Analgesic effect of local anaesthetic in haemorrhoid banding: systematic review and meta-analysis.

PURPOSE: Rubber band ligation of haemorrhoids can be,painful and there is no consensus regarding the optimal analgesic strategy. This study aims to determine whether there is a difference in post-procedural pain in adults undergoing haemorrhoid banding who have received local anaesthetic, a pudendal nerve block or no regional or local analgesia. METHODS: MEDLINE, Embase, Google Scholar and clinical trial registries were searched for randomised trials of local anaesthetic or pudendal nerve block use in banding. Primary outcomes were patient-reported pain scores. The quality of the evidence was assessed using the GRADE approach. RESULTS: Seven studies were included in the final review. No articles were identified that studied pudendal nerve blocks. The difference in numerical pain scores between treatment groups favoured the local anaesthetic group at all timepoints. The mean difference in scores on a 10-point scale was at 1 h,-1.43 (95% CI-2.30 to-0.56, p < 0.01, n = 342 (175 in treatment group)); 6 h,-0.52 (95% CI-1.04 to 0.01, p = 0.05, n = 250 (130 in treatment group)); and 24 h,-0.31 (95% CI-0.82 to 0.19, p = 0.86, n = 247 (127 in treatment group)). Of reported safety outcomes, vasovagal symptoms proceeded to meta-analysis, with a risk ratio of 1.01 (95% CI 0.64-1.60). The quality of the evidence was rated down to 'low' due to inconsistency and imprecision. CONCLUSION: This review supports the use of LA for reducing early post-procedural pain following haemorrhoid banding. The evidence was limited by small sample sizes and substantial heterogeneity across studies. REGISTRATION: PROSPERO (ID CRD42022322234).

Navigating parenthood in the surgical profession: mixed-methods study.

BACKGROUND: Significant barriers exist to surgeons being good parents and parents being good surgeons, and these barriers are heightened for women. Considering the gender balance now present in postgraduate medical schools, it is critical that these barriers are overcome if surgery is to attract and retain applicants. This study aimed to investigate patterns of parenthood in surgery, explore associated attitudes and experiences, and identify barriers and solutions within an Australian and New Zealand context. METHODS: Surgeons and trainees were invited to participate in a survey and focus groups. Quantitative results were described, and textual responses and focus group transcriptions were analysed thematically. RESULTS: There were 261 survey respondents (62.8 per cent women, 37.2 per cent men) and six focus groups (34 participants). Of the survey respondents, 79.6 per cent of women and 86.5 per cent of men had children. Women were more likely to time childbirth around training or work, and most respondents without children attributed this to their career. Tensions between parenthood and surgery engendered guilt for surgeon-parents. Parenthood was often the 'elephant in the room' in training and employment discussions. Breaking the silence around parenthood and surgery made it more acceptable, normalising positive behaviour changes. The major barrier to parenthood and surgery was the lack of flexible training opportunities. Participants called for top-down establishment of mandated, stand-alone, permanent part-time training positions. CONCLUSION: Many barriers to parenthood in surgery are created by rigid workplace and professional structures that are reflective of male-dominated historical norms. A willingness to be flexible, innovative and rethink models of training and employment is central to change.

It is difficult for surgeons to be good parents and parents to be good surgeons. This is a problem because it means that fewer doctors may want to be surgeons. This study asked surgeons and trainee surgeons what it is like to do their job as a parent. They were asked about this on their own and in groups. It was found that it is more difficult for female surgeons to have children than male surgeons. Surgeons with children feel guilty that they are not able to do a good job both at work and at home. Surgeons often avoid talking about parenting at work, because it is not normal to do so and they are afraid that it will have a negative effect on their career. If surgeons can work part-time while training, it would enable them to better balance their responsibilities as surgeons and parents. At the moment, there are not many opportunities to train part-time in Australia and New Zealand. This study suggests that surgeons and hospitals should make sure that this becomes accessible and normal.

