Decoding human fetal liver haematopoiesis.

Definitive haematopoiesis in the fetal liver supports self-renewal and differentiation of haematopoietic stem cells and multipotent progenitors (HSC/MPPs) but remains poorly defined in humans. Here, using single-cell transcriptome profiling of approximately 140,000 liver and 74,000 skin, kidney and yolk sac cells, we identify the repertoire of human blood and immune cells during development. We infer differentiation trajectories from HSC/MPPs and evaluate the influence of the tissue microenvironment on blood and immune cell development. We reveal physiological erythropoiesis in fetal skin and the presence of mast cells, natural killer and innate lymphoid cell precursors in the yolk sac. We demonstrate a shift in the haemopoietic composition of fetal liver during gestation away from being predominantly erythroid, accompanied by a parallel change in differentiation potential of HSC/MPPs, which we functionally validate. Our integrated map of fetal liver haematopoiesis provides a blueprint for the study of paediatric blood and immune disorders, and a reference for harnessing the therapeutic potential of HSC/MPPs.

OPTIMAL: An OPTimized Imaging Mass cytometry AnaLysis framework for benchmarking segmentation and data exploration.

Analysis of imaging mass cytometry (IMC) data and other low-resolution multiplexed tissue imaging technologies is often confounded by poor single-cell segmentation and suboptimal approaches for data visualization and exploration. This can lead to inaccurate identification of cell phenotypes, states, or spatial relationships compared to reference data from single-cell suspension technologies. To this end we have developed the "OPTimized Imaging Mass cytometry AnaLysis (OPTIMAL)" framework to benchmark any approaches for cell segmentation, parameter transformation, batch effect correction, data visualization/clustering, and spatial neighborhood analysis. Using a panel of 27 metal-tagged antibodies recognizing well-characterized phenotypic and functional markers to stain the same Formalin-Fixed Paraffin Embedded (FFPE) human tonsil sample tissue microarray over 12 temporally distinct batches we tested several cell segmentation models, a range of different arcsinh cofactor parameter transformation values, 5 different dimensionality reduction algorithms, and 2 clustering methods. Finally, we assessed the optimal approach for performing neighborhood analysis. We found that single-cell segmentation was improved by the use of an Ilastik-derived probability map but that issues with poor segmentation were only really evident after clustering and cell type/state identification and not always evident when using "classical" bivariate data display techniques. The optimal arcsinh cofactor for parameter transformation was 1 as it maximized the statistical separation between negative and positive signal distributions and a simple Z-score normalization step after arcsinh transformation eliminated batch effects. Of the five different dimensionality reduction approaches tested, PacMap gave the best data structure with FLOWSOM clustering out-performing phenograph in terms of cell type identification. We also found that neighborhood analysis was influenced by the method used for finding neighboring cells with a "disc" pixel expansion outperforming a "bounding box" approach combined with the need for filtering objects based on size and image-edge location. Importantly, OPTIMAL can be used to assess and integrate with any existing approach to IMC data analysis and, as it creates .FCS files from the segmentation output and allows for single-cell exploration to be conducted using a wide variety of accessible software and algorithms familiar to conventional flow cytometrists.

Are Deep Odontogenic Infections Associated With an Increased Risk for Sepsis?

