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Trace elements (TEs) remain of significant toxicological concern as many are critical for global decarbonisation. TEs accumulate in sediments so benthic polychaetes (e.g. Hediste diversicolor and Alitta virens) are highly relevant for ecotoxicology. However, ecological/biological differences could influence TE accumulation and biomonitoring suitability. Exploiting multiple sympatric populations (Solent, UK), we measure sediment and tissue concentrations generating EFs (enrichment factors), AEIs (Adverse Effects Indexes) and tissue bioaccumulation factors. We also assess stable isotope compositions to elucidate diet influences. Despite diverse anthropogenic activity in the Solent, the majority of TEs present low levels of sediment contamination at the sites. For Ni, Pb and As, a combination of mean AEIs >1 and some sediment concentrations exceeding SQVs (Sediment Quality Values) indicate a slight toxicological risk. For Cu and Hg, high EFs and AEI scores confirm they are the greatest risk, thus requiring source identification/control. However, only mean As tissue concentrations reflect contaminated sites, therefore, identifying the As-source(s) is also a priority. Sediment and tissue concentration relationships were generally negative and not significant for both species. Although a significant negative relationship for Cd for A. virens requires further investigation, the lack of evidence for TE bioaccumulation from sediment may limit both species' biomonitoring suitability for low-contamination sites. Species differences in tissue concentration were also TE specific: H. diversicolor had significantly higher concentrations for Ag, Cu, Hg, Ni and Zn, whilst the reverse was true for Cd, Fe, Cr and As. Whilst ecological differences and that feeding sources are site and species-specific (as evidenced by C, N and S stable isotopes analysis) cannot be ignored, the diverse tissue concentrations strongly suggest different TE regulation strategies per species. Together these data will be important for ecotoxicologists and regulators to select the 'best' polychaete biomonitor and assess TE toxicity under future global decarbonisation trajectories for TE inputs., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Gordon Watson reports financial support was provided by European Union. Gordon Watson reports a relationship with European Union that includes: funding grants. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Globally, 6 million coral reef fishers provide ~25% of emergent countries' catch, but species have low value. The marine aquarium trade (MAT) targets high-value biodiversity, but missing data amplify draconian governance and demand for international prohibition. To stimulate sustainability and reef conservation investment, we generate a fiscal baseline using the first global analysis of numbers, diversity, and biomass of MAT-traded organisms. Each year, ~55 million organisms worth US$2.15 billion at retail are traded comparable with major fisheries, e.g., tuna. A sustainable MAT also requires overexploitation assessments. We identify 25 species/genera with "Extremely High" risk ratios and place the Indonesian and Sulu-Celebes Seas in the highest exploitation category. Despite predicted hobbyist number increases, unabated reef degradation and low governance will transform the MAT into an aquaculture-dominated industry decoupled from communities (i.e., culture located in importing countries). A "MAT-positive" future requires evidence-based management/governance, consumer education, and sustainable practice incentivization but can address the biodiversity and social and economic inequality crises.

Current approaches to measure ecosystem services (ES) within natural capital (NC) and nature-based solutions (NbS) assessments are generally coarse, often using a single figure for ecosystem services (e.g., nutrient remediation or blue carbon sequestration) applied to the local or national habitat stock, which fails to take account of local ecosystem conditions and regional variability. As such, there is a need for improved understanding of the link between habitat condition and ES provision, using comparable indicators in order to take more informed management decisions. Here the UK, Solent Marine Sites (SEMS) is used as a case study system to demonstrate how Water Framework Directive (WFD) 'ecological status' and other indicators of ecosystem condition (state or quality) can be coupled with habitat extent information to deliver a more precise locally-tailored NC approach for active coastal and marine habitat restoration. Habitat extent and condition data are collected for seven NbS relevant coastal habitats (littoral sediment, mat-forming green macroalgae, subtidal sediment, saltmarsh, seagrass, reedbeds and native oyster beds). The workflow includes: 1) biophysical assessment of regulatory ES; 2) monetary valuation; and 3) compilation of future scenarios of habitat restoration and creation. The results indicate that incorporating classifications by condition indices into local NC extent accounts improved ES benefits by 11-67%. This suggests that omitting condition from NC assessments could lead to undervaluation of ES benefits. Future scenarios of restoration in the SEMS also show that the additional regulatory benefits of reaching 'Good' ecological status are £376 million annually, but could be as much as £1.218 billion if 'High'status and all habitat creation targets were met. This evidence of the potential value of restoration and importance of including condition indices in assessments is highly relevant to consider when investing in water ecosystems conservation and restoration as called for by the UN Decade on Ecosystem Restoration (2021-2030), and more generally in global nutrient neutrality and blue carbon policy strategies., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 The Authors. Published by Elsevier B.V. All rights reserved.)

The biodiversity of marine and coastal habitats is experiencing unprecedented change. While there are well-known drivers of these changes, such as overexploitation, climate change and pollution, there are also relatively unknown emerging issues that are poorly understood or recognized that have potentially positive or negative impacts on marine and coastal ecosystems. In this inaugural Marine and Coastal Horizon Scan, we brought together 30 scientists, policymakers and practitioners with transdisciplinary expertise in marine and coastal systems to identify new issues that are likely to have a significant impact on the functioning and conservation of marine and coastal biodiversity over the next 5-10 years. Based on a modified Delphi voting process, the final 15 issues presented were distilled from a list of 75 submitted by participants at the start of the process. These issues are grouped into three categories: ecosystem impacts, for example the impact of wildfires and the effect of poleward migration on equatorial biodiversity; resource exploitation, including an increase in the trade of fish swim bladders and increased exploitation of marine collagens; and new technologies, such as soft robotics and new biodegradable products. Our early identification of these issues and their potential impacts on marine and coastal biodiversity will support scientists, conservationists, resource managers and policymakers to address the challenges facing marine ecosystems., (© 2022. The Author(s), under exclusive licence to Springer Nature Limited.)

Objective: Necrotising otitis externa is increasingly being seen and treated within the UK. The aim of this study was to explore the potential cost of a cohort of patients with necrotising otitis externa presenting to a single tertiary NHS trust., Method: This was a retrospective study with data from 14 patients with confirmed necrotising otitis externa who were treated, monitored, discharged or who died between October 2016 and November 2018. Direct costs using the tariffs from the 2018 to 2019 financial year included in-patient stay, imaging, peripheral inserted central catheter line cost, ENT and out-patient parenteral antibiotic therapy visits and antimicrobial duration., Results: The mean cost of treatment per patient was £17 615 (range, £9407 to £38 230) with an extreme outlier costing more than £122 000., Conclusion: Awareness and education at a primary care level and research into robust imaging to aid termination of treatment may lower costs in the future by catching pathology early and reducing treatment duration.

