Identifying research priorities for infection prevention and control. A mixed methods study with a convergent design

Background

Meaningful research creates evidence for Infection Prevention and Control (IPC) practice.

Aim

To establish Infection Prevention Society (IPS) members' research priorities to support future research projects.

Methods

A mixed methods convergent parallel design incorporating a cross-sectional survey of IPS members (2022-2023), and focus group findings from the IPS Consultative Committee, (October 2022). Quantitative data were analysed using descriptive statistics. Qualitative data were transcribed verbatim, entered into NVivo 12, and analysed using a thematic analysis approach.

Findings/Results

132 IPS members responded to the survey, including 120 (90.9%) nurses. The three most prevalent priorities were: Quality Improvement and Patient Safety (n = 84, 16.1%); IPC Training and Education (n = 77, 14.8%); and IPC Evidence-based Guidelines (n = 76, 14.6%). Analysis of the focus group transcripts identified six emergent themes 'Patient Centred Care', 'Training and Education', 'IPC Role and Identity', 'IPC Leadership', 'IPC is Everyone's Responsibility', and 'Research Activity'. Triangulation of findings demonstrated concordance between quantitative and qualitative findings with Quality Improvement and Patient Safety (QIPS) and Training and Education identified as priority research areas.

Discussion

This study highlights the necessity of developing support systems and incorporating research priorities in QIPS, as well as Training and Education. The findings of this study align with the recommended core competencies and components for effective infection prevention and control programs, making them relevant to QIPS initiatives. The outcomes of the study will serve as a valuable resource to guide the IPS Research and Development Committee in delivering practical support to IPS members.

Analysing responsible innovation along a value chain-A single-cell protein case study

The British Standards Institution's Publicly Available Specification 440 (PAS 440) provides a Responsible Innovation Framework (RIF) that companies can use to continuously monitor the societal, environmental and health benefits and risks of their innovations, as well as relevant changes to the supply chain and regulations. PAS 440 is intended to help companies achieve the benefits of innovation in a timely manner and avoid any potential harm or unintended misuse of a new product, process or service. Here, the authors have applied the PAS 440 RIF to a novel single-cell protein (SCP) animal feed ingredient taking into consideration the perspectives of the value chain partners (VCPs), companies and laboratories involved in an Innovate UK research project. The authors' findings show how VCPs can use PAS440 to demonstrate that they are innovating responsibly. Using this approach to responsible innovation along the value chain-from manufacturing scale-up, through regulatory approval, to incorporation in animal feed and from there to food on supermarket shelves-can support the development of innovations that contribute to the economic and environmental sustainability of the animal feed sector. The authors conclude that the PAS 440 Guide can facilitate the progress of a new product throughout a value chain and contribute to coordinating responsible behaviour among companies involved in the value chain.

Research Note: Comparative effects of liquid and dry applications of a combination of lysolecithin, synthetic emulsifier, and monoglycerides on growth performance, nutrient digestibility, and litter moisture in broilers fed diets of differing energy density

Supplementation of a combination of lysolecithin, a synthetic emulsifier, and monoglycerides (LEX) in liquid and dry form to broiler diets with different energy levels was investigated to determine their effect on performance, litter quality and subsequent occurrence of footpad lesions. One thousand two hundred and forty-eight-day-old Ross 308 broilers were assigned to 1 of 6 treatments for a 42-day study: a basal diet with a normal energy content (NE); NE + 300 g/t LEX in liquid form (LEL); NE + 500 g/t LEX in dry form (LED); a basal diet with low energy (LE, -90 kcal/kg starter, -100 kcal/kg grower, finisher), LE + 300 g/t LEL and a LE + 500 g/t LED. Each treatment consisted of 13 pens of 16 birds each. Diets were fed in 3 phases (starter d 0-10, grower d 11-21, finisher d 22-42). Feed intake and weight were measured on d 0, 10, 21, and 42. On d 42 a litter sample was collected from each pen and 2 birds per pen were assessed for footpad lesions and breast scald. Data were analyzed using JMP 16, with means separation achieved using Tukey's HSD; significance was assumed at P < 0.05. Results showed a higher (P < 0.05) cumulative bodyweight gain with LEX supplementation (NE CON = 2,718 g, NE+LED = 2,829, NE+LEL = 2,895, LE CON = 2,722, LE+LED = 2,787, LE+LEL = 2,893; P = 0.0027). An increased feed intake was observed for the LE diets, however cumulative FCR of LE+LED and LE+LEL remained equal to the NE control (1.657 NE CON, 1.657 LE+LED, 1.623 LE+LEL; P > 0.05), suggesting LEX enabled the birds to compensate for the energy gap. Litter dry matter was significantly improved with both LED and LEL supplementation compared to the control groups, and resulted in lower (P < 0.05) occurrence and severity of footpad lesions and breast scalds. Considering the income over feed cost (IOFC) of the NE treatment as the reference point for comparison, all other treatments improved profitability, with NE+LEL and LE+LEL achieving the greatest IOFC with 154.58 and 175.96 €/1,000 birds respectively. In conclusion, feeding broilers a combination of lysophospholipids, a synthetic emulsifier and monoglycerides resulted in improved bird performance. The use of the LEX also improved litter quality and footpad health, therefore improving animal welfare indicators such as breast scald and footpad measurements.

Efficacy of oat hulls varying in particle size in mitigating performance deterioration in broilers fed low-density crude protein diets

