O 089 - A soft robotic exosuit assisting the paretic ankle in patients post-stroke: Effect on muscle activation during overground walking

This study compared overground walking with and without exosuit assistance in post-stroke patients. Exosuit-assisted walking was found to improve paretic propulsion and ground clearance during swing, two common gait deviations in stroke patients. No changes in leg muscle activity was found, motivating further study of the exosuit as a tool for gait training during stroke rehabilitation.

TNF-inhibitors or bisphosphonates in chronic nonbacterial osteomyelitis? - Results of an international retrospective multicenter study

Chronic nonbacterial osteomyelitis (CNO) can cause significant morbidity, including bone pain and damage. In the absence of clinical trials, treatments include non-steroidal anti-inflammatory drugs, corticosteroids, TNF-inhibitors (TNFi) and/or bisphosphonates. In a retrospective chart review in the United Kingdom and Germany, we investigated response to TNFi and/or pamidronate. Ninety-one patients were included, receiving pamidronate (n = 47), TNFi (n = 22) or both sequentially (n = 22). Patients with fatigue [p = 0.003] and/or arthritis [p = 0.002] were more frequently treated with TNFi than pamidronate. Both therapies were associated with clinical remission at 6 months, and reduction of bone lesions on MRI at 12 months. While not reaching statistical significance, pamidronate resulted in faster resolution of MRI lesions. Fewer flares were observed with TNFi. Failure to respond to pamidronate was associated with female sex [p = 0.027], more lesions on MRI [p = 0.01] and higher CRP levels [p = 0.03]. Randomized clinical trials are needed to confirm observations and generate evidence.

A seafood risk tool for assessing and mitigating chemical and pathogen hazards in the aquaculture supply chain

Intricate links between aquatic animals and their environment expose them to chemical and pathogenic hazards, which can disrupt seafood supply. Here we outline a risk schema for assessing potential impacts of chemical and microbial hazards on discrete subsectors of aquaculture-and control measures that may protect supply. As national governments develop strategies to achieve volumetric expansion in seafood production from aquaculture to meet increasing demand, we propose an urgent need for simultaneous focus on controlling those hazards that limit its production, harvesting, processing, trade and safe consumption. Policies aligning national and international water quality control measures for minimizing interaction with, and impact of, hazards on seafood supply will be critical as consumers increasingly rely on the aquaculture sector to supply safe, nutritious and healthy diets.

Assessment, causes and consequences of short opercula in laboratoryreared Atlantic salmon (Salmo salar)

Opercular deformity is a common morphological abnormality of laboratory and other cultured fishes, observed in a wide variety of species but with an unclear aetiology. Following observations of short opercula in stocks of Atlantic salmon (Salmo salar) reared in our laboratory, we developed a photographic key to score individual fish on a scale of 1 to 5. Inter-rater reliability was assessed as 'almost perfect'. This visual method is quick and simple to use, can be used to score live fish in situ in tanks as well as sampled fish, does not require sophisticated equipment and provides quantitative information to investigate the aetiology of short opercula. Opercular size was scored for a cohort of in-house reared Atlantic salmon, in a time series of random samples of ≥ 30 fish (mean weights ranging from 0.8 to 299 g) over 14 months. Short opercula were first recorded during the parr stage, prevalence and severity increased as the fish grew, and the deformity was asymmetrical, occurring predominantly on the left side. Therefore, among the many potential causal factors, nipping is suggested as the primary cause of short opercula within our culture system, with asymmetry due to the clockwise current. We also present evidence that short opercula are associated with gill damage which supports this deformity being a welfare issue that merits assessment.

COVID-19 vaccination intent among London healthcare workers

Background

The 10-month timeline from conception to regulatory approval of the Pfizer–BioNTech vaccine against SARS-CoV-2 is unprecedented in modern medicine. However, the climate of the pandemic has also seen anti-vaccination sentiments flourish.

Aims

To determine the intent to accept COVID-19 vaccination among healthcare workers at a London Hospital Trust and examine variation in uptake between demographic groups.

Methods

We conducted a cross-sectional survey open to staff working at the trust. Staff rated on a five-point scale the likelihood of them accepting COVID-19 vaccination.

