Comparison of Plan Quality Metrics after Left Anterior Descending Coronary Artery Sparing in VMAT Esophageal Radiotherapy

PURPOSE/OBJECTIVE(S)

Cardiotoxicity is a significant late effect of esophageal radiotherapy (RT). Mean heart dose has been implicated with major adverse cardiac events (MACE) and emerging evidence increases MACE association with left anterior descending (LAD) coronary artery specific dose. This retrospective planning study investigates the dosimetric impact of including the LAD as an OAR-sparing objective for VMAT-based plan optimization in patients previously treated for esophageal cancers.

MATERIALS/METHODS

A retrospective cohort was identified of patients who underwent neoadjuvant RT for esophageal cancers between 2017-2020 without intentional LAD sparing. Treatment planning was performed using Eclipse™ treatment planning system. Doses were calculated using Acuros® XB algorithm or anisotropic analytical algorithm with a 2-2.5mm calculation grid. For each patient, the LAD was delineated and the treated VMAT plan was re-optimized to reduce the dose to the LAD receiving 15 Gy to less than 10%, when possible. Re-plans were performed such that 95% of the PTV received the prescription dose. Institutional constraints were used to minimize the dose to the heart, lung, and spinal cord (Table 1). A paired t-test was used to compare the dose between the original VMAT plan used for treatment (Esophagus Original) against those re-optimized (Esophagus + LAD), with significance of p<0.05.

RESULTS

A total of 19 patients were identified. Of those treated, 12 of 19 original plans (63%) exceeded the LAD constraint (V15<10%) with a mean V15 Gy of 47.1%. Plan re-optimization accounting for the LAD allowed for 66.7% (9/12) of cases to meet LAD V15 constraints. Aside from increased sparing of the mean heart dose, there were no statistically significant impacts on target coverage and OAR doses otherwise, including to that of the lung and spinal cord (Table 1).

CONCLUSION

Accounting for LAD dose in treatment planning may help reduce future MACE risks. LAD dose can be significantly reduced without compromising PTV coverage or having significant effects on other OAR dose sparing.

Exome-wide association study to identify rare variants influencing COVID-19 outcomes: Results from the Host Genetics Initiative

Host genetics is a key determinant of COVID-19 outcomes. Previously, the COVID-19 Host Genetics Initiative genome-wide association study used common variants to identify multiple loci associated with COVID-19 outcomes. However, variants with the largest impact on COVID-19 outcomes are expected to be rare in the population. Hence, studying rare variants may provide additional insights into disease susceptibility and pathogenesis, thereby informing therapeutics development. Here, we combined whole-exome and whole-genome sequencing from 21 cohorts across 12 countries and performed rare variant exome-wide burden analyses for COVID-19 outcomes. In an analysis of 5,085 severe disease cases and 571,737 controls, we observed that carrying a rare deleterious variant in the SARS-CoV-2 sensor toll-like receptor TLR7 (on chromosome X) was associated with a 5.3-fold increase in severe disease (95% CI: 2.75-10.05, p = 5.41x10-7). This association was consistent across sexes. These results further support TLR7 as a genetic determinant of severe disease and suggest that larger studies on rare variants influencing COVID-19 outcomes could provide additional insights.

In vivo coronary artery thrombus imaging with 18F-GP1 PET-CT

Background

Coronary artery thrombus is typically present in type 1 myocardial infarction, but small volumes in the setting of an uncertain culprit lesion may be beyond the detection limit of current imaging modalities.

Purpose

Using a novel glycoprotein IIb/IIIa-receptor radiotracer, 18F-GP1, we investigated whether positron emission tomography-computed tomography (PET-CT) could detect thrombus formation in coronary arteries.

Methods

In a single centre cross-sectional study, patients over 40 years of age with myocardial infarction were recruited after myocardial infarction and underwent underwent CT angiography and 18F-GP1 PET-CT. Stable patients with and without coronary artery disease formed a control cohort. Coronary artery 18F-GP1 uptake was visually assessed and quantified using maximum target-to-background ratios (TBRmax).

