SERPINA3 is a marker of cartilage differentiation and is essential for the expression of extracellular matrix genes during early chondrogenesis.

Serine proteinase inhibitors (serpins) are a family of structurally similar proteins which regulate many diverse biological processes from blood coagulation to extracellular matrix (ECM) remodelling. Chondrogenesis involves the condensation and differentiation of mesenchymal stem cells (MSCs) into chondrocytes which occurs during early development. Here, and for the first time, we demonstrate that one serpin, SERPINA3 (gene name SERPINA3, protein also known as alpha-1 antichymotrypsin), plays a critical role in chondrogenic differentiation. We observed that SERPINA3 expression was markedly induced at early time points during in vitro chondrogenesis. We examined the expression of SERPINA3 in human cartilage development, identifying significant enrichment of SERPINA3 in developing foetal cartilage compared to total limb, which correlated with well-described markers of cartilage differentiation. When SERPINA3 was silenced using siRNA, cartilage pellets were smaller and contained lower proteoglycan as determined by dimethyl methylene blue assay (DMMB) and safranin-O staining. Consistent with this, RNA sequencing revealed significant downregulation of genes associated with cartilage ECM formation perturbing chondrogenesis. Conversely, SERPINA3 silencing had a negligible effect on the gene expression profile during osteogenesis suggesting the role of SERPINA3 is specific to chondrocyte differentiation. The global effect on cartilage formation led us to investigate the effect of SERPINA3 silencing on the master transcriptional regulator of chondrogenesis, SOX9. Indeed, we observed that SOX9 protein levels were markedly reduced at early time points suggesting a role for SERPINA3 in regulating SOX9 expression and activity. In summary, our data support a non-redundant role for SERPINA3 in enabling chondrogenesis via regulation of SOX9 levels.

UK junior doctors' strikes and patients with cancer: a morally questionable association.

Doctors' strikes are legally permissible in the UK, with the situation differing in other countries. But are they morally permissible? Doug McConnell and Darren Mann have systematically attempted to dismiss the arguments for the moral impermissibility of doctors' strikes and creatively attempted to provide further moral justification for them. Unfortunately for striking doctors, they fail to achieve this. Meanwhile, junior doctors' strikes have continued in the UK through 2023 and have now extended into 2024. In this response, which focuses on the UK situation and specifically junior doctors' strikes in the National Health Service (NHS) in England, I will demonstrate a central problem with their arguments-namely that they underplay the harms caused by prolonged doctors' strikes by ignoring the harms to patients with cancer. This weakens their conclusion that strikes are morally permissible in terms of the conditions and thresholds they set. I then provide a psychological critique of their justification for strikes in terms of the interests of the public. It follows that invoking the controversial concept of supererogatory action is ungrounded but also absurd when you consider time-critical cancer care. If those representing striking doctors wish to maintain a modicum of moral respectability, they should mitigate for patients with cancer and negotiate reasonably and with urgency.

Laparoscopic hernia repair in children: does recreating the open operation improve outcomes? A systematic review.

PURPOSE: The use of laparoscopy for paediatric inguinal hernia repairs has increased significantly over the past 2 decades. However, there is significant variation in the reported recurrence rates in the literature, with many studies reporting higher rates than the open operation. This may be explained by the range of different techniques currently included under the term laparoscopic inguinal hernia repair. The purpose of this study is to determine whether dividing the hernia sac before ligation improves surgical outcomes following a paediatric laparoscopic inguinal hernia repair compared to ligation alone. METHODS: A systematic review of the literature was performed following PRISMA guidelines of all studies reporting the outcomes following paediatric laparoscopic inguinal hernia repair where the technique was recorded as laparoscopic suture ligation alone (LS) or laparoscopic sac division and suture ligation (LSDS). Studies were assessed for risk of bias and exclusion criteria included reported follow-up of less than 6 months. RESULTS: A total of 8518 LS repairs and 6272 LSDS repairs were included in the final analysis. LSDS repair was associated with a significantly lower recurrence rate (odds ratio 0.51, 95% CI 0.36-0.71, p = 0.001). There was no significant difference in the rates of testicular ascent or atrophy. CONCLUSION: Recreating the open operation by hernia sac division followed by suture ligation significantly reduces the risk of hernia recurrence.