Results

We received 514 responses, representing 16% of the workforce. About 59% of staff intended to seek vaccination, 24% to reject and 17% were unsure. There was significantly reduced intended uptake in females, younger age groups, healthcare assistants, nurses, staff of black ethnic backgrounds and those who rejected influenza vaccination. Safety was the dominant concern.

Conclusions

Our study finds COVID-19 vaccinate hesitancy is prevalent among healthcare workers at a London Hospital Trust. It is particularly concerning that hesitancy was highest amongst groups most exposed to COVID-19 and most at risk of severe disease. Reasons behind disparities in uptake must be addressed to protect staff and prevent deepening inequalities within the healthcare workforce.

Origin of Groundwater Arsenic in a Rural Pleistocene Aquifer in Bangladesh Depressurized by Distal Municipal Pumping

Across South Asia, millions of villagers have reduced their exposure to high-arsenic (As) groundwater by switching to low-As wells. Isotopic tracers and flow modeling are used in this study to understand the groundwater flow system of a semi-confined aquifer of Pleistocene (>10 kyr) age in Bangladesh that is generally low in As but has been perturbed by massive pumping at a distance of about 25 km for the municipal water supply of Dhaka. A 10- to 15-m-thick clay aquitard caps much of the intermediate aquifer (>40- to 90-m depth) in the 3-km² study area, with some interruptions by younger channel sand deposits indicative of river scouring. Hydraulic heads in the intermediate aquifer below the clay-capped areas are 1-2 m lower than in the high-As shallow aquifer above the clay layer. In contrast, similar heads in the shallow and intermediate aquifer are observed where the clay layer is missing. The head distribution suggests a pattern of downward flow through interruptions in the aquitard and lateral advection from the sandy areas to the confined portion of the aquifer. The interpreted flow system is consistent with ³H-³He ages, stable isotope data, and groundwater flow modeling. Lateral flow could explain an association of elevated As with high methane concentrations within layers of gray sand below certain clay-capped portions of the Pleistocene aquifer. An influx of dissolved organic carbon from the clay layer itself leading to a reduction of initially orange sands has also likely contributed to the rise of As.

European Specialty Examination in Gastroenterology and Hepatology examination — improving education in gastroenterology and hepatology

The Federation of Royal Colleges, the British Society of Gastroenterology (BSG) and the European Section and Board of Gastroenterology and Hepatology developed the European Specialty Examination in Gastroenterology and Hepatology (ESEGH) from the United Kingdom Specialty Certificate Examination, which was the original examination. Since 2018 the Specialty Certificate Examination and the ESEGH were combined into a single exam, identical across Europe and the rest of the world. The ESEGH is mandated in 4 countries (United Kingdom, Switzerland, The Netherlands and Malta) and the number of entries increased from 50 in 2014 to 490 in 2019. Candidates from countries were the ESEGH is not mandated are sitting the Exam, showing us they realize the enormous interest of holding a certificate for knowledge in their Curriculum. We also have an increasing number of candidates from countries outside Europe.

Improved betulinic acid biosynthesis using synthetic yeast chromosome recombination and semi-automated rapid LC-MS screening

Synthetic biology, genome engineering and directed evolution offer innumerable tools to expedite engineering of strains for optimising biosynthetic pathways. One of the most radical is SCRaMbLE, a system of inducible in vivo deletion and rearrangement of synthetic yeast chromosomes, diversifying the genotype of millions of Saccharomyces cerevisiae cells in hours. SCRaMbLE can yield strains with improved biosynthetic phenotypes but is limited by screening capabilities. To address this bottleneck, we combine automated sample preparation, an ultra-fast 84-second LC-MS method, and barcoded nanopore sequencing to rapidly isolate and characterise the best performing strains. Here, we use SCRaMbLE to optimise yeast strains engineered to produce the triterpenoid betulinic acid. Our semi-automated workflow screens 1,000 colonies, identifying and sequencing 12 strains with between 2- to 7-fold improvement in betulinic acid titre. The broad applicability of this workflow to rapidly isolate improved strains from a variant library makes this a valuable tool for biotechnology.