Coastal management requires cost-effective, yet accurate, assessments of habitat condition, especially in areas protected by statutory conservation measures. Unmanned Aerial Vehicles (UAVs) provide alternatives to manned aircraft and walk-over (WO) surveys. To support coastal managers with method selection, we compare the costs and benefits of the three techniques using the extent of bait collection (sediment scarring from manual digging) on intertidal mudflats from three UK sites. UAV and WO surveys were conducted in parallel and aerial photography was downloaded from the Channel Coastal Observatory (CCO). Digging was digitised from estimations on foot (WO) or by manually labelling imagery with confidence assigned (UAV/CCO). Method efficacy is compared with respect to spatial coverage, control over survey time/location, spatial resolution, positioning accuracy, and area of digging detected. Personnel hours and up-front costs (e.g. training/equipment), costs for personnel time standardised by shore area, personnel risk, and environmental impact are also compared. Regarding efficacy, CCO imagery had extensive shore coverage compared to UAV and WO, however, assessments are restricted to times/locations with available imagery. Each method's resolution was sufficient to detect digging. WO achieved the highest resolution (on foot), but the lowest positioning accuracy, in contrast to accurate feature delineation on aerial imagery. An additive two-way ANOVA revealed a significantly higher percent area of 'dug' sediment (all confidence levels) recorded by UAV than WO. CCO was the most cost-effective with no fieldwork/equipment costs. UAV had the highest up-front costs, but WO was more costly for personnel hours/km 2 for survey time and digitisation. For all methods, digitisation was the most time-consuming aspect. Compared to WO, UAV achieved rapid shore surveys and the CCO and UAV methods minimise personnel risks. UAV and WO both cause wildlife disturbance, with trampling an additional WO impact. With each method suited to sediment disturbance assessment, selection will depend on resources and objectives and will be aided by this holistic cost-benefit analysis. Cost-effectiveness will improve with evolving regulations that facilitate UAV use and technological developments (e.g. machine learning for disturbance detection) that could significantly expedite imagery analysis and enable broadscale assessments from CCO or satellite imagery., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

The invasive Asian date mussel (Arcuatula senhousia) inhabits diverse global coastal environments, in some circumstances posing significant ecological and economic risks. Recently recorded in the Greater North Sea ecoregion, an established population has not previously been confirmed. Combining historical and field data, we provided baseline information from the UK and recorded colonisation in a variety of habitats. Gonadal development was assessed using the gonadosomatic index (GSI) to determine if an intertidal soft-sediment population is self-sustaining. Arcuatula senhousia records from subtidal muddy/mixed-sediment within a major estuarine system from 2007 to 2016 were also analysed. First detected in 2011, spatial distribution was variable across the years within the subtidal, with individuals found at 4-9 out of 25 sites, and densities per site varying from 10 to 290 individuals per m 2 . The intertidal population was, in part, associated with seagrass (Zostera spp.) and attached to bivalves. In marinas, individuals were attached to concrete tiles, associated with live Mytilus edulis, and to dead Ostrea edulis. Mean GSI from the intertidal population differed across months, peaking in July before declining in September/October, but with high inter-individual variability. Arcuatula senhousia is reproducing and maintaining viable populations. Using a natural capital approach, we identify the potential impacts on Europe's functionally important habitats, fisheries and aquaculture if its spread continues.

Trace elements (TEs) frequently contaminate coastal marine sediments with many included in priority chemical lists or control legislation. These, improved waste treatment and increased recycling have fostered the belief that TE pollution is declining. Nevertheless, there is a paucity of long-term robust datasets to support this confidence. By mining UK datasets (100s of sites, 31 years), we assess sediment concentrations of arsenic (As), cadmium (Cd), chromium (Cr), copper (Cu), iron (Fe), mercury (Hg), nickel (Ni), lead (Pb) and zinc (Zn) and use indices (PI [Pollution], TEPI [Trace Element Pollution] and I geo [Geoaccumulation]) to assess TE pollution evolution. PI and TEPI show reductions of overall TE pollution in the 1980s then incremental improvements followed by a distinct increase (2010-13). Zn, As and Pb I geo scores show low pollution, whilst Cd and Hg are moderate, but with all remaining temporally stable. I geo scores are low for Ni, Fe and Cr, but increasing for Ni and Fe. A moderate pollution I geo score for Cu has also steadily increased since the mid-1990s. Increasing site trends are not universal and, conversely, minimal temporal change masks some site-specific increases and decreases. To capture this variability we strongly advocate embedding sufficient sentinel sites within observation networks. Decreasing sediment pollution levels (e.g. Pb and Hg) have been achieved, but stabilizing I geo and recently increasing TEPI and PI scores require continued global vigilance. Increasing Ni and Fe I geo scores necessitate source identification, but this is a priority for Cu. Local, regional and world analyses indicate substantial 'hidden' inputs from anti-fouling paints (Cu, Zn), ship scrubbers (Cu, Zn, Ni) and sacrificial anodes (Zn) that are also predicted to increase markedly. Accurate TE input assessments and targeted legislation are, therefore, urgently required, especially in the context of rapid blue economic growth (e.g. shipping)., (Copyright © 2020 The Authors. Published by Elsevier Ltd.. All rights reserved.)