Telomere Distribution in Human Sperm Heads and Its Relation to Sperm Nuclear Morphology: A New Marker for Male Factor Infertility?

Infertility is a problem affecting an increasing number of couples worldwide. Currently, marker tests for male factor infertility are complex, highly technical and relatively subjective. Up to 40% of cases of male factor infertility are currently diagnosed as idiopathic therefore, there is a clear need for further research into better ways of diagnosing it. Changes in sperm telomere length have been associated with infertility and closely linked to DNA damage and fragmentation, which are also known to be related to infertility. However, telomere distribution is a parameter thus far underexplored as an infertility marker. Here, we assessed morphological parameters of sperm nuclei in fertile control and male factor infertile cohorts. In addition, we used 2D and 3D fluorescence in situ hybridization (FISH) to compare telomere distribution between these two groups. Our findings indicate that the infertile cohort sperm nuclei were, on average, 2.9% larger in area and showed subtle differences in sperm head height and width. Telomeres were mainly distributed towards the periphery of the nuclei in the control cohort, with diminishing telomere signals towards the center of the nuclei. Sperm nuclei of infertile males, however, had more telomere signals towards the center of the nuclei, a finding supported by 3D imaging. We conclude that, with further development, both morphology and telomere distribution may prove useful investigative tools in the fertility clinic.

Mental health matters: a pilot study exploring the experiences and perspectives of individuals with complex communication needs.

Mental health and wellbeing are foundational in human interaction and life satisfaction. Persons with complex communication needs are at risk of reduced mental health and wellbeing. The aim of this project was to identify the facilitators and barriers that individuals with complex communication needs experience when attending to their mental health and wellbeing. A qualitative study design using a phenomenological approach was utilized. Data was collected through in-depth interviews with three participants with complex communication needs, observation, and reflexive journaling. An inductive process of cross-case thematic analysis identified common barriers and facilitators experienced by the participants when addressing mental health and wellbeing. The opportunity barriers described in Beukelman and Mirenda's  Participation Model were applied to classify the assistive and obstructive roles of communication partners. Barriers and facilitators to obtaining assistance for mental health and wellbeing related predominantly to communication partners' skills, attitudes, and support practices. The findings highlight a need to equip individuals with complex communication needs, carers, support workers, and mental health professionals with the knowledge, skills, and attitudes to promote mental health and wellbeing among this population.

The bile salt sodium taurocholate induces Campylobacter jejuni outer membrane vesicle production and increases OMV-associated proteolytic activity.

Campylobacter jejuni, the leading cause of bacterial acute gastroenteritis worldwide, secretes an arsenal of virulence-associated proteins within outer membrane vesicles (OMVs). C. jejuni OMVs contain three serine proteases (HtrA, Cj0511, and Cj1365c) that cleave the intestinal epithelial cell (IEC) tight and adherens junction proteins occludin and E-cadherin, promoting enhanced C. jejuni adhesion to and invasion of IECs. C. jejuni OMVs also induce IECs innate immune responses. The bile salt sodium taurocholate (ST) is sensed as a host signal to coordinate the activation of virulence-associated genes in the enteric pathogen Vibrio cholerae. In this study, the effect of ST on C. jejuni OMVs was investigated. Physiological concentrations of ST do not have an inhibitory effect on C. jejuni growth until the early stationary phase. Coculture of C. jejuni with 0.1% or 0.2% (w/v) ST stimulates OMV production, increasing both lipid and protein concentrations. C. jejuni ST-OMVs possess increased proteolytic activity and exhibit a different protein profile compared to OMVs isolated in the absence of ST. ST-OMVs exhibit enhanced cytotoxicity and immunogenicity to T84 IECs and enhanced killing of Galleria mellonella larvae. ST increases the level of mRNA transcripts of the OMVs-associated serine protease genes and the cdtABC operon that encodes the cytolethal distending toxin. Coculture with ST significantly enhances the OMVs-induced cleavage of E-cadherin and occludin. C. jejuni OMVs also cleave the major endoplasmic reticulum chaperone protein BiP/GRP78 and this activity is associated with the Cj1365c protease. These data suggest that C. jejuni responds to the presence of physiological concentrations of the bile salt ST that increases OMV production and the synthesis of virulence-associated factors that are secreted within the OMVs. We propose that these events contribute to pathogenesis.