An anaesthetist who missed a golden opportunity.

Richard Gordon (1921-2017) was a prolific writer of both humorous fiction and historical reviews. He trained in medicine at St Bartholomew's Hospital (Barts) in London and specialised in anaesthesia working at Hill End Hospital, St Albans (where a large proportion of Barts work took place to avoid the impact of the Blitz during the Second World War) and at the Radcliffe Infirmary, Oxford with Robert Macintosh. He published multiple papers and a book on trichlorethylene anaesthesia and edited a textbook of anaesthesia for medical students which ran for 10 editions. His gift for writing and his prominent public persona placed him in a unique position to highlight the importance of the newly emerging speciality of anaesthesia. He did the exact opposite of this and instead created a representation of an uninterested spectator to surgical activity, a representation which still persists in some quarters today.

Laparoscopic inguinal herniotomy: Recreating the open operation optimises outcomes.

BACKGROUND: Recent evidence suggests simple laparoscopic inguinal herniorrhaphy is associated with higher rates of recurrence and testicular ascent. We instigated a standardised approach to laparoscopic inguinal herniotomy (LIH), with circumferential sac division and 'purse-string' closure (4/0 monofilament polypropylene). An active follow-up programme was pursued. We reviewed our outcomes of this technique and compared them to an open herniotomy (OIH) cohort. METHODS: LIH patients were identified prospectively (2017-2021): OIH retrospectively from 2016. Risk factors for complications were defined: extremely to very preterm (< 32 weeks), emergency presentation with incarceration, and redo surgery for recurrence. Data are presented as median [IQR]. Comparisons used Fisher's exact and Mann-Whitney U tests: significance defined as p < 0.05. RESULTS: 192 inguinal herniae in 140 patients were included in the LIH group and 214 herniae in 179 patients in the OIH group. Groups were similar in age and gender. The LIH group had a significantly larger proportion of cases that were premature, had emergency surgery, or had redo surgery after previous OIH. Follow-up was 24.4 months [10.8-33.6] vs. 66.4 [64.5-68.5] (LIH vs. OIH). Hernia recurrence occurred in 2/192 (1.0%) vs. 4/214 (1.9%) (LIH vs. OIH), p = 0.69. There was one known case of testicular ascent after OIH but none in the LIH group. CONCLUSIONS: Recreation of the open herniotomy laparoscopically appears to confer excellent outcomes, with low rates of recurrence despite a high proportion of patients having known risk factors. Further long-term data on rates of testicular ascent after active follow-up are required.

Matrix metalloproteinase-13 is fully activated by neutrophil elastase and inactivates its serpin inhibitor, alpha-1 antitrypsin: Implications for osteoarthritis.

Matrix metalloproteinase-13 (MMP-13) is a uniquely important collagenase that promotes the irreversible destruction of cartilage collagen in osteoarthritis (OA). Collagenase activation is a key control point for cartilage breakdown to occur, yet our understanding of the proteinases involved in this process is limited. Neutrophil elastase (NE) is a well-described proteoglycan-degrading enzyme which is historically associated with inflammatory arthritis, but more recent evidence suggests a potential role in OA. In this study, we investigated the effect of neutrophil elastase on OA cartilage collagen destruction and collagenase activation. Neutrophil elastase induced significant collagen destruction from human OA cartilage ex vivo, in an MMP-dependent manner. In vitro, neutrophil elastase directly and robustly activated pro-MMP-13, and N-terminal sequencing identified cleavage close to the cysteine switch at 72 MKKPR, ultimately resulting in the fully active form with the neo-N terminus of 85 YNVFP. Mole-per-mole, activation was more potent than by MMP-3, a classical collagenase activator. Elastase was detectable in human OA synovial fluid and OA synovia which displayed histologically graded evidence of synovitis. Bioinformatic analyses demonstrated that, compared with other tissues, control cartilage exhibited remarkably high transcript levels of the major elastase inhibitor, (AAT) alpha-1 antitrypsin (gene name SERPINA1), but these were reduced in OA. AAT was located predominantly in superficial cartilage zones, and staining enhanced in regions of cartilage damage. Finally, active MMP-13 specifically inactivated AAT by removal of the serine proteinase cleavage/inhibition site. Taken together, this study identifies elastase as a novel activator of pro-MMP-13 that has relevance for cartilage collagen destruction in OA patients with synovitis.