The present Data In Brief methodological paper details the acquisition, mining and pre-processing of elemental concentration data in marine sediments (coastal and open sea) of Southern England, presented and discussed in the co-submitted Environment International paper entitled: "Three decades of trace element sediment contamination: the mining of governmental databases and the need to address hidden sources for clean and healthy seas" [1]. Elemental sediment concentration data were obtained from the two main UK environmental sources, i.e. the Environment Agency (EA) and the Marine Environment Monitoring and Assessment National (MERMAN) database managed by the British Oceanographic Data Centre (BODC). The merged database is the result of a rigorous data selection-validation process and provides spatially and temporally extensive records of arsenic (As), cadmium (Cd), chromium (Cr), copper (Cu), iron (Fe), mercury (Hg), nickel (Ni), lead (Pb) and zinc (Zn) concentrations for hundreds of sites over 31 years (1983-2013). Additional records of manganese (Mn), aluminium (Al), lithium (Li), tin (Sn) [and tributyltin (TBT)], barium (Ba), antimony (Sb), boron (B), calcium (Ca), molybdenum (Mo), cobalt (Co), selenium (Se), potassium (K), magnesium (Mg), beryllium (Be), vanadium (V), titanium (Ti), sodium (Na), silver (Ag), thallium (Tl) and strontium (Sr) are also included. The full secondary database is hosted in the Mendeley Data repository and the geo-spatial information to map sites is given in supplementary files to the paper. To provide end-users with the relevant context on spatial and temporal coverage, monitoring statistics are given for the nine trace elements (TEs). Site-specific statistics include: the first and last year of sediment monitoring, the number of years monitored, and minimum, maximum, mean and median numbers of years monitored. Also given are summary data on the number of sites monitored each year, from the first records from 1983 to 2013. For the nine TEs (total and strong acid digestion techniques are considered separately for Cr and Fe), monitoring statistics are presented separately for coastal and open sea sites. Data are relevant to diverse end-users to assess the local and regional contaminant loads and to contextualize anthropogenic threats to benthic systems in multiple locations from the French/English Channel, southern North and Celtic Seas., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships which have or could be perceived to have influenced the work reported in this article., (© 2021 The Authors.)

Polychaetes are vital for evaluating the effects of toxic metals in marine systems, and sensitive molecular biomarkers should be integral to monitoring efforts. However, the few polychaete markers that exist are inconsistent, even within the same species, failing to identify gene expression changes in metal-exposed animals incurring clear metabolic costs. Comparing previously characterised polychaete metal-responsive genes with those of another carefully selected species could identify biomarkers applicable across polychaetes. The ragworm Alitta virens (Sars, 1835) is particularly suited for such comparisons due to its dominance of fully saline coastal areas, widespread distribution, large biomass, and its phylogenetic position relative to other polychaete 'omic' resources. A transcriptome atlas for A. virens was generated and an RNASeq-qPCR screening approach was used to characterise the response to chronic exposures of environmentally relevant concentrations of copper and zinc in controlled mesocosms. Genes presenting dramatic expression changes in A. virens were compared with known metal-responsive genes in other polychaetes to identify new possible biomarkers and assess those currently used. This revealed some current markers should probably be abandoned (e.g. Atox1), while others, such as GST-Omega, should be used with caution, as different polychaete species appear to upregulate distinct GST-Omega orthologues. In addition, the comparisons give some indication of genes that are induced by metal exposure across phylogenetically divergent polychaetes, including a suite of haemoglobin subunits and linker chains that could play conserved roles in metal-stress response. Although such newly identified markers need further characterisation, they offer alternatives to current markers that are plainly insufficient., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Understanding metal toxicity to benthic systems is still an ecotoxicological priority and, although numerous biomarkers exist, a multi-biomarker and endpoint approach with sediment as the delivery matrix combined with life-history relevant exposure timescales is missing. Here we assess potential toxicity by measuring a suite of biomarkers and endpoints after exposing the ecologically important polychaete Alitta(Nereis)virens to sediment spiked with environmentally relevant concentrations of copper and zinc (and in combination) for 3, 6 and 9 months. We compared biomarker and endpoint sensitivity providing a guide to select the appropriate endpoints for the chosen time frame (exposure period) and concentration (relevant to Sediment Quality Guidelines) needed to identify effects for benthic polychaetes such as A. virens. Target bioavailable sediment and subsequent porewater concentrations reflect the global contamination range, whilst tissue concentrations, although elevated, were comparable with other polychaetes. Survival reduced as concentrations increased, but growth was not significantly different between treatments. Metabolic changes were restricted to significant reductions in protein after 9 months exposure across all copper concentrations, and reductions in lipid at high copper concentrations (3 months). Significant changes in feeding behaviour and increases in metallothionein-like protein concentration were limited to the medium and high copper and zinc concentrations, respectively, both after 6 months exposure. Despite data highlighting A. virens' metal tolerance, DNA damage and protein concentrations are the most sensitive biomarkers. Copper and zinc cause biomarker responses at concentrations routinely found in coastal sediments that are characterised as low contamination, suggesting a reappraisal of the current input sources (especially copper) is required., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Using a natural capital framework to inform improvements to water quality and mitigation of climate change requires robust and spatially explicit ecosystem service data. Yet, for coastal habitats this approach is often constrained by a) sufficient and relevant habitat extent data and b) significant variability in baseline assessments used to quantify and value regulatory habitat services. Here, the European Nature Information System (EUNIS) habitat classification scheme is used to map seven key temperate coastal biotopes (littoral sediment, mat-forming green macroalgae, subtidal sediment, saltmarsh, seagrass, reedbeds and native oyster reefs) within the UK's Solent European Marine Site (SEMS). We then estimate the capacity of these biotopes to remove nitrogen (N) and phosphorus (P) and carbon (C), alongside monetary values associated with the resulting benefits. Littoral and sublittoral sediments (including those combined with macroalgae) were the largest contributors to total N, P and C removal, reflecting their large biotope area. However, our results also show considerable differences in relative biotope contributions to nutrient removal depending on how they are analysed and delineated over large spatial scales. When considered at a regional catchment level seagrass meadows, saltmarshes and reedbeds all had considerable N, P and C removal potential. Overall, we estimate that SEMS biotopes provide nutrient reductions and avoided climate damages equivalent to UK £1.1 billion, although this could be nearly £10 billion if water-treatment infrastructure costs and high carbon trading prices are utilised. Despite the variability in the final natural capital evaluations, the substantial regulatory value of N, P and C ecosystem services support a strong rational for restoring temperate coastal biotopes., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Crown Copyright © 2020. Published by Elsevier B.V. All rights reserved.)