The Impact of Aquifer Flushing on Groundwater Arsenic Across a 35-km Transect Perpendicular to the Upper Brahmaputra River in Assam, India

Well testing in the floodplain of the Brahmaputra River in Golaghat and Jorhat districts of Assam, India, shows that groundwater arsenic (As) concentrations increase with distance from the river. To establish the origin of this pattern, an additional 900 wells <60 m deep were tested for As and 9 sites were drilled along a 35-km transect perpendicular to the river. The field data show no relation between groundwater As concentrations ranging from <1 to 660 μg/L along the transect and (a) As concentrations of <1-5 mg/kg in cuttings of aquifer sand recovered while drilling or (b) the degree of reduction of iron oxides in these cuttings. The drilling indicates, however, a marked increase in the thickness of a clay layer capping the aquifer starting from <1-5 m near the river to over 60 m at the most distant site towards the base of the Naga foothills. Organic radiocarbon ages of 18-46 kyr obtained from all but one of 13 clay samples indicate pre-Holocene deposition of the underlying sands across the entire transect. Radiocarbon ages of dissolved inorganic carbon of 0.2, 4.7, and 17.8 kyr were measured in groundwater from 3 monitoring wells installed to 30-60 m depth at distances of 10, 20, and 40 km from the river, respectively. A conceptual groundwater flow model consistent with monitored heads and groundwater ages suggests that thick clay layers capping the aquifer further from the river inhibited flushing of the aquifer and, as a result, preserved higher As levels in groundwater.

Rapid Prototyping Platform for Saccharomyces cerevisiae Using Computer-Aided Genetic Design Enabled by Parallel Software and Workcell Platform Development

Biofoundries have enabled the ability to automate the construction of genetic constructs using computer-aided design. In this study, we have developed the methodology required to abstract and automate the construction of yeast-compatible designs. We demonstrate the use of our in-house software tool, AMOS, to coordinate with design software, JMP, and robotic liquid handling platforms to successfully manage the construction of a library of 88 yeast expression plasmids. In this proof-of-principle study, we used three fluorescent genes as proxy for three enzyme coding sequences. Our platform has been designed to quickly iterate around a design cycle of four protein coding sequences per plasmid, with larger numbers possible with multiplexed genome integrations in Saccharomyces cerevisiae. This work highlights how developing scalable new biotechnology applications requires a close integration between software development, liquid handling robotics, and protocol development.

Rapid host strain improvement by in vivo rearrangement of a synthetic yeast chromosome

Synthetic biology tools, such as modular parts and combinatorial DNA assembly, are routinely used to optimise the productivity of heterologous metabolic pathways for biosynthesis or substrate utilisation, yet it is well established that host strain background is just as important for determining productivity. Here we report that in vivo combinatorial genomic rearrangement of Saccharomyces cerevisiae yeast with a synthetic chromosome V can rapidly generate new, improved host strains with genetic backgrounds favourable to diverse heterologous pathways, including those for violacein and penicillin biosynthesis and for xylose utilisation. We show how the modular rearrangement of synthetic chromosomes by SCRaMbLE can be easily determined using long-read nanopore sequencing and we explore experimental conditions that optimise diversification and screening. This synthetic genome approach to metabolic engineering provides productivity improvements in a fast, simple and accessible way, making it a valuable addition to existing strain improvement techniques.

The Sc2.0 project has built the Synthetic Chromosome Rearrangement and Modification by LoxP-mediated Evolution (SCRaMbLE) system into their synthetic chromosomes. Here the authors use SCRaMbLE to rapidly develop, diversify and screen strains for diverse production and growth characteristics.

Evidence for Elevated Levels of Arsenic in Public Wells of Bangladesh Due To Improper Installation

One of the mainstays of mitigation to reduce the exposure of the rural population of Bangladesh to arsenic (As) from private, mostly <90-m deep wells over the past 15 years has been the installation of over 300,000 deeper community wells. A comprehensive testing campaign previously conducted across a 180 km² of area of Bangladesh identified 9 out of total of 927 wells >90 m deep that contained >50 µg/L arsenic. We show here that for five of these nine wells, conductivity profiles obtained after spiking the well bore with salt indicate a shallow leak that could explain the high As in the well water. In two of the five leaky wells, the presence of additional screens at the depth of the leak was documented with a downhole camera. The downhole camera did not detect anomalies in the construction of the remaining three leaky wells or in the four wells that did not leak. The four wells that did not leak were all >150-m deep and located in two villages separated by less than 500 m. Excluding these two villages and a handful of leaky wells, the results indicate an aquifer that is consistently low in As over a sizeable area at depths >90 m. Isolated cases of public wells that are elevated in As that have been reported elsewhere in Bangladesh may therefore reflect improper installation rather than actual contamination of the deep aquifer.

