Perspectives of Healthcare Professionals on the Management and Treatment of Advanced Ovarian Cancer in the UK: Results From the KNOW-OC Survey

AIMS

New treatment options for advanced ovarian cancer have the potential to significantly change the treatment pathway in the UK. Understanding the structures and responsibilities of multidisciplinary teams/tumour boards (MDT) and regional variations will enable services to adapt more effectively to these changes.

MATERIALS AND METHODS

The KNOW-OC survey was conducted in 2020 to understand the views of a selected group of 66 healthcare professionals (HCPs) involved in advanced ovarian cancer care in UK hospitals.

RESULTS

The results showed that MDT involvement in the management of advanced ovarian cancer varied depending on pathway stage and line of relapse, with 98.5% of HCPs responding that the MDT was involved in decisions at initial presentation, but only 40.9% for patients with multiple relapses. The MDT was mostly responsible for determining whether the patients would undergo primary or interval cytoreductive surgery according to 75.8% of respondents, and most HCPs (80.3%) stated that tumour dissemination patterns were the most important factor influencing this decision. The most commonly assessed biomarkers at the time of the survey were CA125, gBRCA and tBRCA. Homologous recombination deficiency was viewed as the second most important factor for determining prognosis, but few centres had access to testing at the time of survey completion. The use of active surveillance was expected to decrease in favour of first-line targeted therapies. Nearly all (98.5%) HCPs agreed there is a role for secondary cytoreductive surgery for the treatment of recurrence (for carefully selected patients).

CONCLUSIONS

The results highlighted UK-specific geographical variation in the views of HCPs on MDT involvement and specific practices, such as molecular biomarker testing, and the overall treatment approach. Together, these findings improve the understanding of reported clinical practice across the UK for ovarian cancer and provide insight into decision-making associated with updates to recommendations for best practice (e.g. European Society for Medical Oncology/European Society of Gynaecological Oncology consensus statements) and the introduction of new treatment options.

Viral Respiratory Epidemic Modeling of Societal Segregation Based on Vaccination Status

BACKGROUND

Societal segregation of unvaccinated people from public spaces has been a novel and controversial coronavirus disease 2019 (COVID-19)-era public health practice in many countries. Models exploring potential consequences of vaccination-status-based segregation have not considered how segregation influences the contact frequencies in the segregated groups. We systematically investigate implementing effects of segregation on population-specific contact frequencies and show this critically determines the predicted epidemiological outcomes, focusing on the attack rates in the vaccinated and unvaccinated populations and the share of infections among vaccinated people that were due to contacts with infectious unvaccinated people.

METHODS

We describe a susceptible-infectious-recovered (SIR) two-population model for vaccinated and unvaccinated groups of individuals that transmit an infectious disease by person-to-person contact. The degree of segregation of the two groups, ranging from zero to complete segregation, is implemented using the like-to-like mixing approach developed for sexually transmitted diseases, adapted for presumed severe acute respiratory syndrome coronavirus 2 (SARS‑CoV‑2) transmission. We allow the contact frequencies for individuals in the two groups to be different and depend, with variable strength, on the degree of segregation.

RESULTS

Segregation can either increase or decrease the attack rate among the vaccinated, depending on the type of segregation (isolating or compounding), and the contagiousness of the disease. For diseases with low contagiousness, segregation can cause an attack rate in the vaccinated, which does not occur without segregation.

INTERPRETATION

There is no predicted blanket epidemiological advantage to segregation, either for the vaccinated or the unvaccinated. Negative epidemiological consequences can occur for both groups.

Predictions from standard epidemiological models of consequences of segregating and isolating vulnerable people into care facilities

OBJECTIVES

Since the declaration of the COVID-19 pandemic, many governments have imposed policies to reduce contacts between people who are presumed to be particularly vulnerable to dying from respiratory illnesses and the rest of the population. These policies typically address vulnerable individuals concentrated in centralized care facilities and entail limiting social contacts with visitors, staff members, and other care home residents. We use a standard epidemiological model to investigate the impact of such circumstances on the predicted infectious disease attack rates, for interacting robust and vulnerable populations.