Background: Malignant otitis externa is a potentially fatal infection of the skull base. With an ageing population and increasing prevalence of diabetes, the incidence of malignant otitis externa in the British population is rising. To date, there remain no accepted diagnostic criteria, few prognostic indicators and no consensus treatment pathways., Method: A prospective case series was conducted at a tertiary referral teaching hospital., Results: A cohort of susceptible individuals predominates (elderly, male, with immunosuppression and diabetes), with 25 per cent reporting a preceding incident. Otorrhoea, otalgia and canal granulation were the commonest presenting features, alongside positive pseudomonas cultures. No clear markers for predicating disease severity were isolated; however, a high initial haemoglobin A1c level demonstrated a significant moderately positive correlation with length of treatment., Conclusion: A treatment pathway designed to provide a standardised approach to investigation and treatment is proposed, which aims to increase earlier diagnosis, streamline care and facilitate the development of best practice.

Copper and zinc are metals that have been traditionally thought of as past contamination legacies. However, their industrial use is still extensive and current applications (e.g. nanoparticles and antifouling paints) have become additional marine environment delivery routes. Determining a pollutant's genotoxicity is an ecotoxicological priority, but in marine benthic systems putative substances responsible for sediment genotoxicity have rarely been identified. Studies that use sediment as the delivery matrix combined with exposures over life-history relevant timescales are also missing for metals. Here we assess copper and zinc's genotoxicity by exposing the ecologically important polychaete Alitta virens to sediment spiked with environmentally relevant concentrations for 9 months. Target bioavailable sediment and subsequent porewater concentrations reflect the global contamination range for coasts, whilst tissue concentrations, although elevated, were comparable with other polychaetes. Survival generally reduced as concentrations increased, but monthly analyses show that growth was not significantly different between treatments. The differential treatment mortality may have enabled the surviving worms in the high concentration treatments to capture more food thus removing any concentration treatment effects for biomass. Using the alkaline comet assay we confirm that both metals via the sediment are genotoxic at concentrations routinely found in coastal regions and this is supported by elevated DNA damage in worms from field sites. However, combined with the growth data it also highlights the tolerance of A. virens to DNA damage. Finally, using long term (decadal) monitoring data we show stable or increasing sediment concentrations of these metals for many areas. This will potentially mean coastal sediment is a significant mutagenic hazard to the benthic community for decades to come. An urgent reappraisal of the current input sources for these 'old pollutants' is, therefore, required., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Objective: This paper highlights the importance of reporting air-bone gap closure in stapes surgery according to the American Academy of Otolaryngology - Head and Neck Surgery guidelines and reviews compliance in recent years., Methods: A retrospective case series was conducted and the outcomes were reviewed. Closure of the air-bone gap was calculated in 204 adult patients using the aforementioned guidelines. Results were recalculated ignoring the Carhart phenomenon to determine any significant difference. Adherence to guidelines was also reported as a secondary outcome., Results: Ignoring the Carhart phenomenon resulted in 75 per cent over-reporting of successful air-bone gap closure (p < 0.001). Over-reporting occurred in 5.9 per cent of papers, and in 11.8 per cent it was difficult to determine how the results were reached., Conclusion: Despite the existence of clear guidelines, stapes surgery outcomes are still being over-reported as successful. This can lead to incorrect information being provided to patients during the consent process and makes comparative studies difficult.

Bait collection is a multibillion dollar worldwide activity that is often managed ineffectively. For managers to understand the impacts on protected inter-tidal mudflats and waders at appropriate spatial scales macrofaunal surveys combined with video recordings of birds and bait collectors were undertaken at two UK sites. Dug sediment constituted approximately 8% of the surveyed area at both sites and is less muddy (lower organic content) than undug sediment. This may have significant implications for turbidity. Differences in the macrofaunal community between dug and undug areas if the same shore height is compared as well as changes in the dispersion of the community occurred at one site. Collection also induces a 'temporary loss of habitat' for some birds as bait collector numbers negatively correlate with wader and gull abundance. Bait collection changes the coherence and ecological structure of inter-tidal mudflats as well as directly affecting wading birds. However, as β diversity increased we suggest that management at appropriate hectare/site scales could maximise biodiversity/function whilst still supporting collection., (Crown Copyright © 2017. Published by Elsevier Ltd. All rights reserved.)

Objective: The aim of this study is to determine if the cumulative summation test for the learning curve (LC-CUSUM) and the cumulative summation graph (CUSUM) can be used to demonstrate landmark points of competence and maintenance of proficiency in stapes surgery over a continuous time period., Study Design: Retrospective review from January 1999 until August 2014., Setting: Tertiary referral hospital., Patients: All adult patients with confirmed otosclerosis., Intervention(s): Two-hundred and four primary and revision stapedotomy., Main Outcome Measure(s): Learning curves were constructed using the CUSUM and LC-CUSUM. Failure was defined as closure of the ABG >10 dB in less than 10% of patients to demonstrate the landmark point of competency and to highlight any fluctuations over a prolonged period., Results: When the failure rate was defined as closure of the ABG >10 dB, it was not possible to create useful LC-CUSUM and CUSUM graphs, but by redefining the failure rate as > 15 dB, competency was reached at case 43 and maintained with natural fluctuations occurring between cases 137 and 149 and again at case 196., Conclusions: LC-CUSUM and CUSUM are a more robust analytical method of illustrating the learning curve and suggest that the traditional benchmark of closure of the ABG ≤10 dB in more than 90% of patients may need reconsideration. It can also be used as standardized audit tools when monitoring results and used to plan future training programs as they clearly define a point when novice trainees become competent.

Background: Since the development of intratympanic aminoglycoside in the 1950s, otologists have been able to chemically ablate the vestibule. We present the results of using low-dose intratympanic gentamicin to treat Ménière's disease., Method: A retrospective review was performed of all patients who underwent low-dose intratympanic gentamicin therapy over seven years. Data on gender, age, number of procedures, pure tone audiometry and symptom control were analysed., Results: In all, 38 patients underwent low-dose intratympanic gentamicin therapy. These comprised 25 females and 13 males, with an average age of 58.4 years. Hearing was preserved in 87.5 per cent of patients, with no significant difference before and after treatment (p = 0.744). In all, 85.7 per cent of patients had complete or substantial symptom control (classes A and B, respectively)., Conclusion: Low-dose intratympanic gentamicin therapy was effective in controlling the symptoms of Ménière's disease patients, while preserving hearing.

