least 30% open water. Macroinvertebrates are probably a crucial factor in the control of mosquito larvae ensuring that predation of the early instars prevents or limits the development of pupae and the emergence of adults.

Measuring variability in early child language: don't shoot the messenger

Feldman et al. criticize the MacArthur Communicative Development Inventories (CDIs) as having too much variability, too little stability, and insufficient ability to predict early language delay. We present data showing that these characteristics of the CDI are authentic reflections of individual differences in early language development rather than measurement deficiencies. We also respond to their critical assertions concerning sociodemographic influences on the CDI scores.

Pararetrovirus-crucifer interactions: attack and defence or modus vivendi?

Abstract The compatible infection of plants by viruses usually leads to the development of systemic symptoms. Symptom expression of this kind is generally understood to be a host response that indicates an inability of the host to defend itself from attack. We have been studying compatible interactions between the plant pararetrovirus cauliflower mosaic virus (CaMV) and its crucifer hosts in order to understand the relationship between viral activity, symptom expression and plant defence. A CaMV protein (P6) appears to play a major role in eliciting symptom expression. This host response leads to a regulation of the viral multiplication cycle that is associated with leaf mosaics. The host regulation of CaMV appears to operate at the transcriptional level through an effect on the 35S promoter, or at the post-transcriptional level by a process that is akin to gene silencing, and can lead to host recovery depending upon the genetic background of the host. The plant apex is a focus for antiviral defence mechanisms, presumably because viral infection of the apical meristem would rapidly compromise the ability of the plant to generate new leaves and flowers for reproduction. The balance of interactions between CaMV and crucifers can provide a sustainable source of host plants to ensure viral propagation and viral exposure allows the host to adapt and develop its repertoire of defence mechanisms.

Genetic epidemiological study of schizophrenia in Palau, Micronesia: prevalence and familiality

We are studying the genetic etiology of schizophrenia in the Republic of Palau, a remote island nation in Micronesia that has been geographically and ethnically isolated for approximately 2,000 years. The first epidemiological phase sought to estimate the lifetime prevalence of schizophrenia and evaluate the familiality of the illness based on complete ascertainment of cases and families segregating schizophrenia. A total of 160 strictly defined cases of schizophrenia were ascertained in a population of 13,750 adults who were 15 years of age and older. The lifetime prevalence of strictly defined schizophrenia in Palau was 1.99% overall and 2.77% in males vs. 1.24% in females. This greater than 2:1 male-to-female risk ratio for schizophrenia was accompanied by an earlier mean age of onset for males (23.3 years) than for females (27.5 years). These 160 cases of strict schizophrenia represent 59 separate families each identified by a single common founder. Eleven of these families have 5 to 14 cases and represent nearly half of the strict schizophrenia cases in Palau. Although schizophrenia is clearly aggregating in these 11 families, cases are distributed sparsely throughout the large sibships. In the entire sample of 160 cases of strict schizophrenia, there were only 11 sib-pairs and 2 sib-trios. When a family was defined to include third-degree relatives, only 11 cases (6.9%) were nonfamilial. The majority of the ascertained cases can be linked together into extended pedigrees with complex multilineal inheritance patterns. These intricately interconnected families may pose challenges for traditional linkage techniques. However, these Palauan families represent a valuable resource for studying the genetic etiology of schizophrenia because there may be fewer susceptibility genes for schizophrenia in this genetic isolate than in the heterogeneous populations that are common throughout the world today.

Evidence for a chromosome 2p13-14 schizophrenia susceptibility locus in families from Palau, Micronesia

A large multiplex schizophrenia pedigree ascertained from the Micronesian nation of Palau was genotyped with 406 microsatellite DNA markers evenly distributed throughout the genome. Assuming autosomal dominant inheritance, the highest genome-wide lod scores were found for DNA loci mapping to 2p13-14; the maximum lod score was 2.17 (theta = 0.05) at D2S441. A nonparametric APM analysis was also suggestive at D2S441 (APM score = 2.96, P = 0.011). Of the 14 affected cases in this extended family, eight share a large haplotype in this region spanning approximately 11 cM. When 16 other families containing 65 schizophrenic cases were typed in a follow-up study of this region, the maximum lod score remained positive (maximum at D2S441 1.69, theta = 0.20). APM results also remained positive at D2S441 for all 17 families (APM score = 4.87, P = 0.0006). The linkage and haplotype sharing results provide suggestive evidence for a 2p locus predisposing to schizophrenia in a subset of families in the Palauan population.

