Maggots and wound healing: the effects of Lucilia sericata larval secretions upon interactions between human dermal fibroblasts and extracellular matrix proteins

The introduction of necrophagous fly larvae (maggots) into chronic wounds for the purpose of inducing healing is an ancient practice that has recently undergone a renaissance in Western medicine. Through clinical observations, maggots are broadly recognised to debride the wound of necrotic tissue, cleanse the wound of infection and promote granulation tissue formation. Despite such recognition, little research at the biological level has been undertaken to identify the mechanisms by which maggots accomplish such feats. The dermal fibroblast is a major cellular component of granulation tissue and as such, its migration into the wound plays a vital role in new tissue growth. Fibroblast migration is directed by the composition of the extracellular matrix. Maggot secretions contain proteolytic enzymes that are active against a variety of extracellular matrix proteins which are present at the wound site. Hence, this thesis focused upon the effects of maggot secretions on human dermal fibroblast adhesion and migration in the presence of common extracellular matrix proteins. This was with the aim of elucidating the mechanisms by which maggots stimulate tissue formation within the wound and from there, developing new products that may be used to promote wound healing. Experiments showed that maggot secretions modulated fibroblast adhesion to tissue culture plastic surfaces and to surfaces coated with collagen and particularly fibronectin. Modification of the protein-coated surface by enzymes present within the secretion appeared to play a role. Fibroblast migration upon a fibronectin-coated surface was enhanced in the presence of maggot secretions. The same also occurred in the presence of a higher concentration of secretions when the cells were located within a three-dimensional environment comprising collagen gel and fibronectin. Evidence suggested that this may have been associated with enhanced matrix re-modelling

Maggots and wound healing: the effects of Lucilia sericata larval secretions upon interactions between human dermal fibroblasts and extracellular matrix proteins

The introduction of necrophagous fly larvae (maggots) into chronic wounds for the purpose of inducing healing is an ancient practice that has recently undergone a renaissance in Western medicine. Through clinical observations, maggots are broadly recognised to debride the wound of necrotic tissue, cleanse the wound of infection and promote granulation tissue formation. Despite such recognition, little research at the biological level has been undertaken to identify the mechanisms by which maggots accomplish such feats. The dermal fibroblast is a major cellular component of granulation tissue and as such, its migration into the wound plays a vital role in new tissue growth. Fibroblast migration is directed by the composition of the extracellular matrix. Maggot secretions contain proteolytic enzymes that are active against a variety of extracellular matrix proteins which are present at the wound site. Hence, this thesis focused upon the effects of maggot secretions on human dermal fibroblast adhesion and migration in the presence of common extracellular matrix proteins. This was with the aim of elucidating the mechanisms by which maggots stimulate tissue formation within the wound and from there, developing new products that may be used to promote wound healing. Experiments showed that maggot secretions modulated fibroblast adhesion to tissue culture plastic surfaces and to surfaces coated with collagen and particularly fibronectin. Modification of the protein-coated surface by enzymes present within the secretion appeared to play a role. Fibroblast migration upon a fibronectin-coated surface was enhanced in the presence of maggot secretions. The same also occurred in the presence of a higher concentration of secretions when the cells were located within a three-dimensional environment comprising collagen gel and fibronectin. Evidence suggested that this may have been associated with enhanced matrix re-modelling

Talk to us! Communication is a key factor in improving the comfort of MRI research participants

