Relevance of ATM Status in Driving Sensitivity to DNA Damage Response Inhibitors in Patient-Derived Xenograft Models

Ataxia-telangiectasia mutated gene (ATM) is a key component of the DNA damage response (DDR) and double-strand break repair pathway. The functional loss of ATM (ATM deficiency) is hypothesised to enhance sensitivity to DDR inhibitors (DDRi). Whole-exome sequencing (WES), immunohistochemistry (IHC), and Western blotting (WB) were used to characterise the baseline ATM status across a panel of ATM mutated patient-derived xenograft (PDX) models from a range of tumour types. Antitumour efficacy was assessed with poly(ADP-ribose)polymerase (PARP, olaparib), ataxia- telangiectasia and rad3-related protein (ATR, AZD6738), and DNA-dependent protein kinase (DNA-PK, AZD7648) inhibitors as a monotherapy or in combination to associate responses with ATM status. Biallelic truncation/frameshift ATM mutations were linked to ATM protein loss while monoallelic or missense mutations, including the clinically relevant recurrent R3008H mutation, did not confer ATM protein loss by IHC. DDRi agents showed a mixed response across the PDX's but with a general trend toward greater activity, particularly in combination in models with biallelic ATM mutation and protein loss. A PDX with an ATM splice-site mutation, 2127T > C, with a high relative baseline ATM expression and KAP1 phosphorylation responded to all DDRi treatments. These data highlight the heterogeneity and complexity in describing targetable ATM-deficiencies and the fact that current patient selection biomarker methods remain imperfect; although, complete ATM loss was best able to enrich for DDRi sensitivity.

Direct targeting of FOXP3 in Tregs with AZD8701, a novel antisense oligonucleotide to relieve immunosuppression in cancer

BACKGROUND

The Regulatory T cell (Treg) lineage is defined by the transcription factor FOXP3, which controls immune-suppressive gene expression profiles. Tregs are often recruited in high frequencies to the tumor microenvironment where they can suppress antitumor immunity. We hypothesized that pharmacological inhibition of FOXP3 by systemically delivered, unformulated constrained ethyl-modified antisense oligonucleotides could modulate the activity of Tregs and augment antitumor immunity providing therapeutic benefit in cancer models and potentially in man.

METHODS

We have identified murine Foxp3 antisense oligonucleotides (ASOs) and clinical candidate human FOXP3 ASO AZD8701. Pharmacology and biological effects of FOXP3 inhibitors on Treg function and antitumor immunity were tested in cultured Tregs and mouse syngeneic tumor models. Experiments were controlled by vehicle and non-targeting control ASO groups as well as by use of multiple independent FOXP3 ASOs. Statistical significance of biological effects was evaluated by one or two-way analysis of variance with multiple comparisons.

RESULTS

AZD8701 demonstrated a dose-dependent knockdown of FOXP3 in primary Tregs, reduction of suppressive function and efficient target downregulation in humanized mice at clinically relevant doses. Surrogate murine FOXP3 ASO, which efficiently downregulated Foxp3 messenger RNA and protein levels in primary Tregs, reduced Treg suppressive function in immune suppression assays in vitro. FOXP3 ASO promoted more than 70% reduction in FOXP3 levels in Tregs in vitro and in vivo, strongly modulated Treg effector molecules (eg, ICOS, CTLA-4, CD25 and 4-1BB), and augmented CD8⁺ T cell activation and produced antitumor activity in syngeneic tumor models. The combination of FOXP3 ASOs with immune checkpoint blockade further enhanced antitumor efficacy.

CONCLUSIONS

Antisense inhibitors of FOXP3 offer a promising novel cancer immunotherapy approach. AZD8701 is being developed clinically as a first-in-class FOXP3 inhibitor for the treatment of cancer currently in Ph1a/b clinical trial (NCT04504669).

ATR Inhibitor AZD6738 (Ceralasertib) Exerts Antitumor Activity as a Monotherapy and in Combination with Chemotherapy and the PARP Inhibitor Olaparib

AZD6738 (ceralasertib) is a potent and selective orally bioavailable inhibitor of ataxia telangiectasia and Rad3-related (ATR) kinase. ATR is activated in response to stalled DNA replication forks to promote G2-M cell-cycle checkpoints and fork restart. Here, we found AZD6738 modulated CHK1 phosphorylation and induced ATM-dependent signaling (pRAD50) and the DNA damage marker γH2AX. AZD6738 inhibited break-induced replication and homologous recombination repair. In vitro sensitivity to AZD6738 was elevated in, but not exclusive to, cells with defects in the ATM pathway or that harbor putative drivers of replication stress such as CCNE1 amplification. This translated to in vivo antitumor activity, with tumor control requiring continuous dosing and free plasma exposures, which correlated with induction of pCHK1, pRAD50, and γH2AX. AZD6738 showed combinatorial efficacy with agents associated with replication fork stalling and collapse such as carboplatin and irinotecan and the PARP inhibitor olaparib. These combinations required optimization of dose and schedules in vivo and showed superior antitumor activity at lower doses compared with that required for monotherapy. Tumor regressions required at least 2 days of daily dosing of AZD6738 concurrent with carboplatin, while twice daily dosing was required following irinotecan. In a BRCA2-mutant patient-derived triple-negative breast cancer (TNBC) xenograft model, complete tumor regression was achieved with 3 to5 days of daily AZD6738 per week concurrent with olaparib. Increasing olaparib dosage or AZD6738 dosing to twice daily allowed complete tumor regression even in a BRCA wild-type TNBC xenograft model. These preclinical data provide rationale for clinical evaluation of AZD6738 as a monotherapy or combinatorial agent.

SIGNIFICANCE

This detailed preclinical investigation, including pharmacokinetics/pharmacodynamics and dose-schedule optimizations, of AZD6738/ceralasertib alone and in combination with chemotherapy or PARP inhibitors can inform ongoing clinical efforts to treat cancer with ATR inhibitors.

Macrophage Activation Status Rather than Repolarization Is Associated with Enhanced Checkpoint Activity in Combination with PI3Kγ Inhibition

Suppressive myeloid cells mediate resistance to immune checkpoint blockade. PI3Kγ inhibition can target suppressive macrophages, and enhance efficacy of immune checkpoint inhibitors. However, how PI3Kγ inhibitors function in different tumor microenvironments (TME) to activate specific immune cells is underexplored. The effect of the novel PI3Kγ inhibitor AZD3458 was assessed in preclinical models. AZD3458 enhanced antitumor activity of immune checkpoint inhibitors in 4T1, CT26, and MC38 syngeneic models, increasing CD8⁺ T-cell activation status. Immune and TME biomarker analysis of MC38 tumors revealed that AZD3458 monotherapy or combination treatment did not repolarize the phenotype of tumor-associated macrophage cells but induced gene signatures associated with LPS and type II INF activation. The activation biomarkers were present across tumor macrophages that appear phenotypically heterogenous. AZD3458 alone or in combination with PD-1-blocking antibodies promoted an increase in antigen-presenting (MHCII⁺) and cytotoxic (iNOS⁺)-activated macrophages, as well as dendritic cell activation. AZD3458 reduced IL-10 secretion and signaling in primary human macrophages and murine tumor-associated macrophages, but did not strongly regulate IL-12 as observed in other studies. Therefore, rather than polarizing tumor macrophages, PI3Kγ inhibition with AZD3458 promotes a cytotoxic switch of macrophages into antigen-presenting activated macrophages, resulting in CD8 T-cell-mediated antitumor activity with immune checkpoint inhibitors associated with tumor and peripheral immune activation.

Childhood infections, vaccinations, and tonsillectomy and risk of first clinical diagnosis of CNS demyelination in the Ausimmune Study

BACKGROUND

The association between childhood vaccinations and infections and risk of multiple sclerosis is unclear; few studies have considered age at vaccination/infection.

