Signal transduction at GPCRs: Allosteric activation of the ERK MAPK by β-arrestin

β-arrestins are multivalent adaptor proteins that bind active phosphorylated G protein-coupled receptors (GPCRs) to inhibit G protein signaling, mediate receptor internalization, and initiate alternative signaling events. β-arrestins link agonist-stimulated GPCRs to downstream signaling partners, such as the c-Raf-MEK1-ERK1/2 cascade leading to ERK1/2 activation. β-arrestins have been thought to transduce signals solely via passive scaffolding by facilitating the assembly of multiprotein signaling complexes. Recently, however, β-arrestin 1 and 2 were shown to activate two downstream signaling effectors, c-Src and c-Raf, allosterically. Over the last two decades, ERK1/2 have been the most intensely studied signaling proteins scaffolded by β-arrestins. Here, we demonstrate that β-arrestins play an active role in allosterically modulating ERK kinase activity in vitro and within intact cells. Specifically, we show that β-arrestins and their GPCR-mediated active states allosterically enhance ERK2 autophosphorylation and phosphorylation of a downstream ERK2 substrate, and we elucidate the mechanism by which β-arrestins do so. Furthermore, we find that allosteric stimulation of dually phosphorylated ERK2 by active-state β-arrestin 2 is more robust than by active-state β-arrestin 1, highlighting differential capacities of β-arrestin isoforms to regulate effector signaling pathways downstream of GPCRs. In summary, our study provides strong evidence for a new paradigm in which β-arrestins function as active "catalytic" scaffolds to allosterically unlock the enzymatic activity of signaling components downstream of GPCR activation.

Pan-Asian adapted ESMO Clinical Practice Guidelines for the diagnosis, treatment and follow-up of patients with metastatic colorectal cancer

The European Society for Medical Oncology (ESMO) Clinical Practice Guidelines for the diagnosis, treatment and follow-up of patients with metastatic colorectal cancer (mCRC), published in late 2022, were adapted in December 2022, according to previously established standard methodology, to produce the Pan-Asian adapted (PAGA) ESMO consensus guidelines for the management of Asian patients with mCRC. The adapted guidelines presented in this manuscript represent the consensus opinions reached by a panel of Asian experts in the treatment of patients with mCRC representing the oncological societies of China (CSCO), Indonesia (ISHMO), India (ISMPO), Japan (JSMO), Korea (KSMO), Malaysia (MOS), the Philippines (PSMO), Singapore (SSO), Taiwan (TOS) and Thailand (TSCO), co-ordinated by ESMO and the Japanese Society of Medical Oncology (JSMO). The voting was based on scientific evidence and was independent of the current treatment practices, drug access restrictions and reimbursement decisions in the different Asian countries. The latter are discussed separately in the manuscript. The aim is to provide guidance for the optimisation and harmonisation of the management of patients with mCRC across the different countries of Asia, drawing on the evidence provided by both Western and Asian trials, whilst respecting the differences in screening practices, molecular profiling and age and stage at presentation, coupled with a disparity in the drug approvals and reimbursement strategies, between the different countries.

Pan-Asian adapted ESMO Clinical Practice Guidelines for the diagnosis treatment and follow-up of patients with localised colon cancer

The most recent version of the European Society for Medical Oncology (ESMO) Clinical Practice Guidelines for the diagnosis, treatment and follow-up of localised colon cancer was published in 2020. It was decided by both the ESMO and the Japanese Society of Medical Oncology (JSMO) to convene a special virtual guidelines meeting in March 2021 to adapt the ESMO 2020 guidelines to take into account the ethnic differences associated with the treatment of localised colon cancer in Asian patients. These guidelines represent the consensus opinions reached by experts in the treatment of patients with localised colon cancer representing the oncological societies of Japan (JSMO), China (CSCO), India (ISMPO), Korea (KSMO), Malaysia (MOS), Singapore (SSO) and Taiwan (TOS). The voting was based on scientific evidence and was independent of the current treatment practices and drug availability and reimbursement situations in the different Asian countries.

Anterior resection syndrome: a randomized clinical trial of a 5-HT3 receptor antagonist (ramosetron) in male patients with rectal cancer

BACKGROUND

No effective treatment exists for anterior resection syndrome (ARS) following sphincter-saving surgery for rectal cancer. This RCT assessed the safety and efficacy of a 5-HT3 receptor antagonist, ramosetron, for ARS.

METHODS

A single-centre, randomized, controlled, open-label, parallel group trial was conducted. Male patients with ARS 1 month after rectal cancer surgery or ileostomy reversal were enrolled and randomly assigned (1 : 1) to 5 μg of ramosetron (Irribow®) daily or conservative treatment for 4 weeks. Low ARS (LARS) score was calculated after randomization and 4 weeks after treatment. The study was designed as a superiority test with a primary endpoint of the proportion of patients with major LARS between the groups. Primary outcome analysis was based on the modified intention-to-treat population. Safety was assessed by monitoring adverse events during the study.

RESULTS

: A total of 100 patients were randomized to the ramosetron (49 patients) or conservative treatment group (51 patients). Two patients were excluded, and 48 and 50 patients were analysed in the ramosetron and control groups, respectively. The proportion of major LARS after 4 weeks was 58 per cent (28 of 48 patients) in the ramosetron group versus 82 per cent (41 of 50 patients) in the control group, with a difference of 23.7 per cent (95 per cent c.i. 5.58 to 39.98, P = 0.011). There were minor adverse events in five patients, which were hard stool, frequent stool or anal pain. These were not different between the two groups. There were no serious adverse events.

CONCLUSION

: Ramosetron could be safe and feasible for male patients with ARS.

TRIAL REGISTRATION NUMBER

NCT02869984 (http://www.clinicaltrials.gov).

Immunofluorescent staining of cancer spheroids and fine-needle aspiration-derived organoids

Our organoid generation technique has allowed for the development of downstream organoid applications. Here, we detail an accessible, straightforward protocol for immunofluorescent staining and imaging of thyroid cancer organoids, particularly those with tumor de-differentiation. Immunofluorescence is a powerful tool to help understand the localization of cell types within organoids and determine the interactions between those cells. As organoids have been shown to recapitulate patient tumor morphology, immunofluorescent staining and imaging of organoids allows for enhanced understanding of near in vivo structures. For complete details on the use and execution of this protocol, please refer to Lee et al. (2020) and Vilgelm et al. (2020).