The present study investigates the relationships between copper (Cu) and zinc (Zn) concentrations in sediment, pore water and their bioaccumulation in the polychaete Nereis (Alitta) virens, as well as the importance of site-specific sediment characteristics in that process. Sediment, pore water and N. virens were sampled from seven sites with different pollution histories along the English Channel coast. Results showed that site-specific metal levels and sediment characteristics were important in determining the bioavailability of metals to worms. Significant correlations were found between Cu in the sediment and in the pore water and between Zn in the pore water and in N. virens. Zn from the pore water was thus more readily available from a dissolved source to N. virens than Cu. Data also showed that metal concentrations in N. virens were lower than those found in other closely related polychaetes, indicating that it may regulate tissue concentrations of Cu and Zn., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Objective: The aim of this paper was to propose a guideline for the management of intrinsic facial nerve tumours based on our practice and findings in the literature., Method: A retrospective review of intrinsic facial nerve tumours over the last 15 years was performed. Parameters measured included age, presenting symptoms, pre- and post-treatment hearing and House-Brackmann grading, tumour position, treatment and duration of follow up., Results: A total of 15 patients presented with intrinsic facial nerve tumours over the study period. The most common presenting complaint was facial symptoms (93.3 per cent), followed by hearing loss (46.7 per cent). Three patients with stable facial nerve function (House-Brackmann grades II-III) were treated conservatively. Twelve patients underwent surgery to treat progressive or recurrent symptoms. Facial function was maintained or improved in 60.0 per cent of patients and hearing was preserved in 66.7 per cent., Conclusion: We propose that all stable tumours associated with good facial function of grade III or below should be treated conservatively. For symptomatic or progressive lesions, tailored surgery depending on the tumour site and hearing level should be offered to preserve native nerve function and facial musculature. For patients with prolonged paralysis, tumours can be monitored and other forms of facial reanimation and support offered.

Objective: This study investigated whether patients who remain symptomatic more than a year following idiopathic facial paralysis gain benefit from tailored facial physiotherapy., Methods: A two-year retrospective review was conducted of all symptomatic patients. Data collected included: age, gender, duration of symptoms, Sunnybrook facial grading system scores pre-treatment and at last visit, and duration of treatment., Results: The study comprised 22 patients (with a mean age of 50.5 years (range, 22-75 years)) who had been symptomatic for more than a year following idiopathic facial paralysis. The mean duration of symptoms was 45 months (range, 12-240 months). The mean duration of follow up was 10.4 months (range, 2-36 months). Prior to treatment, the mean Sunnybrook facial grading system score was 59 (standard deviation = 3.5); this had increased to 83 (standard deviation = 2.7) at the last visit, with an average improvement in score of 23 (standard deviation = 2.9). This increase was significant (p < 0.001)., Conclusion: Tailored facial therapy can improve facial grading scores in patients who remain symptomatic for prolonged periods.

It is widely accepted that if well managed, the marine aquarium trade could provide socio-economic stability to local communities while incentivising the maintenance of coral reefs. However, the trade has also been implicated as having potentially widespread environmental impacts that has in part driven developments in aquaculture to relieve wild collection pressures. This study investigates the biodiversity in hobbyist aquaria (using an online survey) and those species currently available from an aquaculture source (commercial data and hobbyist initiatives) in the context of a traffic light system to highlight gaps in aquaculture effort and identify groups that require fisheries assessments. Two hundred and sixty nine species including clown fish, damsels, dotty backs, angelfish, gobies, sea horses and blennies, have reported breeding successes by hobbyists, a pattern mirrored by the European and US commercial organisations. However, there is a mismatch (high demand and low/non-existent aquaculture) for a number of groups including tangs, starfish, anemones and hermit crabs, which we recommend are priority candidates for local stock assessments. Hobbyist perception towards the concept of a sustainable aquarium trade is also explored with results demonstrating that only 40% of respondents were in agreement with industry and scientists who believe the trade could be an exemplar of a sustainable use of coral reefs. We believe that a more transparent evidence base, including the publication of the species collected and cultured, will go some way to align the concept of a sustainable trade across industry stakeholders and better inform the hobbyist when purchasing their aquaria stock. We conclude by proposing that a certification scheme established with government support is the most effective way to move towards a self-regulating industry. It would prevent industry "greenwashing" from multiple certification schemes, alleviate conservation concerns, and, ultimately, support aquaculture initiatives alongside well managed ornamental fisheries.

Objective: To determine the effectiveness of biocements in rebridging isolated incudostapedial erosion., Methods: A review of the use of biocements for isolated incudostapedial joint erosion was performed on publications from 1998 to 2012 available from Medline, Embase and Pubmed. Inclusion criteria were papers published in English, case series or comparative studies with more than 10 patients, isolated incudostapedial erosion through chronic ear disease, minimal air-bone gap less than 20 dB (or air-bone gap less than 10 dB) and follow up for at least one year., Results: In 108 patients, rebridging ossiculoplasty was performed using hydroxyapatite cement. Closure of air-bone gaps less than 20 dB and less than 10 dB was achieved in 80-94.4 per cent and 29-75 per cent, respectively. Glass ionomer cement was used in 318 patients. Closure of air-bone gaps less than 20 dB and less than 10 dB was achieved in 74-94 per cent and 40-76 per cent, respectively., Conclusion: Biocements can be successfully used to close isolated incudostapedial erosions. Larger comparative prospective studies documenting the length of eroded incus and types of reformation of the incudostapedial joint, with standardised reporting, are needed in the future.

We present the case of a 33-year-old man who was admitted with intermittent ataxia, vertigo, and sensorineural hearing loss as a result of a vertebral artery dissection following minor neck trauma. Our aim is to highlight the importance of obtaining magnetic resonance imaging, magnetic resonance angiography, and/or duplex color-flow imaging when presented with a case of fluctuating vertigo and sensorineural hearing loss with side-specific ataxia. Likewise, it is important to obtain the input of neurologists to optimize a patient's prognosis and minimize long-term sequelae.

Objective: To demonstrate that Blu-tack is equally effective at attenuating sound as over-the-counter ear plugs., Methods: Nineteen healthy volunteers had their hearing thresholds assessed before and after the insertion of over-the-counter ear plugs. The results were compared with hearing thresholds following the insertion of Blu-tack. Thresholds were tested at: 0.5, 1, 2, 3, 4, 6 and 8 kHz. The differences were compared, and p values of less than 0.02 were regarded as significant. Using a visual analogue scale, volunteers were asked to assess the comfort and ease of insertion of the ear plugs and Blu-tack, and their peace of mind whilst using the ear plugs and Blu-tack., Results: Blu-tack was less effective at attenuating sound at low frequencies, but was as effective as over-the-counter ear plugs at attenuating sound above 3 kHz. Blu-tack was significantly more comfortable to wear (p = 0.006). There was no difference in terms of ease of insertion and peace of mind., Conclusion: Blu-tack can be regarded as a comfortable alternative to over-the-counter ear plugs for the attenuation of everyday sound.