Dietary fibres with increased particle size may develop foregut more efficiently in meat poultry fed diets moderately low in crude protein. The study investigated the performance of broilers fed low-density crude protein diets with the inclusion of oat hulls increasing in particle size. Ross 308 male broiler chicks (n = 336) were divided into 48 pens, 12 pens per treatment (7 chicks per pen). Pens were allocated to 4 dietary treatments in mash form; positive control (PC), a standard crude protein diet, negative control (NC), around 5% lower in protein with 5% celite as an inert material, OH400: 5% lower protein diet with 5% oat hulls of geometric mean diameter (GMD) 400 µm, OH850: 5% lower protein diet with 5% oat hulls of GMD 850µm. Birds were fed ad libitum from d 1 to 35 in 3 phases; starter: d 0 to 10, grower: d 10 to 24 and finisher: d 24 to 35. Growth performance was calculated at the end of the trial. Two birds per pen were sampled on d 24 and 35 to collect data on proventriculus and gizzard weights and pooled ileal digesta. Apparent ileal digestibility of amino acids on d 24, and metabolizable energy on d 24 and 35 were recorded for each pen. Litter was sampled from each pen on d 34 to analyze litter N and moisture content. Footpad dermatitis scores of all birds per pen were recorded on d 35. Overall, no difference (P > 0.05) in body weight gain and feed intake was found between the treatments. However, NC and OH400 showed poorer FCR than PC, whereas FCR on PC and OH850 was similar (P > 0.05). Gizzard absolute weight and relative to body weight, and gizzard to proventriculus ratio were higher (P < 0.05) on OH850 compared to PC and NC on d 24 and 35. Gizzard digesta particle size was reduced (P < 0.05) on OH850 compared to all other diets on d 24 and 35. Amino acids digestibility coefficients for aspartic acid and valine increased (P < 0.05) in birds fed OH850 compared to PC, whereas coefficients for several other amino acids were improved compared to NC and OH400. The apparent ileal digestibility of metabolizable energy was similar (P > 0.05) between PC and OH850. Litter moisture and nitrogen, and footpad dermatitis scores were reduced (P < 0.05) on OH850 compared to PC. In conclusion, the inclusion of coarse oat hulls of GMD 850 µm in low-density crude protein diets can be beneficial for the broilers in developing the foregut, utilizing the nutrients efficiently and reducing litter nitrogen and moisture, and footpad scores.

Spineless cactus cladode is a viable replacement to barley and maize grains in the feed rations of dromedary camel calves

BACKGROUND

No studies determined the use of spineless cactus cladodes in camel diets.

OBJECTIVES

The effect of replacing the main energy source in camel diets with fresh spineless cactus cladodes on growth performance was determined. Furthermore, the ability of morphology to predict cladodes yield was determined.

METHODS

A prediction model of spineless cactus cladode weight based on cladode volume was developed. Three cladodes per plants were randomly selected from 100 plants. Weight and volume were then recorded for each cladode. Sixteen male camel calves (196 ± 18.2 kg live weight and 430 ± 5.55 days of age) were allotted to treatments, control (conventional camel fattening diet based on cotton seed hulls, cereal grains and agro-industrial by-products) or cactus (barley and maize grains in the control diet were replaced totally by fresh cactus cladode on dry matter basis). The study contained a 100-days growth trial and a 21-day digestibility trial (15 days of adaptation and 7 days of faeces collection). Blood samples were collected monthly from each animal.

RESULTS

Cactus cladode volume predicted the dry weight with a high accuracy (prediction error = 3.5%). Nutrient intake and nutrient digestibility did not significantly differ among the dietary treatments (p > 0.05). The treatment significantly decreased feed conversion ratio by 1.52 points (p < 0.05). All blood parameters were within the normal range of dromedary camels.

CONCLUSIONS

Spineless cactus cladode is a potential replacement to the conventional energy sources in dromedary camel diets.

Effects of genotype and environment on forage yield, nutritive value and morphology of lablab (Lablab purpureus (L.) sweet)

The goal of the study is to determine the effect of genotype and environment on forage yield, forage nutritive value and to determine the relation between morphology and forage yield and nutritive value of lablab. Thirteen genotypes (one local and 12 improved) were replicated 3 times in a randomized complete block trial across three locations in Ethiopian lowlands namely, Bechi, Kite and Tepi. All forage samples were analyzed for dry matter (DM), crude protein (CP), and in vitro dry matter digestibility (IVDMD) using a combination of conventional nutritional analyses and near infrared reflectance spectroscopy. There was a significant (P < 0.001) effect of genotype, location and genotype*location on forage yield of DM, forage yield of CP, forage yield of IVDMD, CP, and IVDMD. The difference between means of minimum and maximum genotypes was 12.9 t/ha of DM, 3.12 t/ha CP, 8.22 t/ha IVDMD, 57 g/kg of CP and 56 g/kg of IVDMD. The correlation between plant morphology and forage yield and nutritive value was weak (r ≤ 0.41) in all locations and the combined data. Both genotype and location should be considered by the farmers when they decide to grow lablab for forage production. Morphological traits of lablab are not suitable to evaluate forage yield and nutritive value. Enhancing the awareness of farmers about the effect genetic-environment interaction effect of forage yield and nutritive value and the relation between morphology and yield and nutritive value would improve the uptake of lablab in mixed the farming system leading to more sustainable agricultural production.

Effect of rosemary (Rosmarinus officinalis) leaf meal supplementation on production performance and egg quality of laying hens

This experiment was conducted to investigate the supplemental effect of rosemary leaf meal (RLM) on egg production and egg quality in Lohmann-Brown laying hens. For each treatment, six replicates were performed with four 24-week-old laying hens for a total of 96 chickens. Dried rosemary leaf meal (RLM) was present in the commercial laying hen ration at 0, 1.7, 3.5 and 5.2%, respectively. The interactions between dietary treatments, egg storage temperatures (4 °C, 21.5 °C), and egg storage durations (7, 14, 21, 28, and 35 days) were examined in factorial designs using a fully randomized design. The data were analyzed using the Statistical Analysis System (SAS, 2014, Ver. 9.3) and Tukey's multiple range tests to separate the means. The inclusion of dried RLM at a level of 5.2% (p < 0.05) significantly improved the hens' daily egg production (78.9%). Feed conversion ratio (2.25) and egg weight (56.7 g) compared to control treatment. Similarly, at 3.5% and 5.2% RLM supplementation, eggshell weight (5.876 g) and eggshell strength increased significantly (p < 0.05) (compared to control, a weight of 3.76 kg/cm2 and a shell thickness (0.37 mm) was observed. In addition, the groups fed 5.2% RLM had significantly higher albumin weight (34.9 g/L), albumin height (6.9 mm), and yolk weight (15.6 g/L). l), yolk height (15.9 mm), yolk color (5.3 points), and Hough unit (83.9 points) than the control groups. Regarding the external characteristics of stored eggs, a group of hens fed at rates of 3.5 and 5.2% RLM showed significantly greater (p < 0.05) egg weight with increases in storage temperature and duration as a control group. There was a significant interaction effect between stored eggs collected from the supplemented groups in terms of egg weight, weight loss, shell weight, shell strength, and shell thickness stored at specific temperatures and storage durations. There was a decrease in albumen level and Haugh unit (HU) with an increase in storage temperature and duration over treatment (P < 0.05). Therefore, better external quality was observed in eggs collected from a group of chickens fed 4.5 and 5.2% RLM after 35 days of storage compared to a control group. Mean albumen height, albumen weight, HU, yolk height, and yolk color of eggs stored in the refrigerator (4 °C) were an exception for yolk weight, which was higher compared to room temperature (21.5 °C). Significantly low (P < 0.05) albumen height (6.61 to 2.96 cm), Hough unit (82.49 to 47.64 points), and yolk height (14.66 to 12.35 mm) were observed at 35 days storage recorded in the control group. In conclusion, supplementation with RLM at 3.5% and 5.2% improved the performance and quality of both fresh and stored eggs.