Novel three-dimensional cultures provide insights into thyroid cancer behavior

Thyroid cancer has the fastest growing incidence of any cancer in the United States, as measured by the number of new cases per year. Despite advances in tissue culture techniques, a robust model for thyroid cancer spheroid culture is yet to be developed. Using eight established thyroid cancer cell lines, we created an efficient and cost-effective 3D culture system that can enhance our understanding of in vivo treatment response. We found that all eight cell lines readily form spheroids in culture with unique morphology, size, and cytoskeletal organization. In addition, we developed a high-throughput workflow that allows for drug screening of spheroids. Using this approach, we found that spheroids from K1 and TPC1 cells demonstrate significant differences in their sensitivities to dabrafenib treatment that closely model expected patient drug response. In addition, K1 spheroids have increased sensitivity to dabrafenib when compared to monolayer K1 cultures. Utilizing traditional 2D cultures of these cell lines, we evaluated the mechanisms of this drug response, showing dramatic and acute changes in their actin cytoskeleton as well as inhibition of migratory behavior in response to dabrafenib treatment. Our study is the first to describe the development of a robust spheroid system from established cultured thyroid cancer cell lines and adaptation to a high-throughput format. We show that combining 3D culture with traditional 2D methods provides a complementary and powerful approach to uncover drug sensitivity and mechanisms of inhibition in thyroid cancer.

Capecitabine plus oxaliplatin versus gemcitabine plus oxaliplatin as first-line therapy for advanced biliary tract cancers: a multicenter, open-label, randomized, phase III, noninferiority trial

BACKGROUND

Capecitabine plus oxaliplatin (XELOX) has shown modest activity and tolerable toxicity in a phase II trial for biliary tract cancers (BTCs). Meanwhile, gemcitabine plus oxaliplatin (GEMOX) has been the reference arm in recent phase II and III trials for BTCs. We aimed to investigate the efficacy of XELOX versus GEMOX as first-line therapy for advanced BCTs.

PATIENTS AND METHODS

In this open-label, randomized, phase III, noninferiority trial, we randomly selected patients with metastatic BCTs to receive GEMOX (gemcitabine 1000 mg/m2 on days 1 and 8, and oxaliplatin 100 mg/m2 on day 1) or XELOX (capecitabine 1000 mg/m2, twice daily, on days 1-14 and oxaliplatin 130 mg/m2 on day 1) as first-line treatment, given every 3 weeks, totaling eight cycles. The primary end point was to prove the noninferiority of XELOX to GEMOX in terms of 6-month progression-free survival (PFS) rate.

RESULTS

In total, 114 patients randomly received GEMOX and 108 randomly received XELOX. The median PFS was 5.3 months for the GEMOX group and 5.8 months for the XELOX group. The 6-month PFS rate was 44.5% for the GEMOX group and 46.7% for the XELOX group. The 95% confidence interval of the 6-month PFS rate difference between both groups was -12% to 16%, meeting the criteria for noninferiority of XELOX to GEMOX. There was no difference in objective response (P=0.171) and median overall survival (P=0.131) between both groups. The most common grade three to four adverse events were neutropenia and thrombocytopenia. No patient died of treatment-related causes. The XELOX group had significantly lower frequencies of hospital visits than the GEMOX group (P<0.001).

CONCLUSION

XELOX showed significant noninferiority to GEMOX in terms of 6-month PFS rate. Thus, XELOX could be an alternative first-line treatment of BCTs.

TRIAL REGISTRATION

This study was registered in ClinicalTrials.gov (number NCT01470443).

Brain Transplantation of Neural Stem Cells Cotransduced with Tyrosine Hydroxylase and GTP Cyclohydrolase 1 in Parkinsonian Rats

Neural stem cells (NSCs) of the central nervous system (CNS) recently have attracted a great deal of interest not only because of their importance in basic research on neural development, but also in terms of their therapeutic potential in neurological diseases, such as Parkinson's disease (PD). To examine if genetically modified NSCs are a suitable source for the cell and gene therapy of PD, an immortalized mouse NSC line, C17.2, was transduced with tyrosine hydroxylase (TH) gene and with GTP cyclohydrolase 1 (GTPCH1) gene, which are important enzymes in dopamine biosynthesis. The expression of TH in transduced C17.2-THGC cells was confirmed by RT-PCR, Western blot analysis, and immunocytochemistry, and expression of GTPCH1 by RT-PCR. The level of L-DOPA released by C17.2-THGC cells, as determined by HPLC assay, was 3793 pmol/106 cells, which is 760-fold higher than that produced by C17.2-TH cells, indicating that GTPCH1 expression is important for L-DOPA production by transduced C17.2 cells. Following the implantation of C17.2-THGcC NSCs into the striata of parkinsonian rats, a marked improvement in amphetamine-induced turning behavior was observed in parkinsonian rats grafted with C17.2-THGC cells but not in the control rats grafted with C17.2 cells. These results indicate that genetically modified NSCs grafted into the brain of the parkinsonian rats are capable of survival, migration, and neuronal differentiation. Collectively, these results suggest that NSCs have great potential as a source of cells for cell therapy and an effective vehicle for therapeutic gene transfer in Parkinson's disease.

Genetic analysis and genomic selection of stayability and productive life in New Zealand ewes

Genetic parameters for ewes were estimated for stayability (STAY) and productive life (Prodlife). Records from 658,871 animals from 241 seed stock or ram breeder flocks and one research flock were used to estimate parameters for ram breeder flock STAY and Prodlife. These flocks would have a culling policy based on criteria typical of a commercial enterprise, but including culls based on knowledge such as estimated breeding values. A subset of 35,688 of these animals from 4 ram breeder and one research flock was used to infer the animals that might be culled based on the perspective of a commercial flock as these flocks recorded reasons for culling. These data were used to estimate parameters for commercial flock STAY and Prodlife. Heritability for ram breeder flock STAY until age 3 to 6 yr ranged from 0.07 to 0.09. The heritability of commercial flock STAY was similar in yr 5 and 6, but lower at 0.05 (age 3) and 0.07 (age 4). Heritability of Prodlife for ram breeder flock and commercial flock was respectively 0.10 and 0.13. The genetic correlations between ram breeder flock STAY and commercial flock STAY ranged from 0.20 to 0.99. Both STAY and Prodlife were most correlated genetically with the trait number of lambs born, at about 0.4, and to a lesser degree, live weight up to the age of 12 mo for the traits analyzed with lower genetic correlations estimated for the commercial flocks. Live weight at 18 mo and fleece weight had little or no correlation with STAY and Prodlife. From the data set used to estimate genetic parameters from a ram breeder flock, 4,330 animals were genotyped with the Illumina OvineSNP50 BeadChip and the genotypes used to develop genomic predictions via genomic best linear unbiased prediction. The animals used in the training data set were multibreed, but were heavily Romney breed based. The genomic prediction accuracy for ram breeder flock STAY, according to breed, was dependent on sample size and ranged from 0.4 to 0.44 for Romney and 0.26 to 0.4 for Coopworth. Accuracies for Perendale and Composites, for which sample sizes were less, were more variable. This study has derived genetic parameters for STAY and Prodlife and investigated genomic predictions for these traits. As these traits are of low heritability, sex limited and expressed late in life genomic selection will be useful.

Gamma-tocotrienol attenuates high-fat diet-induced obesity and insulin resistance by inhibiting adipose inflammation and M1 macrophage recruitment

BACKGROUND AND OBJECTIVE

We have previously demonstrated that gamma tocotrienol (γT3) potently inhibits adipocyte hyperplasia in human adipose-derived stem cells (hASCs). In this study, our objective was to investigate the γT3 effects on early-onset obesity, inflammation and insulin resistance in vivo.