OBJECTIVE

To explore age-related associations between childhood vaccinations, infection and tonsillectomy and risk of a first clinical diagnosis of CNS demyelination.

METHODS

Data on case (n = 275, 76.6% female; mean age 38.6 years) and age- and sex-matched control (n = 529) participants in an incident population-based case-control study included self-reported age at time of childhood vaccinations, infections, and tonsillectomy. Conditional logistic regression models were used to calculate adjusted odds ratios (AOR) and 95% confidence intervals (CI).

RESULTS

Poliomyelitis vaccination prior to school-age was associated with increased risk of a first clinical diagnosis of CNS demyelination (AOR = 2.60, 95%CI 1.02-6.68), based on a very small unvaccinated reference group. Late (11-15 years) rubella vaccination (compared to none) was associated with lower odds of being a case (AOR = 0.47, 95%CI 0.27-0.83). Past infectious mononucleosis at 11-15 years (AOR = 2.84, 95%CI 1.0-7.57) and 16-20 years (AOR = 1.92, 95%CI 1.12-3.27) or tonsillectomy in adolescence (11-15 years: AOR = 2.45, 95%CI 1.12-5.35), including after adjustment for IM, were associated with increased risk of a first clinical diagnosis of CNS demyelination.

CONCLUSIONS

Age at vaccination, infection or tonsillectomy may alter the risk of subsequent CNS demyelination. Failing to account for age effects may explain inconsistencies in past findings.

Longitudinal immune characterization of syngeneic tumor models to enable model selection for immune oncology drug discovery

Background

The ability to modulate immune-inhibitory pathways using checkpoint blockade antibodies such as αPD-1, αPD-L1, and αCTLA-4 represents a significant breakthrough in cancer therapy in recent years. This has driven interest in identifying small-molecule-immunotherapy combinations to increase the proportion of responses. Murine syngeneic models, which have a functional immune system, represent an essential tool for pre-clinical evaluation of new immunotherapies. However, immune response varies widely between models and the translational relevance of each model is not fully understood, making selection of an appropriate pre-clinical model for drug target validation challenging.

Methods

Using flow cytometry, O-link protein analysis, RT-PCR, and RNAseq we have characterized kinetic changes in immune-cell populations over the course of tumor development in commonly used syngeneic models.

Results

This longitudinal profiling of syngeneic models enables pharmacodynamic time point selection within each model, dependent on the immune population of interest. Additionally, we have characterized the changes in immune populations in each of these models after treatment with the combination of α-PD-L1 and α-CTLA-4 antibodies, enabling benchmarking to known immune modulating treatments within each model.

Conclusions

Taken together, this dataset will provide a framework for characterization and enable the selection of the optimal models for immunotherapy combinations and generate potential biomarkers for clinical evaluation in identifying responders and non-responders to immunotherapy combinations.

Pharmacology of the ATM Inhibitor AZD0156: Potentiation of Irradiation and Olaparib Responses Preclinically

AZD0156 is a potent and selective, bioavailable inhibitor of ataxia-telangiectasia mutated (ATM) protein, a signaling kinase involved in the DNA damage response. We present preclinical data demonstrating abrogation of irradiation-induced ATM signaling by low doses of AZD0156, as measured by phosphorylation of ATM substrates. AZD0156 is a strong radiosensitizer in vitro, and using a lung xenograft model, we show that systemic delivery of AZD0156 enhances the tumor growth inhibitory effects of radiation treatment in vivo Because ATM deficiency contributes to PARP inhibitor sensitivity, preclinically, we evaluated the effect of combining AZD0156 with the PARP inhibitor olaparib. Using ATM isogenic FaDu cells, we demonstrate that AZD0156 impedes the repair of olaparib-induced DNA damage, resulting in elevated DNA double-strand break signaling, cell-cycle arrest, and apoptosis. Preclinically, AZD0156 potentiated the effects of olaparib across a panel of lung, gastric, and breast cancer cell lines in vitro, and improved the efficacy of olaparib in two patient-derived triple-negative breast cancer xenograft models. AZD0156 is currently being evaluated in phase I studies (NCT02588105).

Modeling Dose and Schedule Effects of AZD2811 Nanoparticles Targeting Aurora B Kinase for Treatment of Diffuse Large B-cell Lymphoma

Barasertib (AZD1152), a pro-drug of the highly potent and selective Aurora B kinase inhibitor AZD2811, showed promising clinical activity in relapsed/refractory diffuse large B-cell lymphoma (DLBCL) patients administered as a 4-day infusion. To improve potential therapeutic benefit of Aurora B kinase inhibition, a nanoparticle formulation of AZD2811 has been developed to address limitations of repeated intravenous infusion. One of the challenges with the use of nanoparticles for chronic treatment of tumors is optimizing dose and schedule required to enable repeat administration to sustain tumor growth inhibition. AZD2811 gives potent cell growth inhibition across a range of DLBCL cells lines in vitro In vivo, repeat administration of the AZD2811 nanoparticle gave antitumor activity at half the dose intensity of AZD1152. Compared with AZD1152, a single dose of AZD2811 nanoparticle gave less reduction in pHH3, but increased apoptosis and reduction of cells in G1 and G₂-M, albeit at later time points, suggesting that duration and depth of target inhibition influence the nature of the tumor cell response to drug. Further exploration of the influence of dose and schedule on efficacy revealed that AZD2811 nanoparticle can be used flexibly with repeat administration of 25 mg/kg administered up to 7 days apart being sufficient to maintain equivalent tumor control. Timing of repeat administration could be varied with 50 mg/kg every 2 weeks controlling tumor control as effectively as 25 mg/kg every week. AZD2811 nanoparticle can be administered with very different doses and schedules to inhibit DLBCL tumor growth, although maximal tumor growth inhibition was achieved with the highest dose intensities.

A qualitative study exploring views and experiences of people with stroke undergoing transcranial direct current stimulation and upper limb robot therapy

Background Neurorehabilitation technologies used mainly in research such as robot therapy (RT) and transcranial direct current stimulation (tDCS) can promote upper limb motor recovery after stroke. Understanding the feasibility and efficacy of stroke rehabilitation technologies for upper limb impairments is crucial for effective implementation in practice. Small studies have explored views of RT by people with stroke; however experiences of people receiving tDCS in combination with RT have never been explored. Objective To explore views and experiences of people with sub-acute and chronic stroke that had previously taken part in a randomised controlled trial involving tDCS and RT for their impaired upper limb. Methods An interview study includes open and closed questions. Face-to-face interviews were audio recorded. Open-ended question responses were transcribed and analyzed using thematic analysis; closed questions were analyzed using descriptive analysis. Results Participants felt that RT was enjoyable (90%) and beneficial for their affected arm (100%). From the open question data, it was found that the intervention was effective for the impaired arm especially in the sub-acute stage. Main reported concerns were that tDCS caused painful, itching and burning sensations and RT was sometimes tiring and difficult. Participants recommended that future research should focus on designing a more comfortable method of tDCS and develop a robot that promotes hand movements. Conclusions This study provides new knowledge about the benefits and barriers associated with these technologies which are crucial to the future effective implementation of these tools in practice.