Modulation of human allogeneic and syngeneic pluripotent stem cells and immunological implications for transplantation

Tissues derived from induced pluripotent stem cells (iPSCs) are a promising source of cells for building various regenerative medicine therapies; from simply transplanting cells to reseeding decellularized organs to reconstructing multicellular tissues. Although reprogramming strategies for producing iPSCs have improved, the clinical use of iPSCs is limited by the presence of unique human leukocyte antigen (HLA) genes, the main immunologic barrier to transplantation. In order to overcome the immunological hurdles associated with allogeneic tissues and organs, the generation of patient-histocompatible iPSCs (autologous or HLA-matched cells) provides an attractive platform for personalized medicine. However, concerns have been raised as to the fitness, safety and immunogenicity of iPSC derivatives because of variable differentiation potential of different lines and the identification of genetic and epigenetic aberrations that can occur during the reprogramming process. In addition, significant cost and regulatory barriers may deter commercialization of patient specific therapies in the short-term. Nonetheless, recent studies provide some evidence of immunological benefit for using autologous iPSCs. Yet, more studies are needed to evaluate the immunogenicity of various autologous and allogeneic human iPSC-derived cell types as well as test various methods to abrogate rejection. Here, we present perspectives of using allogeneic vs. autologous iPSCs for transplantation therapies and the advantages and disadvantages of each related to differentiation potential, immunogenicity, genetic stability and tumorigenicity. We also review the current literature on the immunogenicity of syngeneic iPSCs and discuss evidence that questions the feasibility of HLA-matched iPSC banks. Finally, we will discuss emerging methods of abrogating or reducing host immune responses to PSC derivatives.

Discarded Human Thymus Is a Novel Source of Stable and Long-Lived Therapeutic Regulatory T Cells

Regulatory T cell (Treg)-based therapy is a promising approach to treat many immune-mediated disorders such as autoimmune diseases, organ transplant rejection, and graft-versus-host disease (GVHD). Challenges to successful clinical implementation of adoptive Treg therapy include difficulties isolating homogeneous cell populations and developing expansion protocols that result in adequate numbers of cells that remain stable, even under inflammatory conditions. We investigated the potential of discarded human thymuses, routinely removed during pediatric cardiac surgery, to be used as a novel source of therapeutic Tregs. Here, we show that large numbers of FOXP3(+) Tregs can be isolated and expanded from a single thymus. Expanded thymic Tregs had stable FOXP3 expression and long telomeres, and suppressed proliferation and cytokine production of activated allogeneic T cells in vitro. Moreover, expanded thymic Tregs delayed development of xenogeneic GVHD in vivo more effectively than expanded Tregs isolated based on CD25 expression from peripheral blood. Importantly, in contrast to expanded blood Tregs, expanded thymic Tregs remained stable under inflammatory conditions. Our results demonstrate that discarded pediatric thymuses are an excellent source of therapeutic Tregs, having the potential to overcome limitations currently hindering the use of Tregs derived from peripheral or cord blood.

Out-of-season production of 17,20β-dihydroxypregn-4-en-3-one in the roach Rutilus rutilus

In this study, although the highest production of two physiologically significant progestins in teleosts [17,20β-dihydroxypregn-4-en-3-one (17,20β-P) and 17,20β,21-trihydroxypregn-4-en-3-one (17,20β,21-P)] was observed in the period just prior to spawning in both male and female roach Rutilus rutilus, there was also a substantial production (mean levels of 5-10 ng ml(-1) in blood; and a rate of release of 5-20 ng fish(-1)  h(-1) into the water) in males and females in the late summer and early autumn (at least 7 months prior to spawning). During this period, the ovaries were increasing rapidly in size and histological sections were dominated by oocytes in the secondary growth phase [i.e. incorporation of vitellogenin (VTG)]. At the same time, the testes were also increasing rapidly in size and histological sections were dominated by cysts containing mainly spermatogonia type B. Measurements were also made of 11-ketotestosterone (11-KT) in males and 17β-oestradiol and VTG in females. The 3 months with the highest production of 11-KT coincided with the period that spermatozoa were present in the testes. In females, the first sign of a rise in 17β-oestradiol concentrations coincided with the time of the first appearance of yolk globules in the oocytes (in August). The role of the progestins during the late summer and autumn has not been established.