METHODS

Young C57BL/6J mice were fed a high-fat (HF) diet supplemented with 0.05% γT3 for 4 weeks. The concentrations of γT3 in plasma and adipose tissue were measured using high-performance liquid chromatography. Effects of γT3 on body weight gain, adipose volume, plasma levels of fasting glucose, insulin (enzyme-linked immunosorbent assay (ELISA)), proinflammatory cytokines (mouse cytokine array), insulin signaling (western blotting) and gene expression (quantitative real-time PCR, qPCR) in the liver and adipose tissue were examined. Influences of γT3 on [3H]-2-deoxyglucose uptake and lipopolysaccharide (LPS)-mediated NFκB signaling (western blotting) were assessed in hASCs. Effects of γT3 on macrophage M1/M2 activation were investigated using qPCR in mouse bone marrow-derived macrophages.

RESULTS

After a 4-week treatment, γT3 accumulated in adipose tissue and reduced HF diet-induced weight gain in epididymal fat, mesenteric fat and the liver. Compared with HF diet-fed mice, HF+γT3-fed mice were associated with (1) decreased plasma levels of fasting glucose, insulin and proinflammatory cytokines, (2) improved glucose tolerance and (3) enhanced insulin signaling in adipose tissue. There were substantial decreases in macrophage specific markers, and monocyte chemoattractant protein-1, indicating that γT3 reduced the recruitment of adipose tissue macrophages (ATMs). In addition, γT3 treatment in human adipocytes resulted in (1) activation of insulin-stimulated glucose uptake and (2) a significant suppression of MAP kinase and NFκB activation. In parallel, γT3 treatment led to a reduction of LPS-mediated M1 macrophage polarization.

CONCLUSION

Our results demonstrated that γT3 ameliorates HF diet-mediated obesity and insulin resistance by inhibiting systemic and adipose inflammation, as well as ATM recruitment.

Towards genomic selection for facial eczema disease tolerance in the New Zealand sheep industry

Pithomycotoxicosis, more commonly known as facial eczema (FE), is a liver disease that occurs predominantly in New Zealand because of its toxigenic Pithomyces chartarum strains. The first reported case was in sheep in 1887. Since the 1930s, a number of studies have been conducted in an attempt to mitigate the problems FE has on the sheep and dairy industries. The research in these studies included work on fungicide and biological control of the saprophytic fungus, use of different pasture plants to inhibit fungal growth, stock management with respect to pasture fungal spore counts and the use of zinc prophylaxis on animals. The finding that there was a genetic basis in FE sensitivity in sheep prompted research for a genetic approach to mitigation in the form of a diagnostic DNA test for susceptibility to the disease. Recently, we have used the Illumina OvineSNP50 BeadChip to develop a genome-enabled prediction approach to screen for FE-tolerant sheep. Our current best genomic prediction for FE is for the Romney breed and has an accuracy of 0.38. This prediction accuracy is not as high as the individual accuracy gained by an artificial challenge test (0.64). However, it has the advantage of being a non-invasive test and can be provided as part of genomic testing for other traits at minimal cost.

Epidermal regeneration by ent-16α, 17-dihydroxy-kauran-19-oic acid isolated from Siegesbeckia pubescens

OBJECTIVES

  Keratinocyte stem/progenitor cells (KSCs) are known to regenerate epidermal tissue which they perform through to their great regenerative capacity.

MATERIALS AND METHODS

  Because stimulation of resident KSCs may regenerate epidermal tissue, we devised a strategy to find an appropriate KSC activator from natural products and to develop it as a skin-rejuvenating agent.

RESULTS

  Ent-16α, 17-dihydroxy-kauran-19-oic acid (DHK) isolated from Siegesbeckia pubescens exhibited a KSC-stimulating effect during screening of natural products. DHK increased proliferation and migration of KSCs using the Akt/ERK pathway. We further examined the mechanism of KSC stimulation and found that phosphorylation of Y1068 epithelial growth factor receptor (EGFR) was significantly increased. Functional inhibition of EGFR using neutralizing antibody and a chemical inhibitor, AG1478, attenuated DHK-induced KSC stimulation. In a 3D culture model of KSCs, DHK treatment significantly induced establishment of fully stratified epidermis and increased numbers of p63-positive cells. Likewise, DHK treatment significantly accelerated healing of epidermal wounds created by laser and dermatome, and increased p63-positive cells, in animal models.

CONCLUSION

  Collectively, these results indicate that DHK regenerates epidermal tissue mainly through EGFR phosphorylation. As DHK has diverse advantages over recombinant growth factors for commercialization (that is long-term stability and skin permeability), DHK might be applied to wound-healing agents and to a basic materials used in cosmetics.

Efficacy and safety of sitagliptin and the fixed-dose combination of sitagliptin and metformin vs. pioglitazone in drug-naïve patients with type 2 diabetes

AIM

The efficacy and safety of sitagliptin (SITA) monotherapy and SITA/metformin (MET) vs. pioglitazone (PIO) were assessed in patients with type 2 diabetes and moderate-to-severe hyperglycaemia (A1C = 7.5-12.0%).

METHODS

In an initial 12-week phase (Phase A), 492 patients were randomised 1 : 1 in a double-blind fashion to SITA (100 mg qd) or PIO (15 mg qd, up-titrated to 30 mg after 6 weeks). In Phase B (28 additional weeks), the SITA group was switched to SITA/MET (up-titrated to 50/1000 mg bid over 4 weeks) and the PIO group was up-titrated to 45 mg qd

RESULTS

At the end of Phase A, mean changes from baseline were -1.0% and -0.9% for A1C; -26.6 mg/dl and -28.0 mg/dl for fasting plasma glucose; and -52.8 mg/dl and -50.1 mg/dl for 2-h post-meal glucose for SITA and PIO, respectively. At the end of Phase B, improvements in glycaemic parameters were greater with SITA/MET vs. PIO: -1.7% vs. -1.4% for A1C (p = 0.002); -45.8 mg/dl vs. -37.6 mg/dl for fasting plasma glucose (p = 0.03); -90.3 mg/dl vs. -69.1 mg/dl for 2-h postmeal glucose (p = 0.001); and 55.0% vs. 40.5% for patients with A1C < 7% (p = 0.004). A numerically higher incidence of gastrointestinal adverse events and a significantly lower incidence of oedema were observed with SITA/MET vs. PIO. The incidence of hypoglycaemia was similarly low in both groups. Body weight decreased with SITA/MET and increased with PIO (-1.1 kg vs. 3.4 kg; p < 0.001).

CONCLUSION

Improvements in glycaemic control were greater with SITA/MET vs. PIO, with weight loss vs. weight gain. Both treatments were generally well tolerated.