Results

Ninety-four (44 post-myocardial infarction and 50 control patients) were included in the cross-sectional analysis. The mean age of the post-myocardial infarction group was 61±9 years, three-quarters were male and two thirds had presented with ST elevation on electrocardiography. 34 (80%) patients post-myocardial infarction, but none of the control patients, demonstrated focal 18F-GP1 uptake in the coronary arteries.

Of 42 vessels with an angiographic culprit lesion, 35 (83%) had 18F-GP1 uptake which was significantly higher than non-culprit vessels (p&lt;0.0001) as well as control vessels (p&lt;0.0001), while non-culprit vessel uptake was similar to control vessel uptake (p=0.567): culprit vessel median TBRmax 1.2 [interquartile range 0.96–1.44], non-culprit vessel TBRmax 0.96 [0.84–1.03] and control vessel TBRmax 0.9 [0.76 to 0.94]. Linear regression models demonstrated univariable associations between coronary 18F-GP1 TBRmax and time from myocardial infarction, male sex and presence of culprit vessel. On multivariable analysis, only culprit vessel status was associated with TBRmax (adjusted R2= 0.22, P&lt;0.001). Based on the Youden's index of the ROC curves, the optimal cut-off of predicting the presence of a culprit vessel was 1.20 with a specificity of 97%, accuracy of 83%, sensitivity (60%) and c-statictic of 0.74.

A patient with ectatic vessel and visual thrombus demonstrated the most intense 18F-GP1 uptake (TBRmax 2.0, highest in the cohort) in the region of heaviest thrombus burden (Figure 2). Extra-coronary uptake was seen in regions of left ventricular thrombus, left atrial appendage thrombus, pulmonary thromboembolism and intramyocardial microvascular obstruction.

Conclusions

18F-GP1 PET-CT is able to detect coronary artery thrombus in culprit lesions following myocardial infarction, as well as extra-coronary thrombotic pathologies that may be important in guiding patient management. 18F-GP1 is highly specific in recognising a culprit lesion from a non-culprit lesion both visually as well as quantitatively.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): British Heart Foundation Figure 1Figure 2

Glycoprotein IIb/IIIa receptor targeted PET/CT imaging: a novel diagnostic tool for detecting bioprosthetic valve thrombosis

Background/Introduction

Bioprosthetic valve thrombosis (BPVT) is an important clinical entity eventually following both bioprosthetic surgical and transcatheter aortic valve replacement. Although dynamic contrast-enhanced 4D-MDCT has improved the diagnosis of BPVT, more sensitive and pathology-specific non-invasive imaging tools are lacking. Recently, the glycoprotein IIb/IIIa receptor targeted, elarofiban-derived PET/CT imaging radiotracer [18F]GP1 has been successfully used for visualization of acute venous and arterial thrombi.

Purpose

We hypothesized that [18F]GP1 PET/CT imaging is suitable to detect BPVT.

Methods

In this proof-of-concept study, patients after bioprosthetic aortic valve replacement with symptomatic, severe hemodynamic valve dysfunction and confirmed hypoattenuated leaflet thickening (HALT) in dynamic 4D-MDCT were offered to participate in compassionate use examinations to undergo PET/CT imaging with the investigational [18F]GP1 PET tracer at baseline and after a 12-week course of therapeutic oral anticoagulation.

Results

This case series reports on three patients after aortic valve replacement. Two patients with symptomatic, obstructive BPVT as confirmed by echocardiography and 4D-MDCT fulfilled specified criteria and underwent [18F]GP1 PET/CT imaging. [18F]GP1 PET/CT clearly distinguished between blood pool activity and thrombotic foci. Clot-to-blood ratios at baseline were 8.2 and 4.5, respectively. A 12-week trial of therapeutic oral anticoagulation was associated with a regression of mean transprosthetic pressure gradient and reversal of HALT. Follow-up 4D-MDCT corroborated thrombus resolution in both patients. Correspondingly, [18F]GP1 PET/CT imaging demonstrated decreased tracer uptake in both patients. Clot-to-blood ratio at follow-up visit decreased to 1.2 and 2.9, respectively. While absent tracer uptake was seen in patient #1, residual tracer uptake was observed in patient #2 suggestive of ongoing platelet aggregation. One asymptomatic SAVR patient was examined with [18F]GP1 PET/CT for a different compassionate use and no thrombotic foci were detected on the leaflets.

