Impact of changing from autopsy to post-mortem CT in an entire HM Coroner region due to a shortage of available pathologists

A significant problem facing routine medicolegal coroner-referred autopsies is a shortfall of pathologists prepared to perform them. This was particularly acute in Lancashire, where the coroner decided to initiate a service that relied on post-mortem computed tomography (PMCT). This involved training anatomical pathology technologists (APTs) to perform external examinations, radiographers to perform scans, and radiologists to interpret them. The service started in 2018 and now examines over 1,500 cases per year. This study outlines the PMCT process using NHS staff, with CT equipment and logistics managed by the commercial sector. It compares the demographics and outcomes of PM investigations for two 6-month periods: the autopsy service prior to 2018, and then the PMCT service. These data were then compared with previous UK PMCT data. Referrals for adult non-suspicious deaths were made in 913 cases of which 793 (87%) had PMCT between 01/10/2018 and 31/03/2019. Fifty-six cases had autopsy after PMCT, so 81% of cases potentially avoided autopsy. The PMCT service did not delay release of bodies to the next-of-kin. Comparing the cause of death given shows no difference in the proportions of natural and unnatural deaths. There was an increase in diagnosis of coronary artery disease for PMCT, with less respiratory diagnoses, a feature not previously demonstrated. These data suggest PMCT is a practical solution for potentially failing autopsy services. By necessity, this involves changes in diagnoses, as PMCT and autopsy have different strengths and weakness, but the ability to pick up unnatural death appears unaffected.

Technical success of endoscopic stenting for malignant gastric outlet obstruction

BACKGROUND

Palliation of irresectable malignant gastric outlet obstruction (GOO) using self-expanding metal stents (SEMS) is gaining popularity with high technical success rates. The aim of this study was to review and compare GOO stenting for malignancy with other series.

METHODS

A retrospective review of all patients undergoing pyloroduodenal stenting for malignant GOO at Groote Schuur Hospital, 1 March 2018-31 August 2021, evaluating demographics, technical success, pathology, and stentrelated complications was done.

RESULTS

One hundred and fourteen patients, of which 38.6% were female, were included, with gastric malignancies (74.6%) being the most frequent underlying pathology. Median age was 64 years (IQR 53-70 years), with 48.2% having at least one comorbidity. The majority (96 patients; 85.7%) required only one stent. In total, 132 stent insertion attempts were undertaken. Three technical failures were experienced (one incorrect stent placement and two failed insertions), equating to a 97.4% technical success rate. Four immediate complications occurred (3.1%): two related to sedation, one incorrect stent placement and an oesophagogastric junction perforation with procedural death. Fifteen delayed complications occurred: 13 tumour in-growth blockages, one stent fracture and one case of poor radial stent expansion. Stent blockages occurred at a median of 107 days (IQR 80-275 days). Salvage stenting was 100% successful in 14 cases requiring re-stenting.

CONCLUSION

Technical insertion success rates of primary and salvage duodenal stenting for malignant GOO are on par with international high-volume units. The leading pathology locally is gastric adenocarcinoma, with palliative stenting remaining a feasible and accessible option.

Impact of the COVID-19 pandemic on a post-mortem CT service for adult non-suspicious death

Due to the COVID-19 pandemic, the post-mortem computed tomography (PMCT) service was expanded from three to seven cases per day to help mortuary services and avoid invasive autopsy. Additional targeted angiography and pulmonary ventilation procedures were stopped and triage rules relaxed to allow more indications to be scanned, including those requiring toxicology. A service evaluation was performed for the first 3-months of the COVID-19 pandemic compared to the equivalent period the previous year to study the impact of these changes. It was found that, despite the increase in deaths regionally, coronial referrals remained about 100 per month, a reduction in referral rate. The number undergoing PMCT rose from 28% to 74% of cases. Turnaround time remained the same. For cases triaged to PMCT, the need for subsequent autopsy increased from 7.9% to 15.8%. No significant changes were seen in diagnosis rates, including cardiac or respiratory. There was an increase in patients with coronary death without severe coronary calcification who underwent autopsy after PMCT. These may have been diagnosed by targeted coronary angiography. Fifty-three cases requiring toxicology/biochemistry had PMCT, with 38 having PMCT only. In 8/11 (72.7%) cases with normal PMCT and toxicology as the key diagnostic test, autopsy was performed prior to results. This suggests the pathology team were reluctant to risk an "unascertained" outcome. This study shows that it is possible to increase PMCT services by widening referral criteria and by limiting the use of enhanced imaging techniques, without significantly changing diagnosis rates of key diseases; however, selectively restarting targeted angiography may help avoid autopsy in some cases.