Implementation of CT-P13 via a Managed Switch Programme in Crohn's Disease: 12-Month Real-World Outcomes.

BACKGROUND: Switching from Remicade to CT-P13 allows for significant cost savings and has been shown to be non-inferior to continued therapy with Remicade for the treatment of Crohn's disease. AIM: The aim of this work was to prospectively evaluate clinical outcomes in a cohort of patients with Crohn's disease switching from Remicade to CT-P13. METHODS: A prospective service evaluation was performed. The Harvey-Bradshaw index, CRP, faecal calprotectin and serum for infliximab/antibody levels were collected prior to patients' final Remicade infusion and at 6 and 12 months after switching to CT-P13 as part of routine clinical care. All adverse events during follow-up were also recorded. RESULTS: One hundred and ten patients on Remicade switched to CT-P13. No significant difference was observed between the Harvey-Bradshaw Index (p = 0.07), CRP (p = 0.13), faecal calprotectin (p = 0.25) or trough infliximab levels (p = 0.47) comparing before and at 6 and 12 months after the switch to CT-P13. Seven patients developed new infliximab antibodies after switching from Remicade to CT-P13. The majority of patients remained on CT-P13 at 12 months (84.5%) and the rate of adverse events and serious adverse events was 53.8 and 13.5 per 100 patient-years of follow-up, respectively. Switching to CT-P13 resulted in a cost saving of approximately 46.4%. CONCLUSION: The transition to CT-P13 from Remicade for the treatment of Crohn's disease is safe and has no negative effect on clinical outcomes at 12 months.

Unexpected differential metabolic responses of Campylobacter jejuni to the abundant presence of glutamate and fucose.

INTRODUCTION: Campylobacter jejuni is the leading cause of foodborne bacterial enteritis in humans, and yet little is known in regard to how genetic diversity and metabolic capabilities among isolates affect their metabolic phenotype and pathogenicity. OBJECTIVES: For instance, the C. jejuni 11168 strain can utilize both L-fucose and L-glutamate as a carbon source, which provides the strain with a competitive advantage in some environments and in this study we set out to assess the metabolic response of C. jejuni 11168 to the presence of L-fucose and L-glutamate in the growth medium. METHODS: To achieve this, untargeted hydrophilic liquid chromatography coupled to mass spectrometry was used to obtain metabolite profiles of supernatant extracts obtained at three different time points up to 24 h. RESULTS: This study identified both the depletion and the production and subsequent release of a multitude of expected and unexpected metabolites during the growth of C. jejuni 11168 under three different conditions. A large set of standards allowed identification of a number of metabolites. Further mass spectrometry fragmentation analysis allowed the additional annotation of substrate-specific metabolites. The results show that C. jejuni 11168 upon L-fucose addition indeed produces degradation products of the fucose pathway. Furthermore, methionine was faster depleted from the medium, consistent with previously-observed methionine auxotrophy. CONCLUSIONS: Moreover, a multitude of not previously annotated metabolites in C. jejuni were found to be increased specifically upon L-fucose addition. These metabolites may well play a role in the pathogenicity of this C. jejuni strain.

Salmonella infection in grey seals (Halichoerus grypus), a marine mammal sentinel species: pathogenicity and molecular typing of Salmonella strains compared with human and livestock isolates.