Conclusions

[18F]GP1 PET/CT is a novel imaging technique in patients with obstructive BPVT. In a head-to-head comparison we show that [18F]GP1 PET/CT may have incremental diagnostic value over dynamic contrast-enhanced 4D-MDCT alone by detection of sites of ongoing platelet aggregation at the molecular level. [18F]GP1 PET/CT may serve as a novel, highly sensitive tool to overcome some limitations of current diagnostic imaging modalities for detecting BPVT and may prove useful for the monitoring and guidance of therapeutic interventions.

Funding Acknowledgement

Type of funding sources: Other. Main funding source(s): Life Molecular Imaging provided material for [18F]GP1 radiolabeling free of charge as part of an ongoing research collaboration.

A comparison of the physical demands associated with various right-angle direct-current power tools

This work examined the physical demands associated with 4 commercially available direct current right-angle power tools along with their computer controlled fastening strategies. Physical demands were measured via an external instrumented handle that could also control the trigger of each tool. Data revealed that forces recorded by the external handle for each of the 4 tools differed. Independent of Joint-Hardness and Target Torque the Atlas Copco TurboTight® and Cleco Low Torque Reaction fastening strategies, both using a rapid spindle-head rotation strategy, produced the lowest peak and impulse force, respectfully, when compared to the 2 tools that were designed to fasten with a longer duration. This work has shown that short duration fastening strategies provide an ergonomics benefit to the users as it requires less force to operate, such force reduction in previous research has been linked to reduced handle displacement and lower muscle effort.

Physical demands associated with right-angle direct-current power-tools: An evaluation of current technology

The purpose of this work was to evaluate the physical demands associated with three direct current powered right-angle power tool tightening strategies at various fastener-location-orientations, target torques and joint-hardness. Physical demands were measured using surface electromyography, handle force and upper body kinematics. Results identified TurboTight®, a rapid and short duration fastening strategy, to produce lower handle force impulse, less joint angle displacement, and lower EMG magnitudes when compared to the longer duration fastening strategies tested. The reduced magnitudes associated with TurboTight®, independent of fastener-location-orientations, target torques and joint-hardness, indicate a lower physical demand on power tool operators, providing a significant ergonomic benefit when compared to the slower fastening strategies.

91 Mrs Bad Bones: Impact of COVID-19 on Secondary Prevention of Fragility Fractures

Introduction

Management of osteoporosis is an important consideration for neck of femur fracture patients due to the morbidity and mortality it poses, and the significant financial burden to the NHS. Orthogeriatric teams input is invaluable in coordinating secondary fragility fracture prevention. The COVID-19 pandemic resulted in the rapid restructuring of healthcare teams and led to the redeployment of the orthogeriatricians to assist with the influx of medically unwell patients. This study explored the impact COVID-19 had on secondary fragility fracture prevention.

Method

A retrospective audit looking at the prescription of vitamin D/calcium supplements, bone-sparing medications, and DEXA scan requests in consecutive neck of femur fracture patients admitted to a trauma and orthopaedic unit pre- and post- UK lockdown in response to the pandemic. A re-audit was conducted following the implementation of our new mnemonic, “MRS BAD BONES”: Medication Review Rheumatology/Renal Advice Smoking Cessation Blood tests Alcohol limits DEXA scan Bone-sparing medications Orthogeriatric review Nutrition Exercise Supplements.