Direct observations of interstellar H, He, and O by the Interstellar Boundary Explorer

Neutral gas of the local interstellar medium flows through the inner solar system while being deflected by solar gravity and depleted by ionization. The dominating feature in the energetic neutral atom Interstellar Boundary Explorer (IBEX) all-sky maps at low energies is the hydrogen, helium, and oxygen interstellar gas flow. The He and O flow peaked around 8 February 2009 in accordance with gravitational deflection, whereas H dominated after 26 March 2009, consistent with approximate balance of gravitational attraction by solar radiation pressure. The flow distributions arrive from a few degrees above the ecliptic plane and show the same temperature for He and O. An asymmetric O distribution in ecliptic latitude points to a secondary component from the outer heliosheath.

Welfare myths: the transmission of values and work among TANF families

Both "welfare culture" arguments and structural explanations of poverty suggest that attitudes may have an effect on work and welfare outcomes. However, most scholars only examine objective behaviors and characteristics despite the fact that values are an underlying mechanism in explanations of the transmission of welfare and work behavior. Using data from a survey of recent welfare recipients in Louisiana and structural equation methods, we analyze causal relationships among family background, socioeconomic characteristics, attitudes, and two outcomes--TANF participation and employment. We find some support for the intergenerational transmission of welfare but not through values; we find no evidence that under the TANF system, values inhibit work.

Effect of kimchi powder level and drying methods on quality characteristics of breakfast sausage

This study was conducted to determine the effect of the addition of kimchi powder on the quality characteristics of meat batter and breakfast sausage. Breakfast sausages were supplemented with freeze dried kimchi powder (FKP) or hot air dried kimchi powder (HKP) at levels of 1% (FKP-1 and HKP-1) or 2% (FKP-2 and HKP-2). The emulsion stability, cooking yield, and apparent viscosity in meat batters improved with increments of kimchi powder (p<0.05). Increased levels of kimchi powder in breakfast sausage decreased the L(∗) value, pH, and springiness, and increased the a(∗) value, b(∗) value, hardness, chewiness, and gumminess (p<0.05). Sensory evaluations indicated that a higher overall acceptability was attained when the kimchi powder was added to breakfast sausage at a level of 2%.

Distribution of prion protein genotypes in breeds of sheep in New Zealand

AIM

To use an established high through-put genotyping procedure to gain an estimate of the frequency of alleles of the prion protein (PrP) gene in some common sheep breeds in New Zealand.

METHODS

Using a genotyping procedure based on matrix-assisted laser desorption ionisation-time of flight (MALDI-TOF), DNA samples from 3,024 sheep from New Zealand, including breeds such as Romney, Texel, Coopworth, Merino and mixed breed, were isolated, genotyped and the results analysed.

RESULTS

The 15 scrapie genotypes commonly reported, and derived from the five commonly reported allelic variants (ARR, ARQ, AHQ, ARH and VRQ), were all observed in the samples analysed. The estimates were indicative of the frequencies in the population of alleles present in breeds of sheep in New Zealand. There was a significant difference between the frequencies of alleles between breeds, but the ARQ, followed by the ARR allele, were, except in Carwell sheep, the most common alleles present.

CONCLUSION

This study gave an indication of the percentages of PrP gene alleles in sheep in New Zealand, including data previously unreported from breeds in this country. It is of interest because of the relatively large size of the sheep population in New Zealand compared with many countries, and it provides some useful information on the genetic susceptibility or resistance of the sheep population in New Zealand to scrapie. The frequencies of the alleles can be different for an individual breed compared between countries.

Measuring symptom load in Idiopathic Parkinson's disease

This study evaluated the symptom burden experienced by patients with Idiopathic Parkinson's Disease (IPD) by using a standard palliative care assessment tool (PACA) and comparing it with the Unified Parkinson's Disease Rating Scale (UPDRS). These tools together with the Mini-Mental State Examination, Beck Depression Inventory and the Schedule for the Evaluation of Individual Quality of Life were used in 123 IPD patients. The PACA demonstrated broad coverage of both motor and non motor symptoms (mean=14.3 symptoms per patient) whereas the UPDRS predominantly assessed motor symptoms. Implications for symptom assessment and palliative care provision in IPD are discussed.

Inflammatory markers, rather than conventional risk factors, are different between carotid and MCA atherosclerosis

BACKGROUND

The apparent differences in risk factors for intra- and extracranial atherosclerosis are unclear and the mechanisms that underlie strokes in patients with intracranial atherosclerosis are not well known. We investigated the conventional vascular risk factors as well as other factors in stroke patients with large artery atherosclerosis.

METHODS

Using diffusion weighted imaging (DWI) and vascular and cardiologic studies, we selected patients with acute non-cardioembolic cerebral infarcts within the middle cerebral artery (MCA) territory. Patients were divided into two groups: those with atherosclerotic lesions on the carotid sinus (n = 112) and those with isolated lesions on the proximal MCA (n = 160). Clinical features, risk factors, and DWI patterns were compared between groups.

RESULTS

There were no differences in conventional risk factors, but markers for inflammation were significantly higher in patients with carotid atherosclerosis than in those with isolated MCA atherosclerosis (p < 0.01 for both). After adjustments for age/sex and the severity of stroke, an inverse correlation was observed between C-reactive protein levels and MCA atherosclerosis (odds ratio 0.57 per 1 mg/dl increase; 95% confidence interval 0.35 to 0.92; p = 0.02). Internal borderzone infarcts suggestive of haemodynamic causes were the most frequent DWI pattern in patients with MCA occlusion, whereas territorial infarcts suggesting plaque ruptures were most common in those with carotid occlusion.

CONCLUSIONS

Our results indicate that inflammatory markers, rather than conventional risk factors, reveal clinical and radiological differences between patients with carotid and MCA atherosclerosis. Plaques associated with MCA atherosclerosis may be more stable than those associated with carotid atherosclerosis.

Association of the metabolic syndrome with intracranial atherosclerotic stroke

To investigate the impact of metabolic syndrome (MetSD) on the development of intracranial atherosclerotic stroke, the authors evaluated the components of the MetSD in 512 patients with stroke. The MetSD was observed most frequently in patients with intracranial atherosclerosis (p = 0.007). In multiple regression analysis, the MetSD, but not conventional risk factors, was independently associated with intracranial atherosclerosis (p = 0.005). The results suggest that treatment of metabolic abnormalities may be an important prevention strategy for intracranial atherosclerosis.

Measurements of plasma oxycodone, noroxycodone and oxymorphone levels in a patient with bilateral nephrectomy who is undergoing haemodialysis

The use of opioid analgesics in renal dysfunction is potentially problematic and many patients with end stage renal disease are unable to tolerate these medications. A greater understanding of the pharmacokinetics of opioid analgesics is vital in informing safe and effective practice. Using pharmacokinetic analysis, this case study demonstrates for the first time that oxycodone and its metabolites are removed by haemodialysis. As such, care should be taken when using oxycodone in patients undergoing haemodialysis.

Prediction of changes in memory performance by plasma homovanillic acid levels in clozapine-treated patients with schizophrenia

RATIONALE

Cognitive dysfunction in schizophrenia has been demonstrated to be dependent, in part, on dopaminergic activity. Clozapine has been found to improve some domains of cognition, including verbal memory, in patients with schizophrenia.