Accentuating the positive and eliminating the negative: Efficacy of TiO2 as digestibility index marker for poultry nutrition studies

Inert digestibility index markers such as titanium dioxide are universally accepted to provide simple measurement of digestive tract retention and relative digestibility in poultry feeding trials. Their use underpins industry practice: specifically dosing regimens for adjunct enzymes added to animal feed. Among these, phytases, enzymes that degrade dietary phytate, inositol hexakisphosphate, represent a billion-dollar sector in an industry that raises ca. 70 billion chickens/annum. Unbeknown to the feed enzyme sector, is the growth in cell biology of use of titanium dioxide for enrichment of inositol phosphates from extracts of cells and tissues. The adoption of titanium dioxide in cell biology arises from its affinity under acid conditions for phosphates, suggesting that in feeding trial contexts that target phytate degradation this marker may not be as inert as assumed. We show that feed grade titanium dioxide enriches a mixed population of higher and lower inositol phosphates from acid solutions. Additionally, we compared the extractable inositol phosphates in gizzard and ileal digesta of 21day old male Ross 308 broilers fed three phytase doses (0, 500 and 6000 FTU/kg feed) and one inositol dose (2g/kg feed). This experiment was performed with or without titanium dioxide added as a digestibility index marker at a level of 0.5%, with all diets fed for 21 days. Analysis yielded no significant difference in effect of phytase inclusion in the presence or absence of titanium dioxide. Thus, despite the utility of titanium dioxide for recovery of inositol phosphates from biological samples, it seems that its use as an inert marker in digestibility trials is justified-as its inclusion in mash diets does not interfere with the recovery of inositol phosphates from digesta samples.

Can the broiler industry rely on results of existing life cycle assessment and environmental assessments studies to inform broilers' nutritional strategies?

The goal of this systematic review is to investigate the applicability of the results from existing life cycle analysis (LCA) and environmental assessments studies in informing nutritional strategies for environmentally sustainable poultry meat production. This paper reports on a Rapid Evidence Assessment (REA) of articles published between 2000 and 2020. The studies reviewed were conducted in developed countries including UK, France, Germany, Sweden, Norway, The Netherlands, Denmark, Belgium, Canada, and USA. All articles were written in English. The REA includes studies on LCA of differing strains of meat poultry and production systems, studies on poultry manure emission and studies on environmental assessments of plant-based feed ingredients. The review covered studies on soil carbon dynamics associated with plant-based ingredients. Web of Science, Scopus, and PubMed were used to obtain the 6,142 population articles. The multistage screening process resulted in 29 studies from which 15 studies included LCA while the rest 14 studies analyzed NH₃ emission of broilers. All studies based on LCA were descriptive and did not include replications. Only 12 studies assessed the effect of interventions to reduce NH₃ emission of broiler litter using replicated layout designs. It is concluded that the broiler industry in UK, EU, and North America cannot rely on results of existing LCA and environmental assessments studies to inform their nutritional strategy and poultry meat production due to a shortage of reliable in vivo data assessing interventions in controlled studies.

Adverse childhood experiences and sleep links in a predominantly Black sample of overweight adults

Adverse childhood experiences (ACEs) have been associated with worse sleep, but existing literature is limited by use of predominantly White samples, lack of objective sleep measurement, and use of non-standardized questionnaires. We investigated associations between retrospectively reported ACEs and sleep in adulthood in a sample of 43 adults 20-53 years of age, free from chronic conditions, with a Body mass index (BMI) ≥ 25 (Mean age = 33.14 [SD = 10.05], 74% female, 54% Black). Sleep efficiency (SE), total sleep time (TST), wake after sleep onset (WASO), and sleep onset latency (SOL), were measured by actigraphy and daily diary. Global sleep quality and insomnia severity were measured by questionnaires. Sleepiness, fatigue, and sleep quality were also measured by daily diary. Adjusting for demographic characteristics and BMI, ACEs were significantly associated with poorer global sleep quality and diary measures of greater daytime sleepiness, fatigue, and poorer sleep quality. There were no significant associations between ACEs and SE, TST, WASO, or SOL measured by diary or actigraphy. Findings suggest that ACEs are associated with worse sleep perception and daytime functioning in adulthood. Larger prospective studies are needed to replicate these findings, examine racial/ethnic differences, and determine temporal associations between ACEs, sleep, and health (e.g., BMI).

Preliminary Evidence for the Sequentially Mediated Effect of Racism-Related Stress on Pain Sensitivity Through Sleep Disturbance and Corticolimbic Opioid Receptor Function

Sleep disturbance predicts worse pain outcomes. Because sleep disturbance inequitably impacts Black adults - with racism as the upstream cause - understanding how racism-related stress impacts pain through sleep might help minimize racialized pain inequities. This preliminary study examined sequential mediation of the effect of racism-related stress on experimental pain through sleep disturbance and corticolimbic μOR function in pain-free non-Hispanic Black (NHB) and White (NHW) adults. Participants completed questionnaires, actigraphy, positron emission tomography, and sensory testing. We reproduced findings showing greater sleep disturbance and pain sensitivity among NHB participants; greater sleep disturbance (r = .35) and lower pain tolerance (r=-.37) were significantly associated with greater racism-related stress. In a sequential mediation model, the total effect of racism-related stress on pain tolerance (β=-.38, P = .005) weakened after adding sleep disturbance and ventromedial prefrontal cortex (vmPFC) μOR binding potential (BPND) as mediators (β = -.18, P = .16). The indirect effect was statistically significant [point estimate = -.003, (-.007, -.0003). Findings showed a potential sequentially mediated effect of racism-related stress on pain sensitivity through sleep disturbance and vmPFC μOR BPND. As policy efforts are enacted to eliminate the upstream cause of systemic racism, these results cautiously suggest that sleep interventions within racism-based trauma informed therapy might help prevent downstream effects on pain. PERSPECTIVE: This preliminary study identified the effect of racism-related stress on pain through sleep disturbance and mu-opioid receptor binding potential in the ventromedial prefrontal cortex. Findings cautiously support the application of sleep interventions within racism-based trauma-informed therapy to prevent pain inequities as policy changes function to eliminate all levels of racism.