Context: Magnetic resonance imaging (MRI) is an invaluable diagnostic and research tool. Having an MRI scan is not always comfortable and may deter people from taking part in MRI research. Maximising comfort during scanning will improve participants' experiences and image quality. Objective: To define which factors are important for comfort during a research MRI scan by asking people who have participated in MRI research. Setting and participants: People who had participated in MRI research during the past two years were invited, as 'public advisors' to discuss their experiences together and agree on which factors are most important in ensuring comfort while participating in MRI research. Results: Public advisors ranked researcher-participant communication as the most important factor. In response, an example script to guide MRI researchers in communicating with participants was developed through close consultation between research staff, public advisors, and the public. This outlines the often-missing information necessary to convey to participants, including explaining the reasons behind instructions, managing expectations, providing reassurance, encouragement, and progress updates during scanning. Conclusions: Drawing upon personal experiences as MRI research participants, public advisors highlighted the importance of effective and ongoing researcher communication throughout. The example script may be used as a training tool for researchers to help ensure participants' comfort during scanning. Patient and public contribution: All contributors had previously taken part in MRI research. The project was co-designed, co-delivered and co-authored with a public research partner. Public advisors agreed key factors of importance. External public reviewers and public advisors reviewed example script drafts. Data Availability Statement No further data were generated in this patient and public consultation

the COMIT’ID study protocol for using a Delphi process and face-to-face meetings to establish consensus

Background The reporting of outcomes in clinical trials of subjective tinnitus indicates that many different tinnitus-related complaints are of interest to investigators, from perceptual attributes of the sound (e.g. loudness) to psychosocial impacts (e.g. quality of life). Even when considering one type of intervention strategy for subjective tinnitus, there is no agreement about what is critically important for deciding whether a treatment is effective. The main purpose of this observational study is, therefore to, develop Core Outcome Domain Sets for the three different intervention strategies (sound, psychological, and pharmacological) for adults with chronic subjective tinnitus that should be measured and reported in every clinical trial of these interventions. Secondary objectives are to identify the strengths and limitations of our study design for recruiting and reducing attrition of participants, and to explore uptake of the core outcomes. Methods The ‘Core Outcome Measures in Tinnitus: International Delphi’ (COMIT’ID) study will use a mixed-methods approach that incorporates input from health care users at the pre-Delphi stage, a modified three-round Delphi survey and final consensus meetings (one for each intervention). The meetings will generate recommendations by stakeholder representatives on agreed Core Outcome Domain Sets specific to each intervention. A subsequent step will establish a common cross-cutting Core Outcome Domain Set by identifying the common outcome domains included in all three intervention-specific Core Outcome Domain Sets. To address the secondary objectives, we will gather feedback from participants about their experience of taking part in the Delphi process. We aspire to conduct an observational cohort study to evaluate uptake of the core outcomes in published studies at 7 years following Core Outcome Set publication. Discussion The COMIT’ID study aims to develop a Core Outcome Domain Set that is agreed as critically important for deciding whether a treatment for subjective tinnitus is effective. Such a recommendation would help to standardise future clinical trials worldwide and so we will determine if participation increases use of the Core Outcome Set in the long term. Trial registration This project has been registered (November 2014) in the database of the Core Outcome Measures in Effectiveness Trials (COMET) initiative

Redesigning a Web-Based Stakeholder Consensus Meeting About Core Outcomes for Clinical Trials: Formative Feedback Study

Background: Clinical trials that assess the benefits and harms of an intervention do so by measuring and reporting outcomes. Inconsistent selection and diversity in the choice of outcomes makes it challenging to directly compare interventions. To achieve an agreed core set of outcomes, a consensus methodology is recommended comprising a web-based Delphi survey and a face-to-face consensus meeting. However, UK-government regulations to control the pandemic prohibited plans for a face-to-face consensus meeting as part of the Core Rehabilitation Outcome Set for Single-Sided Deafness (CROSSSD) study. Objective: An observational study evaluated the modifications taken by the CROSSSD study team to achieve consensus using web-based methods, but with minimal deviation from the original study protocol. Methods: The study team worked with healthcare users and professionals to translate the planned face-to-face consensus meeting in a web-based format, preserving key elements of the nominal group technique. A follow-up survey gathered evaluation feedback on the experience of the 22 participating members. Feedback covered (i) pre-meeting preparation, (ii) process of facilitated discussions and voting, (iii) ability to contribute, and (iv) perceived fairness of the outcome. Results: Overall, 53 out of 54 feedback responses agreed or strongly agreed with the statements given, indicating the web-based meeting achieved its original goals of open discussion, debate, and voting to agree a core outcome set for single-sided deafness. Hearing-impaired participants were fully engaged, but there were some methodological challenges. For the participants, challenges included building rapport, understanding, and delivering the tasks in hand. For the study team, challenges included the need for thorough preparation and managing the unpredictability of tasks on the day. Conclusion: Sharing our experiences and lessons learned can benefit future core outcome set developers. Overcoming the challenges of delivering a web-based consensus exercise in the face of the pandemic can be applied more generally to maximise inclusiveness, enhance geographical access, as well as to reduce research costs