Introduction: Fourth branchial arch anomalies represent <1% of all branchial anomalies and present as recurrent neck infections or suppurative thyroiditis. Traditionally, management has consisted of treatment of the acute infection followed by hemithyroidectomy, surgical excision of the tract and obliteration of the opening in the pyriform fossa. Recently, it has been suggested that endoscopic obliteration of the sinus tract alone using laser, chemo or electrocautery is a viable alternative to open surgery., Objectives: To determine the results of endoscopic obliteration of fourth branchial arch fistulae in children in our institute., Methods: Retrospective case note review of all children undergoing endoscopic treatment of fourth branchial arch anomalies in the last 7 years at the Royal Manchester Children's Hospital. Patient demographics, presenting symptoms, investigations and surgical technique were analysed. The primary and secondary outcome measures were resolution of recurrent infections and incidence of surgical complications, respectively., Results: In total 5 cases were identified (4 females and 1 male) aged between 3 and 12 years. All presented with recurrent left sided neck abscesses. All children underwent a diagnostic laryngo-tracheo-bronchoscopy which identified a sinus in the apex of the left pyriform fossa. This was obliterated using electrocautery in 1 patient, CO₂ laser/Silver Nitrate chemocautery in 2 patients and Silver Nitrate chemocautery in a further 2 patients. There were no complications and no recurrences over a mean follow-up period of 25 months (range 11-41 months)., Conclusion: Endoscopic obliteration of pyriform fossa sinus is a safe method for treating fourth branchial arch anomalies with no recurrence., (Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.)

Late gametogenic Nereis virens were incubated for up to 2.5 months in environmentally relevant concentrations of copper-spiked sediment. Sequential extraction confirmed that much more labile copper (in actual and percentage terms) was present as spiked concentrations increased, although the residual fractions contained similar amounts across concentrations. This is also reflected in the tissue concentration of the worms which increased in line with the sediment concentrations. Adult mortality was not dependent on the exposure time, but higher concentrations usually induced greater mortality for both sexes. Oocytes were significantly smaller at higher concentrations although pairwise comparisons did not show specific differences. Spawning of males occurred a number of days earlier in the higher concentrations. Differences in the number of embryos developing normally after in vitro fertilizations of oocytes fertilized with sperm from exposed males and non-exposed males showed that sperm were more susceptible to toxicity, but oocytes were also affected at the highest concentration. These results show that there are direct and indirect reproductive consequences of parental exposure to copper with implications for recruitment and subsequent colonization of polluted sediments for this ecologically and commercially important species., (Copyright © 2012 Elsevier B.V. All rights reserved.)

Objective: We discuss the use of balloon dilatation to relieve supraglottic stenosis caused by mucous membrane plasmacytosis., Case Report: A 54-year-old man with a known diagnosis of mucous membrane plasmacytosis presented with dysphonia and worsening airway obstruction which required a tracheostomy. He underwent balloon dilatation of the supraglottic larynx using an angioplasty balloon within sequentially sized endotracheal tubes. This enabled successful decannulation, with minimal re-stenosis at eight-month follow up., Conclusion: To our knowledge, this is the first reported case of supraglottic stenosis caused by plasmacytosis to be successfully treated using this method. We have shown that this minimally invasive technique deals effectively with a complex airway and minimises re-stenosis.

In the last 15 years the diversity of pollutants and routes of impact have increased. However, the polychaete families, species and endpoints investigated have remained fairly constant. Reproductive outputs are more ecologically relevant than adult physiological or biochemical changes. Nevertheless, there remains a paucity of data on the reproductive responses of the popular species to pollutants which limits our ability to understand the true ecological impacts of such contaminants on natural populations. We highlight the current knowledge gaps in our understanding of the impacts of pollutants on the 'model' species' reproductive biology and therefore the potential ecological impacts of such contaminants on their natural populations, and the potential benefits of a wider use of polychaete reproductive endpoints for ecotoxicological assessments. The following priority areas are suggested for inclusion in the polychaete ecotoxicology toolbox: 1. Include reproductive endpoints as assessments of ecotoxicology for the traditional 'model' species and those that have different reproductive traits to ensure broad ecological relevance. 2. Nereids and Arenicola marina should be used to investigate the interaction of pollutants with the endocrine/environmental control of reproduction. 3. Polychaetes are ideal for addressing the under representation of male eco-toxicity effects. 4. Emerging pollutants should be assessed with reproductive endpoints together with the traditional biomarkers. 5. Effects of pollutants on larval behaviour need to be explored considering the limited but equivocal results so far., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

The marine aquarium industry has great potential to generate jobs in low-income coastal communities creating incentives for the maintenance of a healthy coral reef, if effectively managed. In the absence of current monitoring or legislation to govern the trade, baseline information regarding the species, number and source location of animals traded is missing despite being critical for its successful management and sustainability. An industry assessment to establish the number and provenance of species of ornamental polychaetes (sabellids and serpulids) traded was undertaken across UK wholesalers and retailers. Six geographical regions exporting fan worms were identified. Singapore contributed the highest percentage of imports, but of only one worm "type" whereas Bali, the second largest source, supplied five different worm "types". Over 50% of UK retailers were supplied by one wholesaler while the remainder were stocked by a mixture of one other wholesaler and/or direct imports from the source country. We estimate that up to 18,500 ornamental polychaetes (16,980 sabellids and 1,018 serpulids) are sold annually in the UK revealing a drastic underestimation of currently accepted trade figures. Incorrect identification (based on exporting region or visual characteristics) of traded animals exacerbates the inaccuracy in market quantification, although identification of preserved sabellids using published keys proved just as inconclusive with high within-species variability and the potential for new or cryptic species. A re-description of the polychaete groups traded using a combination of molecular and morphological techniques is necessary for effective identification and market quantification. This study provides the first assessment of ornamental polychaetes but more importantly highlights the issues surrounding the collection of baseline information necessary to manage the aquarium trade. We recommend that future management should be community based and site-specific with financial and educational support from NGOs, local governments and industry members.