Endoscopic vs laparoscopic paediatric gastrostomies: Time to change our practice?

BACKGROUND: Gastrostomy insertion is a common procedure for paediatric surgeons, with the percutaneous endoscopic gastrostomy (PEG) technique long favoured for its simplicity and speed. However, there is growing evidence to suggest that primary laparoscopic balloon gastrostomy (LBG) insertions may have lower complication rates. This study aimed to determine the relative safety and healthcare resource burden of PEG and LBG. METHODS: A retrospective review of all primary gastrostomy insertions (2011-2019). Primary outcome measures included return to theatre for emergency laparotomy and healthcare burden (total gastrostomy-related admissions, length of stay and total theatre utilisation). RESULTS: 338 PEGs and 277 LBGs were inserted with a minimum follow-up period of six months. Following PEG insertion 12/338(3.6%) children required an emergency laparotomy for gastrostomy-related complications. This compared to 2/277(0.7%) following LBG insertion (ARR2.8% (95%CI0.6-5.0), p < 0.0267). When considering all gastrostomy related admissions, there was no significant difference in total theatre utilisation (PEG = 85 [IQR58-117] minutes, LBG = 86 [IQR75-105] minutes, p = 0.12). However, PEGs were found to have an overall longer length of stay 4 [IQR3-7] vs 3 [IQR2-4] days. CONCLUSIONS: LBGs carry a significantly lower rate of major complications and are not associated with an increased healthcare burden. LBG should be considered as the first line method of gastrostomy insertion in children.

Serpins in cartilage and osteoarthritis: what do we know?

Serpins (serine proteinase inhibitors) are an ancient superfamily of structurally similar proteins, the majority of which use an elegant suicide inhibition mechanism to target serine proteinases. Despite likely evolving from a single common ancestor, the 36 human serpins have established roles regulating diverse biological processes, such as blood coagulation, embryonic development and extracellular matrix (ECM) turnover. Genetic mutations in serpin genes underpin a host of monogenic disorders - collectively termed the 'serpinopathies' - but serpin dysregulation has also been shown to drive pathological mechanisms in many common diseases. Osteoarthritis is a degenerative joint disorder, characterised by the progressive destruction of articular cartilage. This breakdown of the cartilage is driven by the metalloproteinases, and it has long been established that an imbalance of metalloproteinases to their inhibitors is of critical importance. More recently, a role for serine proteinases in cartilage destruction is emerging; including the activation of latent matrix metalloproteinases and cell-surface receptors, or direct proteolysis of the ECM. Serpins likely regulate these processes, as well as having roles beyond serine proteinase inhibition. Indeed, serpins are routinely observed to be highly modulated in osteoarthritic tissues and fluids by 'omic analysis, but despite this, they are largely ignored. Confusing nomenclature and an underappreciation for the role of serine proteinases in osteoarthritis (OA) being the likely causes. In this narrative review, serpin structure, biochemistry and nomenclature are introduced, and for the first time, their putative importance in maintaining joint tissues - as well as their dysregulation in OA - are explored.

Clinical Spectrum and Outcomes of Ocular and Periocular Complications following External-Beam Radiotherapy for Inoperable Malignant Maxillary Sinus Tumors.