On memories of childhood abuse: a phenomenological study

OBJECTIVE

To explore the phenomenon of memories and reported recovered memories of childhood abuse, and to examine ways in which clients and therapists assess the veridicality of such memories.

METHOD

Qualitative methodology utilizing phenomenological inquiry. Within the context of a wider study exploring perceptions of helpful and unhelpful factors in the therapeutic process, a sub-sample of 36 in-depth interviews with clients, therapists, and therapists who considered themselves to have been abused as children included a focus on abuse-memory experiences. Data were analyzed according to Grounded Theory principles.

RESULTS

Participants described six types of abuse-memory experiences. The most frequently reported type was where abuse was known about but kept "out of mind." The six types can be collapsed into three main categories: (1) continual knowledge of abuse (69.5%); (2) unexpected abuse-memories recovered from a prior state of partial knowledge of abuse (16.5%); and (3) abuse-memories recovered from a prior state of no knowledge of abuse (30%). Independent corroboration of recovered memories was rare; and criteria which were reportedly used to assess the veridicality of such memories were problematic when viewed in the light of cognitive psychology research on memory processes.

CONCLUSION

It seems that most people who were abused as children have always had continual knowledge of this, although it is often only much later than many connect problems in adult life with the consequences of such abuse. People also experience the recovery of memories of abuse about which they were previously unaware. There is a danger that the specific controversy surrounding "false memories" may become over-generalized contributing to increased public scepticism about the prevalence and negative impact of child abuse, and the potential effectiveness of appropriate therapeutic services.

The inhibition of radiation-induced mutagenesis by the combined effects of selenium and the aminothiol WR-1065

In order to evaluate the anti-mutagenic effects of the potential chemoprotective compounds selenium and (S)-2-(3-aminopropylamino)ethylphosphorothioic acid (WR-1065), CHO AA8 cells were exposed to both compounds either individually or in combination prior to irradiation. Mutation frequency following exposure to 8 Gy was evaluated by quantitation of the mutations detected at the hprt locus of these cells. Protection against radiation-induced mutation was observed for both 30 nM sodium selenite or 4 mM WR-1065. In addition, the protection against mutation induction provided by the combination of these agents appeared additive. In contrast, sodium selenite did not provide protection against radiation toxicity when provided either alone or in conjunction with WR-1065. In order to evaluate the possible mechanisms of the anti-mutagenic effects observed in these cells, glutathione peroxidase (GPx) activity was evaluated following exposure to the chemopreventative compounds. The addition of sodium selenite to the culture media resulted in a 5-fold increase in GPx activity, which was unaltered by the presence of the WR-1065. Northern analysis of RNA derived from these cells indicated that selenium supplementation resulted in a marginal increase in the mRNA for the cytosolic GPx (GSHPx-1) which was insufficient to account for the stimulation of GPx activity observed in cellular extracts. These results suggest that selenium and WR-1065 offer protection via independent mechanisms and that GPx stimulation remains a possible mechanism of the anti-mutagenic effect of selenium.

Factors influencing the emigration of physicians from Canada to the United States

OBJECTIVE

To determine whether location of postgraduate medical training and other factors are associated with the emigration of physicians from Canada to the United States.

DESIGN

Case-control study, physicians were surveyed with the use of a questionnaire mailed in May 1994 (with a reminder sent in September 1994), responses to which were accepted until Dec. 31, 1994.

PARTICIPANTS

Physicians randomly selected from the CMA database, 4000 with addresses in Canada and 4000 with current addresses in the United States and previous addresses in Canada.

OUTCOME MEASURES

Sex, age, location of undergraduate and postgraduate medical training, qualifications, practice location, opinions concerning residence decisions, current satisfaction and plans.