Abstract 4302: Analysis of the dose and schedule dependence of tumor kill in nonclinical tumour models after treatment with the WEE1 inhibitor AZD1775

AZD1775 is a highly selective, small-molecule inhibitor of WEE1 being developed to treat patients with advanced solid tumors, as monotherapy and in combination with olaparib (Lynparza). Previously a mathematical model was developed using data from patient-derived explant (PDX) and xenografted models with a range of sensitivities to AZD1775. This mathematical model could describe the dose and schedule dependency of pharmacokinetics, pCDK1 reduction in tumor and anti-tumor activity. This was for a dose range of 30mg/kg-120mg/kg dosed p.o. on a range of schedules from 3 days on 4 days off to 5 days on 9 days off. The model was then used to rank the potential effectiveness of each dosing regimen by calculating the fraction of tumor killed per week at doses resulting in drug exposure comparable to that observed in the clinic. This calculation was performed by integrating over time the rate of tumor kill predicted by the model. This analysis was complimented with a log cell kill (LCK) analysis using post treatment regrowth data to estimate in a more empirical manner the fraction of tumor killed over the treatment period. Specifically, if TC and TT are the times it takes the controls and treated tumors to grow to a prescribed volume and DT is the doubling time of control tumors then LCK=(TT-TC)/(2.3xDT). The analysis demonstrated that across the data set there was a consistent trend of increased LCK with dose level and number of days dosing in a week. The LCK values for each regimen were normalized by the total number of doses administered, to give an LCK per dose. There appeared to be a consistent LCK per dose level across the dose range considered. Interestingly, there was a greater than linear increase of LCK with increasing dose level. This was consistent with the observation that higher doses with shorter durations of dosing, were at least as active as more chronically administered lower doses. In the TNBC HBCx17 (Xentech) model, over a four-week period 60mg/kg dosed 5 days per week results in an LCK of 0.5 (70% killed) whereas 90mg/kg dosed 3 days per week has an LCK of 0.75 (83% killed). The same relationship was derived from the model simulated fraction tumor kill: higher doses generated significantly larger proportions of tumor kill, thus requiring shorter periods of dosing for the same net effect. The analysis drew greater differentiation between regimen than could be achieved by a tumor growth inhibition (TGI) analysis: where regressions were observed there were a few percentage point differences in TGI between regimen, but up to an order of magnitude difference in LCK. By concentrating on predicting potential cell kill, regimens were identified that are more likely to lead to responses in the clinic. The insights from this analysis have informed recommended dose and schedule for subsequent efficacy expansions.

Citation Format: James William Thomas Yates, Elaine Cadogan, Jennifer I. Hare, Adina M. Hughes, Urszula M. Polanska, Mark J. O'Connor, Susan E. Critchlow. Analysis of the dose and schedule dependence of tumor kill in nonclinical tumour models after treatment with the WEE1 inhibitor AZD1775 [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 4302.

Abstract 2494: ATR inhibitor AZD6738 as monotherapy and in combination with olaparib or chemotherapy: defining pre-clinical dose-schedules and efficacy modelling

Introduction: AZD6738 is a potent and selective oral inhibitor of the ataxia telangiectasia and rad3 related (ATR) protein kinase. ATR has a key role in the DNA replication stress response (RSR) pathway of DNA repairby facilitating the recovery and repair of potentially cytotoxic persistent, stalled DNA replication forks. Inhibition of ATR leads to the inability to resolve replication associated damage and the accumulation of DNA strand breaks, which if remains unrepaired leads to cell death. AZD6738 is currently in Phase I/II clinical trials being evaluated as a monotherapy and in combination with novel agents olaparib / Lynparza (PARP DNA damage response inhibitor), durvalumab (PD-L1 immune checkpoint inhibitor) and DNA-damaging agents such as carboplatin and ionising radiation. Critical in helping to guide the clinical usage of AZD6738 and maximise patient benefit, pre-clinical studies were performed to determine optimal doses and schedules as monotherapy and in combination with olaparib and carboplatin.

Experimental procedures: Human cancer cell lines, xenograft and patient-derived explant (PDX) models of non-small cell lung cancer (NSCLC), head & neck squamous cell carcinoma (HNSCC), and triple-negative breast cancer (TNBC) were tested comparing once daily versus twice daily dosing, the number of consecutive days dosing (3 days/week, 5 days/week, continuous) and co-dosing versus sequential or intermittent dosing with AZD6738 alone or in combination with olaparib or carboplatin. The magnitude and duration of anti-tumour responses were then compared with AZD6738 mouse pharmacokinetic (PK), pharmacodynamic (PD) and in vitro target (IC) / growth inhibition (GI) profiles.

Results: A mathematical model was derived which adequately described the AZD6738 PK/PD-efficacy relationship. This modelling confirms that duration of cover (time) above cellular ATR target inhibition thresholds (IC90 pCHK1 / GI90) per day, rather than Cmax or exposures per se, is the major determinant of anti-tumour responses. As monotherapy, in sensitive ATM-deficient models, it is necessary to inhibit ATR continuously to give tumour stabilisation, which can be achieved through repeat daily of AZD6738 over several weeks. Co-dosing AZD6738 in combination with olaparib or carboplatin gives best efficacy compared to sequential dosing and PK cover over the first 48-72 hours is necessary to give tumour regressions. The models predict that extending the duration of ATR cover, achieved through repeat daily dosing, further increases efficacy. These pre-clinical dose-schedules were compared to human free plasma AZD6738 PK data and predicted efficacious exposures found to be clinically achievable.

Conclusions: Together these data further support the clinical evaluation of AZD6738 and suggest optimal dosing schedules for ATR inhibitors.

Citation Format: Alan Y. Lau, James Yates, Zena Wilson, Lucy A. Young, Adina M. Hughes, Alienor Berges, Amy Cheung, Rajesh Odedra, Elaine Brown, Mark J. O'Connor, Simon Hollingsworth. ATR inhibitor AZD6738 as monotherapy and in combination with olaparib or chemotherapy: defining pre-clinical dose-schedules and efficacy modelling [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2494. doi:10.1158/1538-7445.AM2017-2494

An attention and interpretation bias for illness-specific information in chronic fatigue syndrome

BACKGROUND

Studies have shown that specific cognitions and behaviours play a role in maintaining chronic fatigue syndrome (CFS). However, little research has investigated illness-specific cognitive processing in CFS. This study investigated whether CFS participants had an attentional bias for CFS-related stimuli and a tendency to interpret ambiguous information in a somatic way. It also determined whether cognitive processing biases were associated with co-morbidity, attentional control or self-reported unhelpful cognitions and behaviours.

METHOD

A total of 52 CFS and 51 healthy participants completed self-report measures of symptoms, disability, mood, cognitions and behaviours. Participants also completed three experimental tasks, two designed specifically to tap into CFS salient cognitions: (i) visual-probe task measuring attentional bias to illness (somatic symptoms and disability) v. neutral words; (ii) interpretive bias task measuring positive v. somatic interpretations of ambiguous information; and (iii) the Attention Network Test measuring general attentional control.

RESULTS

Compared with controls, CFS participants showed a significant attentional bias for fatigue-related words and were significantly more likely to interpret ambiguous information in a somatic way, controlling for depression and anxiety. CFS participants had significantly poorer attentional control than healthy individuals. Attention and interpretation biases were associated with fear/avoidance beliefs. Somatic interpretations were also associated with all-or-nothing behaviour and catastrophizing.

CONCLUSIONS

People with CFS have illness-specific biases which may play a part in maintaining symptoms by reinforcing unhelpful illness beliefs and behaviours. Enhancing adaptive processing, such as positive interpretation biases and more flexible attention allocation, may provide beneficial intervention targets.

Comparison of arthroscopic and MRI findings of osteochondral damage in knees

Magnetic resonance imaging (MRI) scans are widely used in the assessment of knees, often prior to arthroscopic procedures. The reporting of osteochondral damage on MRI scans can be variable. The correlation between MRI reports of osteochondral damage and that found at arthroscopy is often inconsistent. A retrospective case-note review of a single-surgeon series of 175 arthroscopic procedures was performed. Eighty-three patients were included in the study. The remainder were excluded if an MRI scan had not been performed or had been performed more than 3-months before surgery. The condition of the articular cartilage demonstrated by MRI was compared to that found at arthroscopy. Data was analysed for presence and extent of osteochondral damage. Comparison between MRI and arthroscopy findings showed high specificity (90%) and negative predictive values (89%) for osteochondral damage but low sensitivity (46%). Cohen's kappa values < 0.2 revealed very poor correlation for the extent of damage. This study demonstrates MRI as a good identifier of osteochondral damage but an unreliable descriptor for such change.