Phytase dose-dependent response of kidney inositol phosphate levels in poultry

Phytases, enzymes that degrade phytate present in feedstuffs, are widely added to the diets of monogastric animals. Many studies have correlated phytase addition with improved animal productivity and a subset of these have sought to correlate animal performance with phytase-mediated generation of inositol phosphates in different parts of the gastro-intestinal tract or with release of inositol or of phosphate, the absorbable products of phytate degradation. Remarkably, the effect of dietary phytase on tissue inositol phosphates has not been studied. The objective of this study was to determine effect of phytase supplementation on liver and kidney myo-inositol and myo-inositol phosphates in broiler chickens. For this, methods were developed to measure inositol phosphates in chicken tissues. The study comprised wheat/soy-based diets containing one of three levels of phytase (0, 500 and 6,000 FTU/kg of modified E. coli 6-phytase). Diets were provided to broilers for 21 D and on day 21 digesta were collected from the gizzard and ileum. Liver and kidney tissue were harvested. Myo-inositol and inositol phosphates were measured in diet, digesta, liver and kidney. Gizzard and ileal content inositol was increased progressively, and total inositol phosphates reduced progressively, by phytase supplementation. The predominant higher inositol phosphates detected in tissues, D-and/or L-Ins(3,4,5,6)P4 and Ins(1,3,4,5,6)P5, differed from those (D-and/or L-Ins(1,2,3,4)P4, D-and/or L-Ins(1,2,5,6)P4, Ins(1,2,3,4,6)P5, D-and/or L-Ins(1,2,3,4,5)P5 and D-and/or L-Ins(1,2,4,5,6)P5) generated from phytate (InsP6) degradation by E. coli 6-phytase or endogenous feed phytase, suggesting tissue inositol phosphates are not the result of direct absorption. Kidney inositol phosphates were reduced progressively by phytase supplementation. These data suggest that tissue inositol phosphate concentrations can be influenced by dietary phytase inclusion rate and that such effects are tissue specific, though the consequences for physiology of such changes have yet to be elucidated.

Prevention of Exposure Keratopathy in the Intensive Care Unit: Evaluation of an EMR-Based Lubrication Order Protocol for Ventilated Patients

Purpose In this pilot study, we aimed to investigate the efficacy of an electronic medical record (EMR) order set for lubricating ointment (four times daily) in the prevention of exposure keratopathy in ventilated patients in the intensive care unit (ICU) at the University of Utah. We attempted to capture the magnitude of morbidity, cost, and care burden in ventilated patients, as well as the utility of a systematic EMR-based preventative lubrication protocol in the ICU setting.

Methods After implementation of the order set, a retrospective chart review was performed to capture all ventilated ICU patients pre- and postintervention. Three separate study periods were used: (1) Six months prior to coronavirus disease 2019 (COVID-19) and prior to the ocular lubrication intervention; (2) the subsequent 6-month period including COVID-19 patients but prior to any intervention; and (3) the subsequent 6-month period postintervention, including COVID-19 patients. The primary endpoint of ointment use per day was analyzed with a Poisson regression model. Secondary endpoints including rates of ophthalmologic consultation and exposure keratopathy were compared with Fisher's exact test. A poststudy survey of ICU nurses was included.

Results A total of 974 ventilated patients were included in the analysis. Ointment use per day increased by 155% (95% confidence interval [CI] 132–183%, p < 0.001) following the intervention. Rates also increased 80% (95% CI 63–99%, p < 0.001) during the COVID-19 study period but prior to intervention. The percentage of ventilated patients requiring a dilated eye exam for any indication was 3.2, 4, and 3.7% in each of the study periods, respectively. There was an overall down trend in the rate of exposure keratopathy which was diagnosed in 33.3, 20, and 8.3% of those receiving ophthalmologic consultation, though these rates were not statistically significant.

Conclusion These preliminary data show a statistically significant increase in the rates of lubrication in mechanically ventilated patients using an EMR-based order set in the ICU setting. There was no statistically significant decrease in the rates of exposure keratopathy. Our preventative protocol with lubrication ointment was of minimal cost burden to the ICU. Further longitudinal and multicenter studies are needed to better assess the efficacy of such a protocol.

The protected antimicrobial process in a University Teaching Hospital: a qualitative interview study exploring the knowledge, attitudes, and experiences of healthcare professionals

Background The protected or restricted supply of certain antimicrobials such as linezolid, caspofungin, aztreonam, in the acute hospital setting is an important element of Antimicrobial Stewardship (AMS) programmes to address the growing problem of antimicrobial resistance. This process involves submitting an application for use to be reviewed typically by a Consultant Microbiologist, Infectious Disease Consultant or Antimicrobial Pharmacist. Aim To investigate healthcare professionals’ knowledge, experiences, and attitudes towards the protected/restricted antimicrobials process in order to identify possible methods of optimisation and improvement. Method Semi-structured interviews with stakeholders involved in the protected/restricted antimicrobial prescribing, dispensing and administration process were conducted in September–October 2019 in a 350-bed voluntary, general, acute hospital in Ireland. Interviews were analysed by the Framework method and mapped to the Theoretical Domains Framework (TDF). Results Interviews were conducted with 8 Doctors, 4 Pharmacists and 3 Nurses. TDF domains identified included: ‘Knowledge’; ‘Social/professional role and identity’; ‘Social influences’; ‘Memory, attention and decision processes’; ‘Beliefs about consequences’; ‘Environmental contexts and resources’. The relationship between prescribers and the AMS Team was reported as a facilitator of the process, whereas the inconsistency of the filing and versions of forms on the wards were seen as challenges. Conclusion The results of this study have shown that the existing protected/restricted antimicrobial process is a multi-disciplinary effort with barriers that require attention in order to make future improvements. Standardization of the form across all wards, an electronic version of the form, and structured education around AMS were suggested to optimize the process.

255 A QUALITATIVE STUDY OF OLDER ADULTS’ EXPERIENCES OF EMBEDDING PHYSICAL ACTIVITY WITHIN THEIR HOME CARE SERVICES

Background

Physical activity programmes have been shown to improve older adults’ functional capacity, independence and quality of life. Research around structured exercise programmes has been completed in different groups of community-dwelling older people, however few studies have focused on the older population receiving formal home care. In a feasibility study, we embedded physical activity within older adults existing home care services through the ‘Care to Move’ (CTM) programme. The aim of this qualitative study is to explore older adults’ experiences of the CTM programme.