Carcinoid tumor of the lung metastatic to a previously identified pituitary adenoma

The authors present the case of a 58-year-old gentleman presenting with atypical carcinoid tumor of primary lung origin metastasizing to a previously identified pituitary macroadenoma. The patient presented with symptoms of headache and visual disturbance. Imaging revealed enlargement of a known sellar mass as well as three separate enhancing lesions in the brain parenchyma. Resection was accomplished via a transnasal transshpenoidal approach without complication. Immunoreactivity was demonstrated to synaptophysin, chromogranin, CD56, epithelial membrane antigen, and thyroid transcription factor-1. The specimen was also marked by negative staining for pituitary hormones. This case demonstrates a rare occurrence of metastastic spread of tumor to a previously identified pituitary macroadenoma.

Achieving consensus on current and future priorities for farmed fish welfare: a case study from the UK

The welfare of farmed fish has attracted attention in recent years, which has resulted in notable changes within the aquaculture industry. However, a lack of communication between stakeholders and opposing ethical views are perceived as barriers to achieving consensus on how to improve farmed fish welfare. To address these issues, we developed an interactive approach that could be used during stakeholder meetings to (1) improve communication between different stakeholder groups, (2) build consensus on priorities for farmed fish welfare and (3) establish mechanisms to address welfare priorities. We then applied this approach during a meeting of stakeholders to identify current and future priorities for farmed fish welfare in the UK. During the meeting in the UK, stakeholders initially identified 32 areas that they felt were in need of development for future improvements in farmed fish welfare. These were further refined via peer review and discussion to the seven most important "priority" areas. Establishing a "better understanding of what good fish welfare is" emerged as the highest priority area for farmed fish welfare. The second highest priority area was "the need for welfare monitoring and documentation systems", with mortality recording proposed as an example. The other five priority areas were "[improved understanding of] the role of genetic selection in producing fish suited to the farming environment", "a need for integration and application of behavioural and physiological measures", "the need for a more liberal regime in Europe for introducing new medicines", "a need to address the issues of training existing and new workers within the industry", and "ensuring best practise in aquaculture is followed by individual businesses". Feedback from attendees, and the meeting outputs, indicated that the approach had been successful in improving communication between stakeholders and in achieving consensus on the priorities for farmed fish welfare. The approach therefore proved highly beneficial for future improvements in fish welfare in the UK.

Extending the clinical research network approach to all of healthcare

The development of Clinical Research Networks (CRN) has been central to the work conducted by Health Departments and research funders to promote and support clinical research within the NHS in the UK. In England, the National Institute for Health Research has supported the delivery of clinical research within the NHS primarily through CRN. CRN provide the essential infrastructure within the NHS for the set up and delivery of clinical research within a high-quality peer-reviewed portfolio of studies. The success of the National Cancer Research Network is summarized in Chapter 5. In this chapter progress in five other topics, and more recently in primary care and comprehensively across the NHS, is summarized. In each of the 'topic-specific' networks (Dementias and Neurodegenerative Diseases, Diabetes, Medicines for Children, Mental Health, Stroke) there has been a rapid and substantial increase in portfolios and in the recruitment of patients into studies in these portfolios. The processes and the key success factors are described. The CRN have worked to support research supported by pharmaceutical, biotechnology and medical device companies and there has been substantial progress in improving the speed, cost and delivery of these 'industry' studies. In particular, work to support the increased speed of set up and delivery of industry studies, and to embed this firmly in the NHS, was explored in the North West of England in an Exemplar Programme which showed substantial reductions in study set-up times and improved recruitment into studies and showed how healthcare (NHS) organizations can overcome delays in set up times when they actively manage the process. Seven out of 20 international studies reported that the first patient to be entered anywhere in the world was from the UK. In addition, the CRN have supported research management and governance, workforce development and clinical trials unit collaboration and coordination. International peer reviews of all of the CRN have been positive and resulted in the continuation of the system for a further 5 years in all cases.