Structure-activity relationship of a series of non peptidic RGD integrin antagonists targeting α5β1: part 1

Potent antagonists of the integrin α(5)β(1), which are RGD mimetics built from tyrosine are described. This letter describes the optimization of in vitro potency obtained by variation of two parts of the molecule, the basic group and the linker between the basic group and the phenyl central core.

Structure-activity relationship of a series of non peptidic RGD integrin antagonists targeting α5β1: part 2

Potent antagonists of the integrin α(5)β(1), which are RGD mimetics built from tyrosine are described. This paper describes the optimization of in vitro potency obtained by variation of two parts of the molecule, the central aromatic core and the amide moiety.

Design & control of a 3D stroke rehabilitation platform

An upper limb stroke rehabilitation system is developed which combines electrical stimulation with mechanical arm support, to assist patients performing 3D reaching tasks in a virtual reality environment. The Stimulation Assistance through Iterative Learning (SAIL) platform applies electrical stimulation to two muscles in the arm using model-based control schemes which learn from previous trials of the task. This results in accurate movement which maximises the therapeutic effect of treatment. The principal components of the system are described and experimental results confirm its efficacy for clinical use in upper limb stroke rehabilitation.

Epstein-Barr virus and multiple sclerosis

This review of the considerable evidence linking Epstein-Barr virus (EBV) infection to risk and disease progression in multiple sclerosis (MS) builds on the background to the virus and its interactions with the human host available in the online supplement (see supplement, available online only). The evidence for a similarity in the geographic patterns of occurrence of MS and EBV infection (with infectious mononucleosis or EBV specific serology used as surrogate markers), when reviewed critically, is very limited. There is strong evidence however that people with MS are more likely to report a past history of infectious mononucleosis (thought to represent initial EBV infection at an older age), and higher titres of EBV specific antibodies are associated with an increased risk of developing MS. Elevated levels of the latter are apparent many years before MS onset (compared with non-MS controls) and there is a dose-response relationship between MS risk and antibody titre, with antibodies to the EBV nuclear antigen-1 particularly important. The evidence in relation to EBV DNA load in blood or CSF is conflicting, as is that in relation to T cell responses to EBV. Several hypotheses that have been proposed to explain the links between EBV and MS risk are reviewed and gaps requiring further research are identified.

Expanded dog leukocyte antigen (DLA) single nucleotide polymorphism (SNP) genotyping reveals spurious class II associations

The dog leukocyte antigen (DLA) system contains many of the functional genes of the immune system, thereby making it a candidate region for involvement in immune-mediated disorders. A number of studies have identified associations between specific DLA class II haplotypes and canine immune hemolytic anemia, thyroiditis, immune polyarthritis, type I diabetes mellitus, hypoadrenocorticism, systemic lupus erythematosus-related disease complex, necrotizing meningoencephalitis (NME) and anal furunculosis. These studies have relied on sequencing approximately 300 bases of exon 2 of each of the DLA class II genes: DLA-DRB1, DLA-DQA1 and DLA-DQB1. In the present study, an association (odds ratio=4.29) was identified by this method between Weimaraner dogs with hypertrophic osteodystrophy (HOD) and DLA-DRB1∗01501. To fine map the association with HOD, a genotyping assay of 126 coding single nucleotide polymorphisms (SNPs) from across the entire DLA, spanning a region of 2.5 Mb (3,320,000-5,830,000) on CFA12, was developed and tested on Weimaraners with HOD, as well as two additional breeds with diseases associated with DLA class II: Nova Scotia duck tolling retrievers with hypoadrenocorticism and Pug dogs with NME. No significant associations were found between Weimaraners with HOD or Nova Scotia duck tolling retrievers with hypoadrenocorticism and SNPs spanning the DLA region. In contrast, significant associations were found with NME in Pug dogs, although the associated region extended beyond the class II genes. By including a larger number of genes from a larger genomic region, a SNP genotyping assay was generated that provides coverage of the extended DLA region and may be useful in identifying and fine mapping DLA associations in dogs.

Feasibility of iterative learning control mediated by functional electrical stimulation for reaching after stroke

BACKGROUND

An inability to perform tasks involving reaching is a common problem following stroke. Evidence supports the use of robotic therapy and functional electrical stimulation (FES) to reduce upper limb impairments, but current systems may not encourage maximal voluntary contribution from the participant because assistance is not responsive to performance.

OBJECTIVE

This study aimed to investigate whether iterative learning control (ILC) mediated by FES is a feasible intervention in upper limb stroke rehabilitation.

METHODS

Five hemiparetic participants with reduced upper limb function who were at least 6 months poststroke were recruited from the community. No participants withdrew.

INTERVENTION

Participants undertook supported tracking tasks using 27 different trajectories augmented by responsive FES to their triceps brachii muscle, with their hand movement constrained in a 2-dimensional plane by a robot. Eighteen 1-hour treatment sessions were used with 2 participants receiving an additional 7 treatment sessions.

OUTCOME MEASURES

The primary functional outcome measure was the Action Research Arm Test (ARAT). Impairment measures included the upper limb Fugl-Meyer Assessment (FMA), tests of motor control (tracking accuracy), and isometric force.

RESULTS

Compliance was excellent and there were no adverse events. Statistically significant improvements were measured (P <or= .05) in FMA motor score, unassisted tracking for 3 out of 4 trajectories, and in isometric force over 5 out of 6 directions. Changes in ARAT were not statistically significant.

CONCLUSION

This study has demonstrated the feasibility of using ILC mediated by FES for upper limb stroke rehabilitation.

Occupational exposure to power frequency magnetic fields and risk of non-Hodgkin lymphoma

OBJECTIVES

To investigate the risk of non-Hodgkin lymphoma (NHL) using a job-exposure matrix (JEM) to assess exposure to occupational magnetic fields at the power frequencies of 50/60 Hz.

METHODS

The study population consisted of 694 cases of NHL, first diagnosed between 1 January 2000 and 31 August 2001, and 694 controls from two regions in Australia, matched by age, sex and region of residence. A detailed occupational history was given by each subject. Exposure to power frequency magnetic fields was estimated using a population-based JEM which was specifically developed in the United States to assess occupational magnetic field exposure. The cumulative exposure distribution was divided into quartiles and adjusted odds ratios were calculated using the lowest quartile as the referent group.

RESULTS

For the total work history, the odds ratio (OR) for workers in the upper quartile of exposure was 1.48 (95% CI 1.02 to 2.16) compared to the referent (p value for trend was 0.006). When the exposure was lagged by 5 years the OR was 1.59 (95% CI 1.07 to 2.36) (p value for trend was 0.003). Adjusting for other occupational exposures did not significantly alter the results.

CONCLUSIONS

These findings provide weak support for the hypothesis that occupational exposure to 50/60 Hz magnetic fields increases the risk of NHL.