Microbial pollution of the marine environment through land-sea transfer of human and livestock pathogens is of concern. Salmonella was isolated from rectal swabs of free-ranging and stranded grey seal pups (21.1%; 37/175) and compared with strains from the same serovars isolated from human clinical cases, livestock, wild mammals and birds in Scotland, UK to characterize possible transmission routes using pulsed-field gel electrophoresis and multi-locus variable number of tandem repeat analyses. A higher prevalence of Salmonella was found in pups exposed to seawater, suggesting that this may represent a source of this pathogen. Salmonella Bovismorbificans was the most common isolate (18.3% pups; 32/175) and was indistinguishable from isolates found in Scottish cattle. Salmonella Typhimurium was infrequent (2.3% pups; 4/175), mostly similar to isolates found in garden birds and, in one case, identical to a highly multidrug resistant strain isolated from a human child. Salmonella Haifa was rare (1.1% pups; 2/175), but isolates were indistinguishable from that of a human clinical isolate. These results suggest that S. Bovismorbificans may circulate between grey seal and cattle populations and that both S. Typhimurium and S. Haifa isolates are shared with humans, raising concerns of microbial marine pollution.

Pharmacological regimens for eradication of Helicobacter pylori: an overview of systematic reviews and network meta-analysis.

BACKGROUND: Approximately half of the world's population is infected with Helicobacter pylori (H.pylori), a bacterium shown to be linked with a series of gastrointestinal diseases. A growing number of systematic reviews (SRs) have been published comparing the effectiveness of different treatments for H.pylori infection but have not reached a consistent conclusion. The objective of this study is to provide an overview of SRs of pharmacological therapies for the eradication of H.pylori. METHODS: Major electronic databases were searched to identify relevant SRs published between 2002 and February 2016. Studies were considered eligible if they included RCTs comparing different pharmacological regimens for treating patients diagnosed as H.pylori infected and pooled the eradication rates in a meta-analysis. A modified version of the 'A Measurement Tool to Assess Systematic Reviews' (AMSTAR) was used to assess the methodological quality. A Bayesian random effects network meta-analysis (NMA) was conducted to compare the different proton pump inhibitors (PPI) within triple therapy. RESULTS: 30 SRs with pairwise meta-analysis were included. In triple therapy, the NMA ranked the esomeprazole to be the most effective PPI, followed by rabeprazole, while no difference was observed among the three old generations of PPI for the eradication of H.pylori. When comparing triple and bismuth-based therapy, the relative effectiveness appeared to be dependent on the choice of antibiotics within the triple therapy; moxifloxacin or levofloxacin-based triple therapy were both associated with greater effectiveness than bismuth-based therapy as a second-line treatment, while bismuth-based therapy achieved similar or greater eradication rate compared to clarithromycin-based therapy. Inconsistent findings were reported regarding the use of levofloxacin/moxifloxacin in the first-line treatment; this could be due to the varied resistant rate to different antibiotics across regions and populations. Critical appraisal showed a low-moderate level of overall methodological quality of included studies. CONCLUSIONS: Our analysis suggests that the new generation of PPIs and use of moxifloxacin or levofloxacin within triple therapy as second-line treatment were associated with greater effectiveness. Given the varied antibiotic resistant rate across regions, the appropriateness of pooling results together in meta-analysis should be carefully considered and the recommendation of the choice of antibiotics should be localized.

Evidence of land-sea transfer of the zoonotic pathogen Campylobacter to a wildlife marine sentinel species.

Environmental pollution often accompanies the expansion and urbanization of human populations where sewage and wastewaters commonly have an impact on the marine environments. Here, we explored the potential for faecal bacterial pathogens, of anthropic origin, to spread to marine wildlife in coastal areas. The common zoonotic bacterium Campylobacter was isolated from grey seals (Halichoerus grypus), an important sentinel species for environmental pollution, and compared to isolates from wild birds, agricultural sources and clinical samples to characterize possible transmission routes. Campylobacter jejuni was present in half of all grey seal pups sampled (24/50 dead and 46/90 live pups) in the breeding colony on the Isle of May (Scotland), where it was frequently associated with histological evidence of disease. Returning yearling animals (19/19) were negative for C. jejuni suggesting clearance of infection while away from the localized colony infection source. The genomes of 90 isolates from seals were sequenced and characterized using a whole-genome multilocus sequence typing (MLST) approach and compared to 192 published genomes from multiple sources using population genetic approaches and a probabilistic genetic attribution model to infer the source of infection from MLST data. The strong genotype-host association has enabled the application of source attribution models in epidemiological studies of human campylobacteriosis, and here assignment analyses consistently grouped seal isolates with those from human clinical samples. These findings are consistent with either a common infection source or direct transmission of human campylobacter to grey seals, raising concerns about the spread of human pathogens to wildlife marine sentinel species in coastal areas.