Results

Data for 50 patients was available in each phase. The orthogeriatric team reviewed 88% of patients pre-lockdown falling to 0% due to redeployment, before recovering to 38% in the post-intervention period. Upon lockdown there was a significant drop in the prescription of vitamin D/calcium supplements from 81.6% to 58.0% (p = 0.0156); of bone-sparing medications from 60.7% to 18.2% (p = 0.0037), and DEXA scan requests from 40.1% to 3.6% (p = 0.0027). Following the implementation of our mnemonic, there was a significant increase in the prescription of vitamin D/calcium supplements to 85.7% (p = 0.0034), bone-sparing medications to 72.4% (p = 0.0002) and DEXA scan requests to 60% (p < 0.0001).

Conclusion

COVID-19 had a major impact on the secondary prevention of fragility fractures in this population. The “MRS BAD BONES” mnemonic significantly improved the management and could be considered for use in a wider setting.

Amniotic fluid index curves in the obese gravida

OBJECTIVE

To determine whether amniotic fluid volume as measured by amniotic fluid index (AFI) is influenced by maternal pre-gestational obesity as measured by body mass index (BMI).

METHODS

This was a retrospective cohort study of pregnant women between 20 and 43 weeks gestation receiving ultrasounds with AFI measurements at Augusta University Medical Center between 2003 and 2017. A subset of 500 charts that met inclusion and exclusion criteria were reviewed to obtain maternal clinical data. The study cohort was subdivided by maternal BMI at initial obstetric visit into three groups: normal weight (18.5 kg/m2-24.9 kg/m2), overweight (25.0 kg/m2-29.9 kg/m2), and obese (≥ 30 kg/m2). Chi-square analysis was used to compare BMI groups in terms of categorical clinical characteristics and outcome variables, and analysis of variance (ANOVA) was used for continuous variables. Mixed effects regression models (MRMs) were used to evaluate AFI throughout gestation separately in each group, and MRM-based analysis of covariance was used to compare AFI throughout gestation among groups. AFI curves were constructed for the 5th, 50th, and 95th percentiles for all study subjects combined and separately for normal weight, overweight, and obese subjects.

RESULTS

Fitted curves relating AFI percentiles to estimated gestational age (EGA) showed statistically significant differences among BMI groups. There was also a significant difference in AFI over gestation across the obesity groups.

CONCLUSION

Fitted curves for AFI throughout pregnancy showed statistically significant differences among BMI groups.

Thrombus formation on bioprosthetic aortic valves

Background

18F-GP1 is a novel radiotracer with a high affinity for the platelet glycoprotein IIb/IIIa receptor. Subclinical bioprosthetic valve thrombus has been postulated as a trigger for accelerated valve degeneration.

Purpose

To determine the feasibility of 18F-GP1 positron-emission tomography-computed tomography (PET-CT) for the detection of subclinical bioprosthetic aortic valve thrombus.

Methods

(i) Explanted degenerated aortic valve prostheses underwent histology and imaging. (ii) In a prospective observational study, patients with bioprosthetic aortic valve replacement (AVR) underwent echocardiography and 18F-GP1 PET-CT. Valves were assessed for hypoattenuating leaflet thickening (HALT), hypo-attenuation affection leaflet motion (HAM) and GP1 uptake.

Results

(i) GP1 correlated with thrombus on explanted valves (Figure). (ii) The first 6 patients (Table) were asymptomatic and had normally functioning surgical bioprostheses on echocardiography. At a median of 166 (range 122–189) days post-AVR, no patients had HALT or HAM on CT. There was avid focal GP1 uptake on the leaflets of all 6 patients which appeared most prominent along the leaflet edges (Figure). Only one patient had focal uptake in the valve frame, remote from the leaflets. In a separate cohort undergoing 18F-GP1 PET-CT for other conditions, there was no uptake on normal, native aortic valves (n=8).

Conclusion

For the first time, we demonstrate that 18F-GP1 PET-CT is a highly sensitive method of assessing platelet activation on bioprosthetic aortic valves. Despite the absence of CT evidence, early thrombus appeared to be a universal finding on recently implanted valve prostheses. The biological and clinical implications of subclinical bioprosthetic aortic valve thrombus have yet to be established.