Factors determining the optimal body site and method for obtaining punch biopsies of human skin as a tissue in which to assess pharmacodynamic and pharmacokinetic endpoints in drug development studies

There are potential advantages to detecting pharmacodynamic (PD) and pharmacokinetic (PK) endpoints in a tissue-based compartment such as the skin during the development of molecularly targeted drugs. We explored regional differences between inner arm, inner thigh, lower back and buttocks in 12 healthy male Caucasian volunteers in the tolerability of skin biopsy procedures; the Ki67 proliferation index; the frequency of detecting hair follicles and sweat glands; and the percentage of melanocytes. We also explored the amounts of tissue and protein obtained, and two separate methods of splitting biopsies for processing in mutually exclusive media. Biopsies from all body sites were well tolerated. The subjective ranking order was inner arm > buttocks = back > thigh. There were no statistically significant differences in the Ki67 labelling index (P > 0.05). The frequency of detecting sweat glands was the same in all body sites, but the frequency of detecting hair follicles was higher in back and buttock, compared to arm and thigh. The percentage of melanocytes was significantly lower in the buttocks compared to the back and thigh (P < 0.05), but not compared to the arm (P = 0.07). A 4-mm punch biopsy yielded a mean of 16.8 mg of tissue (range: 9-28 mg) and 160 microg of protein (range: 80-270 microg). In vivo sample splitting, by following a 2-mm punch with a 4-mm overpunch, had a shorter time from devascularisation to immersion into processing medium than ex vivo dissection of a 4-mm sample, which may be of importance to the assessment of labile endpoints. We conclude that multiple punch biopsies of the skin are feasible, with the buttocks representing the studied body site with the optimal balance between tolerability, hair follicle density and melanocyte density for obtaining tissue in which to assess PD and PK endpoints during drug development studies.

Occupational exposure to pesticides and risk of non-Hodgkin's lymphoma

Pesticide exposure may be a risk factor for non-Hodgkin's lymphoma, but it is not certain which types of pesticides are involved. A population-based case-control study was undertaken in 2000-2001 using detailed methods of assessing occupational pesticide exposure. Cases with incident non-Hodgkin's lymphoma in two Australian states (n = 694) and controls (n = 694) were chosen from Australian electoral rolls. Logistic regression was used to estimate the risks of non-Hodgkin's lymphoma associated with exposure to subgroups of pesticides after adjustment for age, sex, ethnic origin, and residence. Approximately 10% of cases and controls had incurred pesticide exposure. Substantial exposure to any pesticide was associated with a trebling of the risk of non-Hodgkin's lymphoma (odds ratio = 3.09, 95% confidence interval: 1.42, 6.70). Subjects with substantial exposure to organochlorines, organophosphates, and "other pesticides" (all other pesticides excluding herbicides) and herbicides other than phenoxy herbicides had similarly increased risks, although the increase was statistically significant only for "other pesticides." None of the exposure metrics (probability, level, frequency, duration, or years of exposure) were associated with non-Hodgkin's lymphoma. Analyses of the major World Health Organization subtypes of non-Hodgkin's lymphoma suggested a stronger effect for follicular lymphoma. These increases in risk of non-Hodgkin's lymphoma with substantial occupational pesticide exposure are consistent with previous work.

Specific inhibition of the endothelin A receptor with ZD4054: clinical and pre-clinical evidence

Activation of the endothelin A receptor (ET(A)) by endothelin-1 (ET-1) mediates events that regulate mitogenesis, apoptosis, angiogenesis and metastasis in tumours. Specific blockade of ET(A) may have anticancer effects, while retaining beneficial endothelin B receptor (ET(B))-mediated effects such as apoptosis and clearance of ET-1. ZD4054 is an orally active, specific ET(A) antagonist in clinical development. In receptor-binding studies, ZD4054 specifically bound to ET(A) with high affinity; no binding was detected at ET(B). In a randomised placebo-controlled trial in eight healthy volunteers, a single oral dose of ZD4054 reduced forearm vasoconstriction in response to brachial artery infusion of ET-1, thus providing clinical evidence of ET(A) blockade. ET(B) blockade was assessed in an ascending, single-dose, placebo-controlled trial in 28 volunteers. For all doses of ZD4054, mean plasma ET-1 concentrations measured at 4 and 24 h were within the placebo reference range (a rise in ET-1 would indicate ET(B) blockade) and there was no evidence of dose-related changes. These data confirm the specificity of ZD4054 for ET(A), with no activity at ET(B) in a clinical or preclinical setting. As a result of this specificity, ZD4054 has the potential to block multiple ET(A)-induced pathological processes, while allowing beneficial ET(B)-mediated processes to continue, which may, in turn, lead to an effective cancer therapy.

Assessing proliferation, cell-cycle arrest and apoptotic end points in human buccal punch biopsies for use as pharmacodynamic biomarkers in drug development

Easily accessible normal tissues expressing the same molecular site(s) of drug action as malignant tissue offer an enhanced potential for early proof of anticancer drug mechanism and estimation of the biologically effective dose. Studies were undertaken in healthy male volunteers to assess the tolerability of single and multiple (four in 24 h) 3 mm punch biopsies of the buccal mucosa, and to determine the feasibility of detecting and quantifying a range of proliferation, cell-cycle arrest and apoptosis markers by immunohistochemistry (IHC) for use as potential pharmacodynamic (PD) end points. The biopsy procedure was well tolerated with 100% of volunteers stating that they would undergo single (n=10) and multiple (n=12) biopsies again. Total retinoblastoma protein (pRb), phosphorylated pRb (phospho-pRb), total p27, phosphorylated p27 (phospho-p27), phosphorylated-histone H3 (phospho-HH3), p21, p53, Cyclin A, Cyclin E, Ki67 all produced good signal detection, but M30, cleaved caspase 3 and terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labelling did not. Total pRb, phospho-pRb, total p27 and phospho-p27 were quantified further in a multiple biopsy study to allow components of variability to be addressed to inform future sizing decisions on intervention studies. Neither site of biopsy within the oral cavity, nor the nominal time of biopsy had any significant impact on any of the four markers expression levels. Inter- and intrasubject coefficients of variation (CVs) that could be used to size future intervention studies for pRb, phospho-pRb, total p27 and phospho-p27 were 14, 19, 18 and 16%; and 18, 29, 25 and 19%, respectively. In conclusion, quantitation of such markers in 3 mm buccal punch biopsies would be suitable to explore as PD end points within intervention studies of drugs acting on these pathways.

Plucked human hair as a tissue in which to assess pharmacodynamic end points during drug development studies

We have demonstrated the feasibility of detecting and quantifying six cell-cycle-related nuclear markers (Ki67, pRb, p27, phospho-p27 (phosphorylated p27), phospho-pRb (phosphorylated pRb), phospho-HH3 (phosphorylated histone H3)) in plucked human scalp and eyebrow hair. Estimates of the proportion of plucked hairs that are lost or damaged during processing plus the intra- and intersubject variability of each nuclear marker with these techniques are provided to inform sizing decisions for intervention studies with drugs potentially impacting on these markers in the future.

Recurrent miscarriage and long-term thrombosis risk: a case–control study

BACKGROUND

Recurrent miscarriage has been associated with antiphospholipid syndrome (APS) and other prothombotic conditions. We tested the hypothesis that women diagnosed as having APS as an aetiological factor for their miscarriages were at higher risk of thrombosis than those with idiopathic recurrent miscarriage.

METHODS

A retrospective case-control study was performed using validated questionnaires. A total of 141 women with recurrent miscarriage and APS alone were matched with 141 women with idiopathic recurrent miscarriage for age, number and type of pregnancy loss and number of years of follow-up. A subgroup of eight women included those who initially presented with recurrent miscarriage, thrombosis and APS.

RESULTS

The mean length of follow-up was 7.3 years and response rate 74%. The incidence of thrombosis was similar in the recurrent miscarriage and APS women (6/1000 women-years) and in the idiopathic recurrent miscarriage women (2/1000 women-years) (P = 0.18). All eight women who presented with recurrent miscarriage, APS and thrombosis reported further thrombotic events.

CONCLUSIONS

Both idiopathic and APS-associated recurrent miscarriage were associated with a similar long-term risk of thrombosis.

An investigation of components of variance and tachyphylaxis in a placebo-controlled intravenous tyramine study

AIMS

To explore inter- and intra-volunteer variability for the dose of intravenous tyramine eliciting a 20 mmHg increase in systolic blood pressure from baseline (TYR20) and to evaluate potential tachyphylaxis.