Use of pudendal nerve blocks in rubber band ligation of haemorrhoids: an Australia-wide cross-sectional analysis.

BACKGROUND: Surgeons vary in their approach to preventing pain post rubber band ligation (RBL) of haemorrhoids, with pudendal nerve blocks (PNB) being one analgesic strategy. No data exists on how commonly PNBs are used in RBL in Australia, and whether use varies by year and patient and hospital characteristics. METHODS: Aggregate data from the National Hospital Morbidity Database was obtained for all admissions for RBL in Australia from 2012 to 2021, with and without a PNB, overall and in relation to sex, age group, hospital remoteness, hospital sector, and year of procedure. Adjusted relative risks (adj. RR) of PNB were estimated using Poisson regression, mutually adjusting for all variables. RESULTS: Of the 346 542 admissions for RBL, 14013 (4.04%) involved a PNB. The proportion of patients receiving a PNB increased between 2012-2013 and 2020-2021, from 1.62% to 6.63% (adj. RR 3.99, CI 3.64-4.36). Patients most likely to receive a PNB were female (adj. RR 1.10; CI 1.07-1.14) aged 25-34 years (adj. RR 1.13; CI 1.01-1.26); in major-city (adj. RR 1.25 CI 1.20-1.30) and private hospitals (adj. RR 3.28 CI 3.13-3.45). CONCLUSION: This is the first published analysis of the use of PNB in RBL. Pudendal nerve block use has increased over time, with substantial variation in practice. Blocks were more than three times as likely to be used in private compared to public hospitals. If evidence supporting PNB use is established, equitable access to the procedure should be pursued.

Variations in antimicrobial resistance genes present in the rectal faeces of seals in Scottish and Liverpool Bay coastal waters.

Antibiotic resistance genes originating from human activity are considered important environmental pollutants. Wildlife species can act as sentinels for coastal environmental contamination and in this study we used qPCR array technology to investigate the variety and abundance of antimicrobial resistance genes (ARGs), mobile genetic elements (MGEs) and integrons circulating within seal populations both near to and far from large human populations located around the Scottish and northwest English coast. Rectal swabs were taken from 50 live grey seals and nine live harbour seals. Nucleic acids were stabilised upon collection, enabling extraction of sufficient quality and quantity DNA for downstream analysis. 78 ARG targets, including genes of clinical significance, four MGE targets and three integron targets were used to monitor genes within 22 sample pools. 30 ARGs were detected, as well as the integrons intl1 and intl2 and tnpA transposase. Four ß-lactam, nine tetracycline, two phenicol, one trimethoprim, three aminoglycoside and ten multidrug resistance genes were detected as well as mcr-1 which confers resistance to colistin, an important drug of last resort. No sulphonamide, vancomycin, macrolide, lincosamide or streptogramin B (MLSB) resistance genes were detected. Resistance genes were detected in all sites but the highest number of ARGs (n = 29) was detected in samples derived from grey seals on the Isle of May, Scotland during the breeding season, and these genes also had the highest average abundance in relation to the 16S rRNA gene. This pilot study demonstrates the effectiveness of a culture-independent workflow for global analysis of ARGs within the microbiota of live, free-ranging, wild animals from habitats close to and remote from human habitation, and highlights seals as a valuable indicator species for monitoring the presence, abundance and land-sea transference of resistance genes within and between ecosystems.