Which measures of physical function and motor impairment best predict quality of life in Parkinson's disease?

INTRODUCTION

Our objective was to compare the relative value of elements of the motor system in predicting the physical mobility domain of health related quality of life in patients with Parkinson's disease in order to specify targets for intervention.

METHODS

In this cross-sectional study, the Parkinson's disease questionnaire-39 was administered to 263 subjects with Parkinson's disease to assess health related quality of life. Demographics, motor impairments and physical function were assessed using the Unified Parkinson disease rating scale, 10-m walk test, 6-min walk test, Freezing of gait questionnaire, Timed up & go, functional gait assessment, Berg balance test, functional reach and 9-hole peg test.

RESULTS

The results revealed that demographic factors accounted for 19.7% of the variance in Parkinson disease questionnaire-39 mobility score. When motor impairments were added to the model, the bradykinesia composite score contributed a significant portion of the variance (R(2) change = 0.12, p < 0.001). The tremor and rigidity composite scores did not contribute significantly. The Freezing of gait questionnaire was the strongest predictor (R(2) change = 0.23, p < 0.001) of the physical function tests followed by Functional gait assessment (R(2) change = 0.06, p < 0.001) and 6-min walk test (R(2) change = 0.01, p = 0.01). Collectively, 61% of the variance in Parkinson disease questionnaire-39 mobility score and 41.5% of the Parkinson disease questionnaire-39(total) score was accounted for.

DISCUSSION

These results suggest greater value of physical function tests, and not tests of motor impairments, in predicting health related quality of life.

Virological and molecular epidemiological investigations into the role of wild birds in the epidemiology of influenza A/H5N1 in central Thailand

A serological and virological surveillance program to investigate the HPAI H5N1 virus in wild bird populations was undertaken from February 2007 to October 2008. The purpose of the survey was to investigate the infection status in free ranging wild birds in Banglane district, Nakhon Pathom province, central Thailand. Samples from wild birds were collected every two months. Choanal and cloacal swabs, serum and tissue samples were collected from 421 birds comprising 44 species. Sero-prevalence of the virus tested by H5N1 serum neutralization test (using a H5N1 virus clade 1; A/chicken/Thailand/vsmu-3-BKK/2004) was 2.1% (8 out of 385 samples; 95% CI 0.7, 3.5). Species that were antibody positive included rock pigeons (Columba livia), Asian pied starling (Gracupica contra), spotted dove (Streptopelia chinensis), oriental magpie robin (Copsychus saularis), blue-tailed bee-eater (Merops philippinus), myna (Acridotheres spp.), and pond heron (Ardeola spp.). Prevalence by H5N1 virus isolation was 0.5% (2 out of 421 samples; 95% CI 0.0, 1.1); the two H5N1 virus-positive samples were from Asian pied starling (Gracupica contra) and white vented myna (Acridotheres grandis). Positive virological samples were collected in June 2007 while all positive serology samples were collected between May and August except for one sample collected in December 2007. No positive samples were collected in 2008. Molecular studies revealed that the wild bird H5N1 viruses were closely related to poultry viruses isolated in other parts of Thailand. However, there was no poultry H5N1 prevalence study performed in the study site during the time of this wild bird survey. Interpretation of source of virus isolates would include spill-over of H5N1 viruses from contaminated sources due to movement of domestic poultry and/or fomites from other areas; or infection of wild birds within the outbreak locations and then translocation by wild bird movement and interaction with wild birds inhabiting distant locations.