The Core Rehabilitation Outcome Set for Single-Sided Deafness (CROSSSD) study: International consensus on outcome measures for trials of interventions for adults with single-sided deafness

Background: Single-sided deafness (SSD) has functional, psychological, and social consequences. Interventions for adults with SSD include hearing aids and auditory implants. Benefits and harms (outcome domains) of these interventions are until now reported inconsistently in clinical trials. Inconsistency in reporting outcome measures prevents meaningful comparisons or syntheses of trial results. The Core Rehabilitation Outcome Set for Single-Sided Deafness (CROSSSD) international initiative used structured communication techniques to achieve consensus among healthcare users and professionals working in the field of SSD. The novel contribution is a set of core outcome domains that experts agree are critically important to assess in all clinical trials of SSD interventions. Methods: A long list of candidate outcome domains compiled from a systematic review and published qualitative data, informed the content of a two-round online Delphi survey. Overall, 308 participants from 29 countries were enrolled. Of those, 233 participants completed both rounds of the survey and scored each outcome domain on a 9-point scale. The set of core outcome domains was finalised via a web-based consensus meeting with 12 participants. Votes involved all stakeholder groups, with an approximate 2:1 ratio of professionals to healthcare users participating in the Delphi survey, and a 1:1 ratio participating in the consensus meeting. Results: The first round of the survey listed 44 potential outcome domains, organised thematically. A further five outcome domains were included in Round 2 based on participant feedback. The structured voting at round 2 identified 17 candidate outcome domains which were voted on at the consensus meeting. Consensus was reached for a core outcome domain set including three outcome domains: spatial orientation, group conversations in noisy social situations, and impact on social situations. Seventy-seven percent of the remaining Delphi participants agreed with this core outcome domain set. Conclusions: Adoption of the internationally agreed core outcome domain set would promote consistent assessment and reporting of outcomes that are meaningful and important to all relevant stakeholders. This consistency will in turn enable comparison of outcomes reported across clinical trials comparing SSD interventions in adults and reduce research waste. Further research will determine how those outcome domains should best be measured

Core outcome domains for early-phase clinical trials of sound-, psychology-, and pharmacology-based interventions to manage chronic subjective tinnitus in adults: the COMIT'ID study protocol for using a Delphi process and face-to-face meetings to establish consensus

Background: The reporting of outcomes in clinical trials of subjective tinnitus indicates that many different tinnitus-related complaints are of interest to investigators, from perceptual attributes of the sound (e.g. loudness) to psychosocial impacts (e.g. quality of life). Even when considering one type of intervention strategy for subjective tinnitus, there is no agreement about what is critically important for deciding whether a treatment is effective. The main purpose of this observational study is therefore to develop Core Outcome Domain Sets for the three different intervention strategies (sound, psychological, and pharmacological) for adults with chronic subjective tinnitus that should be measured and reported in every clinical trial of these interventions. Secondary objectives are to identify the strengths and limitations of our study design for recruiting and reducing attrition of participants, and to explore uptake of the core outcomes. Methods: The ‘Core Outcome Measures in Tinnitus: International Delphi’ (COMIT’ID) study will use a mixed methods approach that incorporates input from healthcare users at the pre-Delphi stage, a modified three round Delphi survey and final consensus meetings (one for each intervention). The meetings will generate recommendations by stakeholder representatives on agreed Core Outcome Domain Sets specific to each intervention. A subsequent step will establish a common cross-cutting Core Outcome Domain Set by identifying the common outcome domains included in all three intervention-specific Core Outcome Domain Sets. To address the secondary objectives, we will gather feedback from participants about their experience of taking part in the Delphi process. We aspire to conduct an observational cohort study to evaluate uptake of the core outcomes in published studies at 7 years following core outcome set publication. Discussion: The COMIT’ID study aims to develop a Core Outcome Domain Set that are agreed as critically important for deciding whether a treatment for subjective tinnitus is effective. Such a recommendation would help to standardise future clinical trials worldwide and so we will determine if participation increases use of the core outcome set in the long term. Trial registration: This project has been registered in the database of the Core Outcome Measures in Effectiveness Trials (COMET) initiative