Transgenic Microalgae Expressing Double-Stranded RNA as Potential Feed Supplements for Controlling White Spot Syndrome in Shrimp Aquaculture

Viral infection of farmed fish and shellfish represents a major issue within the aquaculture industry. One potential control strategy involves RNA interference of viral gene expression through the oral delivery of specific double-stranded RNA (dsRNA). In previous work, we have shown that recombinant dsRNA can be produced in the chloroplast of the edible microalga Chlamydomonas reinhardtii and used to control disease in shrimp. Here, we report a significant improvement in antiviral dsRNA production and its use to protect shrimp against white spot syndrome virus (WSSV). A new strategy for dsRNA synthesis was developed that uses two convergent copies of the endogenous rrnS promoter to drive high-level transcription of both strands of the WSSV gene element in the chloroplast. Quantitative RT-PCR indicated that ~119 ng dsRNA was produced per liter of culture of the transgenic microalga. This represents an ~10-fold increase in dsRNA relative to our previous report. The engineered alga was assessed for its ability to prevent WSSV infection when fed to shrimp larvae prior to a challenge with the virus. The survival of shrimp given feed supplemented with dried alga containing the dsRNA was significantly enhanced (~69% survival) relative to a negative control (<10% survival). The findings suggest that this new dsRNA production platform could be employed as a low-cost, low-tech control method for aquaculture.

Yields and product comparison between Escherichia coli BL21 and W3110 in industrially relevant conditions: anti-c-Met scFv as a case study

INTRODUCTION

In the biopharmaceutical industry, Escherichia coli is one of the preferred expression hosts for large-scale production of therapeutic proteins. Although increasing the product yield is important, product quality is a major factor in this industry because greatest productivity does not always correspond with the highest quality of the produced protein. While some post-translational modifications, such as disulphide bonds, are required to achieve the biologically active conformation, others may have a negative impact on the product's activity, effectiveness, and/or safety. Therefore, they are classified as product associated impurities, and they represent a crucial quality parameter for regulatory authorities.

RESULTS

In this study, fermentation conditions of two widely employed industrial E. coli strains, BL21 and W3110 are compared for recombinant protein production of a single-chain variable fragment (scFv) in an industrial setting. We found that the BL21 strain produces more soluble scFv than the W3110 strain, even though W3110 produces more recombinant protein in total. A quality assessment on the scFv recovered from the supernatant was then performed. Unexpectedly, even when our scFv is correctly disulphide bonded and cleaved from its signal peptide in both strains, the protein shows charge heterogeneity with up to seven distinguishable variants on cation exchange chromatography. Biophysical characterization confirmed the presence of altered conformations of the two main charged variants.

CONCLUSIONS

The findings indicated that BL21 is more productive for this specific scFv than W3110. When assessing product quality, a distinctive profile of the protein was found which was independent of the E. coli strain. This suggests that alterations are present in the recovered product although the exact nature of them could not be determined. This similarity between the two strains' generated products also serves as a sign of their interchangeability. This study encourages the development of innovative, fast, and inexpensive techniques for the detection of heterogeneity while also provoking a debate about whether intact mass spectrometry-based analysis of the protein of interest is sufficient to detect heterogeneity in a product.

Glacier retreat reorganizes river habitats leaving refugia for Alpine invertebrate biodiversity poorly protected

Alpine river biodiversity around the world is under threat from glacier retreat driven by rapid warming, yet our ability to predict the future distributions of specialist cold-water species is currently limited. Here we link future glacier projections, hydrological routing methods and species distribution models to quantify the changing influence of glaciers on population distributions of 15 alpine river invertebrate species across the entire European Alps, from 2020 to 2100. Glacial influence on rivers is projected to decrease steadily, with river networks expanding into higher elevations at a rate of 1% per decade. Species are projected to undergo upstream distribution shifts where glaciers persist but become functionally extinct where glaciers disappear completely. Several alpine catchments are predicted to offer climate refugia for cold-water specialists. However, present-day protected area networks provide relatively poor coverage of these future refugia, suggesting that alpine conservation strategies must change to accommodate the future effects of global warming.