RESULTS

The overall response rate was 49.6% (50.0% among physicians in the United States and 49.2% among those in Canada). Age and sex distributions were similar among the 8000 questionnaire recipients and the nearly 4000 respondents. Physicians living in the United States were more likely to be older (mean 53.2 v. 49.6 years of age), male (87% v. 75%) and specialists (79% v. 52%) than those practising in Canada. Postgraduate training in the United States was associated with subsequent emigration (odds ratio 9.2, 95% confidence interval 7.8 to 10.7). However, in rating the importance of nine factors in the decision to emigrate or remain in Canada, there was no significant difference between the two groups in the rating assigned to location of postgraduate training. Professional factors rated most important by most physicians in both groups were professional/clinical autonomy, availability of medical facilities and job availability. Remuneration was considered an equally important factor by those in Canada and in the United States. Six of seven personal/family factors were rated as more important to their choice of practice location by respondents in Canada than by those in the United States. Current satisfaction was significantly higher among respondents in the United States. Most physicians in each group planned to continue practising at their current location. Of Canadian respondents, 22% indicated that they were more likely to move to the United States than they were a year beforehand, whereas 4% of US respondents indicated that they were more likely to return to Canada.

CONCLUSIONS

Factors affecting the decision to move to the United States or remain in Canada can be categorized as "push" factors (e.g., government involvement) and "pull" factors (e.g., better geographic climate in the US). Factors can also be categorized by whether they are amenable to change (e.g., availability of medical facilities) or cannot be managed (e.g., proximity of relatives). An understanding of the reasons why physicians immigrate to the United States or remain in Canada is essential to planning physician resources nationally.

Thiol and disulfide metabolites of the radiation protector and potential chemopreventive agent WR-2721 are linked to both its anti-cytotoxic and anti-mutagenic mechanisms of action

The ability of the potential chemopreventive agent S-2-(3-aminopropylamino)ethylphosphorothioic acid (WR-2721) to protect against radiation-induced mutagenesis at the hprt locus and cell killing was studied using CHO-AA8 cells incubated for 30 min at 37 degrees C in growth medium containing its active thiol 2-[(aminopropyl)amino]ethane-thiol (WR-1065). In parallel experiments, the thiol and disulfide forms of the drug present in cells and incubation medium were determined in order to identify which, if either, of the components were associated with the observed protective effects. Treatment with 4 mM WR-1065 produced significant intracellular levels of the thiol (WRSH) and disulfide (WRSS) forms of the drug, but also caused dramatic elevation of cellular glutathione (GSH) and cysteine levels, accompanied by marked protection against 60Co gamma-photon- and neutron-induced cell killing and mutagenesis. When drug-treated cells were transferred to drug-free medium and incubated for 4 h at 37 degrees C, levels of WRSH and WRSS and protection against cell killing decreased markedly, whereas levels of GSH and cysteine and protection against mutagenesis showed little change. GSH and cysteine levels were not associated with protection against radiation-induced mutagenesis, as established by experiments performed with buthionine sulfoximine to block GSH synthesis. These data do not support the hypothesis that modulation of GSH or cysteine levels by WR-1065 is a major mechanism accounting for protection. Protection against mutagenesis was seen for cells incubated in medium with concentrations of added WR-1065 as low as 10 microM, where cellular levels of WRSH and WRSS became difficult to measure (< or = 5 microM) and no protection against cell killing was found. An unexpected observation was that cells incubated in 40 microM WR-1065 incorporated the drug much more rapidly than expected for uptake by passive diffusion and concentrated the drug to a marked degree; this indicates that a cell-mediated transport system is involved in the uptake of WR-1065 at low drug concentrations.

Does the number of trainees in a postgraduate training program influence the pass rates on certifying examinations?