METHODS

We implement a general susceptible-infectious-recovered (SIR) compartmental model with two populations: robust and vulnerable. The key model parameters are the per-individual frequencies of within-group (robust-robust and vulnerable-vulnerable) and between-group (robust-vulnerable and vulnerable-robust) infectious-susceptible contacts and the recovery times of individuals in the two groups, which can be significantly longer for vulnerable people.

RESULTS

Across a large range of possible model parameters including degrees of segregation versus intermingling of vulnerable and robust individuals, we find that concentrating the most vulnerable into centralized care facilities virtually always increases the infectious disease attack rate in the vulnerable group, without significant benefit to the robust group.

CONCLUSIONS

Isolated care homes of vulnerable residents are predicted to be the worst possible mixing circumstances for reducing harm in epidemic or pandemic conditions.

Production of large, defined genome modifications in rats by targeting rat embryonic stem cells

Rats were more frequently used than mice to model human disease before mouse embryonic stem cells (mESCs) revolutionized genetic engineering in mice. Rat ESCs (rESCs) were first reported over 10 years ago, yet they are not as frequently used as mESCs. CRISPR-based gene editing in zygotes is widely used in rats but is limited by the difficulty of inserting or replacing DNA sequences larger than about 10 kb. We report here the generation of germline-competent rESC lines from several rat strains. These rESC lines maintain their potential for germline transmission after serial targeting with bacterial artificial chromosome (BAC)-based targeting vectors, and CRISPR-Cas9 cutting can increase targeting efficiency. Using these methods, we have successfully replaced entire rat genes spanning up to 101 kb with the human ortholog.

An initial investigation of serum cytokine levels in patients with gadolinium retention

Objective

To determine whether individuals with proposed gadolinium deposition disease (GDD) have elevated serum levels of pro-inflammatory and pro-fibrotic cytokines, and whether specific cytokines are correlated with certain symptoms.

Materials and Methods

Twenty-four participants recruited between May 2016 and June 2017 met GDD diagnostic criteria. The 64 control subjects provided serum samples before prophylactic flu vaccination. Serum cytokine levels were obtained with Luminex serum cytokine assay using eBiosciences/Affymetrix human 62-plex kits. Wilcoxon rank-sum tests were performed to assess the difference between the median fluorescence intensity values for the participants and the control group. Generalized linear models were built to evaluate the association between each cytokine of interest and selected participant symptoms.

Results

Serum levels of 14 cytokines, including nine pro-inflammatory cytokines, were statistically significantly elevated compared to controls (p ≤ 0.05). Hypotheses regarding pro-fibrotic cytokines and cytokine links to specific symptoms' intensity were not confirmed.

Conclusion

The statistically significantly elevated cytokines may be markers of susceptibility to GDD or agents of symptom induction. These findings suggest that individuals developing symptoms characteristic of GDD after a contrast-assisted magnetic resonance imaging should be studied to investigate whether gadolinium retention and elevated cytokines may be related to their symptoms.

0952 Parent-Child Perceptions About Healthy Sleep Promotion in a Mobile Health Sleep Extension Intervention

Introduction

Over half of school-aged children sleep insufficiently and sleep promoting interventions are urgently needed. To effectively promote pediatric sleep health, it is critical to obtain feedback from youth and their families about acceptable intervention strategies. This qualitative study examined perceptions about healthy sleep promotion in parent-child dyads participating in a mobile health sleep extension intervention.

Methods

A total of 26 parent-child dyads (child mean age 11 years, SD = 0.67; 46% non-Latinx White; 19% Black) participated in a mobile intervention to extend child sleep duration over 11 weeks (2-week baseline; 7-week intervention; 2-week follow-up). Participants wore a FitBit during the study, were provided with a sleep duration goal, and received general sleep health-promoting electronic messages using the University of Pennsylvania’s Way to Health platform. Following the intervention, parents and their children separately completed a semi-structured telephone interview to capture perceptions of the intervention strategies. Three coders developed a codebook using an inductive approach to identify emergent themes and conducted coding in NVivo.