GP1 uptake in AVR

Funding Acknowledgement

Type of funding source: Foundation. Main funding source(s): British Heart Foundation

Humanin Blocks the Aggregation of Amyloid-β Induced by Acetylcholinesterase, an Effect Abolished in the Presence of IGFBP-3

It is known that the humanin (HN) peptide binding to amyloid-β (Aβ) protects against its cytotoxic effects, while acetylcholinesterase (AChE) binding to Aβ increases its aggregation and cytotoxicity. HN is also known to bind the insulin-like growth factor binding protein-3 (IGFBP-3). Here, we examined the regulation of Aβ conformations by HN, AChE, and IGFBP-3 both in vitro and in the conditioned media from A549 and H1299 lung cancer cells. Our in vitro results showed the following: IGFBP-3 binds HN and blocks it from binding Aβ in the absence or presence of AChE; HN and AChE can simultaneously bind Aβ but not when in the presence of IGFBP-3; HN is unable to reduce the aggregation of Aβ in the presence of IGFBP-3; and HN abolishes the aggregation of Aβ induced by the addition of AChE in the absence of IGFBP-3. In the media, AChE and HN can simultaneously bind Aβ. While both AChE and HN are detected when using 6E10 Aβ antibodies, only AChE is detected when using the Aβ 17-24 antibody 4G8, the anti-oligomer A11, and the anti-amyloid fibril LOC antibodies. No signal was observed for IGFBP-3 with any of the anti-amyloid antibodies used. Exogenously added IGFBP-3 reduced the amount of HN found in a complex when using 6E10 antibodies and correlated with a concomitant increase in the amyloid oligomers. Immunodepletion of HN from the media of the A549 and H1299 cells increased the relative abundance of the oligomer vs the total amount of Aβ, the A11-positive prefibrillar oligomers, and to a lesser extent the LOC-positive fibrillar oligomers, and was also correlated with diminished cell viability and increased apoptosis.

Early Supported Discharge for patients with febrile neutropenia - Experience at a large district hospital in the UK

Neutropenic sepsis can be life threatening, with mortality 2-21%. The heterogeneity of patients referred with "suspected neutropenic sepsis" has led to strategies being developed to risk-stratify patients and identify those with a low risk of septic complications that could be managed in the outpatient setting, such as The Multinational Association for Supportive Care in Cancer score (MASCC). Outcomes for patients referred with suspected neutropenic sepsis were assessed before and after use of MASCC guided early-supported discharge. 50/123 (41%) patients over 24 months were eligible for early-supported discharge. 26/50 patients had same-day discharge, 14 had overnight admission, 8 stayed 2 nights and 2 stayed 3 nights. Patients received on average 2 follow-up telephone consultations. There were 5 readmissions (10%) and no adverse events. In comparison group; 8 patients over 3-months would have been suitable, potentially saving 40 bed-days. This shows MASCC guided early-supported discharge is safe and cost-effective.

A practical method to standardise and optimise the Philips DoseRight 2.0 CT automatic exposure control system

Given the increasing use of computed tomography (CT) in the UK over the last 30 years, it is essential to ensure that all imaging protocols are optimised to keep radiation doses as low as reasonably practicable, consistent with the intended clinical task. However, the complexity of modern CT equipment can make this task difficult to achieve in practice. Recent results of local patient dose audits have shown discrepancies between two Philips CT scanners that use the DoseRight 2.0 automatic exposure control (AEC) system in the 'automatic' mode of operation. The use of this system can result in drifting dose and image quality performance over time as it is designed to evolve based on operator technique. The purpose of this study was to develop a practical technique for configuring examination protocols on four CT scanners that use the DoseRight 2.0 AEC system in the 'manual' mode of operation. This method used a uniform phantom to generate reference images which form the basis for how the AEC system calculates exposure factors for any given patient. The results of this study have demonstrated excellent agreement in the configuration of the CT scanners in terms of average patient dose and image quality when using this technique. This work highlights the importance of CT protocol harmonisation in a modern Radiology department to ensure both consistent image quality and radiation dose. Following this study, the average radiation dose for a range of CT examinations has been reduced without any negative impact on clinical image quality.