Visual discrimination between two sexually deceptive Ophrys species by a bee pollinator

Almost all species of the orchid genus Ophrys are pollinated by sexual deception. The orchids mimic the sex pheromone of receptive female insects, mainly hymenopterans, in order to attract males seeking to copulate. Most Ophrys species have achromatic flowers, but some exhibit a coloured perianth and a bright, conspicuous labellum pattern. We recently showed that the pink perianth of Ophrys heldreichii flowers increases detectability by its pollinator, males of the long-horned bee Eucera berlandi. Here we tested the hypothesis that the bright, complex labellum pattern mimics the female of the pollinator to increase attractiveness toward males. In a dual-choice test we offered E. berlandi males an O. heldreichii flower and a flower from O. dictynnae, which also exhibits a pinkish perianth but no conspicuous labellum pattern. Both flowers were housed in UV-transmitting acrylic glass boxes to exclude olfactory signals. Males significantly preferred O. heldreichii to O. dictynnae flowers. In a second experiment, we replaced the perianth of both flowers with identical artificial perianths made from pink card, so that only the labellum differed between the two flower stimuli. Males then chose between both stimuli at random, suggesting that the presence of a labellum pattern does not affect their choice. Spectral measurements revealed higher colour contrast with the background of the perianth of O. heldreichii compared to O. dictynnae, but no difference in green receptor-specific contrast or brightness. Our results show that male choice is guided by the chromatic contrast of the perianth during the initial flower approach but is not affected by the presence of a labellum pattern. Instead, we hypothesise that the labellum pattern is involved in aversive learning during post-copulatory behaviour and used by the orchid as a strategy to increase outcrossing.

Patched1 deletion increases N-Myc protein stability as a mechanism of medulloblastoma initiation and progression

Medulloblastoma tumorigenesis caused by inactivating mutations in the PATCHED1 (PTCH1) gene is initiated by persistently activated Sonic Hedgehog (Shh) signaling in granule neuron precursors (GNPs) during the late stages of cerebellar development. Both normal cerebellar development and Shh-driven medulloblastoma tumorigenesis require N-Myc expression. However, the mechanisms by which N-Myc affects the stages of medulloblastoma initiation and progression are unknown. Here we used a mouse model of Ptch1 heterozygosity and medulloblastoma to show that increased N-Myc expression characterized the earliest selection of focal GNP hyperplasia destined for later tumor progression. Step-wise loss of Ptch1 expression, from tumor initiation to progression, led to incremental increases in N-Myc protein, rather than mRNA, expression. Increased N-Myc resulted in enhanced proliferation and death resistance of perinatal GNPs at tumor initiation. Sequential N-Myc protein phosphorylation at serine-62 and serine-62/threonine-58 characterized the early and late stages of medulloblastoma tumorigenesis, respectively. Shh pathway activation led to increased Myc protein stability and reduced expression of key regulatory factors. Taken together our data identify N-Myc protein stability as the result of loss of Ptch1, which distinguishes normal cerebellar development from medulloblastoma tumorigenesis.

Clinical and Radiological Grading of Superior Vena Cava Obstruction

BACKGROUND

Superior vena cava obstruction (SVCO) is commonly caused by neoplastic venous compression and presents with typical symptoms and signs. Its clinical severity presumably depends on the degree of obstruction and the adequacy of venous collateral formation.

OBJECTIVES

The development of novel clinical and radiological scoring systems based on the postulate that a reproducible relationship exists between the degree of SVCO, the presence of collateral circulation and the extent of clinical symptoms.

METHODS

We prospectively evaluated consecutive cases of acute and subacute SVCO with a newly developed clinical scoring system, which is based on easily detectable clinical symptoms and signs of SVCO. In parallel, we recorded and scored the degree of SVCO and the extent of collaterals visible on contrast-enhanced computed tomography (CT).

RESULTS

Thirty-four cases of SVCO were evaluated: 8 (23.5%) were clinically mild, 16 (47%) moderate and 10 (29.5%) severe. Lung cancer was the underlying histological diagnosis in 94% of cases. Radiologically, 53% had complete SVCO. A well-developed collateral system was found in 14 (41%). A scoring system subtracting a 'collateral score' from an 'obstruction score' showed a significant correlation with the clinical score (r = 0.75, p < 0.01).

CONCLUSIONS

Clinical severity of SVCO depends upon the degree of SVCO and is ameliorated by collateral formation. The novel clinical scoring system can predict the underlying CT features in SVCO and may be valuable in the bedside assessment of SVCO severity.