Methods

We conducted semi-structured telephone interviews with 13 older adults and one carer. Topics covered included participants overall experiences of the CTM programme, changes to their overall activity and participation, aspects of the programme that they liked or found valuable and issues that they found challenging. Interview transcripts were coded and analysed thematically to capture barriers and facilitators to programme delivery.

Results

Four themes emerged: i) ‘I’m feeling good about it’, ii) ‘safety and security is the name of the game’, iii) ‘we’re a team as it stands’, iv) ‘it’s [COVID] depressing for everybody at the moment’. Older adults identified benefits of CTM participation including improvements in physical and psychological wellbeing. However, frailty and multimorbidity influenced overall engagement. Participants expressed concerns around the logistics of programme delivery and competing healthcare assistant (HCA) interests. The broader role of HCA’s in supporting the CTM programme was highlighted as well as the emotional support that HCAs provided to older adults. HCA continuity was identified as a barrier to ongoing programme engagement. The impact of COVID on older adults physical and mental health negatively impacted programme delivery.

Conclusion

Our findings suggest that embedding the CTM programme within home support services is feasible. Restructuring of services, addressing HCA continuity, and adopting individual approaches to programme delivery may enhance the implementation of services.

199 EMBEDDING PHYSICAL ACTIVITY WITHIN HOME CARE SERVICES FOR OLDER ADULTS IN IRELAND—A QUALITATIVE STUDY OF BARRIERS AND FACILITATORS

Background

In Ireland, over 53,000 older adults are supported in their community by formal home support, amounting to an estimated 19 million care hours annually. There is a growing need to move beyond care, to more proactive approaches to maintain physical function. In a feasibility study, we delivered the ‘Care to Move’ (CTM) programme through existing home support services. The aim of the present qualitative study was to explore the experience and perceptions of Health Care Assistants (HCAs), who were trained in, and delivered the CTM programme.

Methods

We conducted semi-structured telephone interviews with 22 HCAs involved in the delivery of the programme among older adults [n = 35, mean age 82.8 (7.8) years]. Interview transcripts were coded and analysed thematically to capture barriers and facilitators to programme delivery.

Results

Barriers and facilitators were identified under three main themes i) the programme ii) the care setting, iii) the clients. Overall, there was a positive perception of the programme’s focus on ‘movement prompts and motivators’, the ‘fit’ within home support services, and the training provided. Practical challenges of limited time and the task-orientation nature of home support were reported as recurring barriers for CTM. Many HCAs commented on the value and perceived positive benefits of the programme for their clients. Though negative perceptions of older adult’s motivation or ability to engage with physical activity also emerged. Risk, such as injury or pain, was identified but was not a dominant theme.

Conclusion

Our preliminary findings suggest that embedding physical activity initiatives within home support services could be feasible. Restructuring of services, engaging HCAs, and moving beyond traditional ‘task-oriented' care models to more personalised proactive approaches may facilitate this initiative and support ageing in place.

Evaluation of dried papaya pomace meal in laying hen diets

In the search for alternative feed resources for laying hens, papaya pomace is available as industrial by-product but information on its nutritive value is lacking. Dried papaya pomace was included in a common laying hen diet at 0%, 2.5%, 5% and 7.5% to evaluate its effect on egg production performance, egg quality and general health parameters in Bovan brown layers. For every inclusion level, three cages with ten 20-week-old layers were used, making a total of 120 hens. The effect of dried papaya pomace inclusion on egg production, egg quality and general health parameters was evaluated. Dried papaya pomace inclusion improved egg production and laying by 6.15% and 17% respectively, while it significantly decreased feed conversion ratio by 7.5%. Eggshell weight, thickness and strength of PP5 were higher than the control by 0.3 g, 0.8 mm and 0.43 kg/cm² , respectively. There was a significant improvement in albumin weight (by 1.5 g/L), albumin height (2.1 mm), yolk weight (0.4 g/L), yolk height (0.4 mm), yolk colour (4.4 points) and Haugh unit (8 points) due to PP5 treatment. Inclusion of papaya pomace at a level of 7.5% of layers diet had negative effect on Egg production, feed conversion ratio and interior and exterior egg quality traits. Inclusion of papaya pomace affected significantly serum total cholesterol, serum triglyceride, serum low density lipoprotein, serum high density lipoprotein, aspartate aminotransferase, alanine aminotransferase and white blood cell count. However, all blood traits of the experimental animals were within the normal ranges reported for layers. Inclusion of papaya pomace in 5% of layers commercial diets improves egg production and quality without negative impact on health while decreasing feeding cost.

Effect of olive tree leaves and twigs on intake, digestibility, growth performance and blood variables of Shami goats

The effect of replacing wheat straw and a portion of commercial concentrate with olive twigs and leaves treated with urea and molasses on nutrient digestibility, growth performance and blood variables was determined. Forty‐two Shami goat kids (20 ± 2.47 kg live weight and 133 ± 5.44 days of age) were randomly allotted to three dietary treatment groups, control (75% commercial concentrate and 25% wheat straw), OTU (62.3% commercial concentrate + 37.7% olive twigs and leaves treated with 4% urea for 14 days), OTUM (51.5% concentrate mixture + 48.5% olive twigs and leaves treated with 4% urea for 14 days then sprayed by 10% molasses). Cost (SYP/t) of control, OUT and OTUM was 12,600, 10,066 and 10,106 respectively. The study consisted of a growth trial of 100 days and a digestibility trial of 12 days (7 days of adaptation and 5 days of urine and faeces collection). Serum urea, total protein, albumin, alanine aminotransferase activity, aspartate aminotransferase activity, glucose, cholesterol, creatinine, haemoglobin and packed cell volume were determined. Daily dry matter intake, digestibility of crude protein, ether extract and nutrient detergent fibre did not significantly differ among the dietary treatments (p > .05). Nitrogen intake, nitrogen excretion in urine and faeces and nitrogen balance was not significantly affected (p > .05) by the dietary treatment. The dietary treatment did not have any significant effect on average daily gain, feed conversion ratio or blood variables (p > .05). Olive twigs treated with 4% urea and OTUM replaced 37.7% and 48.5% of conventional diets of growing Shami goat kids without negative effects on growth performance nor health and potentially reduced fattening costs for farmers in olive‐livestock mixed systems by 19.8 and 20%, respectively. OUT is technically simpler than OTUM, thus, it could replace the conventional fattening ration of Shami male goat.

Shami goat were fed on Olive twigs treated with 4% urea and 10% Olive twigs treateb with 4% urea replaced 48.5% of the ration without negative effect on growth performance This replacement did not affect goat health but decreased feeding cost by 20%.