We tested the hypothesis that small training programs (3 or fewer residents) lack the "critical mass" needed for an optimal learning experience, and thus graduates of small programs will have a lower pass rate on the Royal College of Physicians and Surgeons of Canada (RCPSC) certifying exams that graduates of large (10 or more residents) training programs. Pass rates on the RCPSC certifying exams (written and oral) were compared to the training program size for each of 6 years from 1984/85 to 1989/90 within 10 of the 43 RCPSC (sub)specialties selected by meeting predefined program size requirements. These 10 specialties met the size variation requirements needed to test the hypothesis: neurology, cardiology, emergency medicine, community medicine, neurosurgery, urology, plastic surgery, dermatology, anatomical pathology, and respiratory medicine. Of these, 3 specialties had a significantly lower written exam pass rate for candidates trained in small compared to large programs. The same 3 specialties (neurology, neurosurgery, and community medicine) had a higher proportion of International Medical Graduates (IMGs) in small training programs. The significantly lower pass rate of IMGs, compared to Canadian/USA graduates, accounted for a portion of the correlation of small program size with lower pass rates in these 3 specialties. By pooling the results from the 10 specialties evaluated, candidates from small (3 or fewer residents) training programs have slightly lower pass rates (11%) on written certification examinations compared to candidates from large (10 or more residents) training programs. This small but statistically significant effect on the pooled results was due to averaging of a more marked program size effect from 3 of the 10 specialties.(ABSTRACT TRUNCATED AT 250 WORDS)

Evaluation of a clinical score for prognostic stratification of elderly stroke patients

Orpington Prognostic Score (OPS) is a clinically derived score which incorporates measures of motor deficit, proprioception, balance and cognition. OPS and urinary continence were measured prospectively in 217 stroke survivors over 75 years of age at 1, 2 and 4 weeks after stroke and were correlated with dependence at discharge. Three levels of dependence were defined based on personal self-care abilities. OPS ranged from 2.0 to 3.2 (median 2.8) at 2 weeks after stroke in patients independent at discharge (n = 54). Their initial median Barthel index of 4 improved by a median of 12. Urinary continence was achieved in 95% of these patients by 2 weeks. All patients were discharged home, 39 (72%) within 4 weeks. Patients with limited dependence at discharge (n = 129) had OPS of 3.2-4.8 (median 4.0) at 2 weeks. Two-thirds were continent at 2 weeks. Their initial median Barthel index was 2 and changed by a median of 12. Seventy-one (55%) of these patients went home. OPS ranged from 5.2 to 6.8 (median 6.0) at 2 weeks in patients dependent at discharge (n = 34). About 20% of these patients were continent. Their initial median Barthel index of 2 improved by a median of 6 at discharge. Only five (15%) patients in this group went home. OPS was comparable with urinary incontinence for sensitivity (96% vs. 90%), specificity (36% vs. 39%) and accuracy (75% vs. 66%) in identifying stroke patients achieving independent living. OPS had a greater predictive value than urinary incontinence in identifying patients requiring institutional care (82% vs. 57%). OPS is a simple objective predictor of outcome in elderly stroke patients, suitable for everyday clinical use. It also can facilitate stroke research by identifying a 'middle group' of patients who would be most sensitive to changes in therapy or organization of stroke services.

The effects of Arthritis Society fellowships on career choice

OBJECTIVE

To find out if The Arthritis Society (TAS) fellowship grants influenced career choice or career development.

METHODS

Two hundred former TAS training fellowship recipients (1975-1990 inclusive) were sent a questionnaire to evaluate the effects of TAS clinical or research fellowship support on their subsequent career development.

RESULTS

One hundred and forty (70%) completed questionnaires were returned by 88 clinical and 37 research fellowship recipients--a further 17 had received both a clinical and a research fellowship. Fifty-one percent of the respondents are now academic rheumatologists, 40% in community practice and 9% still in training. Seventy-three percent of the research fellowship recipients currently receive research grant support, compared to 16% of the former clinical fellowship recipients. Seventy-one percent agreed that their TAS fellowship support had "directly or indirectly influenced or facilitated their chosen career path"--this included 100% of the research fellowship recipients, compared to 55% of the clinical fellowship recipients. The majority decided on an academic or a community based career path during their postgraduate training. Fourteen percent who trained for an academic career are now in community practice and 9% who planned on a community based career later became academic rheumatologists. Eighty-nine respondents (64%) enclosed a CV. This subset was further analyzed using career markers such as academic rank, number and size of research grants and number of publications. In this subset those who had received both a clinical and a research fellowship had the most advanced academic rank (22% full professor), largest number of publications (n = 39) and largest number of grants (5.3/year; average $40,446), compared to former research fellowship recipients: 4.0% full professor, 22 publications, 3.2 grants/year; average $25,164. Recipients of clinical fellowships in this subset had lower levels of all the academic career markers.