A phase II trial of thalidomide (Thal) and procarbazine (Pro) in adults with recurrent or progressive malignant gliomas (MG)

2067

Background: Thal and Pro are among the few agents with demonstrated activity against MG. A two-stage, phase II trial was initiated within the WFURB to establish the response rate of combination Thal-Pro in patients (pts) with recurrent or progressive MG. Methods: Eligibility included pt age = 18 with measurable tumor on contrast enhanced brain scans; KPS = 60; normal liver, kidney and hematologic function; and treatment with = 2 prior regimens. Pts were required to participate in the S.T.E.P.S. Program and mandated to comply with agreed upon measures to avoid conception. Protocol therapy included Pro 250mg/m2/d x 5d q 28days and Thal 200mg/day continuously. Intrapatient dose escalation of Thal was attempted (increase by 100mg/day weekly as tolerated) to a maximum of 800mg/day. All pts received daily pyridoxine(100mg), warfarin(1mg) and stool softeners/laxatives. MRI/CT scans were performed prior to each odd cycle (every 8 weeks) to assess response based upon changes in the products of the largest bidimensional tumor diameters. Quality of life questionnaires including the FACT-Br were performed at baseline and prior to each odd cycle in all treated pts. Results: 18 pts (11 male) were enrolled (median age 50, range 27–63). One pt refused any therapy and is excluded from the analysis. The 17 treated pts received 36 cycles (median 2) of therapy. The median maximum Thal dose achieved was 400mg (range 200–800). No complete or partial responses were seen; 1 pt (6%) experienced stable disease, 14 (82%) progressed as best response and 2 (12%) were not evaluable for response. Median time to progression was 2.1 months (95% CI, 1.5–2.5). 14 pts have died; median survival was 7.6 months (95% CI, 3.5–9.4). Grade 3/4 drug related toxicity was minimal. Conclusions: Despite modest individual response rates in multiple prior phase II and III trials, the combination of Pro and Thal demonstrated no efficacy in this trial and this combination is unworthy of further investigation in pts with MG. Supported by NCI 1 U10 CA81851 and Celgene.

No significant financial relationships to disclose.

Using Unified Modelling Language (UML) as a process-modelling technique for clinical-research process improvement

The Primary Care Data Quality programme (PCDQ) is a quality-improvement programme which processes routinely collected general practice computer data. Patient data collected from a wide range of different brands of clinical computer systems are aggregated, processed, and fed back to practices in an educational context to improve the quality of care. Process modelling is a well-established approach used to gain understanding and systematic appraisal, and identify areas of improvement of a business process. Unified modelling language (UML) is a general purpose modelling technique used for this purpose. We used UML to appraise the PCDQ process to see if the efficiency and predictability of the process could be improved. Activity analysis and thinking-aloud sessions were used to collect data to generate UML diagrams. The UML model highlighted the sequential nature of the current process as a barrier for efficiency gains. It also identified the uneven distribution of process controls, lack of symmetric communication channels, critical dependencies among processing stages, and failure to implement all the lessons learned in the piloting phase. It also suggested that improved structured reporting at each stage - especially from the pilot phase, parallel processing of data and correctly positioned process controls - should improve the efficiency and predictability of research projects. Process modelling provided a rational basis for the critical appraisal of a clinical data processing system; its potential maybe underutilized within health care.

Fin erosion on rainbow trout on commercial trout farms in the United Kingdom

Fish weighing less than 30 g and more than 100 g were sampled from 38 rearing units on 10 commercial farms growing rainbow trout for the table market. A fin index was calculated for each of the eight rayed fins on 949 trout by dividing their length by the standard length of the fish. There was a large range in the indices of all eight fins. The fin indices of the small and large fish were compared, controlling for farm effect. With the exception of the dorsal fin, all the indices were larger for the small fish than for the large fish, but the magnitude of the difference was greater for some fins than others. In comparison with the fins of wild fish, the pectoral and dorsal fins appeared to be most eroded and the damage to these fins was evident even in the small fish. The erosion of the caudal, anal and ventral (or pelvic) fins was more prominent in the larger fish. Variations in the fin indices of the caudal, anal and ventral fins suggested that there was little variation between rearing units on the same farm, but that there was significant variation between individual fish in the same rearing units, and between fish on different farms.