BACKGROUND: Quick Sequential Organ Failure Assessment (qSOFA) is recommended to identify sepsis. Odontogenic infection (OI) can progress to sepsis, causing systematic inflammatory complications or organ failure. PURPOSE: The purpose of the study was to measure the association between OI location and risk for sepsis at admission. STUDY DESIGN, SETTING, AND SAMPLE: This retrospective cohort study included subjects treated for OI at Baylor University Medical Center in Dallas, TX, from January 9, 2019 to July 30, 2022. Subjects > 18 years old who were treated under general anesthesia were included. OI limited to periapical, vestibular, buccal, and/or canine spaces were excluded from the sample. PREDICTOR VARIABLE: The primary predictor variable was OI anatomic location (superficial or deep). Superficial OI infection includes submental, submandibular, sublingual, submasseteric, and/or superficial temporal spaces. Deep OI includes pterygomandibular, deep temporal, lateral pharyngeal, retropharyngeal, pretracheal, and/or prevertebral. MAIN OUTCOME VARIABLES: The primary outcome variable was risk for sepsis measured using a qSOFA score (0 to 3). A higher score (>0) indicates the patient has a high risk for sepsis. COVARIATES: Covariates were demographics, clinical, laboratory, and radiological findings, antibiotic route, postoperative endotracheal intubation, tracheostomy, intensive care unit, admission, and length of stay. ANALYSES: Descriptive and bivariate analyses were performed. A χ2 test was used for categorical variables. The Mann-Whitney U test was used for continuous variables. Statistical significance was P < .05. RESULTS: The sample was composed of 168 subjects with a mean age of 42.8 ± 21.5 and 69 (48.6%) subjects were male. There were 11 (6.5%) subjects with a qSOFA score > 0. The relative risk of a qSOFA > 0 for a deep OI is 5.4 times greater than for a superficial OI (136 (95.8) versus 21 (80.8%): RR (95% confidence interval): 5.4 (1.51 to 19.27), P = .004). After adjusting for age, sex, American Society of Anesthesiologists score, and involved anatomical spaces, there was a significant correlation between laterality and the number of involved anatomical spaces and qSOFA score (odd ratio = 9.13, 95% confidence interval: 2.48 to 33.55, adjusted P = <.001). CONCLUSION AND RELEVANCE: The study findings suggest that the OI location is associated with the qSOFA score >0.

High Proportions of Newly Detected Visible Lesions and Pathology Grade Change Among Patients with Barrett's Esophagus Referred to Expert Centers.

BACKGROUND AND AIMS: Endoscopic eradication therapy for Barrett's esophagus (BE)-related neoplasia is increasingly being performed at tertiary and community centers. While it has been suggested that these patients should be evaluated at expert centers, the impact of this practice has not been evaluated. We aimed to assess the impact of referral of BE-related neoplasia patients to expert centers by assessing the proportion of patients with change in pathological diagnosis and visible lesions detected. METHODS: Multiple databases were searched until December 2021 for studies of patients with BE referred from the community to expert center. The proportions of pathology grade change and newly detected visible lesions at expert centers were pooled using a random-effects model. Subgroup analyses were performed based on baseline histology and other relevant factors. RESULTS: Twelve studies were included (1630 patients). The pooled proportion of pathology grade change after expert pathologist review was 47% (95% CI 34-59%) overall and 46% (95% CI 31-62%) among patients with baseline low-grade dysplasia. When upper endoscopy was repeated at an expert center, the pooled proportion of pathology grade change was still high 47% (95% 26-69%) overall and 40% (95% CI 34-45%) among patients with baseline LGD. The pooled proportion of newly detected visible lesions was 45% (95% CI 28-63%) and among patients referred with LGD was 27% (95% CI 22-32%). CONCLUSION: An alarmingly high proportion of newly detected visible lesions and pathology grade change were found when patients were referred to expert centers supporting the need for centralized care for BE-related neoplasia patients.

The Clinical Observership Program: A Valuable Experience for Oral & Maxillofacial Surgery Residents.

PURPOSE: Training during oral and maxillofacial surgery residency must include exposure to the scope of the specialty, but success in practice often requires particular experience and knowledge of complex oral regenerative procedures such as bone grafting and implant surgery, as well as practice management. Osteo Science Foundation created the Clinical Observership Program (COP) in 2017 to provide residents the opportunity to spend several weeks in an established oral and maxillofacial surgery practice to increase experience in these areas. The purpose of this study is to report the results of a survey of all resident participants in the COP from 2017 to 2021 in which participants were asked to rate their experience numerically. MATERIALS AND METHODS: This is an institutional retrospective case series completed via an electronic survey sent to all participants in the COP from 2017 to 2021. The primary outcome is the subjective assessment of the COP based on six questions in which the respondent was asked to rate the program on a scale of 1 to 10 (10 being best). Categories included: 1) Did the program achieve expectations? 2) Was adequate time spent with the mentor? 3) Did you observe/participate in a variety of procedures? 4) Did the mentor provide additional didactic education? 5) Did you learn about practice management? and 6) How would you rate the overall experience? Descriptive statistics including mean score and standard deviation of each question were calculated, and no other covariates were analyzed. RESULTS: All 55 participants in the COP from 2017 to 2021 were contacted and 55 complete responses were received. The overall mean score for all categories rated by the residents was 9.63, the mean rating for questions 1 to 6 were 9.55, 9.89, 9.21, 9.60, 9.69, and 9.86 respectively, and the range of scores was 7 to 10. CONCLUSION: Overall, residents rated the COP experience highly. This survey indicates that the COP is a valuable supplemental experience in oral and maxillofacial surgery resident education.