OBJECTIVES

This study tested the hypothesis that plasma homovanillic acid (pHVA) levels, a peripheral measure of central dopaminergic activity, would predict the change in memory performance in patients with schizophrenia treated with clozapine.

METHODS

Twenty-seven male patients with schizophrenia received clozapine treatment for 6 weeks. Verbal list learning (VLL)-Delayed Recall (VLL-DR), a test of secondary verbal memory, was administered before and after clozapine treatment. Blood samples to measure pHVA levels were collected at baseline.

RESULTS

Baseline pHVA levels were negatively correlated with change in performance on VLL-DR; the lower baseline pHVA level was associated with greater improvement in performance on VLL-DR during treatment with clozapine. Baseline pHVA levels in subjects who showed improvement in verbal memory during clozapine treatment ( n=13) were significantly lower than those in subjects whose memory performance did not improve ( n=14).

CONCLUSIONS

The results of this study indicate that baseline pHVA levels predict the ability of clozapine to improve memory performance in patients with schizophrenia.

Cognitive effects of olanzapine treatment in schizophrenia

Improvement in some but not all domains of cognition during treatment with the atypical antipsychotic drugs clozapine, quetiapine, olanzapine, and risperidone has been reported in some but not all studies. It has been recently suggested that these reports are an artifact, related to lessening of the impairment due to typical neuroleptic drugs and anticholinergic agents. The purpose of this study was to further test the hypothesis that olanzapine, an atypical antipsychotic drug reported to have anticholinergic properties, improves cognition in patients with schizophrenia, including domains of cognition related closely to work and social function (ie, verbal learning and memory) and that this improvement is independent of improvement in psychopathology. Thirty-four patients with schizophrenia who were partial responders to typical antipsychotic drug treatment were evaluated with a comprehensive neurocognitive battery, including measures of executive functioning; verbal and visual learning and memory; working memory; immediate, selective, and sustained attention; perceptual/motor processing; and motor skills prior to and following treatment with olanzapine for 6 weeks. The Brief Psychiatric Rating Scale (BPRS) was used to assess psychopathology in patients treated with typical antipsychotic drugs. Subjects were switched to olanzapine (average dose 13.4 mg, range 5-20 mg) and reassessed following 6 weeks and 6 months of treatment. Significant improvement was noted in 9 of 19 cognitive tests, including measures of selective attention, verbal learning and memory, and verbal fluency. No cognitive test was worsened by olanzapine treatment. Improvements in the BPRS Total and Positive Symptom Subscale scores were noted. Improvements in verbal learning and memory, sustained attention, and psychomotor tracking were independent of improvement in psychopathology. These data suggest that olanzapine improved some but not all cognitive deficits in schizophrenia, including verbal memory, a cognitive domain impaired by anticholinergic drugs. The basis for the improvement in cognitive scores, which should lead to improvement in role functioning if real, is discussed.

Pain management services in palliative care: a national survey

INTRODUCTION

The effective management of pain requires a multidisciplinary approach. Previous studies have suggested that around 8% of cancer patients will require interventional techniques from an anaesthetist with special interest in pain management to maximize pain control, although this percentage may increase in the cohort of patients with difficult pain syndromes under the care of specialist palliative care services. We wished to determine the experiences and views of other palliative care physicians with regard to input from specialists in pain management.

METHOD

A postal questionnaire was sent to the consultant members of the Association of Palliative Medicine.

RESULTS

Most respondents had access to 'as-required' anaesthetist consultations with 72% of respondents feeling that the frequency of consultation was adequate. However, over half of the respondents had used the services of a pain management specialist less than four times in the past year and a quarter of respondents had not been involved in a joint consultation with an anaesthetist in the past year. All respondents felt that the pain management specialist's role included advice on technical procedures but less than 25% felt that their role should extend to advice on prescribing analgesics.

DISCUSSION

There are likely to be several reasons for this apparent underutilization of specialist anaesthetist/pain management services. This survey has identified possible factors including lack of formal arrangements, lack of suitable experience and the attitudes of palliative medicine consultants.

New strategies for the diagnosis and screening of malaria

Thin and thick blood film microscopy are the "gold standard" for malaria diagnosis. In recent years, there have been important developments in malaria diagnostic tests including fluorescence microscopy of malaria parasites stained with acridine orange, dipstick immunoassays that detect species-specific parasite antigens, and more recently, detection of parasite nucleic acids after amplification by PCR. With some of these methods, sensitivities and specificities approaching and even exceeding those of the thin and thick film can be attained. In particular, PCR-based tests for plasmodium DNA or RNA are more sensitive and specific than other tests for malarial parasites. A specific application for PCR diagnosis of malaria could be blood donor screening. Clinical trials of blood donor sreening for malarial parasites by PCR are being conducted, in which pooled donor samples are screened to increase efficiency and reduce costs. Some of the new diagnostic methods may have specific applications in particular settings, depending on the purpose and location of testing, and other factors such as cost, desired sensitivity and specificity, speed and ease of use.

Remacemide hydrochloride as an add-on therapy in epilepsy: a randomized, placebo-controlled trial of three dose levels (300, 600 and 800 mg/day) in a B.I.D. regimen

Remacemide hydrochloride is a low-affinity, non-competitive NMDA receptor channel blocker under investigation for the treatment of epilepsy. This double-blind, placebo-controlled, multicentre study assessed the safety and efficacy of adjunctive remacemide hydrochloride or placebo, in adult patients with refractory epilepsy who were already taking up to three antiepileptic drugs (including an enzyme-inducer). Patients (n= 262) were randomized to one of three doses of remacemide hydrochloride (300, 600 or 800 mg/day) or placebo, in a B.I.D. regimen, for up to 14 weeks. Plasma concentrations of carbamazepine (CBZ) and phenytoin (PHT) were controlled throughout. Patients recorded their seizures on a diary card. There was an increase in the percentage of responders (defined as a reduction in seizure frequency from baseline > or = 50 %), from 15 % (9/60) with placebo, to 30 % (18/60) in the 800 mg/day group. A pairwise comparison between remacemide hydrochloride 800 mg/day and placebo was statistically significant (P = 0.049). Most reported adverse events (mainly CNS and gastrointestinal) were mild or moderate in severity and dose-dependent. Adjunctive remacemide hydrochloride treatment was associated with a higher, dose-related responder rate compared with placebo. The difference reached significance at the highest dose tested (800 mg/day). Remacemide hydrochloride was well tolerated.

An expanded cortical representation for hand movement after peripheral motor denervation

OBJECTIVES

Functional reorganisation of the motor or sensory cortex has been demonstrated in animals after section of mixed peripheral nerves. Here functional changes in the motor cortex specifically after peripheral motor denervation in humans are investigated.

METHODS

Functional MRI (fMRI) was used to study brain activation during a finger flexion-extension task in patients with a late onset, acquired pure motor neuropathy (n=6), contrasting results with those from patients with pure sensory neuropathies (n=4) or healthy controls (n=7).