EPID-11. A MULTI-INSTITUTIONAL COMPARATIVE ANALYSIS OF THE CLINICAL, GENOMIC, AND SURVIVAL CHARACTERISTICS OF PEDIATRIC, YOUNG ADULT AND OLDER ADULT PATIENTS WITH IDH-MUTANT GLIOMA

BACKGROUND

Prognostic significance of IDH-mutation in glioma is incompletely understood in children and adolescents/young adults (YAs). We compared the clinico-genomic features, outcomes and prognostic factors observed in IDH-mutant gliomas across age groups.

METHODS

Clinical, histologic and molecular data of patients with IDH-mutant gliomas from 8 pediatric institutions (spanning twenty years) and adult patients from two institutions (from 2013–2019) were identified. Patients were grouped as pediatric (&lt; 19y), YA (19y to &lt; 40y) or older adult (≥ 40y). Genomic alterations, including somatic mutations and copy number variants, were captured with institutional next generation sequencing. Factors were compared across age categories using Fisher’s exact test or analysis-of-variance. Cox proportional-hazards regression tested factors for association with overall (OS) and progression-free survival (PFS).

RESULTS

Of 379 patients, 48(13%) were pediatric, 204(54%) YA and 127(33%) older adult. Histological subtype differed significantly by age group (p&lt; 0.0001). YAs had higher rates of malignant transformation (p=0.01) and shorter time-from-diagnosis-to-malignant transformation (p=0.01) compared to other age groups. Analysis of genomic alterations revealed an age-related difference in distribution in ATRX mutations only (p=0.0018). Median PFS and OS for the entire cohort were 4.62 and 17.19 years. In univariate models, PFS differed by age group (p=0.0012), with YAs having the worst outcomes. Lack of MGMT methylation (p=0.024) predicted poorer OS. Upfront observant management was predictive of poorer PFS. Gene mutations were not associated with PFS. In multi-variable models, YAs had shorter PFS compared to pediatric (hazard ratio [HR]=2.03, p=0.01) and older adults (HR=1.59, p=0.003) after adjusting for histology, extent of resection, and initial therapy. Age at diagnosis was not associated with OS in multi-variable analysis.

CONCLUSIONS

Within our cohort, YA with IDH-mutant tumors progressed more quickly compared to their pediatric counterparts. Further study of YA patients with IDH-mutant glioma is critical to better define best practices for this group.

The role of gonadotrophins in gonocyte transformation during minipuberty

PURPOSE

Postnatal surge of gonadotrophins, Luteinizing hormone (LH) and Follicle-Stimulating hormone (FSH) known as minipuberty, is critical for gonocyte maturation into spermatogonial stem cells (SSC) in the testis. Gonadotrophins are essential for optimum fertility in men, but very little is known how they regulate germ cells during minipuberty. This study examined whether gonadotrophins play a role on gonocyte transformation in vivo.

METHODS

Testes from hypogonadal (hpg) mice and their wild type (WT) littermates (n = 6/group) were weighed, and processed in paraffin at postnatal days (D) 0, 3, 6 and 9. Mouse VASA homologue (germ cell marker), anti-Müllerian hormone (Sertoli cell marker) antibodies and DAPI (nuclei marker) were used for immunofluorescence followed by confocal imaging. Germ cells on or off basement membrane (BM) and Sertoli cells/tubule were counted using Image J and analyzed with GraphPad.

RESULTS

Comparing to WT littermates, there were significantly fewer germ cells on BM/tubule (p < 0.05) in D9 hpg mice, whereas there was no significant difference for germ cells off BM/tubule and Sertoli cells/tubule between littermates. However, testicular weight was significantly reduced in D3-D9 hpg mice comparing to WT littermates.

CONCLUSION

Gonadotrophin deficiency reduced D9 germ cells on BM indicating impaired gonocyte transformation into SSC. This suggests that gonadotrophins may mediate gonocyte transformation during minipuberty.

G-Protein coupled receptors: structure and function in drug discovery

The G-protein coupled receptors (GPCRs) superfamily comprise similar proteins arranged into families or classes thus making it one of the largest in the mammalian genome. GPCRs take part in many vital physiological functions making them targets for numerous novel drugs. GPCRs share some distinctive features, such as the seven transmembrane domains, they also differ in the number of conserved residues in their transmembrane domain. Here we provide an introductory and accessible review detailing the computational advances in GPCR pharmacology and drug discovery. An overview is provided on family A-C GPCRs; their structural differences, GPCR signalling, allosteric binding and cooperativity. The dielectric constant (relative permittivity) of proteins is also discussed in the context of site-specific environmental effects.

Does the apoptosis pathway play a critical role in gonocyte transformation?

PURPOSE

Undescended Testes (UDT) are prevalent in 2%-5% of male infants and cause malignancy and infertility. During germ cell development, abnormal gonocytes usually undergo apoptosis. This process is believed to involve BAX (Bcl-2 Associated X) protein in clearing abnormal gonocytes which may fail in UDT, resulting in persisting gonocytes causing seminomas later in life. We aim to investigate the role of BAX in gonocyte apoptosis.

MATERIALS AND METHODS

BAXKO (BAX-knockout) mice were back-crossed to OG2 mice (Oct4-promoter driving enhanced green fluorescent protein-eGFP) to produce BAXOG2 mice. Testes (wildtype-BAX^+/+, heterozygous-BAX^+/- and homozygous-BAX^-/- mice, n = 6/group) on postnatal days 1, 3, 6, 9 were fixed and embedded in OCT for frozen sectioning. Sections were labeled with Anti-Müllerian Hormone (Sertoli cell marker), Mouse Vasa Homolog (germ cell marker) and DAPI (nucleus marker) and imaged using confocal microscopy. Oct4-GFP+ve germ cells, germ cells on/off the basement membrane and Sertoli cells were counted using ImageJ followed by data analysis with GraphPad.

RESULTS

BAX^-/-OG2 mice had significantly higher number of germ cells/tubule comparing to BAX^+/+OG2 on day 9. There were Oct4-GFP+ve gonocyte-like germ cells that persisted in the center of the tubules in BAX^-/-OG2 even after the completion of gonocyte transformation. This suggests that abnormal gonocytes in BAX^-/-OG2 mice failed to undergo apoptosis and are allowed to persist.

CONCLUSION

This study demonstrated that apoptosis is important in regulating germ cell migration and differentiation during gonocyte transformation in neonatal mice. In addition, inhibition of apoptosis results in persisting neonatal gonocytes which might become seminomas in patients with UDT.