CONCLUSION

Of 200 consecutive TAS fellowship recipients 71% of those responding (n = 140) to a career tracking study agreed that the fellowship support "directly or indirectly" influenced or facilitated their career choice. An apparent synergistic effect of providing both clinical and research fellowships on subsequent development of an academic career deserves further study.

Developmental and stylistic variation in the composition of early vocabulary

Results are reported for stylistic and developmental aspects of vocabulary composition for 1,803 children and families who participated in the tri-city norming of a new parental report instrument, the MacArthur Communicative Development Inventories. We replicate previous studies with small samples showing extensive variation in use of common nouns between age 0; 8 and 1;4 (i.e. 'referential style'), and in the proportion of vocabulary made up of closed-class words between 1;4 and 2;6 (i.e. 'analytic' vs. 'holistic' style). However, both style dimensions are confounded with developmental changes in the composition of the lexicon, including three 'waves' of reorganization: (I) an initial increase in percentage of common nouns from 0 to 100 words, followed by a proportional decrease; (2) a slow linear increase in verbs and other predicates, with the greatest gains taking place between 100 and 400 words; (3) no proportional development at all in the use of closed-class vocabulary between 0 and 400 words, followed by a sharp increase from 400 to 680 words. When developmental changes in noun use are controlled, referential-style measures do not show the association with developmental precocity reported in previous studies, although these scores are related to maternal education. By contrast, when developmental changes in grammatical function word use are controlled, high closed-class scores are associated with a slower rate of development. We suggest that younger children may have less perceptual acuity and/or shorter memory spans than older children with the same vocabulary size. As a result, the younger children may ignore unstressed function words until a later point in development while the older children tend to reproduce perceptual details that they do not yet understand. Longitudinal data show that early use of function words (under 400 words) is not related to grammatical levels after the 400-word point, confirming our 'stylistic' interpretation of early closed-class usage. We close with recommendations for the unconfounding of stylistic and developmental variance in research on individual differences in language development, and provide look-up tables that will permit other investigators to pull these aspects apart.

Adverse effects of low dose methotrexate therapy in rheumatoid arthritis

OBJECTIVE

To determine (1) the risk of treatment termination for low dose, weekly methotrexate (MTX) therapy in patients with rheumatoid arthritis (RA), and (2) the prevalence, nature and predictors of adverse effects due to longterm low dose MTX therapy.

METHODS

A 13-year, retrospective survey of all patients with RA receiving low dose MTX therapy was conducted using life table, logistic regression and case control methods of analyses. Major and minor adverse effects were defined.

RESULTS

Consecutive patients with RA (144) starting MTX (mean dose 8.2 mg/week) were observed to have a 75% risk of treatment termination at 60 months. Reasons for 81 patients stopping MTX were adverse effects (43), loss/lack of effect (18), other medical and nonmedical reasons (13), and lost to followup (7). Sixty-two patients experienced 83 major adverse events, including gastrointestinal symptoms (29), hepatic enzyme test abnormalities (23), pneumonitis (5) and severe leukopenia (8). Aging was the only predictor of treatment discontinuation associated with a major toxicity. Five patients developed a malignancy during the observation period.

CONCLUSIONS

In our survey the risk of treatment termination was 75% in patients with RA taking MTX after 60 months. An adverse drug effect is a more common reason for treatment termination (53%), compared to loss/lack of beneficial effect (22%) or other reasons (16%) or lost to followup (9%). Increasing age is associated with an increased risk of treatment termination associated with a major toxicity.