CXCR2 inhibition enables NASH-HCC immunotherapy.

OBJECTIVE: Hepatocellular carcinoma (HCC) is increasingly associated with non-alcoholic steatohepatitis (NASH). HCC immunotherapy offers great promise; however, recent data suggests NASH-HCC may be less sensitive to conventional immune checkpoint inhibition (ICI). We hypothesised that targeting neutrophils using a CXCR2 small molecule inhibitor may sensitise NASH-HCC to ICI therapy. DESIGN: Neutrophil infiltration was characterised in human HCC and mouse models of HCC. Late-stage intervention with anti-PD1 and/or a CXCR2 inhibitor was performed in murine models of NASH-HCC. The tumour immune microenvironment was characterised by imaging mass cytometry, RNA-seq and flow cytometry. RESULTS: Neutrophils expressing CXCR2, a receptor crucial to neutrophil recruitment in acute-injury, are highly represented in human NASH-HCC. In models of NASH-HCC lacking response to ICI, the combination of a CXCR2 antagonist with anti-PD1 suppressed tumour burden and extended survival. Combination therapy increased intratumoural XCR1+ dendritic cell activation and CD8+ T cell numbers which are associated with anti-tumoural immunity, this was confirmed by loss of therapeutic effect on genetic impairment of myeloid cell recruitment, neutralisation of the XCR1-ligand XCL1 or depletion of CD8+ T cells. Therapeutic benefit was accompanied by an unexpected increase in tumour-associated neutrophils (TANs) which switched from a protumour to anti-tumour progenitor-like neutrophil phenotype. Reprogrammed TANs were found in direct contact with CD8+ T cells in clusters that were enriched for the cytotoxic anti-tumoural protease granzyme B. Neutrophil reprogramming was not observed in the circulation indicative of the combination therapy selectively influencing TANs. CONCLUSION: CXCR2-inhibition induces reprogramming of the tumour immune microenvironment that promotes ICI in NASH-HCC.

Bittersweet: infective complications of drug-induced glycosuria in patients with diabetes mellitus on SGLT2-inhibitors: two case reports.

BACKGROUND: Sodium-glucose co-transporter 2 (SGLT2) inhibitors are novel hypoglycemic agents which reduce reabsorption of glucose at the renal proximal tubule, resulting in significant glycosuria and increased risk of genital mycotic infections (GMI). These infections are typically not severe as reported in large systematic reviews and meta-analyses of the medications. These reviews have also demonstrated significant cardiovascular benefits through other mechanisms of action, making them attractive options for the management of Type 2 diabetes mellitus (T2DM). We present two cases with underlying abnormalities of the urogenital tract in which the GMI were complicated and necessitated cessation of the SGLT2 inhibitor. CASE PRESENTATIONS: Both cases are patients with T2DM on empagliflozin, an SGLT2 inhibitor. The first case is a 64 year old man with Candida albicans balanitis and candidemia who was found to have an obstructing renal calculus and prostatic abscess requiring operative management. The second case describes a 72 year old man with Candida glabrata candidemia who was found to have prostatomegaly, balanitis xerotica obliterans with significant urethral stricture and bladder diverticulae. His treatment was more complex due to fluconazole resistance and concerns about urinary tract penetration of other antifungals. Both patients recovered following prolonged courses of antifungal therapy and in both cases the SGLT2 inhibitor was ceased. CONCLUSIONS: Despite their cardiovascular benefits, SGLT2 inhibitors can be associated with complicated fungal infections including candidemia and patients with anatomical abnormalities of the urogenital tract may be more susceptible to these infections as demonstrated in these cases. Clinicians should be aware of their mechanism of action and associated risk of infection and prior to prescription, assessment of urogenital anatomical abnormalities should be performed to identify patients who may be at risk of complicated infection.

Associations Among Plant-Based Diet Quality, Uremic Toxins, and Gut Microbiota Profile in Adults Undergoing Hemodialysis Therapy.