RESULTS

Increases in the extent of activation in the motor cortex both ipsilateral and contralateral to the hand moved were found in the patients with motor neuropathy. The neuroanatomical localisation of the mixed contralateral sensorimotor cortex activation volume was more posterior for the patients with motor neuropathy than for the healthy controls (mean difference, 12 mm, p<0.05). The pure sensory neuropathy group by contrast showed no change in the extent of activation relative to healthy controls and a trend for more anterior primary sensorimotor cortex activation (p<0.06). To test whether the increased activation volumes found in patients with motor neuropathy were a result simply of factors such as increased effort with movement rather than the motor denervation, patients with hand weakness from inclusion body myositis (n=4) were studied while making similar hand movements. No differences in either the numbers of significantly activated voxels or in their localisation were found relative to healthy controls (n=10).

CONCLUSIONS

These results provide a novel demonstration that peripheral denervation (as distinguished from factors related to weakness) leads to functional reorganisation of the sensorimotor cortex in the adult brain. This suggests that adaptive responses to motor denervation involve the central as well as the peripheral nervous system.

Generation and characterization of immortalized human microglial cell lines: expression of cytokines and chemokines

Microglia are a major glial component of the central nervous system (CNS), play a critical role as resident immunocompetent and phagocytic cells in the CNS, and serve as scavenger cells in the event of infection, inflammation, trauma, ischemia, and neurodegeneration in the CNS. Studies of human microglia have been hampered by the difficulty of obtaining sufficient numbers of human microglia. One way to circumvent this difficulty is to establish permanent cell lines of human microglia. In the present study we report the generation of immortalized human microglial cell line, HMO6, from human embryonic telencephalon tissue using a retroviral vector encoding myc oncogene. The HMO6 cells exhibited cell type-specific antigens for microglia-macrophage lineage cells including CD11b (Mac-1), CD68, CD86 (B7-2), HLA-ABC, HLA-DR, and ricinus communis agglutinin lectin-1 (RCA), and actively phagocytosed latex beads. In addition, HMO6 cells showed ATP-induced responses similar to human primary microglia in Ca2+ influx spectroscopy. Both human primary microglia and HMO6 cells showed the similar cytokine gene expression in IL-1beta, IL-6, IL-8, IL-10, IL-12, IL-15, and TNF-alpha. Using HMO6 cells, we investigated whether activation was induced by Amyloid-beta fragments or lipopolysaccharide (LPS). Treatment of HMO6 cells with Amyloid-beta 25-35 fragment (Abeta(25-35)) or Amyloid-beta 1-42 fragment (Abeta(1-42)) led to increased expression of mRNA levels of cytokine/chemokine IL-8, IL-10, IL-12, MIP-1beta MIP-1, and MCP-1, and treatment with LPS produced same results. Expression of TNF-alpha and MIP1-alpha was not detected in unstimulated HMO6 cells, but their expression was later induced by long-term exposure to Abeta(25-35) or Abeta(1-42.) ELISA assays of spent culture media showed increased protein levels of TNF-alpha and IL-8 in HMO6 cells following treatment with Abeta(25-35) or LPS. Taken together, our results demonstrate that treatment of human primary microglia and HMO6 immortalized human microglia cell line with Abeta(25-35), Abeta(1-42) and LPS upregulate gene expression and protein production of proinflammatory cytokines and chemokines in these cells. The human microglial cell line HMO6 exhibits similar properties to those documented in human microglia and should have considerable utility as an in vitro model for the studies of human microglia in health and disease.

5-HT(1A) receptor dysfunction in female patients with schizophrenia

BACKGROUND

Serotonin (5-HT)(1A) receptors are of interest in the pathophysiology of schizophrenia (SCH) and the mechanism of action of atypical antipsychotic drugs. To test the hypothesis that 5-HT(1A) receptor responsivity is significantly different in patients with SCH compared to normal control subjects, the neuroendocrine study was performed using ipsapirone (IPS), a 5-HT(1A) partial agonist, as a probe.

METHODS

Ipsapirone 0.5 mg/kg, p.o. or placebo were administered, in random order, to patients with SCH (n = 43; 32 male) and normal controls (n = 33; 21 male). Blood samples for plasma cortisol and body temperature were obtained from 30 min before to 180 min after administration of IPS or placebo.

RESULTS

Female normal control subjects had markedly greater increases in plasma cortisol following IPS than did male control subjects. The placebo response-corrected plasma cortisol response to IPS was significantly blunted in female SCH compared to female normal control subjects (p =.0001). The IPS-stimulated plasma cortisol response in male SCH did not differ from that of male normal control subjects or female SCH. There were no significant differences in the IPS-induced hypothermia in men and women or between patients with SCH and normal control subjects. Behavioral responses to IPS, including nausea, dizziness, irritability, and feeling less well, did not differ between groups.

CONCLUSIONS

These results suggest that the post-synaptic 5-HT(1A) receptor mediated endocrine response is diminished in female SCH compared to female normal control subjects, possibly secondary to an abnormality in intracellular signal transduction mechanism.

Cloning and sequence characterisation of falcipain-2 from Plasmodium falciparum Gombak A strain (Malaysia)

In this study, the genome of the Plasmodium falciparum Gombak A strain was examined for the presence of a gene encoding falcipain-2, a cysteine protease, using homology-based polymerase chain reaction cloning. The nucleotide sequence obtained from the gene cloned (designated pFG1) is approximately 99% homologous to other falcipain-2 genes from different strains. Comparatively, it is 69% homologous to falcipain-3 genes. Direct cloning of the falcipain-2 gene and its resemblance to the reported corresponding mRNA transcript suggests the absence of introns in this gene. Sequence alignment and comparison revealed four amino acid differences at positions 15, 51, 59 and 414 in the falcipain-2 from P. falciparum Gombak A as compared to other falcipain-2 proteins from different strains.

Timing of endogenous activin-like signals and regional specification of theXenopusembryo

Signaling by activin-like ligands is important for induction and patterning of mesoderm and endoderm. We have used an antibody that specifically recognizes the phosphorylated and activated form of Smad2, an intracellular transducer of activin-like ligands, to examine how this signaling pathway patterns the early mesendoderm. In contrast to the simple expectation that activin-like signaling should be highest on the dorsal side of the gastrula stage embryo, we have found that while Smad2 phosphorylation is highest dorsally before gastrulation, signaling is attenuated dorsally and is highest on the ventral side by mid-gastrulation. Early dorsal initiation of Smad2 phosphorylation results from cooperation between the vegetally localized maternal transcription factor VegT and dorsally localized β-catenin. The subsequent ventral appearance of Smad2 phosphorylation is dependent on VegT, but not on signaling from the dorsal side. Dorsal attenuation of Smad2 phosphorylation during gastrulation is mediated by early dorsal expression of feedback inhibitors of activin-like signals.