Tailoring follow-up endoscopy in patients with severe oesophagitis.

Objective: We aimed to investigate the clinical utility of follow-up oesophagogastroduodenoscopy (OGD2) in patients with severe oesophagitis (Los Angeles grades C or D) through evaluating the yield of Barrett's oesophagus (BO), cancer, dysplasia and strictures. Second, we aimed to determine if the Clinical Frailty Scale (CFS) may be used to identify patients to undergo OGD2s. Design/method: Patients in NHS Lothian with an index OGD (OGD1) diagnosis of severe oesophagitis between 1 January 2014 and 31 December 2015 were identified. Univariate analysis identified factors associated with grade. Patients were stratified by frailty and a diagnosis of stricture, cancer, dysplasia and BO. Results: In total 964 patients were diagnosed with severe oesophagitis, 61.7% grade C and 38.3% grade D. The diagnostic yield of new pathology at OGD2 was 13.2% (n=51), new strictures (2.3%), dysplasia (0.5%), cancer (0.3%) and BO (10.1%). A total of 140 patients had clinical frailty (CFS score ≥5), 88.6% of which were deceased at review (median of 76 months). In total 16.4% of frail patients underwent OGD2s and five new pathologies were diagnosed, none of which were significantly associated with grade. Among non-frail patients at OGD2, BO was the only pathology more common (p=0.010) in patients with grade D. Rates of cancer, dysplasia and strictures did not vary significantly between grades. Conclusion: Our data demonstrate that OGD2s in patients with severe oesophagitis may be tailored according to clinical frailty and only be offered to non-frail patients. In non-frail patients OGD2s have similar pick-up rates of sinister pathology in both grades of severe oesophagitis.

Improving communication access in psychoeducational interventions for people with complex communication needs: a scoping review and stakeholder consultation.

PURPOSE: Psychoeducational interventions are commonly used to improve mental health among the general population; however, their application among people with complex communication needs is under explored. This scoping review aims to identify the psychoeducational interventions utilised with people with complex communication needs, any adaptations to improve communication access, and outcomes for this population. MATERIALS AND METHODS: The scoping review was conducted using the Arksey and O'Malley guidelines and included stakeholder consultations. A systematic search of the literature was conducted. Stakeholder consultations were conducted via semi-structured interviews with informants from three populations: people with complex communication needs, everyday communication partners and mental health workers. RESULTS: The search yielded 2112 articles. Twenty-four articles were retained for data extraction. Numerical analysis provided an overview of the existing literature. Thematic analysis highlighted the range of communication access strategies applied within psychoeducational interventions. Common aims and outcomes of interventions occurred across three interrelated themes: education, symptom reduction, and improved coping and wellbeing. Stakeholder consultations enabled contextualisation of literature. CONCLUSIONS: People with complex communication needs may benefit from psychoeducational interventions when effective, personalised communication access strategies are employed. Future research should include lived-experience perspectives to ensure the relevance of communication access strategies in mental health support.Implications for rehabilitationThis scoping review adds to the evidence base supporting equitable access to mental health support for people with complex communication needs.A range of specific strategies are presented for mental health workers to consider when working with people with complex communication needs.Positive behaviour support (PBS) practitioners must be equipped to address the psychoeducational and mental health support requirements of people with complex communication needs.

Training primary care staff in delivering the primary care consultation remotely: a systematic review.