METHODS

Twelve healthy volunteers received blinded placebo-controlled ascending and descending sequences of intravenous tyramine injections on two separate occasions. The TYR20 was derived by linear interpolation, using three interventions to deal with missing data.

RESULTS

Analysis of covariance (ancova) demonstrated no significant difference in TYR20 between sequences, regardless of the missing data methodology applied. Inter-volunteer variability was 2.4-3.4 times larger than within-volunteer variability. No evidence of tachyphylaxis was seen using either the sign test or generalized additive models.

CONCLUSIONS

Since inter-volunteer variability was greater than intra-volunteer variability, a crossover study design would be a more efficient study design, and the descending sequence of injections could be omitted since tachyphylaxis was not demonstrated.

Use of the WHO lymphoma classification in a population-based epidemiological study

BACKGROUND

Non-Hodgkin's lymphoma (NHL) is pathologically diverse. Epidemiological investigations into its increasing incidence and aetiology require accurate subtype classification.

PATIENTS AND METHODS

Available pathology reports of 717 cases aged from 20 to 74 years in an Australian, population-based epidemiological study of NHL were reviewed by one anatomical pathologist to assign a World Health Organization (WHO) classification category. High or low confidence was assigned to the diagnosis of NHL, cell phenotype and WHO category and reasons given for low confidence.

RESULTS

The most informative biopsy reports were from open tissue biopsy (79% of cases), tissue core biopsy (8%), cytology (4%) and bone marrow (9%); 8% of cases had inadequate biopsies for diagnostic purposes. Immunohistochemistry or flow cytometry reports were available for 96% of cases, gene rearrangement studies for 6% and cytogenetics for 3%. The reviewer assigned high confidence to the diagnosis of NHL in 93% of cases and also the phenotype in 88%. While a WHO classification could be assigned in 91% of cases, confidence was high in only 57.5%; insufficient immunophenotyping was the commonest reason for low confidence.

CONCLUSIONS

Expert pathology review of a population-based sample of NHL can provide a WHO classification category for most cases. A high level of confidence in the classification, however, would require review of diagnostic material and additional phenotyping.

Assessment of the effect of dextromethorphan and ketamine on the acute nociceptive threshold and wind-up of the second pain response in healthy male volunteers

AIMS

The aim of this study was to assess the efficacy of dextromethorphan and ketamine relative to placebo on the acute nociceptive threshold and wind-up of second pain response in healthy male volunteers.

METHODS

The trial was a randomized, double-blind, placebo-controlled, three period crossover, double dummy design in 12 healthy male volunteers. During each of the three periods (which were separated by a 1 week washout period) each volunteer received either a single oral dose of 0.7 mg kg(-1) dextromethorphan and placebo to ketamine, or placebo to dextromethorphan followed by a single intravenous injection of 0.375 mg kg(-1) ketamine, or placebo to both dextromethorphan and ketamine. The trial did not schedule administration of both ketamine and dextromethorphan together. Acute nociceptive thresholds and wind-up of second pain were measured in the skin of the thenar eminence of the ventral surfaces of the right and left hands, using a SOMEDIC thermotest apparatus, before and at the estimated tmax for dextromethorphan (i.e. 2.15 h). Blood pressure and heart rate were also monitored before dosing and after the dosing regimen.

RESULTS

Neither dextromethorphan nor ketamine had any significant effect on acute nociceptive thresholds on either hand (P>0.05). Moreover, dextromethorphan was without any significant effect (P>0.05) on the wind-up of the second pain response on either hand. The lsmean number of stimuli tolerated vs placebo (95% confidence intervals of the difference in number of stimuli in parentheses) were 15.84 vs 16.48 (-5.52, 4.24) and 11.75 vs 15.25 (-11.89, 4.90) for left- and right-hand, respectively, following dextromethorphan administration. In contrast ketamine produced significant reductions in wind-up to second pain in both the left and right hands (P=0.0002 and 0.0386, respectively). The lsmean numbers of stimuli tolerated vs placebo (95% confidence intervals of the difference in number of stimuli in parentheses) were 28.41 vs 16.48 (6.60, 17.25) and 25.00 vs 15.25 (0.58, 18.93) for left- and right-hand, respectively.

CONCLUSIONS

Wind-up of second pain induced by noxious heat is sensitive to intervention by ketamine, which is known to block the NMDA receptor. These data infer that the wind-up phenomenon evoked by noxious heat involves the activation of NMDA receptors. This volunteer model of pain may have utility in the evaluation of agents that modulate their antinociceptive actions via NMDA mechanisms.

Associations of CCR5, CCR2, and stromal cell-derived factor 1 genotypes with human immunodeficiency virus disease progression in patients receiving nucleoside therapy

Genotype data for CCR5, CCR2, and stromal cell-derived factor 1 (SDF-1) were obtained from 354 human immunodeficiency virus type 1 (HIV-1)-positive subjects who were being treated with nucleosides. Associations with HIV-1 load, HIV syncytium-inducing (SI) phenotype, CD4 cell count, and disease progression were analyzed. No differences in HIV-1 load or CD4 cell count were observed between wild type (+) and variant genotypes. Changes from non-SI to SI viral phenotype were more frequent in heterozygotes with a 32-bp deletion (Delta32) in the CCR5 gene than in + homozygotes (40% vs. 7%; P=.01). In a multivariate analysis, heterozygous CCR5 Delta32 was associated with reduced hazard of progression (hazard ratio, 0.32; P=.02). Subjects homozygous for the SDF-1 3'A variant had more-rapid disease progression (P=.008). The SDF-1 homozygous 3'A variant was related to more-rapid disease progression, and CCR5 Delta32 was associated with reduced rates of hazard for disease progression in nucleoside-treated subjects.

Evaluation of a (pilot) stage-tailored brief smoking cessation intervention among hospital patients presenting to a hospital pre-admission clinic

Despite the significant benefits of advising all smokers to quit, hospital patients who smoke do not systematically receive this advice. This study sought to determine the prevalence of smoking, attitudes of patients towards not smoking while in hospital, and the feasibility and effectiveness of a brief smoking cessation intervention in a pre-admission clinic context. Over 230 smokers received a brief smoking cessation intervention, while a control group (n = 114) received only a free Quit Kit. The age-standardised smoking prevalence was 19%; a further 3% of patients were recent quitters. Most smokers do not expect or experience problems with not smoking while in hospital. Brief smoking cessation advice tailored to stage-of-change by a health worker in a hospital pre-admission clinic significantly increased the quit rates for females.

Diurnal variation in the quantitative EEG in healthy adult volunteers

AIMS

To define the change in power in standard waveband frequencies of quantitative cortical electroencephalogram (EEG) data over a 24 h period, in a drug free representative healthy volunteer population.

METHODS

This was an open, non randomised study in which 18 volunteers (9 male and 9 female) were studied on 1 study day, over a 24 h period. Volunteers had a cortical EEG recording taken at 0, 2, 4, 6, 8, 10, 12, 16 and 24 h. Each recording lasted for 6 min (3 min eyes open, 3 min eyes closed). All EEG recordings were taken in a quietened ward environment with the curtains drawn round the bed and the volunteer supine. During the 3 min eyes open, volunteers were asked to look at a red circle on a screen at the foot of the bed, and refrain from talking.

RESULTS

Plots produced of geometric mean power by time of the standard wave band frequencies gave some indication of a circadian rhythm over the 24 h period for theta (4. 75-6.75 Hz), alpha1 (7.0-9.5 Hz) and beta1 (12.75-18.50 Hz) wavebands. Mixed models were fitted to both the eyes open and eyes closed data which confirmed a change in mean waveband power with time with statistical significance at the conventional 5% level (P < 0.05).

CONCLUSIONS

These data indicate the presence of a diurnal variation in the cortical quantitative EEG. They support the use of a placebo control group when designing clinical trials which utilize quantitative EEG to screen for central nervous system (CNS) activity of pharmaceutical agents, to control for the confounding variable of time of day at which the EEG recordings were made.