In addition to regulation of Smad2 phosphorylation by the expression of activin-like ligands and their antagonists, the responsiveness of embryonic cells to activin-like ligands is also temporally regulated. Ectopic Vg1, Xnr1 and derrière all fail to activate Smad2 phosphorylation until after the midblastula transition, and the onset of responsiveness to these ligands is independent of transcription. Furthermore, the timing of cellular responsiveness differs for Xnr1 and derrière, and these distinct temporal patterns of responsiveness can be correlated with their distinctive phenotypic effects. These observations suggest that the timing of endogenous activin-like signaling is a determinant of patterning in the early Xenopus embryo.

Oregon physicians' attitudes about and experiences with end-of-life care since passage of the Oregon Death with Dignity Act

CONTEXT

The Oregon Death with Dignity Act, passed by ballot measure in 1994 and enacted in October 1997, legalized physician-assisted suicide for competent, terminally ill Oregonians, but little is known about the effects of the act on clinical practice or physician perspective.

OBJECTIVE

To examine Oregon physicians' attitudes toward and practices regarding care of dying patients since the passage of the Death with Dignity Act.

DESIGN, SETTING, AND PARTICIPANTS

A self-administered questionnaire was mailed in February 1999 to Oregon physicians eligible to prescribe under the act. Of 3981 eligible physicians, 2641 (66%) returned the questionnaire by August 1999.

MAIN OUTCOME MEASURES

Physicians' reports of their efforts to improve care for dying patients since 1994, their attitudes, concerns, and sources of information about participating in the Death with Dignity Act, and their conversations with patients regarding assisted suicide.

RESULTS

A total of 791 respondents (30%) reported that they had increased referrals to hospice. Of the 2094 respondents who cared for terminally ill patients, 76% reported that they made efforts to improve their knowledge of the use of pain medications in the terminally ill. Nine hundred forty-nine responding physicians (36%) had been asked by a patient if they were potentially willing to prescribe a lethal medication. Seven percent of all survey participants reported that 1 or more patients became upset after learning the physician's position on assisted suicide, and 2% reported that 1 or more patients left their care after learning the physician's position on assisted suicide. Of the 73 physicians who were willing to write a lethal prescription and who had received a request from a patient, 20 (27%) were not confident they could determine when a patient had less than 6 months to live.

CONCLUSION

Most Oregon physicians who care for terminally ill patients report that since 1994 they have made efforts to improve their ability to care for these patients and many have had conversations with patients about assisted suicide.

Development of a simplified assay for the detection of neutralizing antibodies to Japanese encephalitis virus

Japanese encephalitis virus is a common cause of viral encephalitis in Asia with an estimated 45,000 cases annually. It causes significant morbidity and mortality. It is transmitted primarily by Culex mosquitoes between birds and animals, while man is thought to be an accidental, dead-end host. Since dengue is also prevalent usually in Japanese encephalitis-endemic areas, all Japanese encephalitis positive sera must be confirmed by detecting Japanese encephalitis specific neutralizing antibodies. The plaque reduction neutralization test is the gold standard for detecting and quantifying Japanese encephalitis neutralizing antibodies. This test, however, takes about a week and is carried out in 6 or 24-well plates, which limits its usage for large-scale screening. A simplified assay was developed for the detection and quantification of Japanese encephalitis neutralizing antibodies. The assay, which is carried out in 96-well plates, would be suitable for use in the mass screening of the population's immunity level as well as for use in vaccine efficacy studies.

Lost-a-fin encodes a type I BMP receptor, Alk8, acting maternally and zygotically in dorsoventral pattern formation

TGFbeta signaling pathways of the bone morphogenetic protein (BMP) subclass are essential for dorsoventral pattern formation of both vertebrate and invertebrate embryos. Here we determine by chromosomal mapping, linkage analysis, cDNA sequencing and mRNA rescue that the dorsalized zebrafish mutant lost-a-fin (laf) is defective in the gene activin receptor-like kinase 8 (alk8), which encodes a novel type I TGFbeta receptor. The alk8 mRNA is expressed both maternally and zygotically. Embyros that lack zygotic, but retain maternal Laf/Alk8 activity, display a weak dorsalization restricted to the tail and die by 3 days postfertilization. We rescued the laf dorsalized mutant phenotype by alk8 mRNA injection and generated homozygous laf/alk8 mothers to investigate the maternal role of Laf/Alk8 activity. Adult fish lacking Laf/Alk8 activity are fertile, exhibit a growth defect and are significantly smaller than their siblings. Embryos derived from homozygous females, which lack both maternal and zygotic Laf/Alk8 activity, display a strongly dorsalized mutant phenotype, no longer limited to the tail. These mutant embryos lack almost all gastrula ventral cell fates, with a concomitant expansion of dorsal cell types. During later stages, most of the somitic mesoderm and neural tissue circumscribe the dorsoventral axis of the embryo. Zygotic laf/alk8 mutants can be rescued by overexpression of the BMP signal transducer Smad5, but not the Bmp2b or Bmp7 ligands, consistent with the Laf/Alk8 receptor acting within a BMP signaling pathway, downstream of a Bmp2b/Bmp7 signal. Antibodies specific for the phosphorylated, activated form of Smad1/5, show that BMP signaling is nearly absent in gastrula lacking both maternal and zygotic Laf/Alk8 activity, providing further evidence that Laf/Alk8 transduces a BMP signal. In total, our work strongly supports the role of Laf/Alk8 as a type I BMP receptor required for the specification of ventral cell fates.

Children's access to dental care in Connecticut's Medicaid managed care program

OBJECTIVE

To describe dental care utilization and access problems in Connecticut's Medicaid managed care program, using quantitative and qualitative research methods.

METHODS

Using Medicaid managed care enrollment and encounter data from Connecticut, utilization rates for preventive care and treatment services are determined for 87,181 children who were continuously enrolled in Medicaid managed care for 1 year in 1996-97. Sociodemographic and enrollment factors associated with utilization are identified using bivariate and multivariate methods. Dental providers and practices where children received services are described. Qualitative methods are used to characterize problems experienced by families seeking dental care during the study period.

RESULTS

Only 30.5% of children continuously enrolled in Medicaid managed care for 1 year received any preventive dental services; 17.8% received any treatment services. Children who received preventive care were eight times more likely to have received treatment services. Utilization was higher among (a) younger children, (b) children who lived in Hartford and in other counties served by public dental clinics, and (c) children enrolled in health plans that did not subcontract for administration of dental services. Just 5% of providers, primarily those in public dental clinics, performed 50% of the services. Families whose children needed care encountered significant administrative and logistical problems when trying to find willing providers and obtain appointments.

CONCLUSIONS

Access to dental care is a problem for children in Connecticut's Medicaid managed care program. Several features of managed care have negatively affected access. Public dental clinics served many children across the state and contributed to higher utilization of preventive care and treatment services among children living in Hartford.

Pretreatment with glycine reduces the severity of warm intestinal ischemic-reperfusion injury in the rat

Free jejunal flaps may experience adverse effects immediately after revascularization because of ischemic-reperfusion injury. In this study the authors evaluated the ability of glycine to protect the small intestine against the effects of a warm ischemic-reperfusion injury. Male Wistar rats (N = 30) were randomized to either a baseline group (no intervention), a control group (local arterial infusion with normal saline), or a glycine group (local arterial infusion with 20% glycine). Pretreatment with 20% glycine increased significantly (p < 0.05) mucosal protein and deoxyribonucleic acid content, reduced intestinal myeloperoxidase activity, and maintained mucosal glutaminase activity. These results indicate that some of the indicators of ischemic-reperfusion injury are improved by pretreatment with a 20% glycine solution.