Improving stroke rehabilitation. A controlled study

BACKGROUND AND PURPOSE

Assessment of stroke rehabilitation is complicated by the heterogeneity of patients and settings and by difficulties in disentangling effects of organization from effects of types and amounts of treatment input.

METHODS

A prospective controlled study was undertaken in 245 stroke patients stratified into three groups according to prognosis and managed on a stroke rehabilitation unit (n = 124) or general medical wards (n = 121). Patients were randomly allocated to either setting 2 weeks after stroke and were comparable for baseline characteristics.

RESULTS

Patients on general medical wards received more physiotherapy on average (16.2 +/- 7.2 versus 14.3 +/- 3.2 hours; P < .05) but similar amounts of occupational therapy (9.3 +/- 2.8 versus 9.5 +/- 3.2 hours) compared with stroke unit patients. More time was spent on individual rehabilitation on the stroke unit compared with general wards (P < .001). Functional abilities at discharge, destination of discharge, and length of hospital stay in patients with good prognosis were comparable in both settings. Patients with poor prognosis managed on general wards showed higher mortality (P < .05) and longer hospital stay (123.2 +/- 48.2 versus 52.3 +/- 19.8 days; P < .001), but functional abilities at discharge in survivors were comparable with those of stroke unit patients. Patients with intermediate prognosis had significantly better outcome on the stroke unit, with more patients being discharged home (75% versus 52%; P < .001), shorter average length of hospital stay (48.7 +/- 17.2 versus 104.6 +/- 28.6 days; P < .001), and better functional abilities at discharge (P < .05).

CONCLUSIONS

Stroke units improve outcome and reduce hospital stay without increasing therapy time. Their effectiveness may be enhanced by patient selection.

Analysis of a desiccation and ABA-responsive promoter isolated from the resurrection plant Craterostigma plantagineum

The resurrection plant Craterostigma plantagineum can recover from severe desiccation within 24 h of contact with water, and it is used as a model system to analyse desiccation tolerance in higher plants. During drying or ABA treatment a specific set of transcripts accumulates rapidly in leaves and other tissues. In order to study transcriptional mechanisms of stress-induced gene expression one gene (CDeT27-45) was selected for promoter analysis. Chimeric gene fusions were constructed of the CDeT27-45 promoter and beta-glucuronidase or luciferase. These constructs were tested in a homologous transient expression system which allowed the identification of promoter elements conferring ABA inducibility. By introducing the chimeric gene fusions into tobacco via Agrobacterium-mediated transformation we found that the promoter activity is under strict tissue-specific and developmental control. In tobacco the promoter was only active in developing embryos and in mature pollen grains-two tissues which are naturally desiccation tolerant in tobacco. The specific temporal expression pattern was attributed to particular 5' upstream sequences. The promoter analysis presented here should allow the separation of important regulatory components as a first step in dissecting events in the signal transduction chain.

Pancytopenia associated with low dose methotrexate therapy. A regional survey

OBJECTIVE

To determine which risk factors are associated with serious pancytopenia associated with low dose methotrexate (MTX) therapy.

METHODS

All Ottawa area rheumatologists, hematologists and dermatologists were surveyed to obtain cases of pancytopenia associated with low dose MTX therapy between 1981 and 1991. Pancytopenia was defined as white blood cells < 3.5 x 10(9)/l and platelets < 140 x 10(9)/l and hemoglobin < 100 g/l. A case control method was used to evaluate risk factors.

RESULTS

Fifteen cases of pancytopenia were identified from returned questionnaires (93% response rate) and from reviewing the medical records of 2 major teaching hospitals. All patients were hospitalized, had MTX therapy discontinued and were treated: 12 patients received transfusions, 8 leucovorin therapy, and 4 folic acid. Two patients died, only 1 directly due to MTX therapy. Identified risk factors were (1) elevated BUN or creatinine levels, (2) increasing mean corpuscular volume values, (3) increased age and (4) concomitant trimethoprim-sulfamethoxazole therapy.

CONCLUSIONS

Pancytopenia associated with low dose MTX therapy is a life threatening adverse effect often associated with known risk factors. A change in monitoring guidelines and patient education are suggested as means of risk reduction.