Results

Emergent themes fell into domains of intervention acceptability/feasibility and barriers. Mobile messaging about the child’s sleep duration goal was well-received, although child participants in particular desired more personalized messaging, with sleep promotion targeted to their specific sleep habits. Parents and children both discussed ancillary benefits to intervention participation, including an enhanced focus on sleep. Barriers to sleep extension during the intervention and maintenance of any gains post-intervention were related to: competing child academic, social, and extracurricular demands; family factors (work schedules; family rules and norms); and the challenges of limiting ubiquitous electronic devices.

Conclusion

Despite high parent-child acceptability of a mobile child sleep extension intervention, individual and contextual barriers may limit long-term adherence. Tailoring healthy sleep messages to target these factors could improve sustained benefits to child sleep.

Support

Sleep Research Society Foundation and K23HD094905 (AAW); NIH/NCATS UL1TR001878 (JAM and DFD) and K01HL123612 (JAM).

Self-organization and time-stability of social hierarchies

The formation and stability of social hierarchies is a question of general relevance. Here, we propose a simple generalized theoretical model for establishing social hierarchy via pair-wise interactions between individuals and investigate its stability. In each interaction or fight, the probability of "winning" depends solely on the relative societal status of the participants, and the winner has a gain of status whereas there is an equal loss to the loser. The interactions are characterized by two parameters. The first parameter represents how much can be lost, and the second parameter represents the degree to which even a small difference of status can guarantee a win for the higher-status individual. Depending on the parameters, the resulting status distributions reach either a continuous unimodal form or lead to a totalitarian end state with one high-status individual and all other individuals having status approaching zero. However, we find that in the latter case long-lived intermediary distributions often exist, which can give the illusion of a stable society. As we show, our model allows us to make predictions consistent with animal interaction data and their evolution over a number of years. Moreover, by implementing a simple, but realistic rule that restricts interactions to sufficiently similar-status individuals, the stable or long-lived distributions acquire high-status structure corresponding to a distinct high-status class. Using household income as a proxy for societal status in human societies, we find agreement over their entire range from the low-to-middle-status parts to the characteristic high-status "tail". We discuss how the model provides a conceptual framework for understanding the origin of social hierarchy and the factors which lead to the preservation or deterioration of the societal structure.

A retrospective observational study of people with Type 1 diabetes with self-reported severe hypoglycaemia reveals high level of ambulance attendance but low levels of therapy change and specialist intervention

AIM

To evaluate the impact of severe hypoglycaemia on NHS resources and overall glycaemic control in adults with Type 1 diabetes.

METHODS

An observational, retrospective study of adults (aged ≥ 18 years) with Type 1 diabetes reporting one or more episodes of severe hypoglycaemia during the preceding 24 months in 10 NHS hospital diabetes centres in England and Wales. The primary outcome was healthcare resource utilization associated with severe hypoglycaemia. Secondary outcomes included demographic and clinical characteristics, diabetes control and pathway of care.

RESULTS

Some 140 episodes of severe hypoglycaemia were reported by 85 people during the 2-year observation period. Ambulances were called in 99 of 140 (71%) episodes and Accident and Emergency attendance occurred in 26 of 140 (19%) episodes, whereas 29 of 140 (21%) episode required no immediate help from healthcare providers. Participants attended a median of 5 (range 0-58) diabetes clinic consultations during the observation period; 13% (70 of 552) of all consultations were severe hypoglycaemia-related. Of the HbA1c measurements recorded closest prior to severe hypoglycaemia (n = 119), only 7 of 119 measurements were < 48 mmol/mol (< 6.5%) and mean HbA1c was 70 (sd 19) mmol/mol (8.5%, sd 1.7%). Some 119 changes to diabetes treatment were recorded during the observation period (median/person 0;, range 0-11), of which 52 of 119 changes (44%) followed severe hypoglycaemic events.

CONCLUSIONS

We observed a high level of ambulance service intervention but surprisingly low levels of hypoglycaemia follow-up, therapy change and specialist intervention in people self-reporting severe hypoglycaemia. These results suggest there may be important gaps in care pathways for people with Type 1 diabetes self-reporting severe hypoglycaemia.