Lysolecithin, but not lecithin, improves nutrient digestibility and growth rates in young broilers

1. The potential of lecithin and lysolecithin to improve lipid digestion and growth performance was investigated in three experiments: 1. an in vitro model that mimics the intestinal conditions of the chick, 2. a digestibility trial with chicks (5-7 days of age), and 3. a performance trial until 21 days of age. 2. In experiment 1, palm oil (PO), palm oil with lecithin (PO+L), and palm oil with lysolecithin (PO+LY) were subjected to in vitro hydrolysis and applied to Caco-2 monolayers to assess lipid absorption. 3. The in vitro hydrolysis rate of triglycerides was higher in PO+LY (k = 11.76 × 103/min) than in either PO (k = 9.73 × 103/min) or PO+L (k = 8.41 × 103/min), and the absorption of monoglycerides and free fatty acids was highest (P < 0.01) for PO+LY. In experiment 2, 90 broilers were assigned to three dietary treatments: a basal diet with 4% palm oil, and the basal diet supplemented with either 250 ppm lecithin or lysolecithin. 4. ATTD of crude fat was higher in broilers supplemented with lysolecithin, but was lower in broilers supplemented with lecithin. DM digestibility and AMEn in birds supplemented with lysolecithin were significantly higher (3.03% and 0.47 MJ/kg, respectively). 5. In experiment 3, 480 broilers were randomly allocated to four dietary treatments: basal diet with soybean oil (2%), basal diet with lecithin (2%), soybean oil diet with 250 ppm lysolecithin, or lecithin oil diet with 250 ppm lysolecithin. 6. Lecithin diets significantly reduced weight at day 10 and 21 compared with soybean oil. However, the addition of lysolecithin to lecithin-containing diets significantly improved bird performance. 7. The results of these studies showed that, in contrast to lecithin, lysolecithin was able to significantly improve the digestibility and energy values of feed in young broilers.

Characterization of yellow root cassava and food products: investigation of cyanide and β-carotene concentrations

Objective

Cyanide is a highly toxic compound, and the consumption of products containing cyanide is a significant public health concern. Conversely, β-carotene possesses essential nutritional attributes for human health, therefore the characterisation and quantification of both compounds in food products is fundamental. Herein, cyanide and β-carotene levels in two flours produced from the roots of two varieties of cassava (Manihot esculenta crantz), namely UMUCASS-38(TMS 01/1371) and NR-8082, and their associated food products were detected and quantified.

Results

The cyanide content of NR-8082 and UMUCASS-38 flours was determined at 18.01 ± 0.01 ppm and 17.02 ± 0.02 ppm (mean ± SD), respectively. These flours contained significantly higher (p < 0.05) than the residual cyanide levels determined in the cookies and cake produced therefrom with levels of 10.00 ± 0.00 ppm and 7.10 ± 0.14 ppm (mean ± SD), respectively. The levels of β-carotene determined in both the cake and cookie samples varied significantly (p < 0.05). The highest levels of β-carotene at 6.53 ± 0.02 µg/g (mean ± SD) were determined in raw roots of UMUCASS-38. While NR-8082 levels of β-carotene were less than UMUCASS-38 at 1.12 ± 0.02 µg/g (mean ± SD). Processing the roots into flour reduced the β-carotene content to 4.78 ± 0.01 µg/g and 0.76 ± 0.02 µg/g (mean ± SD) in UMUCASS-38 and NR-8082 flours, respectively. Cookies and cake produced from flour derived from the UMUCASS-38 variety had (mean ± SD) 2.15 ± 0.01 µg/g and 2.84 ± 0.04 µg/g of β-carotene, respectively.

Sensitivity of larval and juvenile freshwater mussels (unionidae) to ammonia, chloride, copper, potassium, and selected binary chemical mixtures

In aquatic environments, organisms such as freshwater mussels are likely exposed to complex contaminant mixtures related to industrial, agricultural, and urban activities. With growing interest in understanding the risk that chemical mixtures pose to mussels, this investigation focused on the effects of various waterborne contaminants (ammonia, chloride, copper, and potassium) and selected binary mixtures of these chemicals following a fixed-ratio design to Villosa iris glochidia and juvenile Lampsilis fasciola. In individual exposures, 48-h EC₅₀ values were determined for V. iris glochidia exposed to ammonia chloride (7.4 [95% confidence interval (CI) 6.6-8.2] mg N/L), ammonia sulfate (8.4 [7.6-9.1] mg N/L), copper sulfate (14.2 [12.9-15.4] μg Cu²⁺/L), potassium chloride (12.8 [11.9-13.7] mg K⁺/L), potassium sulfate (10.1 [8.9-11.2] mg K⁺/L), and sodium chloride (480.5 [435.5-525.5] mg Cl^-/L). The 7-d LC₅₀ values for juvenile L. fasciola were determined for potassium sulfate (45.0 [18.8-71.2] mg K⁺/L), and sodium chloride (1738.2 [1418.6-2057.8] mg Cl^-/L). In Ontario these waterborne contaminants have been reported to co-occur, with concentrations exceeding the EC₁₀ for both life stages at some locations. Data from binary mixture exposures for V. iris glochidia (chloride-ammonia, chloride-copper, and copper-ammonia) and juvenile L. fasciola (chloride-potassium) were analyzed using a regression-based, dose-response mixture analysis modeling framework. Results from the mixture analysis were used to determine if an additive model for mixture toxicity [concentration addition (CA) or independent action (IA)] best described the toxicity of each mixture and if deviation towards dose-ratio (DR) or dose-level (DL) synergism/antagonism (S/A) occurred. For all glochidia binary mixture exposures, CA was the best fit model with DL deviation reported for the chloride-copper mixture and DR deviation reported for the copper-ammonia mixture. Using the model deviation ratio (MDR), the observed toxicity in all three glochidia mixture exposures were adequately described by both CA (mean = 0.71) and IA (mean = 0.97) whereas the juvenile mixture exposure was only adequately described by CA (mean = 0.64; IA mean = 0.05).