OBJECTIVE: The objective of the study was to evaluate associations among diet quality, serum uremic toxin concentrations, and the gut microbiota profile in adults undergoing hemodialysis therapy. DESIGN AND METHODS: This is a cross-sectional analysis of baseline data from a clinical trial involving adults receiving hemodialysis therapy. Usual dietary intake was determined using a diet history method administered by Accredited Practising Dietitians. Two approaches were used for diet quality assessment: (1) using three a priori defined plant-based diet indices-an overall plant-based diet index (PDI), a healthy PDI, and an unhealthy PDI and (2) classification of food group intake. Serum uremic toxins (p-cresyl sulfate and indoxyl sulfate (IS); free and total) were determined by ultra-performance liquid chromatography. Gut microbiota composition was established through sequencing the 16S rRNA gene in stool samples. RESULTS: Twenty-two adults (median age 70.5 [interquartile range: 59-76], 64% male) were included in the final analysis. Higher adherence to the PDI was associated with lower total IS levels (P = .028), independent of dialysis adequacy, urinary output, and blood albumin levels. In contrast, higher adherence to the unhealthy PDI was associated with increases in both free and total IS. Several other direct and inverse associations between diet quality with uremic toxins, microbial relative abundances, and diversity metrics were also highlighted. Diet-associated taxa showed significantly different trends of association with serum uremic toxin concentrations (P < .05). Higher adherence to the PDI was negatively associated with relative abundances of Haemophilus and Haemophilus parainfluenzae that were related to elevated total IS levels. In contrast, increased intake of food items considered unhealthy, such as animal fats, sweets and desserts, were associated with bacteria linked to higher IS and p-cresyl sulfate (total and free) concentrations. CONCLUSIONS: The quality of diet and food selections may influence uremic toxin production by the gut microbiota in adults receiving hemodialysis. Well-designed dietary intervention trials that adopt multi-omic technologies appropriate for the functional annotation of the gut microbiome are needed to validate our findings and establish causality.

Orthognathic Surgery of the Mandible.

Orthognathic surgery performed in conjunction with orthodontic treatment is commonly performed to correct skeletal irregularities and realign the maxillomandibular relationship to improve occlusal function and facial esthetics. A thorough understanding of soft tissue esthetics, skeletal and occlusal relationships, and surgical techniques is required to obtain successful results. Surgical techniques have evolved greatly throughout history, as technological advances such as virtual surgical planning have become available and widely used to obtain predictable movements with minimized complications. The aim of this article is to review the orthognathic surgical procedures of the mandible, with particular attention to the indications, contraindications, preoperative assessment, surgical technique, and possible complications encountered.

Multiple Immunostainings with Different Epitope Retrievals-The FOLGAS Protocol.

We describe a sequential multistaining protocol for immunohistochemistry, immunofluorescence and CyTOF imaging for formalin-fixed, paraffin-embedded specimens (FFPE) in the formalin gas-phase (FOLGAS), enabling sequential multistaining, independent from the primary and secondary antibodies and retrieval. Histomorphologic details are preserved, and crossreactivity and loss of signal intensity are not detectable. Combined with a DAB-based hydrophobic masking of metal-labeled primary antibodies, FOLGAS allows the extended use of CyTOF imaging in FFPE sections.

Classification of Human White Blood Cells Using Machine Learning for Stain-Free Imaging Flow Cytometry.

Imaging flow cytometry (IFC) produces up to 12 spectrally distinct, information-rich images of single cells at a throughput of 5,000 cells per second. Yet often, cell populations are still studied using manual gating, a technique that has several drawbacks, hence it would be advantageous to replace manual gating with an automated process. Ideally, this automated process would be based on stain-free measurements, as the currently used staining techniques are expensive and potentially confounding. These stain-free measurements originate from the brightfield and darkfield image channels, which capture transmitted and scattered light, respectively. To realize this automated, stain-free approach, advanced machine learning (ML) methods are required. Previous works have successfully tested this approach on cell cycle phase classification with both a classical ML approach based on manually engineered features, and a deep learning (DL) approach. In this work, we compare both approaches extensively on the problem of white blood cell classification. Four human whole blood samples were assayed on an ImageStream-X MK II imaging flow cytometer. Two samples were stained for the identification of eight white blood cell types, while two other sample sets were stained for the identification of resting and active eosinophils. For both data sets, four ML classifiers were evaluated on stain-free imagery with stratified 5-fold cross-validation. On the white blood cell data set, the best obtained results were 0.778 and 0.703 balanced accuracy for classical ML and DL, respectively. On the eosinophil data set, this was 0.871 and 0.856 balanced accuracy. We conclude that classifying cell types based on only stain-free images is possible with all four classifiers. Noteworthy, we also find that the DL approaches tested in this work do not outperform the approaches based on manually engineered features. © 2019 International Society for Advancement of Cytometry.