Infant abusive head trauma prevention: acceptability of the Period of PURPLE Crying® program in far North Queensland, Australia

INTRODUCTION

A study examined the appropriateness and likelihood of usage of the north American Period of PURPLE Crying® intervention program in far north Queensland, to educate families about the risk of infant abusive head trauma (AHT)/shaken baby syndrome.

METHODS

A mixed-method cross-sectional study with a questionnaire and semi-structured interview was conducted with 33 health professionals in far north Queensland (FNQ) to gauge their opinions of the Period of PURPLE Crying program's educational materials.

RESULTS

Seventy per cent of participants were aware of infant AHT; 87.8% agreed the program would be appropriate for far north Queensland populations; 90% agreed that new parents/carers could learn new strategies to deal with inconsolable crying, and that men would be particularly advantaged.

CONCLUSIONS

In their present form, the educational materials of the Period of PURPLE Crying are appropriate for use. As such, the researchers intend to undertake a pilot implementation in FNQ.

A phase 1 study of OSI-930 in combination with erlotinib in patients with advanced solid tumours

AIM

To determine the maximum tolerated dose (MTD) of OSI-930 that can be combined with erlotinib, and establish recommended phase 2 doses when both agents are administered daily in patients with advanced solid tumours.

PATIENTS AND METHODS

Eligible patients with advanced solid tumours were enrolled into this standard "three+three" dose escalation study. Study treatment commenced on day 1 with OSI-930, and erlotinib was introduced on day 8. PK profiles of OSI-930, erlotinib and its active metabolite, OSI-420, were determined. Changes in sVEGFR2 as a pharmacodynamic biomarker of OSI-930 activity were assessed.

RESULTS

Twenty one patients were enrolled to 1 of 3 cohorts: 200 mg OSI-930 BID+100 mg erlotinib QD; 200 mg OSI-930 BID+150 mg erlotinib QD; 300 mg OSI-930 BID+150 mg erlotinib QD. The most common adverse events were anorexia (85%), diarrhoea (75%), rash (70%) and lethargy (65%). The MTD was not reached but the onset of cumulative toxicity necessitating dose modification after the 28-d DLT assessment period was common at the highest dose level. A PK interaction was identified with co-administration of both agents resulting in a two-fold increase in OSI-930 exposure. Pharmacodynamic activity was observed with a decline in sVEGFR levels detected in all patients. Ten patients had disease stabilization (median duration 119 d).

CONCLUSIONS

200 mg OSI-930 BID+150 mg erlotinib QD were the recommended doses for further evaluation of this combination.

Cognitive function in postmenopausal women receiving adjuvant letrozole or tamoxifen in the Breast International Group (BIG) 1–98 trial

510

Background: Hormonal therapy for breast cancer (BC) may affect cognition. Methods: Post-menopausal women with hormone receptor positive, early-stage BC were randomized to receive either: A) tamoxifen for 5 years; B) letrozole for 5 years; C) tamoxifen for 2 years followed by letrozole for 3 years; or D) letrozole for 2 years followed by tamoxifen for 3 years, as adjuvant endocrine treatment. During the fifth year of trial treatment, objective cognitive function (speed of psychomotor function, visual attention, working and verbal memory, learning) was evaluated by computerized tests. The difference in the composite score for patients taking letrozole (B+C; N= 65) versus tamoxifen (A+D; N = 55) at the time of testing was the primary comparison. Scores for each domain were standardized according to age-specific norms. Two-way ANOVA controlling for language was used to test the effect of treatment on cognitive function. Self-reported subjective cognitive function, psychological distress, fatigue and quality of life were also assessed. Results: Patient characteristics were balanced between groups. Both groups performed below age norms on most domains. The group taking letrozole had better overall cognitive function than the tamoxifen group (difference in mean composite scores = 0.278, p = 0.038, 95% CI: 0.015–0.540) and outperformed patients on tamoxifen for all domains (n.s.). Comparison of monotherapy arms A versus B supported better cognitive function among letrozole patients. Subjective cognitive function, psychological distress, fatigue, and quality of life did not differ between groups. Conclusions: Although letrozole results in lower circulating estrogen levels than tamoxifen, in this study BC patients taking adjuvant letrozole during the fifth year of treatment had better cognitive functioning than those taking tamoxifen.