PURPOSE: To highlight the clinical spectrum, management, and outcomes of ocular/periocular complications following high-dose external-beam radiotherapy (EBRT) for inoperable malignant maxillary sinus-involving tumors (MMST). METHODS: A retrospective, interventional case series. All patients who were diagnosed with inoperable MMST (with orbital involvement) and treated with high-dose fractionated EBRT (65 Gy in 30 fractions) at James Cook University Hospital, UK, were included. RESULTS: Seven patients with advanced MMST (T4aN0M0-T4bN2cM0) were included and were followed up for 23.8 ± 10.2 months. Severe lid margin disease, dry eye, and neurotrophic keratopathy were universally observed. Other complications included cicatricial conjunctivitis (71%), corneal perforation (57%), limbal stem cell deficiency (LSCD; 43%), glaucoma (29%), and superimposed candida keratitis (14%). Amniotic membrane transplant (AMT; 71%), tarsorrhaphy (43%), tectonic keratoplasty (29%), and evisceration (14%) were warranted. Intact corneal epithelium was observed in all patients and good corrected-distance visual acuity (≥20/60) was observed in 3 (43%) patients at final follow-up. CONCLUSION: High-dose EBRT for inoperable MMST can lead to a wide array of severe ocular/periocular complications. AMT serves as a potentially useful treatment modality to restore the ocular surface integrity after severe radiation keratopathy. We advocate active monitoring for any evolving ophthalmic complications during and after EBRT to enable timely intervention.

A non-obstetric exposure to chloroform for Queen Victoria.

The administration of chloroform by John Snow to Queen Victoria to provide analgesia for the delivery of her children was a pivotal moment in the development of anaesthesia. It has long been thought that this was the only occasion she had experienced anaesthesia but examination of her diaries shows this to be untrue.

Collagenolytic matrix metalloproteinases antagonize proteinase-activated receptor-2 activation, providing insights into extracellular matrix turnover.

The collagenase subfamily of matrix metalloproteinases (MMPs) have important roles in the remodeling of collagenous matrices. The proteinase-activated receptor (PAR) family has a unique mechanism of activation requiring proteolysis of an extracellular domain forming a neo-N terminus that acts as a tethered ligand, a process that has been associated with the development of arthritis. Canonical PAR2 activation typically occurs via a serine proteinase at Arg36-Ser37, but other proteinases can cleave PARs downstream of the tethered ligand and "disarm" the receptor. To identify additional cleavage sites within PAR2, we synthesized a 42-amino-acid peptide corresponding to the extracellular region. We observed that all three soluble MMP collagenases, MMP-1, MMP-8, and MMP-13, cleave PAR2 and discovered a novel cleavage site (Ser37-Leu38). Metalloproteinases from resorbing bovine nasal cartilage and recombinant human collagenases could cleave a quenched fluorescent peptide mimicking the canonical PAR2 activation region, and kinetic constants were determined. In PAR2-overexpressing SW1353 chondrocytes, we demonstrated that the activator peptide SLIGKV-NH2 induces rapid calcium flux, inflammatory gene expression (including MMP1 and MMP13), and the phosphorylation of extracellular signal-regulated kinase (ERK) and p38 kinase. The corresponding MMP cleavage-derived peptide (LIGKVD-NH2) exhibited no canonical activation; however, we observed phosphorylation of ERK, providing evidence of biased agonism. Importantly, we demonstrated that preincubation with active MMP-1 reduced downstream PAR2 activation by a canonical activator, matriptase, but not SLIGKV-NH2 These results support a role for collagenases as proteinases capable of disarming PAR2, revealing a mechanism that suppresses PAR2-mediated inflammatory responses.

Recent advances in understanding the regulation of metalloproteinases.

Metalloproteinases remain important players in arthritic disease, in part because members of this large enzymatic family, namely matrix metalloproteinase-1 (MMP-1) and MMP-13, are responsible for the irreversible degradation of articular cartilage collagen. Although direct inhibition of MMPs fell out of vogue with the initial clinical disappointment of the first generation of compounds, interest in other mechanisms that control these important enzymes has always been maintained. Since these enzymes are critically important for tissue homeostasis, their expression and activity are tightly regulated at many levels, not just by direct inhibition by their endogenous inhibitors the tissue inhibitors of metalloproteinases (TIMPs). Focussing on MMP-13, we discuss recent work that highlights new discoveries in the transcriptional regulation of this enzyme, from defined promoter functional analysis to how more global technologies can provide insight into the enzyme's regulation, especially by epigenetic mechanisms, including non-coding RNAs. In terms of protein regulation, we highlight recent findings into enzymatic cascades involved in MMP-13 regulation and activation. Importantly, we highlight a series of recent studies that describe how MMP-13 activity, and in fact that of other metalloproteinases, is in part controlled by receptor-mediated endocytosis. Together, these new discoveries provide a plethora of novel regulatory mechanisms, besides direct inhibition, which with renewed vigour could provide further therapeutic opportunities for regulating the activity of this class of important enzymes.