Does urethral length affect continence outcomes following robot assisted laparoscopic radical prostatectomy (RALP)?

BACKGROUND: Post-operative urinary incontinence is a significant concern for patients choosing to undergo a radical prostatectomy (RP) for treatment of prostate cancer. The aim of our study was to determine the effect of pre-operative MUL on 12 month continence outcomes in men having robot-assisted laparoscopic prostatectomy (RALP). METHODS: We use the South Australian Prostate Cancer Clinical Outcomes Collaborative (SA-PCCOC) database, to identify 602 patients who had undergone RALP by a high volume surgeon. Only patients who received an assessment and education by a specialist pelvic floor physiotherapist, had completed EPIC questionnaires before treatment and did not have radiotherapy treatment within 12 months of surgery were included. MUL measurements were taken from pre-operative magnetic resonance imaging (MRI) scans. The short-form version of the Expanded Prostate Cancer Index Composite (EPIC-26) was used to measure continence outcomes. Continence was defined as 100/100 in the EPIC-26 Urinary Continence domain score. RESULTS: The observed median MUL in this study was 14.6 mm. There was no association between MUL and baseline continence. MUL was associated with continence at 12 months post RALP (OR 1.13, 95% CI 1.03-1.21, p = 0.0098). In men who were continent before surgery, MUL was associated with return to continence at 12 months after RALP (OR 1.15, 1.05-1.28, p = 0.006). MUL was also associated with change in continence after surgery (ß = 1.22, p = 0.002). CONCLUSIONS: MUL had no effect on baseline continence but had a positive and significant association with continence outcomes over 12 months post RALP.

Safety and Efficacy of Using Nuts to Improve Bowel Health in Hemodialysis Patients.

OBJECTIVE: Constipation is common in patients with end-stage kidney disease. Nondrug strategies to manage constipation are challenging because of dietary potassium, phosphate, and fluid restrictions. Nuts are a high-fiber food but are excluded from the diet because of the high potassium and phosphate content. The aim of this study was to examine the safety and efficacy of using nuts to improve constipation in adults undertaking hemodialysis (HD). DESIGN AND METHODS: Adult patients undertaking HD were recruited to this nonrandomized, 10-week repeated measures, within-subject, pragmatic clinical trial, conducted in two HD units. The intervention consisted of consumption of 40g of raw almonds daily for four weeks, followed by a two-week washout and four-week control period. The primary safety outcome measures were change in predialysis serum potassium and phosphate levels. The primary efficacy outcome was reduction in constipation, measured using the Bristol Stool Form Scale and Palliative Care Outcome Scale (POS-S) renal symptom score. Secondary outcomes included quality of life, selected uremic toxins, cognition, gut microbiota profile, and symptom burden. RESULTS: Twenty patients completed the trial (median age: 67 [interquartile range: 57.5-77.8] years, 51% male). After controlling for dialysis adequacy, anuria, dietary intake, bicarbonate, and parathyroid hormone, there were no statistically significant changes in serum potassium (P = 0.21) or phosphate (P = 0.16) associated with daily consumption of almonds. However, statistically significant improvements in constipation were seen at weeks 2, 3, 4, and 10. There were statistically significant improvements in quality of life (P = 0.030), overall symptom burden (P = 0.002), vomiting (P = 0.020), itching (P = 0.006), and skin changes (P = 0.002). CONCLUSION: Daily consumption of almonds for four weeks was safe, effective, and well tolerated. Improvements in quality of life and symptom burden warrant further research to elucidate potential mechanisms. The findings support the potential reinclusion of foods such as nuts into the diet of patients who underwent HD.