The Prison and the Inmate's Conception of Legal Justice

Existing prison programs fail to provide opportunities for the offender to participate in meaningful democratic experiences. The Niantic Project sought to create a prison environment which would avoid the pitfalls of conventional correctional settings. The goals of the proposed alternative were to create a setting which would actively stimulate the sociolegal thinking of the inmates involved and would aid inmates in leading successful lives following release from the institution.

Genomic prediction in CIMMYT maize and wheat breeding programs

Genomic selection (GS) has been implemented in animal and plant species, and is regarded as a useful tool for accelerating genetic gains. Varying levels of genomic prediction accuracy have been obtained in plants, depending on the prediction problem assessed and on several other factors, such as trait heritability, the relationship between the individuals to be predicted and those used to train the models for prediction, number of markers, sample size and genotype × environment interaction (GE). The main objective of this article is to describe the results of genomic prediction in International Maize and Wheat Improvement Center's (CIMMYT's) maize and wheat breeding programs, from the initial assessment of the predictive ability of different models using pedigree and marker information to the present, when methods for implementing GS in practical global maize and wheat breeding programs are being studied and investigated. Results show that pedigree (population structure) accounts for a sizeable proportion of the prediction accuracy when a global population is the prediction problem to be assessed. However, when the prediction uses unrelated populations to train the prediction equations, prediction accuracy becomes negligible. When genomic prediction includes modeling GE, an increase in prediction accuracy can be achieved by borrowing information from correlated environments. Several questions on how to incorporate GS into CIMMYT's maize and wheat programs remain unanswered and subject to further investigation, for example, prediction within and between related bi-parental crosses. Further research on the quantification of breeding value components for GS in plant breeding populations is required.

Classical nucleation theory with a radius-dependent surface tension: a two-dimensional lattice-gas automata model

The constant surface tension assumption of the Classical Nucleation Theory (CNT) is known to be flawed. In order to probe beyond this limitation, we consider a microscopic, two-dimensional Lattice-Gas Automata (LGA) model of nucleation in a supersaturated system, with model input parameters E(ss) (solid particle-to-solid particle bonding energy), E(sw) (solid particle-to-water bonding energy), η (next-to-nearest-neighbor bonding coefficient in solid phase), and C(in) (initial solute concentration). The LGA method has the advantages of easy implementation, low memory requirements, and fast computation speed. Analytical results for the system's concentration and the crystal radius as functions of time are derived and the former is fit to the simulation data in order to determine the equilibrium concentration. The "Mean First-Passage Time" technique is used to obtain the nucleation rate and critical nucleus size from the simulation data. The nucleation rate and supersaturation data are evaluated using a modification to the CNT that incorporates a two-dimensional radius-dependent surface tension term. The Tolman parameter, δ, which controls the radius dependence of the surface tension, decreases (increases) as a function of the magnitude of E(ss) (E(sw)), at fixed values of η and E(sw) (E(ss)). On the other hand, δ increases as η increases while E(ss) and E(sw) are held constant. The constant surface tension term of the CNT, Σ(0), increases (decreases) with increasing magnitudes of E(ss) (E(sw)) at fixed values of E(sw) (E(ss)) and increases as η is increased. Σ(0) increases linearly as a function of the change in energy during an attachment or detachment reaction, |ΔE|, however, with a slope less than that predicted for a crystal that is uniformly packed at maximum density. These results indicate an increase in the radius-dependent surface tension, Σ, with respect to increasing magnitude of the difference between E(ss) and E(sw).

P1-07-12: Assessment of Real World HER2 Status by Immunohistochemistry (IHC) and Fluorescence In Situ Hybridization (FISH) in Breast Cancers: Comparison with HERmark®, a Validated Quantitative Measure of HER2 Protein Expression

Background: Accurate assessment of the HER2 status is critical in determining appropriate therapy for patients with invasive breast cancer. ASCO/CAP HER2 testing guidelines caution that up to 20% of routine HER2 testing by IHC/FISH may be unreliable (Wolff et al. JCO 2007;25:118). The HERmark assay is a novel quantitative HER2 protein measurement for determining HER2 status in breast cancer. Central HER2 testing showed high concordance (96-98%) with HERmark for positive and negative categories when equivocal subsets were excluded (Huang et al. Am J Clin Pathol 2010;134:303; Joensuu et al, 2008 SABCS, abstract 2071). In this study, we examined concordance between HERmark and routine HER2 testing by IHC and FISH from “real world” formalin-fixed, paraffin-embedded (FFPE) breast cancers submitted commercially for HERmark testing.