Study Design: Case study., Discussion: The origin of sulcus vocalis is debatable, it may arise from a congenital or acquired cyst that ruptures leaving a sulcus attached to the deep layer of the lamina propria. This has been hypothesized but never shown before., Conclusion: In this article, we present the first videographic documentation of an intracordal cyst that over time may have become a sulcus vocalis., (Copyright © 2011 The Voice Foundation. Published by Mosby, Inc. All rights reserved.)

Objectives: To compare the difference in ENT and Audiology visits, treatments dispensed and potential savings pre- and post-bone anchored hearing aid (BAHA) insertion in patients with chronic suppurative otitis media exacerbated by behind the ear hearing aids., Design: A retrospective pilot study., Setting: District General Hospital., Participants: All patients who had BAHA inserted from January 2001 to January 2006., Parameters: Age, gender, number of visits per month, treatments per month dispensed from the ENT and Audiology Departments and direct and limited indirect medical costs pre- and post-BAHA insertion., Results: Twelve of 26 (46%) adult patients had BAHA inserted over the 5-year period for CSOM. The male to female ratio was 1 : 3 with a median age of 61 (range 29-81). The number of visits and treatments dispensed per month in the ENT Department fell from a mean of 0.42-0.33 (P < 0.08) and 0.22-0.14 (P < 0.02) respectfully. When the difference in medical cost was taken into account BAHA offered a potential saving of pound 627.80 per patient., Conclusion: Although the initial acquisition of surgical equipment and BAHA sound processors is expensive, there is a reduction in the number of treatments and visits required for patients with chronic suppurative otitis media after BAHA is inserted leading to a reduction in average costs.

Unlabelled: Subglottic cysts (SGC) have long been regarded as a rare cause of airway obstruction but through increased awareness an increase in the number of cases of SGC has been reported., Objective: This paper describes the pathogenesis and management of SGC., Design: Retrospective case series. Ethical approval not sought., Setting: Royal Manchester Children's Hospital., Patients: Two hundred and six new referrals for direct laryngotracheobronchoscopy (DLTB) were identified from records between September 2003 and September 2005., Main Outcomes Measured: Age at birth, sex, length of intubation, presenting symptoms, age at presentation, DLTB findings, interventional procedures, and follow-up DLTBs., Results: Fourteen out of 206 (6.8%) infants were diagnosed as with subglottic cysts. This represented the fourth most common cause of upper airway pathology. Thirteen out of 14 (93%) infants were preterm (26.8 weeks S.D. 25.3-28.3 weeks). All infants had been intubated ranging from 1 to 180 days (median 42 days). The onset of symptoms ranged from 1 to 13 months (median 4.25 months). Initially, 8/14 (57.2%) infants had SGC cysts marsupialised with microforceps. A further six cysts (50%) were decapped between 2 and 4 months and one between 6 and 12 months., Conclusion: The number of cases of SGC has been increasing over the last three decades and represents the fourth most common causes of airway obstruction in our series. There is a delay in onset of symptoms and high rate of recurrence in the first 4 months. It is therefore prudent to reschedule further endoscopic evaluation between 2 and 4 months and after 6 months should the clinical need arise.

The mating behaviour of the signal crayfish, Pacifastacus leniusculus (Dana), has been categorised into seven distinct stages: orientation; contact; seizure; turning; mounting; spermatophore deposition; and dismounting. These categories were used in the development of a bioassay to test whether mature females release a sex pheromone during the breeding season to which males respond. Water conditioned by 1) mature females (MF water), 2) immature females (IF water) and 3) freshwater (C water), were injected through standard aquarium air-stones into tanks containing mature males. The behaviour of the male was recorded on video for 15 minutes before and after injection of each test water. The time that the males spent exhibiting the three behavioural categories of 'quiescent,' 'motile' and 'handling' of the air-stone, were recorded. 'Handling' of the air-stone included the mating behaviours of seizure, mounting, and spermatophore deposition onto the surface of the air-stone. Males exposed to MF water exhibited significantly increased levels of motile activity and handling behaviour, than males exposed to C water or IF water. These results demonstrate for the first time the presence of a sex pheromone, released during the breeding season by mature females, that stimulates courtship and mating behaviour in male P. leniusculus.

Background: Melanoma is an aggressive tumor with a propensity to rapidly metastasize. The PTEN gene encodes a phosphatase with an unusual dual specificity for proteins and lipids. Mutations of PTEN have been found in various human cancers, including glioblastoma, prostate, breast, lung, and melanoma. Here we investigate in vitro the effects of blocking PI3K signaling using adenoviral-delivered PTEN (Ad-PTEN) in cell lines derived from both early- and late-stage melanoma., Materials and Methods: Ad-PTEN transduced melanoma cell lines or normal cells were assayed for cell death, apoptosis, gene expression, invasion and migration, and regulation of angiogenesis., Results: The PTEN locus from RGP and metastatic melanoma cell lines was sequenced; no coding region mutations were found. Adenoviral transfer of PTEN into melanoma cells containing wild-type PTEN alleles led to tumor-specific apoptosis and growth inhibition, with coordinate inhibition of AKT phosphorylation. Ad-PTEN suppressed cell migration by metastatic melanoma cells with concomitant increase in the level of cell surface E-cadherin. Immunohistochemical and confocal analyses localized PTEN to the cytoplasm and demonstrated enrichment at the cell membrane. Ad-PTEN inhibited angiogenesis as demonstrated by the tube formation assay using human vascular endothelial cells., Conclusions: These studies indicate that Ad-PTEN can inhibit tumor cells via multiple mechanisms and has pro-apoptotic, anti-metastatic, and anti-angiogenic properties. Thus, PI3K blockade via Ad-PTEN may be a promising approach for the treatment of early- and late-stage melanoma, even in tumors that do not harbor PTEN mutations.