The Use of Allogeneic Cartilage for Grafting in Functional and Reconstructive Rhinoplasty.

PURPOSE: Allogeneic cartilage grafting has multiple uses in rhinoplasty. Autogenous cartilage is frequently used in cases of nasal obstruction or reconstruction, but harvesting grafts can cause complications or might be contraindicated. Rhinoplasties on the patient with a cleft might require costochondral grafts. Allogeneic rib is an effective and safe alternative to autogenous grafts, prevents complications, and obviates postoperative admission after rib harvest. MATERIALS AND METHODS: Patients who had allogeneic cartilage placed during functional or reconstructive rhinoplasty were studied from 2 institutions, including 19 who had functional rhinoplasty using allogeneic Cartiform patellar cartilage grafts and 15 patients who underwent reconstructive cleft rhinoplasty with allogeneic rib cartilage. Postoperative follow-up was at least 6 months, and graft handling characteristics and improvement in breathing were assessed. Internal and external nasal valve (INV and ENV, respectively) patencies were evaluated in patients who received the Cartiform grafts, and cosmetic outcomes were rated for patients with reconstructed clefts. RESULTS: The average age of patients who underwent functional rhinoplasty was 57.3 years, and all were men with compromised nasal breathing. Cartiform cartilage was used to repair INV or ENV collapse. Postoperatively, all patients had patent INVs and ENVs and reported improved nasal breathing. Patients who received the rib allograft had an average age of 18 years and 40% were male; all had severe nasal deformities secondary to cleft or craniofacial conditions. Patients rated their preoperative nasal breathing as 4 of 10 on average and cosmetic appearance as 3 of 10; postoperatively, these were rated as 9 of 10. Complications were not noted, except for 1 superficial infection (unrelated to the graft) and 1 hypertrophic scar. There were no postoperative admissions. The mechanical and handling properties of the Cartiform and allogeneic rib were appropriate. CONCLUSION: Allogeneic cartilage is an acceptable alternative to autologous cartilage in functional and reconstructive rhinoplasty.

Treatment selection for urolithiasis: percutaneous nephrolithomy, ureteroscopy, shock wave lithotripsy, and active monitoring.

Urolithiasis is a significant worldwide source of morbidity, constituting a common urological disease that affects between 10 and 15% of the world population. Recent technological and surgical advances have replaced the need for open surgery with less invasive procedures. The factors which determine the indications for percutaneous nephrolithotomy include stone factors (stone size, stone composition, and stone location), patient factors (habitus and renal anomalies), and failure of other treatment modalities (ESWL and flexible ureteroscopy). The accepted indications for PCNL are stones larger than 20 mm2, staghorn and partial staghorn calculi, and stones in patients with chronic kidney disease. The contraindications for PCNL include pregnancy, bleeding disorders, and uncontrolled urinary tract infections. Flexible ureteroscopy can be one of the options for lower pole stones between 1.5 and 2 cm in size. This option should be exercised in cases of difficult lower polar anatomy and ESWL-resistant stones. Flexible ureteroscopy can also be an option for stones located in the diverticular neck or a diverticulum. ESWL is the treatment to be discussed as a option in all patient with renal stones (excluding lower polar stones) between size 10 and 20 mm. In addition, in lower polar stones of size between 10 and 20 mm if the anatomy is favourable, ESWL is the option. In proximal ureteral stones, ESWL should be considered as a option with flexible ureteroscopy Active monitoring has a limited role and can be employed in post-intervention (PCNL or ESWL) residual stones, in addition, asymptomatic patients with no evidence of infection and fragments less than 4 mm can be monitored actively.

Defining a safe player run-off zone around rugby union playing areas.

OBJECTIVES: To identify the circumstances in which international rugby players exit the playing area during match activities and to define a safe run-off distance around the playing area. METHOD: An observational study using video recordings of 102 matches associated with the Rugby World Cup (2011), Rugby Championship (2013, 2014) and Six Nations Championship (2013, 2014) were used to analyse every event in which one or more players exited the playing area during normal match activities. The circumstances in which a player exited the playing area were categorised using a range of parameters: playing position, location, out-of-play region, match activity, distance travelled over the touchline, contacts made with pitchside fixtures and fittings. RESULTS: Ninety-five per cent of player-excursions took place within 5.2 m of the touchline. Players exiting the playing area were nearly three times more likely to be a back than a forward (p<0.001) and the event was more likely to take place when a team was defending than attacking (p<0.001). Being forced out of play during a contact event (70%) was the major reason for players exiting the playing area. Most players (88%) exiting the playing area only made contact with the perimeter area surface; a small proportion of players contacted touchline flags (6.1%), advertising boards (2.3%) and TV cameras/equipment (1.0%). CONCLUSIONS: A minimum hazard-free distance of 5 m around a Rugby pitch is proposed based on the 95% percentile frequency distribution of player-excursion events into the areas contiguous with the playing area.