Methods: 717 HERmark results on FFPE breast cancers tested from 2008 to 2010 and corresponding HER2 IHC/FISH results were reviewed. The IHC and FISH results, per pathology reports submitted at the time of HERmark testing, were compared to HERmark categorical (negative, equivocal, positive) results.

Results: 590 (419) samples had IHC (FISH) and HERmark results available. Of these cases, 92% (94%) were either negative or equivocal by IHC (FISH). The HERmark testing reported 33% HERmark negative, 33% HERmark equivocal and 34% HERmark positive. Comparisons of HER2 status by IHC and FISH vs. HERmark are detailed in Table 1.

Adversity, Emotional Arousal, and Problem Behaviour in Adolescence: The Role of Non-Verbal Cognitive Ability as a Resilience Promoting Factor

BACKGROUND

  To test whether emotional arousal mediates the moderator effect of non-verbal cognitive ability on the association between cumulative contextual risk (number of proximal and distal adverse life events) and adolescent problem behaviour.

METHOD

  Data from a UK community sample of secondary school aged children were used. The study sample comprised 207 children with a mean age of 13.44 years (SD = 1.45). Problem behaviour was assessed with the Strengths and Difficulties Questionnaire, non-verbal cognitive ability was assessed with Raven's Standard Progressive Matrices Plus, and emotional arousal was measured with the Acting Out Emotions Scale of the Emotion Awareness Questionnaire. Adjustment was made for gender, age, family structure, and socio-economic disadvantage.

RESULTS

  Non-verbal cognitive ability moderated the effect of cumulative contextual risk on overall problem behaviour, and emotional arousal mediated this moderator effect. That is, risk predicted emotional arousal, which predicted overall problem behaviour, but emotional arousal was more strongly related to overall problem behaviour among children of low non-verbal cognitive ability than among children of high non-verbal cognitive ability.

CONCLUSIONS

  These findings are important for both theory development and intervention design. They advance theory because they suggest that non-verbal cognitive ability buffers the effect of risk on overall problem behaviour by strengthening control over emotions. They have implications for intervention design because they suggest that interventions carried out to enhance children's emotion regulation skills in the presence of multiple adversity might be more effective if they target children who score low on non-verbal cognitive ability.

Mouse fibroblast cell adhesion studied by neutron reflectometry

Neutron reflectometry (NR) was used to examine live mouse fibroblast cells adherent on a quartz substrate in a deuterated phosphate-buffered saline environment at room temperature. These measurements represent the first, to our knowledge, successful visualization and quantization of the interface between live cells and a substrate with subnanometer resolution using NR. NR data, attributable to the adhesion of live cells, were observed and compared with data from pure growth medium. Independently of surface cell density, the average distance between the center of the cell membrane region and the quartz substrate was determined to be approximately 180 A. The membrane region ( approximately 80 A thick) contains the membranes of cells that are inhomogeneously distributed or undulating, likely conforming to the nonplanar geometry of the supporting adherence proteins. A second region of cell membranes at a greater distance from the substrate was not detectable by NR due to the resolution limits of the technique employed. Attachment of the live cell samples was confirmed by interaction with both distilled water and trypsin. Distinct changes in the NR data after exposure indicate the removal of cells from the substrate.

Optimization of cutaneous electrically mediated plasmid DNA delivery using novel electrode

The easy accessibility of skin makes it an excellent target for gene transfer protocols. To take advantage of skin as a target for gene transfer, it is important to establish an efficient and reproducible delivery system. Electroporation is an established technique for enhancing plasmid delivery to many tissues in vivo. A critical component of this technique is the electrode configuration. Electroporation parameters were optimized for transgene expression with minimal tissue damage with a novel electrode. The highest transgene expression and efficiency of individual cell transformation with minimal damage was produced with eight 150 ms pulses at field strength of 100 V/cm. This electrode design offers the potential for easier and more reproducible electrically mediated cutaneous plasmid delivery than the simple electrodes currently commercially available. This electrode can be a valuable tool in determining the applicability of electrically mediated cutaneous gene transfer.