BACKGROUND: Remote consultation is widely used in primary care, and its use has increased greatly since the onset of the COVID-19 pandemic. Despite this, primary care clinicians lack formal training in delivering remote consultation. There is a need to understand how training might best be delivered, and what evidence there is to support this. AIM: To summarise existing published literature about training primary care staff in conducting primary care consultation remotely, to outline which models of training may be effective, and to identify unanswered questions for future research. DESIGN & SETTING: Systematic review of English language studies in primary care included in Medline (Ovid), Cochrane Database, PubMed, Embase (Ovid), Web of Science, and CINAHL from 2010-2021; and in Google results from 2010-2022. METHOD: Databases were searched using a predefined search strategy. Title, abstract, and full-text screening was conducted to identify eligible studies for inclusion in the review. The quality of included studies was assessed, and findings were synthesised to answer the research questions. RESULTS: We included 10 studies. Seven examined training on remote consultation with trainee GPs or residents, and three examined training on remote consultation with qualified primary care clinicians. Training described led to positive change overall, including increased confidence and self-efficacy in delivering remote consultations. Furthermore, trainees reported increased use of remote consultation, increased efficiency, and increased engagement from patients. Studies where training involved workshops or didactic learning alongside experiential learning resulted in more positive feelings and more confidence about how technology could aid consultations. CONCLUSION: There is limited evidence on training primary care staff in conducting remote consultation. Available evidence indicates that training has a positive impact on the ability of clinicians and staff to deliver remote consultation.

Local anaesthetic infiltration in rubber band ligation of rectal haemorrhoids: study protocol for a three-arm, double-blind randomised controlled trial (PLATIPUS trial).

INTRODUCTION: Rubber band ligation ('banding') is a common approach for the management of symptomatic haemorrhoids. However, up to 90% of patients experience postprocedural pain, and there is no consensus regarding the optimal analgesic strategy. In practice, patients may receive submucosal local anaesthetic, pudendal nerve block or routine periprocedural analgesia. The aim of this study is to compare the efficacy of submucosal local anaesthetic, pudendal nerve block and routine analgesia for postprocedural pain in patients undergoing haemorrhoid banding. METHODS AND ANALYSIS: This is a multicentre, prospective, three-arm, double-blind randomised controlled trial of adults booked for haemorrhoid banding. Participants will be randomised to one of three groups in a 1:1:1 ratio: (1)submucosal bupivacaine injection; (2) pudendal nerve ropivacaine injection and (3) no local anaesthetic. The primary outcome is patient reported postprocedural pain (scored 0-10) from 30 min to 2 weeks. Secondary outcomes include postprocedural analgesia use, time to discharge, patient satisfaction, time to return to work and complications. A sample size of 120 patients is required to achieve statistical significance. ETHICS AND DISSEMINATION: This study received Human Research Ethics Approval from the Austin Health Human Research Ethics Committee (March 2022). Trial results will be submitted to a peer-reviewed journal, and presented at academic meetings. A summary of the trial results will be made available to study participants on request. TRIAL REGISTRATION NUMBER: ACTRN12622000006741p.

Campylobacter jejuni outer membrane vesicles play an important role in bacterial interactions with human intestinal epithelial cells.

Campylobacter jejuni is the most prevalent cause of food-borne gastroenteritis in the developed world; however, the molecular basis of pathogenesis is unclear. Secretion of virulence factors is a key mechanism by which enteric bacterial pathogens interact with host cells to enhance survival and/or damage the host. However, C. jejuni lacks the virulence-associated secretion systems possessed by other enteric pathogens. Many bacterial pathogens utilize outer membrane vesicles (OMVs) for delivery of virulence factors into host cells. In the absence of prototypical virulence-associated secretion systems, OMVs could be an important alternative for the coordinated delivery of C. jejuni proteins into host cells. Proteomic analysis of C. jejuni 11168H OMVs identified 151 proteins, including periplasmic and outer membrane-associated proteins, but also many determinants known to be important in survival and pathogenesis, including the cytolethal distending toxin (CDT). C. jejuni OMVs contained 16 N-linked glycoproteins, indicating a delivery mechanism by which these periplasm-located yet immunogenic glycoproteins can interact with host cells. C. jejuni OMVs possess cytotoxic activity and induce a host immune response from T84 intestinal epithelial cells (IECs), which was not reduced by OMV pretreatment with proteinase K or polymyxin B prior to coincubation with IECs. Pretreatment of IECs with methyl-beta-cyclodextrin partially blocks OMV-induced host immune responses, indicating a role for lipid rafts in host cell plasma membranes during interactions with C. jejuni OMVs. OMVs isolated from a C. jejuni 11168H cdtA mutant induced interleukin-8 (IL-8) to the same extent as did wild-type OMVs, suggesting OMV induction of IL-8 is independent of CDT.