A community study of lower urinary tract symptoms in older men in Sydney, Australia

BACKGROUND

The aim of the present paper was to determine the prevalence, bother attributable to and self-reported management of uncomplicated lower urinary tract symptoms (LUTS) in men aged 40-80 years in Sydney, Australia.

METHODS

A total of 340 randomly selected men aged 40-80 years (65% response rate) participated in a community-based study (computer-assisted telephone survey).

RESULTS

Lower urinary tract symptoms are common: 54% of men needed to wake up at least once at night to urinate; 47% indicated they had terminal dribbling 'sometimes' or 'frequently'; 30% experienced urgency although few (4%) had urge incontinence; 21% experienced hesitancy; and 19% could retain urine in their bladder during the day for no more than 2 hours. Urinary symptoms correlated poorly with self-rated bother and there was no increase in age-specific prevalence of bothersome symptoms with increasing age. Only 37 (26%) men inconvenienced by urinary symptoms had seen a general practitioner (GP) about these symptoms in the last 5 years: of these, two-thirds had been referred to a urologist and half of these received surgical treatment. Independent predictors of attending a GP were increasing age (adjusted odds ratio (AOR) = 12.3; P = 0.0015); place of birth outside Australia (AOR = 3.8; P = 0.0036) and anxiety about prostate cancer (AOR = 2.6; P = 0.0318), but not the degree of worry due to urinary symptoms.

CONCLUSION

Lower urinary tract symptoms are common in men, but their experiences of bother correlate weakly with symptoms and do not appear to influence referral and treatment. Public and professional campaigns might increase wider understanding of the benefits of surgery for bothersome symptoms, not symptoms per se.

Community study of uncomplicated lower urinary tract symptoms among male Italien immigrants in Sydney, Australia

OBJECTIVE

To determine the prevalence, levels of bother and self-reported management of lower urinary tract symptoms (LUTS) in Italian-born men aged 40-80 years.

METHOD

305 randomly selected men aged 40-80 years (72% response rate) participated in a community-based study (computer-assisted telephone survey) in early 1997 in Sydney, Australia.

RESULTS

LUTS are common: 41% of men needed to wake up at least once at night to urinate; 35% indicated they had terminal dribbling 'sometimes' or 'frequently'; 31% experienced urgency although few (3%) had urge incontinence; 19% could retain urine in their bladder during the day for no more than 2 h, and 19% experienced hesitancy. Urinary symptoms correlated moderately/poorly with self-rated bother. The prevalence of bothersome frequency and urgency was significantly age-related. Only half (n = 49, 52%) of the men bothered by urinary symptoms had seen a general practitioner (GP) about these symptoms in the last 5 years: of these three quarters had been referred to a urologist and half of these had received surgical treatment. Anxiety about prostate cancer, but not the degree of bother from urinary symptoms, independently predicted attendance at a GP (adjusted odds ratio 6.4, p = 0.006).

CONCLUSIONS

Although LUTS are common in Italian-born men, their experiences of bother do not correlate well with symptoms and do not appear to influence referral and treatment. Education is needed to improve men's understanding of the importance of 'bother' as an indicator for urological surgery.

Smoking: rates and attitudes among nursing staff in central Sydney

The objectives of this study were to determine the prevalence and predictors of smoking and attitudes to smoking-related issues among nurses employed by the Central Sydney Area Health Service in Sydney, Australia. A self-administered questionnaire, was distributed via the internal mail system of the Central Sydney Area Health Service in November 1997 to 610 randomly selected nursing staff. Twenty-one per cent (n = 127) of respondents smoked. Smokers were significantly younger than non-smokers and were more likely to speak mainly English at home. There were clear differences between smokers and non-smokers in response to all attitude statements. Interventions specifically directed at nurses who smoke to assist them to stop and maintain cessation are indicated. Future health service workplace tobacco control programmes should address deficits in knowledge about the health effects of passive smoking, should raise awareness among nurses who smoke about their potential to affect the behaviours of others through modelling, and should provide all nurses with the skills required to be smoking educators and advocates for tobacco control.

Electroencephalographic and psychomotor effects of chlorpromazine and risperidone relative to placebo in normal healthy volunteers

AIMS

To investigate the effects of single oral doses of chlorpromazine (50 mg) and risperidone (2 mg) relative to placebo on topographical electroencephalometry (CATEEMTM ) and psychomotor tests in 12 healthy male volunteers.

METHODS

A double-blind, placebo-controlled, three-way crossover design using a double dummy blinding technique was utilized. Chlorpromazine was selected as representative of the 'typical' neuroleptics, being also highly sedative. Risperidone has been suggested as representative of the newer 'atypical' neuroleptics and is claimed to be only minimally sedative. Volunteers were dosed on 3 separate days with a minimum of 7 days interval between trial days. On each trial day volunteers were dosed twice. Dose 1 consisting of either chlorpromazine 50 mg or placebo to chlorpromazine, and dose 2 either risperidone 2 mg or placebo to risperidone. The volunteers were randomized so that each received either chlorpromazine or risperidone (or neither), but not both on an individual trial day. A 17 electrode quantitative topographical electroencephalograph (EEG) recording was taken for each volunteer before and after each dosing period. Seven psychomotor function tests were used to determine the effects of each treatment on psychomotor performance.

RESULTS

The data confirm the cited reports of sedation following single oral doses of chlorpromazine 50 mg. However, 7 of the 12 volunteers dosed with risperidone 2 mg also reported drowsiness/lethargy which was of greater severity and duration than 5 of the 12 volunteers who reported somnolence following dosing with chlorpromazine 50 mg. Objective assessment of psychomotor impairment using a short battery of psychomotor function tests mirrored the subjective reports of somnolence in that the impairment in volunteers dosed with risperidone 2 mg was greater in extent and magnitude than in volunteers dosed with chlorpromazine 50 mg. With respect to the cortical quantitative electroencephalogram, both chlorpromazine (50 mg) and risperidone (2 mg) increased power (4.75-6.75 Hz) in keeping with cited effects of other neuroleptics on the quantitative EEG. In addition, there was a statistically significant increase (P<0.05) in alpha1 (7.0-9.5 Hz) and beta1 (12.75-18.5 Hz) wavebands in volunteers dosed with risperidone 2 mg. Furthermore, based on estimates of variability, we propose that a 3 min eyes open and 3 min eyes closed quantitative EEG recording is sufficient to maintain adequate power for this technique, whilst allowing its application to early volunteer trials of novel neuroleptic agents.

CONCLUSIONS

This study demonstrates that quantitative EEG can be utilized in the profiling of neuroleptic agents, and could be readily applied to the early profiling of novel neuroleptics in limited numbers of volunteers, early in drug development. The chosen battery of psychomotor tests has clearly demonstrable sensitivity to the quantification of the subjective reports of somnolence secondary to both chlorpromazine and risperidone.

Effects of zolmitriptan (Zomig) on central serotonergic neurotransmission as assessed by active oddball auditory event-related potentials in volunteers without migraine

In this randomized, double-blind, three-period crossover trial, 24 healthy volunteers without migraine received zolmitriptan 5 mg, dexfenfluramine 15 mg or placebo orally. At 2, 6, and 24 h postdose, auditory stimuli of 1000 Hz (nontarget tone) and 2000 Hz (target tone) were randomly and binaurally presented in an active oddball paradigm (4:1 ratio). Cortical auditory evoked responses were recorded for 500 msec poststimulus. Plasma concentrations of zolmitriptan and a 17-lead quantitative EEG were assessed at the same timepoints. Relative to placebo, zolmitriptan reduced the maximum absolute amplitude, amplitude difference (from nontarget tone noise) and area under the curve of the cortical auditory target tone event-related potential (P300 ERP). The most dramatic effect of zolmitriptan was to diminish the point estimate of noise during the 200-400 msec poststimulus epoch. The effect of zolmitriptan appeared concentration dependent. The latency of the P300 ERP was unaffected by zolmitriptan and there was no clinically significant effect on the EEG. Modification by zolmitriptan of the cortical electrical activity evoked by auditory stimuli confirms a central action of this drug in humans, which appears to affect cortical information processing without global alteration of the quantitative EEG.