The blunted plasma cortisol response to apomorphine and its relationship to treatment response in patients with schizophrenia

The adrenocorticotropic hormone (ACTH) and cortisol responses to apomorphine (APO), a direct acting dopamine (DA) agonist, have been reported to be significantly blunted in neuroleptic-free patients with schizophrenia (SCH). This study primarily examined the cortisol, but also the prolactin (PRL) and growth hormone (GH), response to APO in patients with SCH compared to normal controls, as well as the relationship between endocrine measures and response to antipsychotic drug treatment. APO, 0.01 mg/kg, or placebo was administered to 51-98 patients with SCH and 15-25 normal controls. Psychopathology was assessed at the baseline and six weeks after drug treatment. The plasma cortisol response to APO was markedly blunted in patients with SCH compared to normal controls. Patients who responded to six weeks of treatment with antipsychotic drugs had a higher cortisol response to APO compared to non-responders. The plasma GH, but not PRL, response to APO was blunted in male patients with SCH. Neither plasma GH nor PRL responses to APO were related to treatment response at six weeks. These results provide further evidence of dopaminergic dysfunction in SCH. Furthermore, the APO-stimulated cortisol response may be predictive of subsequent clinical response to antipsychotic drug treatment.

Retrospective study of the use of hydromorphone in palliative care patients with normal and abnormal urea and creatinine

An uncontrolled retrospective study was conducted looking at the use of oral controlled-release hydromorphone in palliative care patients. Over a 2-year period 55 patients were switched to hydromorphone therapy, and the efficacy and outcomes were assessed. Urea and electrolyte measurements were also recorded at the time of opioid switch and renal impairment defined as urea > 10.5 mmol/l and/or creatinine > or = 101 mmol/l. This group of 29 patients with abnormal urea and/or creatinine (Group 1) was compared with the remaining 26 patients (Group 2) who had normal urea and creatinine. The major reasons for change to hydromorphone were side-effects (cognitive/drowsiness/nausea) on previous therapy. Following a switch to hydromorphone these side-effects improved in over 80% of patients (n = 55). Comparison between Group 1 and 2 demonstrated a significant difference in renal function but no significant differences in reasons for change, dose of opioids or response to change (over 80% improvement following opioid switch). We conclude that hydromorphone is a flexible second-line alternative to morphine that is particularly useful when intolerable side-effects are experienced with other opioids. In renal impairment (including two patients with end-stage renal failure) we found hydromorphone to be safe and effective. Further clinical and pharmacokinetic studies are required.

Periorbital congenital melanocytic nevus associated with ankyloblepharon

We report periorbital congenital melanocytic nevus associated with ankyloblepharon in a 2-month-old boy. This unusual presentation may be explained by the assumption that the development of the congenital melanocytic nevus (CMN) in utero was related to the failure of normal eyelid separation, which occurs around the 20th week of gestation.

Utilization of a murine model to investigate the molecular process of transphyseal bone formation

The purpose of this investigation was to establish a model that allows efficient and broad-based molecular studies of bony bridge formation and to correlate basic histologic findings and novel in situ hybridization assays with previous studies. We disrupted the hindlimb tibial physis of skeletally immature mice. Histologic examination of the damaged limbs at weeks 1, 3, and 5 using the HBQ method and in situ hybridization for col2, col1O, Indian hedgehog (ihh), and vascular endothelial growth factor (VEGF) were consistent with previous reports in non-murine models documenting initial evidence of ossification at 1 week post-injury and a fully ossified bony bridge at 3 weeks. In situ hybridization assays documented the absence of ihh and VEGF in the disrupted region, suggesting that bone formation is not occurring via the process of endochondral ossification. We conclude that a murine model provides an excellent opportunity for further examination of the molecular mechanism of induced transphyseal ossification.

Sequencing and characterization of a novel serine metalloprotease from Burkholderia pseudomallei

Burkholderia pseudomallei, a Gram-negative bacterium is found in the soil and water, mainly in Southeast Asia and Northern Australia. It is responsible for melioidosis in human and animals. The bacteria produce several potential virulent factors such as extracellular protease, hemolysin, lipase and lecithinase. The isolation of virulence genes and the study of their functions will contribute to our understanding of bacterial pathogenesis. Previous studies have implicated protease as a contributing virulence factor in the pathogenesis of some bacteria. Three out of 5000 clones screened from a genomic DNA library of B. pseudomallei were found to express protease activity. The clones were found to have the same sequence. The nucleotide sequence revealed an open reading frame (designated as metalloprotease A, mprA) encoding a 500-amino acid protein, MprA, with an estimated molecular mass of 50241 Da. The predicted amino acid sequence shares homology with the subtilisin family of serine proteases.

Physician orders for life-sustaining treatment (POLST): outcomes in a PACE program. Program of All-Inclusive Care for the Elderly

OBJECTIVES

To evaluate whether terminal care was consistent with Physician Orders for Life-Sustaining Treatment (POLST), a preprinted and signed doctor's order specifying treatment instructions in the event of serious illness for CPR, levels of medical intervention, antibiotics, IV fluids, and feeding tubes.

DESIGN

Retrospective chart review.

SETTING

ElderPlace, a Program of All-Inclusive Care for the Elderly (PACE) site in Portland, Oregon.

PARTICIPANTS

All ElderPlace participants who died in 1997 were eligible (n = 58). Reasons for exclusion were no POLST (1), missing POLST (1), and insufficient documentation of care (2).

MEASUREMENTS

POLST instructions for each participant and whether or not each of the treatments addressed by the POLST was administered in the final 2 weeks of life.

RESULTS

The POLST specified "do not resuscitate" for 50 participants (93%); CPR use was consistent with these instructions for 49 participants (91%). "Comfort care" was the designated level of medical intervention in 13 cases, "limited interventions" in 18, "advanced interventions" in 18, and "full interventions" in 5. Interventions administered were at the level specified in 25 cases (46%); at a less invasive level in 18 (33%), and at a more invasive level in 11 (20%). Antibiotic administration was consistent with POLST instructions for 86% of 28 subjects who had infections in the last 2 weeks of life, and less invasive for 14%. Care matched POLST instructions in 84% of cases for IV fluids and 94% for feeding tubes.

CONCLUSIONS

POLST completion in ElderPlace exceeds reported advance directive rates. Care matched POLST instructions for CPR, antibiotics, IV fluids, and feeding tubes more consistently than previously reported for advance directive instructions. Medical intervention level was consistent with POLST instructions for less than half the participants, however. We conclude that the POLST is effective for limiting the use of some life-sustaining interventions, but that the factors that lead physicians to deviate from patients' stated preferences merit further investigation.