Performance of broilers and layers supplemented with Moringa stenopetala leaf meal under hot humid tropical conditions

Context Heat stress poses a major limit to poultry production. Moringa stenopetala leaf meal (MSL) could be a promising feed additive for poultry raised under heat stress, as it is rich in antioxidants. Aims To determine the effect of (MSL) supplementation on the production and quality of broilers under heat-stress conditions. Methods In the broiler performance trial, 156 1-day old Cobb 500 broilers were assigned to four groups, with each containing three replicates of 13 chicks. For the egg production trial, 108 Bovan Brown layers aged 20 weeks were allocated to four groups, with each containing three replicates of nine hens. The four groups of broiler and layer chicken were supplemented with MSL at a level of 0% (control), 1% (MSL1), 1.5% (MSL1.5) and 2% (MSL2). Relative humidity, and minimum and maximum temperatures were 82%, 13°C and 23°C respectively. The effects of MSL supplementation on growth performance, characteristics of digestive organs, carcass traits, egg production and egg quality were analysed with one-way ANOVA. Key results Moringa stenopetala-leaf supplementation at a level up to 2% (MSL2) did not significantly affect feed intake, weight gain or feed conversion ratio of the birds. Supplemented broilers had a significantly longer large intestine (24% for MSL1, 37% for MSL1.5 and 49% for MSL2) and a heavier pancreas (82% for MSL1, 67% for MSL1.5, and 57% for MSL2) than did the control broilers. Hot and cold carcass weights, dressing yield, dressing percentage, breast-meat weight, drumstick and thigh-meat weights, wing-meat weight, back weight and meat pH were not significantly affected by MSL supplementation. Ash content of meat of the MSL2-fed birds was significantly higher than that of the control birds (3.51% vs 2.74% respectively). Egg production, feed conversion ratio and interior and exterior egg-quality parameters were not significantly affected by MSL supplementation. Intensity of yolk colour was significantly and linearly enhanced due to MSL supplementation (by ~5–8 times compared with the control). Conclusions Supplementation with MSL at a level up to 2% improved yolk colour of Bovan Brown layer eggs, with no effect on meat and egg production. Implications Yolk colour of eggs of layers raised under heat stress can be improved by MSL supplementation at 1%, with there being a minimum increase in the diet cost.

Spineless cactus (Opuntia ficus-indica) and saltbush (Atriplex halimus L.) as feed supplements for fattening Awassi male lambs: effect on digestibility, water consumption, blood metabolites, and growth performance

The effect of replacing 13.6% and 20.3% of a total ration of fattening Awassi lambs by two combinations of fresh saltbush (Atriplex halimus) and fresh spineless cactus (Opuntia ficus-indica) cladodes at a ratio of 1.9:1 (TRT1) and 1.7:1 (TRT2) on water intake, digestibility, blood metabolites, and fattening performance was evaluated. Thirty-six lambs with average initial live weight 34.5 ± 4.18 kg were randomly assigned to three diets (control, TRT1, and TRT2). The control received a diet containing 166 g/kg barley straw and 834 g/kg of commercial concentrate mixture; TRT1 comprised 126 g barley straw, 739 g/kg concentrate mixture, 47 g/kg spineless cactus, and 89 g saltbush; TRT2 comprised 67 g/kg barley straw, 704 g/kg commercial concentrate mixture, 86 g/kg spineless cactus, and 144 g saltbush. A growth trial of 100 days (10 days of adaptation and 90 days of collection) followed by a metabolism trial of 17 days (10 days of adaptation and 7 days of a total feces and urine collection) was carried out. Daily dry matter intake, digestibility of crude protein, ether extract and nutrient detergent fiber, nitrogen balance, average daily gain, feed conversion ratio, and blood metabolites were not significantly affected by the treatment. Water consumption in TRT2 was significantly 16% less compared with the control. A combination of saltbush and spineless cactus at a ratio of 1.7:1 (TRT2) replaced 60% of barley straw and 16% of concentrate mixture without adverse effects on health and growth performance of Awassi male lambs. This represents a potential reduction in feed costs for smallholder farmers.

Amino acid digestibility of larval meal (Musca domestica) for broiler chickens

Work was undertaken to investigate the potential use of housefly (Musca domestica) larvae reared on broiler manure as a source of nutrition for poultry production in the United Kingdom. Nutritional analysis showed that larvae have a high (>45% dry wt.) protein content and a favorable amino acid profile that is rich in key amino acids, such as lysine and methionine. A broiler digestibility trial was carried out to determine the apparent ileal digestibility coefficients (AIDC) and true ileal digestibility coefficients (TIDC) of amino acids (AA) from insect larval meal (ILM) from M. domestica and fishmeal (FM) in broiler chickens. This was calculated using multiple linear regression technique based upon 3 inclusions of each protein source in a semisynthetic diet. One-hundred-forty-four day-old male (Ross 308) broilers were fed from hatch on a commercial starter diet for 20 days. Experimental diets were fed from d 21 to 28, and feed intakes were measured daily. On d 28, the trial was terminated, ileal digesta were collected for the determination of AIDC and TIDC of AA, and inflammatory responses (gizzard erosion and eye discharge) were measured. No significant differences were observed in digestibilities between protein sources for any AA. Furthermore, ILM feeding did not induce gizzard erosion or eye discharge at any inclusion. These results provide strong evidence to suggest that ILM of the common housefly can provide a successful alternative protein source to FM in broiler diets.

Preliminary Studies on Bemitradine-Induced Cardiotoxicity in Female Rats

The mechanism of bemitradine (SC-33643) cardiotoxicity in female rats was investigated in the set of preliminary experiments reported here. Specifically, the involvement of bemitradine metabolites and the potential role of adrenal epinephrine release were examined. Desethylbemi-tradine (the primary metabolite of bemitradine) was shown to be cardiotoxic at oral dosages greater than 300 mg/kg for 7 days. In a separate experiment, a major metabolite (bemitradine glycol) unique to the rat was not cardiotoxic at dosages up to 600 mg/kg for 7 days. Treatment of rats with SKF 525-A enhanced the lethality and the cardiotoxicity of bemitradine. In contrast, prior treatments of rats with phenobarbital resulted in decreased cardiotoxicity of both bemitradine and desethylbemitradine (a bemitradine metabolite presumably further metabolized by the microsomal mixed function oxidases). In other independent experiments, bemitradine-induced cardiotoxicity was shown to be accompanied by adrenal damage and decreases in adrenal epinephrine. Propranolol (a β-antagonist) treatment protected rats against cardiotoxicity. Bemitradine also had a direct effect on the heart, as evidenced in an experiment in which bemitradine caused dose-related increases in the T-wave of the rat ECG complex. These data suggest that (1) both bemitradine and desethylbemitradine may be responsible for the cardiotoxicity, and the other downstream metabolites are not and (2) cardiotoxicity may be due to the combination of direct effects of bemitradine on the rat heart and the bemitradine-mediated release of adrenal epinephrine (a known cardiotoxin at high circulating levels).