Should we routinely stent after ureteropyeloscopy?

Arguments 'for' and 'against' ureteric stenting after ureteropyeloscopy are discussed. An individualised approach balancing renal function preservation, irritative lower urinary tract symptoms and emergent return to theatre needs to be adopted while being mindful of healthcare spending.

Systematic review of the ophthalmic complications of robotic-assisted laparoscopic prostatectomy.

This study aims to review ophthalmic injuries sustained during of robotic-assisted laparoscopic prostatectomy (RALP). A search of Medline, Embase, Cochrane and grey literature was performed using methods registered a priori. Eligible studies were published 01/01/2010-01/05/2023 in English and reported ophthalmic complications in cohorts of > 100 men undergoing RALP. The primary outcome was injury incidence. Secondary outcomes were type and permanency of ophthalmic complications, treatments, risk factors and preventative measures. Nine eligible studies were identified, representing 100,872 men. Six studies reported rates of corneal abrasion and were adequately homogenous for meta-analysis, with a weighted pooled rate of 5 injuries per 1000 procedures (95% confidence interval 3-7). Three studies each reported different outcomes of xerophthalmia, retinal vascular occlusion, and ophthalmic complications unspecified in 8, 5 and 2 men per 1000 procedures respectively. Amongst identified studies, there were no reports of permanent ophthalmic complications. Injury management was poorly reported. No significant risk factors were reported, while one study found African-American ethnicity protective against corneal abrasion (0.4 vs. 3.9 per 1000). Variables proposed (but not proven) to increase risk for corneal abrasion included steep Trendelenburg position, high pneumoperitoneum pressure, prolonged operative time and surgical inexperience. Compared with standard of care, occlusive eyelid dressings (23 vs. 0 per 1000) and foam goggles (20 vs. 1.3 per 1000) were found to reduce rates of corneal abrasion. RALP carries low rates of ophthalmic injury. Urologists should counsel the patient regarding this potential complication and pro-actively implement preventative strategies.

A stagewise response to mitochondrial dysfunction in mitochondrial DNA maintenance disorders.

Mitochondrial DNA (mtDNA) deletions which clonally expand in skeletal muscle of patients with mtDNA maintenance disorders, impair mitochondrial oxidative phosphorylation dysfunction. Previously we have shown that these mtDNA deletions arise and accumulate in perinuclear mitochondria causing localised mitochondrial dysfunction before spreading through the muscle fibre. We believe that mito-nuclear signalling is a key contributor in the accumulation and spread of mtDNA deletions, and that knowledge of how muscle fibres respond to mitochondrial dysfunction is key to our understanding of disease mechanisms. To understand the contribution of mito-nuclear signalling to the spread of mitochondrial dysfunction, we use imaging mass cytometry. We characterise the levels of mitochondrial Oxidative Phosphorylation proteins alongside a mitochondrial mass marker, in a cohort of patients with mtDNA maintenance disorders. Our expanded panel included protein markers of key signalling pathways, allowing us to investigate cellular responses to different combinations of oxidative phosphorylation dysfunction and ragged red fibres. We find combined Complex I and IV deficiency to be most common. Interestingly, in fibres deficient for one or more complexes, the remaining complexes are often upregulated beyond the increase of mitochondrial mass typically observed in ragged red fibres. We further find that oxidative phosphorylation deficient fibres exhibit an increase in the abundance of proteins involved in proteostasis, e.g. HSP60 and LONP1, and regulation of mitochondrial metabolism (including oxidative phosphorylation and proteolysis, e.g. PHB1). Our analysis suggests that the cellular response to mitochondrial dysfunction changes depending on the combination of deficient oxidative phosphorylation complexes in each fibre.