Characteristics of blast furnace slag leachate produced under reduced and oxidized conditions

A laboratory study was conducted to determine the environmental conditions necessary to reproduce leachates observed emerging from blast furnace slag acting as the foundation of highways in northwest Indiana. The leachates in the field are often highly alkaline with a pungent sulfur odor, a distinct green or milky-white in color, and sulfate concentrations exceeding 2,000 mg/L. Slag was equilibrated in the laboratory under both oxidized and anoxic environments and at various slag:water ratios. Constant anoxic conditions were required to produce to green colors in the slag, but high sulfate concentrations were observed only when the suspensions were fully oxidized. Leachate from the study site appears to form as a result of a series of complex chemical reactions including fluctuating oxidized and reduced conditions.

Genetic Aspects of Growth of Holstein-Friesian Dairy Cows from Birth to Maturity

In general, genetic selection is applied after first calving to traits that manifest themselves during the animal's productive life, mostly during the early part of productive life. This selection policy has had undesirable correlated responses in other economically important traits, such as health and fertility, and may also have had an effect on the growth of animals both during productive life and before first calving. In this study, we analyzed the growth trajectory of dairy heifers that had been selected for maximum production of combined fat and protein (measured in kg; select line) or for average production (control line) in the United Kingdom. Before first calving, these divergent lines were managed as a single group. Select line heifers grew faster than did control line heifers. They were also heavier at first calving, but by the end of 3 lactations, the lines were not significantly different in live weight. Selection primarily for yield and for other traits has led to heifers that grow faster and reach higher growth rates earlier in life. A genetic analysis of birth, weaning, and calving weights yielded heritability estimates of 0.53 (birth weight), 0.45 (weaning weight), and 0.75 (calving weight). Confidence intervals for the genetic correlations between the traits indicated that these BW traits are not under the same genetic control.

Comparisons of PBDE composition and concentration in fish collected from the Detroit River, MI and Des Plaines River, IL

Polybrominated diphenyl ethers (PBDEs) were identified in fish collected from the Detroit River, MI and Des Plaines Rivers, IL. In the Detroit River fish, carp and large mouth bass, the congener patterns were dominated by the 2,2',4,4'-tetrabromo (BDE-47) congener, however, in Des Plaines River carp the dominant isomers were the heptabromo congeners BDE-181 and BDE-183 and lesser amounts of another heptabromo congener, BDE-190, and two hexabromo congeners, BDE-154 and BDE-153. Three possible sources exist for these less-commonly identified PBDE congeners: (a) waste discharge from manufacturing or discarded products near the river, (b) public owned treatment work (POTW) effluents which constitute more than 75% of the flow in the Des Plaines River, (c) or formation of these congeners by debromination of in-place deposits of decabromodiphenyl ether. Average concentration totals (sum of concentrations for seven of the dominant PBDE congeners) were similar on a wet weight bases for the carp (5.39 ng/g wet weight) and large mouth bass (5.25 ng/g) in the Detroit River samples; however, the bass were significantly higher, p = 0.01, when compared on a lipid basis (bass--163 ng/g vs. carp--40.5 ng/g lipid weight). Some of the PBDE congeners were positively correlated with increasing lipid levels in both fish species. Average total PBDE concentrations in the carp from the Des Plaines River (12.48 ng/g wet weight) were significantly higher, p = 0.01, than in carp from the Detroit River. The residues were isolated using standard organochlorine methods for fish and analyzed using gas chromatography/mass spectrometry-negative chemical ionization methods.