Docking and molecular dynamics studies of human ezrin protein with a modelled SARS-CoV-2 endodomain and their interaction with potential invasion inhibitors.

Human ezrin protein interacts with SARS-CoV S endodomain and restricts virus fusion, entry, and early events of infection. In general, their binding strength and their structural stability determines their successful entry into the host cells. However, the binding affinity of these two endodomains with the ezrin protein has been elusive due to a paucity of knowledge on the 3D structure. This study modelled the endodomains of both SARS-CoV-1 and SARS-CoV-2 and then docked these models with human ezrin protein. This study establishes that the modelled endodomains of both SARS-CoV-1 and SARS-Cov-2 consisted of three disulphide bridges for self-stabilization. Protein-protein docking listed four salt bridges with a higher buried surface area between ezrin-SARS-CoV-1 endodomain compared to that of ezrin-SARS-CoV-2 with six salt bridges with lower buried surface area. Molecular simulation of the ezrin-SARS-CoV-1 endodomain showed better structural stability with lower Root Mean Square Deviation score compared to that of ezrin-SARS-CoV-2 endodomain due to the substitution of alanine with cysteine residue. Protein-ligand docking studies confirmed better ezrin-drug interaction for quercetin, minocycline, calcifediol, calcitriol, selamectin, ivermectin and ergocalciferol. However, protein-ligand simulation confirmed strong drug-protein interaction during simulation for all the above-listed drugs except for ergocalciferol which could not establish its interaction with the protein during simulation. Strong drug binding within the active site pocket therefore restricts the interaction of viral endodomain and simultaneously stabilizes the ezrin protein. Furthermore, the higher stability between the ezrin after their interaction with the drug moiety could restrict the virus fusion and the infection. This study provides a basis for further development of these drug molecules to clinical trials aiming to identify potential drug molecules which can treat COVID-19 infection.

A comparative study of the fecal microbiota of gray seal pups and yearlings - a marine mammal sentinel species.

Gray seals (Halichoerus grypus) can act as sentinel species reflecting the condition of the environment they inhabit. Our previous research identified strains of pathogenic Campylobacter and Salmonella, originating from both human and agricultural animal hosts, on rectal swabs from live gray seal (H. grypus) pups and yearlings on the Isle of May, Scotland, UK. We examined rectal swabs from the same pup (n = 90) and yearling (n = 19) gray seals to gain further understanding into the effects of age-related changes (pup vs. yearling) and three different natal terrestrial habitats on seal pup fecal microbiota. DNA was extracted from a subset of rectal swabs (pups n = 23, yearlings n = 9) using an optimized procedure, and the V4 region of the 16S ribosomal RNA gene was sequenced to identify each individual's microbiota. Diversity in pup samples was lower (3.92 ± 0.19) than yearlings (4.66 ± 0.39) although not significant at the p = 0.05 level (p = 0.062) but differences in the composition of the microbiota were (p < 0.001). Similarly, differences between the composition of the microbiota from pups from three different terrestrial habitats (Pilgrim's Haven [PH], Rona Rocks [RR], and Tarbet Slope [TS]) were highly significant (p < 0.001). Pairwise tests showed significant differences between all three habitats: PH versus TS (p = 0.019), PH versus RR (p = 0.042) and TS versus RR (p = 0.020). This preliminary study suggests a general trend, that seal microbiomes are modified by both age and, in pups, different terrestrial habitats. Furthermore, knowledge of the microbiota species present has the potential to be used in determining the environmental quality index.