Background: The mda-7 gene (melanoma differentiation associated gene-7) is a novel tumor suppressor gene. The anti-proliferative activity of MDA-7 has been previously reported. In this report, we analyze the anti-tumor efficacy of Ad-mda7 in a broad spectrum of cancer lines., Materials and Methods: Ad-mda7-transduced cancer or normal cell lines were assayed for cell proliferation (tritiated thymidine incorporation assay, Alamar blue assay, and trypan-blue exclusion assay), apoptosis (TUNEL, and Annexin V staining visualized by fluorescent microscopy or FACs analysis), and cell cycle regulation (Propidium Iodide staining and FACs analysis)., Results: Ad-mda7 treatment of tumor cells resulted in growth inhibition and apoptosis in a temporal and dose-dependent manner. The anti-tumor effects were independent of the genomic status of p53, RB, p16, ras, bax, and caspase 3 in these cells. In addition, normal cell lines did not show inhibition of proliferation or apoptotic response to Ad-mda7. Moreover, Ad-mda7-transduced cancer cells secreted a soluble form of MDA-7 protein. Thus, Ad-mda7 may represent a novel gene-therapeutic agent for the treatment of a variety of cancers., Conclusions: The potent and selective killing activity of Ad-mda7 in cancer cells but not in normal cells makes this vector a potential candidate for cancer gene therapy.

Sex and scents have long been associated. Musk, for example, is a sexual scent that has been used for many years in the perfume industry. In humans, the debate on the existence of sex pheromones continues, whereas in insects their role is well known. Through recent research, we are discovering that such chemicals are equally important in conveying sexual signals between aquatic animals.

PTEN, a putative tumour suppressor gene associated with prostate and other cancers, is known to be located within the chromosomal region 10q23.3. Transcription of the PTEN gives rise to multiple mRNA species. Analyses by Northern blots, using cell lines which express PTEN together with cell lines which have lost the PTEN or carry a truncated version of the gene, has allowed us to demonstrate that the pseudogene is not transcribed. In addition, 3' RACE studies confirmed that the multiple mRNA species arising from the gene probably result from the use of alternative polyadenylation sites. No evidence for tissue- or cell-specific patterns of transcription was found. Analysis by 5' RACE placed the putative site for the start of transcription around 830 bp upstream of the start codon. A map of the location of the PTEN gene with a series of overlapping YAC, BAC and PACs has been constructed and the relative position of eight microsatellite markers sited. Two known and one novel marker have been positioned within the gene, the others are in flanking regions. The more accurate location of these markers should help in future studies of the extent of gene loss. Several polymorphisms were also identified, all were within introns. Four of the common polymorphisms appear to be linked. In blood, DNA from 200 individuals, including normal, BPH and prostate cancer patients, confirmed this link. Only two samples of 200 did not carry the linked haplotype, both were patients with advanced prostate cancer. It is possible that such rearrangements within PTEN could be evidence of predisposition to prostate cancer in this small number of cases.

Inhibitors of angiogenesis hold potential in the treatment of cancer and other diseases where the disease is caused or maintained by the inappropriate growth of blood vessels. In the present study, a novel inhibitor of angiogenesis was synthesized by covalently linking a nonanticoagulating derivative of heparin, heparin adipic hydrazide (HAH), by an acid-labile bond to the antiangiogenic steroid, cortisol. The rationale was that the heparin derivative, which binds to sulfated polyanion receptors on endothelial cells, should concentrate the steroid on the surface of vascular endothelial cells. Endocytosis of the conjugate and decomposition of the acid-labile linkage inside lysosomes and other acidic intracellular compartments should then lead to release of the cortisol and expression of its antiproliferative activity. Analysis of the stability of HAH-cortisol showed that it was stable at pH 7.4 and broke down rapidly (t1/2 15 min) at pH 4.8 at 37 degrees C. Treatment of murine pulmonary capillary endothelial cells with HAH-cortisol at 10(-5) M (with respect to cortisol) suppressed their DNA synthesis by 50% and inhibited their migration into wounded areas of confluent monolayers. HAH-cortisol at 10(-4) M (with respect to cortisol) did not suppress the DNA synthesis of Lewis lung carcinoma cells. Daily i.p. injections of HAH-cortisol into mice bearing s.c. sponge implants retarded vascularization of the sponge, and injections directly into the sponge abolished vascularization for as long as the injections were continued. Daily i.v. injections of HAH-cortisol at doses causing no apparent toxicity retarded the growth of solid s.c. Lewis lung carcinomas in mice by up to 65%. In all of these assays, equivalent treatments with a mixture of the HAH plus cortisol was significantly less effective. The antiproliferative effect of HAH-cortisol on endothelial cells appeared independent of the glucocorticoid activity of the steroid since HAH conjugated to 5 beta-pregnane-3 alpha,17 alpha,21-triol-20-one, a steroid lacking glucocorticoid or mineralocorticoid activity, was even more effective at inhibiting DNA synthesis by murine pulmonary capillary endothelial cells than was HAH-cortisol. In conclusion, HAH-cortisol represents the prototype of a new class of angiogenesis inhibitors for the treatment of cancer and other angiogenic diseases.

An immunotoxin consisting of ricin A chain linked to the monoclonal antibody M-T151, recognising the CD4 antigen, was weakly toxic to the human T-lymphoblastoid cell line CEM in tissue culture. The incorporation of [3H]leucine by CEM cells was inhibited by 50% at an M-T151--ricin-A-chain concentration (IC50) of 4.6 nM compared with an IC50 of 1.0 pM for ricin. In contrast, immunotoxins made by linking intact ricin to M-T151 in such a way that the galactose-binding sites of the B chain subunit were either blocked sterically by the antibody component or were left unblocked, were both powerfully cytotoxic with IC50 values of 20-30 pM. The addition of ricin B chain to CEM cells treated with M-T151--ricin-A-chain enhanced cytotoxicity by only eight-fold indicating that isolated B chain potentiated the action of the A chain less effectively than it did as an integral component of an intact ricin immunotoxin. Ricin B chain linked to goat anti-(mouse immunoglobulin) also potentiated weakly. Lactose completely inhibited the ability of isolated ricin B chain to potentiate the cytotoxicity of M-T151--ricin-A-chain and partially (3- to 4-fold) inhibited the cytotoxicity of the blocked and non-blocked ricin immunotoxins. Thus, in this system, the galactose-binding sites of the B chain contributed to cell killing regardless of whether isolated B chain was associated with the A chain immunotoxin or was present in blocked or non-blocked form as part of an intact ricin immunotoxin. The findings suggest that the blocked ricin immunotoxin may become unblocked after binding to the target antigen to re-expose the cryptic galactose-binding sites. However, the unblocking cannot be complete because the maximal inhibition of [3H]leucine incorporation by the blocked immunotoxin was only 80% compared with greater than 99% inhibition by the non-blocked immunotoxin.