Toxicity of anticancer agents mediated by electroporation in vitro

Electroporation is a physical event that temporarily reduces cell membrane barrier properties. Diminished membrane barrier properties are achieved by exposing cells to pulsed electric fields. When a cell has been treated with electric fields it is possible for extracellular agents to gain access to the cell interior. This process has been used in vivo to increase the uptake of chemotherapeutic agents by tumor cells which results in dramatically higher response rates than when drug is used alone. This type of treatment is called electrochemotherapy (ECT); bleomycin is most often used as the drug for this type of treatment. It was hypothesized that electroporation could be used to augment the cytotoxicity of other anticancer agents. Therefore, this study was performed in order to screen 44 different combinations of drug and cell type in vitro to identify drugs that may have higher cytotoxicity when combined with electroporation. Results from seven cell types indicate that the IC50 of bleomycin can be reduced by a factor of 100-5000 when electroporation is used to facilitate internalization. The IC50 values of cisplatin and carboplatin could be reduced by factors ranging from 3 to 13 in six different cell lines as a result of electroporation. These IC50 reductions in multiple cell lines suggest that cisplatin and carboplatin may be effective in vivo as part of ECT treatment.

Properties of an enzyme-based low-level iodine disinfectant

An enzyme-based iodine (EBI) disinfectant that continuously generates free molecular iodine in a controlled fashion was developed and evaluated for use in disinfecting flexible fibreoptic endoscopes (FFEs). EBI is a powder concentrate that produces iodine from sodium iodide and calcium peroxide when catalyzed by horseradish peroxidase. After dissolution in water, it delivers relatively high concentrations of free molecular iodine (> 15 ppm) at relatively low concentrations of total iodine (30-40 ppm). It demonstrates the ability to function as an effective low level iodine disinfectant by rapidly inactivating bacteria, fungi and viruses. A unique feature of the EBI system is the ability to reoxidize reduced iodine which results in a constant level of active (free molecular) iodine during use. EBI inactivates Mycobacterium bovis var BCG more rapidly than 2% glutaraldehyde (Cidex-7). Its sporicidal activity, however, was found to be slower than the aldehyde formulation. The qualification of EBI for use as a practical disinfectant was shown by its negligible toxicity in dermal, ocular, oral and inhalation studies on animals, which is attributed to the low level of total iodine in the solution.

Control of the amount of free molecular iodine in iodine germicides

Horseradish peroxidase has been used to generate iodine compositions that comprised principally free molecular iodine. The concentration of free molecular iodine in these enzyme-based compositions ranged from 44 to 63% of the thiosulphate titratable iodine; this is substantially higher than the corresponding value for the povidone-iodine preparation betadine. The biocidal efficacy of these compositions was proportional to the concentration of free molecular iodine. Iodine compositions with relatively low total iodine concentrations but high levels of free molecular iodine (20-175 ppm) killed Staphylococcus aureus and spores of Bacillus subtilis more rapidly than betadine. The effects of normal saline and these enzyme-based iodine compositions on the rate of epidermal regeneration in superficial swine wounds were comparable. These results suggest that an effective germicide containing a high level of molecular iodine need not be irritating or toxic.

Derbyshire thirteen working together

A group of 13 practices from Derbyshire saw the QDAs as a chance to improve upon their total service quality. Working in groups, and with their FHSA, they succeeded in improving their service and empowering their practice teams.

The dosimetry of iodine-123-labeled TISCH: a SPECT imaging agent for the D1 dopamine receptor

TISCH is an iodinated D1 specific dopamine receptor antagonist that may be useful as a SPECT imaging agent. This report documents its pharmacological safety in animals and its radiation dosimetry in humans. The dose of radiation that 123I-TISCH delivered to seven healthy subjects was estimated with the absorbed fraction technique. Conjugate images of the body were serially acquired for up to 24 hr after the administration of a known amount of activity. The count rates in the organs that could be visualized were measured on each image. These count rates were corrected for attenuation with 123I transmission scans. The doses to the other organs that did not take up enough activity to be visualized on the images were estimated with established models. The dosimetry was calculated for each subject individually before the results were averaged. Rapid biological washout minimizes the radiation exposure to most organs. The dose to the large bowel is limiting in healthy volunteers. The proximal colon receives about 0.67 rad/mCi (180 microGy/MBq) or about 5 rads for every 7.5 mCi of TISCH injected. This low radiation burden should make it feasible to study the D1 dopamine receptor in patients who have neuropsychiatric disorders before and after treatment.