Surgical management of genitourinary lichen sclerosus et atrophicus in boys in England: A 10-year review of practices and outcomes.

INTRODUCTION: Circumcision has long been the mainstay of management for genitourinary lichen sclerosus et atrophicus (LS); however, there has been growing interest in surgical techniques that preserve the foreskin. OBJECTIVE: The aim of this study was to assess population-based surgical management of LS in England and determine surgical outcomes. STUDY DESIGN: Cases of LS treated in English NHS trusts (2002-2011) were extracted from the Hospital Episode Statistics (HES) Database. Cases were identified by both an ICD-10 code for LS and either an OPCS4.6 code for circumcision or preputioplasty (with/without injection of steroid). Subsequent admissions were analysed for related complications/procedures. Data are presented as median (interquartile range) unless otherwise stated. RESULTS: 7893 patients had surgery for LS, of whom 7567 (95.8%) underwent circumcision (Table). Primary preputioplasty was performed in 326 (4.1%) in 44/130 centres; of these 151/326 had concomitant injection of steroid. Age at surgical intervention was 9 (6-11) years. There were no postoperative bleeds following preputioplasty. Of those treated with preputioplasty, 74 (22%) had subsequent circumcision at a median of 677 (277-1203) days post operation. Concomitant steroid injection reduced the risk of subsequent circumcision (21/151 (14%) vs. 53/175 (30%), p < 0.001). More children underwent a second operative procedure following preputioplasty than those having had a primary circumcision (27.9% vs. 7.9%, p < 0.001). CONCLUSION: Although circumcision is the predominant treatment for LS, these data suggest that preputioplasty is a valid option in management, albeit with a higher re-intervention rate. Selection bias may play a role and a randomized controlled trial is needed. Preputioplasty combined with steroid injection appears to reduce the chance of completion circumcision.

Serine proteinases in the turnover of the cartilage extracellular matrix in the joint: implications for therapeutics.

Cartilage destruction is a key characteristic of arthritic disease, a process now widely established to be mediated by metzincins such as MMPs. Despite showing promise in preclinical trials during the 1990s, MMP inhibitors for the blockade of extracellular matrix turnover in the treatment of cancer and arthritis failed clinically, primarily due to poor selectivity for target MMPs. In recent years, roles for serine proteinases in the proteolytic cascades leading to cartilage destruction have become increasingly apparent, renewing interest in the potential for new therapeutic strategies that utilize pharmacological inhibitors against this class of proteinases. Herein, we describe key serine proteinases with likely importance in arthritic disease and highlight recent advances in this field. LINKED ARTICLES: This article is part of a themed section on Translating the Matrix. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v176.1/issuetoc.

A Forgotten Contribution to Early Anesthesia Literature: The Chloroform Problem: A Textbook Unrepresentative of Contemporary Opinion.

Dr. Richard Gill published a textbook in London in 1906 titled The CHCl3 - Problem. Gill was the Chief Chloroformist at St Bartholomew's Hospital, London, and was recognized as an excellent clinical anesthetist and was of an intelligent but reclusive and eccentric personality. This textbook is rarely found and has not been appreciated in the history of anesthesia for several reasons including that it was generally ignored at publication and few copies exist in libraries around the world. The CHCl3Problem is written in a verbose, archaic, and convoluted fashion and is rarely quoted. It has no references whatsoever. Gill was extensively quoted by one of his students who returned to Australia, Dr. John W Bean, which brought the book to the authors' attention. It was found on the Internet, and a copy from the Boston Medical Library had been scanned and was available as a print-on-demand.