Effects of the antimigraine compound zolmitriptan ('Zomig') on psychomotor performance alone and in combination with diazepam in healthy volunteers

Zolmitriptan (Zomig) is a 5HT1B/1D agonist which has the ability to cross the intact blood-brain barrier to access central as well as peripheral receptors. Because of the potential for central nervous system side effects, this randomized, double-blind, placebo-controlled, 6-period crossover study evaluated the effects of 2.5 and 5 mg doses of zolmitriptan on psychomotor performance and investigated any pharmacodynamic or pharmacokinetic interaction with diazepam. Twelve healthy volunteers received the following "treatments" as single doses: zolmitriptan 2.5 mg, zolmitriptan 5 mg, diazepam 10 mg, zolmitriptan 2.5 mg + diazepam 10 mg, zolmitriptan 5 mg + diazepam 10 mg and placebo. Pre-dose and at 1, 4, 8, and 24 h post-dose, the following validated battery of psychomotor tests was performed: Bond-Lader visual analogue scales (calmness, contentedness, and alertness factors), critical flicker fusion test, choice reaction time (recognition, motor, and total reaction times), finger-tapping test, number cancellation test and digit symbol substitution test. Plasma concentrations of zolmitriptan, its active metabolite, and diazepam and its active metabolites were measured at the same timepoints. Zolmitriptan 2.5 and 5 mg had no effect on psychomotor function when given alone. In contrast, diazepam 10 mg had profound effects, consistent with its sedative properties, but there was no synergism on concomitant administration of either dose of zolmitriptan. Plasma concentrations of zolmitriptan, diazepam, and their respective active metabolites were similar when the two drugs were given alone or in combination.

Local implementation of national guidelines on lower urinary tract symptoms: what do general practitioners in Sydney, Australia suggest will work?

OBJECTIVES

Systematic reviews demonstrate that local initiatives are vital to implement nationally developed clinical practice guidelines. Evidence-based guidelines on the management of lower urinary tract symptoms in men were launched by the National Health and Medical Research Council in Sydney in April 1997. A study was conducted through interviews to establish patterns of care in the catchment area before the guidelines were implemented and general practitioners were surveyed in order to ascertain the most useful strategies for local implementation.

DESIGN

A four-page questionnaire asked respondents to rate nine items about guideline dissemination; six items relating to the marketing of the guidelines and 15 implementation strategics: conventional educational activities (six); innovative educational strategies (four); quality improvement approaches (two) and patient-based approaches (three).

SETTING

Sydney, Australia.

STUDY PARTICIPANTS

Eighty-three randomly selected general practitioners (50 males; 33 females).

RESULTS

Eighty-three out of 108 surveys were returned (77%). Respondents placed high value upon endorsement by eminent individuals and organizations other than the organization developing the guidelines; this was likely to gain their initial attention. One hundred per cent of respondents would be encouraged to use the guidelines if they were promoted as improving quality of care. Implementation strategies preferred by respondents included small group continuing education with a urologist and a general practitioner as a facilitator, lectures and patient education materials. Internet access, interactive computer systems, academic detailing' and distance education modules were of least interest.

CONCLUSIONS

Our method is feasible as a first step in planning local dissemination and implementation for national guidelines. While useful in identifying preferred strategies, its longer-term predictive validity for improving patient outcomes through better guideline implementation needs to be established.

Men's estimates of prostate cancer risk and self-reported rates of screening

OBJECTIVE

To determine rates of prostate cancer screening and predictors of men's participation in this screening in the light of national recommendations against prostate cancer screening

DESIGN

Community-based study (computer-assisted telephone survey).

SETTING

Central Sydney Area Health Service.

PARTICIPANTS

Randomly selected men aged 40-80 years.

RESULTS

340 men participated (65% response rate). While the true lifetime (0-74 years) risk of developing or dying from prostate cancer is reported to be one in 18 (6%) and one in 65 (1.5%), respectively, 37% of respondents thought that at least one in five men (20%) would develop prostate cancer before the age of 75 years and 11% that one in five (20%) would die from it. Twenty-two per cent of men aged 50 years or over had been screened for prostate cancer within the previous 12 months. Ever worrying about prostate cancer and bothersome urinary symptoms independently predicted the probability of screening within the previous year. Sociodemographic characteristics such as age, occupation and country of birth were not associated with screening.

CONCLUSIONS

Public health initiatives to discourage prostate cancer screening should focus particularly on men with bothersome urinary symptoms and those who worry about prostate cancer. Accurate information about the low risks of dying from prostate cancer needs to be communicated, and the speculative nature of current evidence in support of screening as a means of reducing this risk should be emphasised.

Increased alkaline phosphatase isoforms in autoimmune diseases

We found significant increases in ALP and ALP isoform band 10 in the serum of patients with early insulin-dependent diabetes, rheumatoid arthritis, and in those with multiple sclerosis during periods of disease exacerbation as compared with healthy controls. The ALP isoforms were assayed by isoelectric focusing. Our data suggest that the increase in ALP and ALP-10 closely reflects the abnormal activation of T lymphocytes that is common in autoimmune diseases, and that the source of the ALP-10 is activated T lymphocytes. ALP-10 is a sensitive but nonspecific marker of an active autoimmune process and appears to have the ability to detect abnormal T-cell activation. ALP-10 may be a useful test in the screening for autoimmune disorders.

Depression and HIV. A nursing perspective on a complex relationship

This article (1) addresses current perspectives on depression as a psychobiologic condition, which in the case of major depression constitutes a bona fide disease state, (2) explores the complex relationship between HIV and depressive illness, and (3) addresses how this new knowledge serves to enhance nursing assessment and intervention in these persons diagnosed with HIV disease and concurrent depression. By attaining these three goals, the nursing clinician gains a broader perspective on depression and HIV.

The use of Functional Consequences Theory in acutely confused hospitalized elderly

Acute confusion is a common complication of hospitalization in the elderly that impacts on both the use of health care resources and the functional status of individuals. Providing optimum nursing care for these patients depends on three factors: 1) the nurse's ability to differentiate acute confusion from other common conditions in the hospitalized elderly, chiefly dementia or depression, 2) the nurse's ability to identify factors contributing to this condition, and 3) the implementation of interventions to minimize the effects of these factors on the patient. This article differentiates the clinical features of acute confusion from those of depression and dementia, and discusses the use of the Functional Consequences Theory, developed by Miller (1990), as a framework for nursing assessment and management of care for elderly patients with this condition. The functional consequences theory framework assists the nurse to identify risk factors associated with the development of acute confusion in the hospitalized elderly. Further it guides the development of interventions to minimize the effects of this condition in this population. The use of this framework in the clinical setting is illustrated through a case study.

Parents' perceptions of caring for an infant or toddler with diabetes

Although the incidence rate of diabetes in children under the age of 3 years is increasing dramatically, no previous studies provide information about the day-to-day experience of caring for these infants and toddlers. Because a young child with diabetes is dependent on the parent for his/her very existence, the purpose of this phenomenological study was to gain knowledge and understanding of the parents' experiences so that appropriate interventions could be developed and implemented to support parental care for this unique population. Findings revealed three distinct phases in the parents' experiences: the diagnosis and child's hospitalization; adjusting to care at home; and long-term adaptation. Within these phases, parents described inordinate amounts of stress exacerbated by the child's young age and the complex, intrusive nature of diabetes management. On the basis of these findings, implications for practice are discussed.