[Table: see text]

Second female case of Myhre syndrome

Myhre syndrome is a rare disorder characterized by low birthweight, short stature, mental retardation, facial dysmorphism (blepharophimosis, midfacial hypoplasia, prognathism), heart anomalies, muscle hypertrophy, decreased joint mobility and deafness. To date 11 male cases and only one female case have been reported. This paper describes the second female case and compares the clinical and radiological findings between female and male patients.

Inactivation of DsbA alters the behaviour of Shigella flexneri towards murine and human-derived macrophage-like cells

The mutants of Shigella flexneri, Sh4 (dsbA::kan) and Sh42 (dsbA33G), behave differently towards murine and human-derived macrophage-like cells in vitro. Sh4 was trapped in the phagocytic vacuoles of the murine J774 cells as evidenced by its colony forming units plus and minus chloroquine exposure in a gentamicin protection assay, and by light and transmission electron microscopy (TEM). Sh42, similar to the wild-type M90TS, was able to escape from the vacuoles and kill host cells presumably by inducing apoptosis. In U937 cells, unlike M90TS that was free in the cytosol, both Sh4 and Sh42 grew poorly. TEM revealed that Sh4 and Sh42 were trapped within the U937 phagocytic vacuoles. Furthermore, the two mutants induced different patterns of interleukin-1beta and tumour necrosis factor-alpha expression, which might explain why they possess different immunogenic properties in vivo.

Level of lung function required to use the Camic Datamaster breath alcohol testing device

In the UK a person who, without reasonable excuse, fails to provide a breath specimen when required to under the 1988 Road Traffic Act, is guilty of an offense. In the past many suspects claim to have experienced difficulty providing breath samples for evidential machines. This paper describes experiments carried out on human subjects, both healthy and suffering a variety of respiratory illness. The experiments were designed to assess the level of respiratory performance required to provide a satisfactory breath sample for the Camic Datamaster. In this study it was found that both actual spirometry values and the percentage of predicted values were both important indicators.

Tackling latex allergy with a product database

Health care professionals, hospital patients and rubber industry workers have noted a marked increase in allergic reactions to natural rubber latex.

Gene-targeted therapeutic strategies--Royal Pharmaceutical Society Symposium. 9-10 December 1999, London, UK

This meeting highlighted the approaches that are currently available for gene-targeted therapeutics. The meeting focused on two strategies: antigene and anti-message. Polyamides (an example of antigene targeting) have exhibited significant antiviral activity, particularly against AIDS. The design of these agents and the mechanisms by which these compounds interact with DNA were discussed. Antisense oligonucleotides and ribozymes, agents used in the anti-message strategies, are proving to be attractive drug candidates for cancer chemotherapy. Antisense technology has been used for patients with B-cell lymphomas, resulting in complete remission of the disease in some cases. The unavailability of appropriate delivery systems for these DNA-targeting drugs continues to limit their widespread use. As was emphasized in this meeting, DNA-targeting drugs will continue to play an important role in clinical medicine for the foreseeable future.

Can wine tasting be used as a defence to a charge of excess alcohol?

Wine-tasting has been used as a defence in the UK to charges of driving with excess alcohol on the breath. There is little scientific data to support this explanation. The authors carried out an experimental wine-tasting using twelve volunteer subjects. Breath alcohol samples were taken at the start of the experiment and fifteen minutes after the end. All subjects after wine-tasting had breath alcohol levels below the instrumental limit of detection. The authors conclude that the wine-tasting defence is not credible.