Benign breast disease in systemic sclerosis (SSc). A case-control study

We hypothesized that Systemic Sclerosis (SSc) may affect the breast in the form of Benign Breast Disease (BBD). For the purpose of this study BBD was defined as breast symptoms either detected by the patient resulting in physician consultation, or detected by a physician during the course of a routine consultation, or detected by a physician during the course of a routine physical exam. Forty-one of 47 women with SSc were matched to case controls from two disease groups (RA and OA). Case matching was done for age (+/- 5 years), disease duration (+/- 3 years) and gender. A structured telephone interview was administered to all subjects and controls to determine the frequency of BBD and associated risk factors. The SSc group had a higher prevalence of BBD compared to the RA group (12/41 versus 4/41, p less than 0.04). However, a similar proportion of the SSc patients and OA case controls had BBD (7/28 versus 9/28). These differences could not be attributed to any of the evaluated risk factors. The RA group had a higher frequency and longer duration of NSAID use, suggesting that the increased use of NSAIDs in the RA patients may account for the lower prevalence of BBD, although genetic, hormonal or undetermined factors may be operative. Without an age-matched, "healthy" general population control group it is impossible to determine if the observed difference in prevalence of BBD represents a less than normal prevalence in RA or a greater than normal prevalence in SSc and OA.

Protection against AZT-induced mutagenesis at the HGPRT locus in a human cell line by WR-151326

The anti-AIDS agent, AZT (3'-azido-3'-deoxythymidine), is mutagenic in a cultured human hepatoma cell line designated HepG2 at the HGPRT (hypoxanthine-guanine phosphoribosyl transferase) locus. Using an exposure time of 3 hr, the number of mutants per 10(6) surviving cells increased as a function of AZT dose from 125 to 520. Chinese hamster ovary cells, in contrast, are not affected with respect to this endpoint when similar concentrations of AZT are used (i.e., 0.1 to 10 mg/ml). The aminothiol WR-151326 [3-(3-methylaminopropylamino) propanethiol dihydrochloride] was evaluated as a possible antimutagen for use with AZT. At a concentration of 4 mM, WR-151326 was added either concomitantly or following exposure of HepG2 cells to a 5 mg/ml concentration of AZT. Regardless of the treatment condition, WR-151326 was effective in reducing the mutagenic effects of AZT by about a factor of 2. Correcting for background mutations, the mutation frequencies determined were: AZT only for 3 hr, 110 x 10(-6) (S.E.M. +/- 6.0 x 10(-6)); AZT together with WR-151326 for 3 hr, 57 x 10(-6) (S.E.M. +/- 3.0 x 10(-6)); and AZT for 3 hr followed by WR-151326 for 3 hr, 68 x 10(-6) (S.E.M. +/- 5.0 x 10(-6)). This study demonstrates that AZT is mutagenic to a cell line of human origin and that WR-151326 can protect against this mutagenic process.

In vitro vs in vivo corrosion analyses of two alloys

The in vitro and in vivo corrosion characteristics of two alloys, cast Co-Cr-Mo (ASTM F75) and wrought Ni-Cr-Mo, were evaluated using electro-chemical corrosion analysis. Two in vitro electrolytic solutions were utilized, an isotonic saline solution consisting of 0.9 w/o NaCl in distilled water and an isotonic saline solution with 10 v/o sterile calf serum. The in vivo environment was created by implanting cylindrically shaped specimens of each alloy into the back muscles of New Zealand white rabbits. Cyclic anodic and cathodic polarization curves were generated for the three test conditions and subsequently were compared. Anodic curves conducted using the isotonic saline and isotonic saline plus serum electrolyte solutions were very similar to the anodic curves generated for the implanted alloy specimens for both alloys. The corrosion rates predicted from the in vitro and in vivo cathodic polarization curves were not statistically different for the three test conditions. Overall, the corrosion data generated using the in vitro environmental conditions adequately predicted the in vivo corrosion behavior of the cast Co-Cr-Mo and wrought Ni-Cr-Mo alloys.