The Core Rehabilitation Outcome Set for Single-Sided Deafness (CROSSSD) study: International consensus on outcome measures for trials of interventions for adults with single-sided deafness

Abstract Background Single-sided deafness (SSD) has functional, psychological, and social consequences. Interventions for adults with SSD include hearing aids and auditory implants. Benefits and harms (outcome domains) of these interventions are until now reported inconsistently in clinical trials. Inconsistency in reporting outcome measures prevents meaningful comparisons or syntheses of trial results. The Core Rehabilitation Outcome Set for Single-Sided Deafness (CROSSSD) international initiative used structured communication techniques to achieve consensus among healthcare users and professionals working in the field of SSD. The novel contribution is a set of core outcome domains that experts agree are critically important to assess in all clinical trials of SSD interventions. Methods A long list of candidate outcome domains compiled from a systematic review and published qualitative data, informed the content of a two-round online Delphi survey. Overall, 308 participants from 29 countries were enrolled. Of those, 233 participants completed both rounds of the survey and scored each outcome domain on a 9-point scale. The set of core outcome domains was finalised via a web-based consensus meeting with 12 participants. Votes involved all stakeholder groups, with an approximate 2:1 ratio of professionals to healthcare users participating in the Delphi survey, and a 1:1 ratio participating in the consensus meeting. Results The first round of the survey listed 44 potential outcome domains, organised thematically. A further five outcome domains were included in Round 2 based on participant feedback. The structured voting at round 2 identified 17 candidate outcome domains which were voted on at the consensus meeting. Consensus was reached for a core outcome domain set including three outcome domains: spatial orientation, group conversations in noisy social situations, and impact on social situations. Seventy-seven percent of the remaining Delphi participants agreed with this core outcome domain set. Conclusions Adoption of the internationally agreed core outcome domain set would promote consistent assessment and reporting of outcomes that are meaningful and important to all relevant stakeholders. This consistency will in turn enable comparison of outcomes reported across clinical trials comparing SSD interventions in adults and reduce research waste. Further research will determine how those outcome domains should best be measured

Abstracts from the NIHR INVOLVE Conference 2017

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Promotion of Human Dermal Fibroblast Migration, Matrix Remodelling and Modification of Fibroblast Morphology within a Novel 3D Model by Lucilia sericata Larval Secretions

Lucilia sericata larvae, or green bottle fly maggots are applied to chronic wounds to aid healing. Previously, our laboratory has characterized the enzymatic activities present within maggot excretions/secretions (ES). Since then, we have related these to the degradation of extracellular matrix components, alteration of human, dermal fibroblast adhesion to surfaces and the stimulation of fibroblast migration within a two-dimensional in vitro assay. In this study, we developed a novel three-dimensional in vitro assay in which to observe fibroblast migration and morphology in response to maggot ES. Here, primary human foreskin fibroblasts were embedded within collagen gels containing fibronectin. Phase contrast and confocal microscopy were used in conjunction with image analysis software to examine and quantify aspects of fibroblast behavior. Our results showed that maggot ES stimulated fibroblast migration through the matrix and induced altered cell morphologies. Remodelling of the extracellular matrix located between individual fibroblasts was also induced, providing a mechanism by which cells may detect each other's presence over considerable distances. Thus, mechanisms by which maggots enhance tissue formation within wounds may be via the promotion of fibroblast motility, acceleration of extracellular matrix remodelling and coordination of cellular responses