Highly efficient export of a disulfide‐bonded protein to the periplasm and medium by the Tat pathway using CyDisCo in Escherichia coli

High‐value heterologous proteins produced in Escherichia coli that contain disulfide bonds are almost invariably targeted to the periplasm via the Sec pathway as it, among other advantages, enables disulfide bond formation and simplifies downstream processing. However, the Sec system cannot transport complex or rapidly folding proteins, as it only transports proteins in an unfolded state. The Tat system also transports proteins to the periplasm, and it has significant potential as an alternative means of recombinant protein production because it transports fully folded proteins. Most of the studies related to Tat secretion have used the well‐studied TorA signal peptide that is Tat‐specific, but this signal peptide also tends to induce degradation of the protein of interest, resulting in lower yields. This makes it difficult to use Tat in the industry. In this study, we show that a model disulfide bond‐containing protein, YebF, can be exported to the periplasm and media at a very high level by the Tat pathway in a manner almost completely dependent on cytoplasmic disulfide formation, by other two putative Tat SPs: those of MdoD and AmiC. In contrast, the TorA SP exports YebF at a low level.

P16.03.A Epithelioid gliobastoma requires rapid treatment and BRAF inhibitors should be made readily available for their treatment

Background

Epithelioid glioblastoma is a rare subtype of Glioblastoma. We examine two cases who presented acutely with symptoms of headache, neck stiffness and an eye squint. The purpose of this case review is to look at their management, the spread of the disease and propose the availability of BRAF inhibiting agents be made readily available for this subtype.

Material and Methods

The clinical records including pathology and surgical reports, multi-disciplinary team meeting documents, oncology plans and inpatient notes have all been reviewed alongside the literature on epithelioid GBM and BRAF V600e mutations and inhibitors.

Results

Patients were females aged 25 and 32 presenting with acute onset headache and neck stiffness to emergency Department. The 25 year old had developed a right eye squint within seven days of the other symptoms, her tumour was right frontal with midline shift. The 32 year old had symptoms for 10 days prior to presentation, the tumour was right temporal. They both underwent craniotomies. The frontal tumour was totally resected, while the temporal lobe tumour was haemorrhagic in nature and minimally de-bulked. Pre-operative stealth imaging showed that there had been an increase in the size of the temporal lesion in the fourteen days since presentation. Histology proved these to be epithelioid GBM’s with BRAF V600e mutations, IDH wild-type and TERT promoter mutant. Full pathology reports with molecular markers were available within ten days. The frontal lobe patient began chemo-radiation sixteen days from her surgical date. On day two she was admitted with severe headache and nausea. She became agitated, confused, and transferred back to the neurosurgery unit for management of hydrocephalus. She was diagnosed with PRES and simultaneously treated for this and hydrocephalus. Clinically she suffered storming, passing away exactly eight weeks from presentation. Seven days after surgery the temporal lobe tumour patient suffered a seizure and admitted for symptom management and expedite oncology treatment. She passed away six days later suffering continual neurological deterioration and the tumour progression with leptomeningeal spread. This was exactly four weeks from initial presentation.

Conclusion

The prognosis for epithelioid Glioblastoma is limited to weeks to short months. Extent of resection in these case studies demonstrates benefit in delaying progression though it is clear that time is of the essence from presentation, to surgery, to adjuvant treatment. Neither of these tumours were methylated meaning the standard treatment for glioblastoma is likely to lack efficacy. BRAF inhibitors should be made readily available for this rare sub-type to commence treatment expediently. Both patients suffered distressing neurological symptoms in their final days which require expert management and are best managed in a neurosurgical centre.

P11.06.A benefits of carbohydrate loading drinks pre-operatively for patients with a presumed high-grade glioma planned for an awake craniotomy

Background

As part of enhanced recovery after surgery in neuro oncology, carbohydrate loading drinks were reviewed to see if there were any benefits in administering this pre operatively, in particularly for patients for awake craniotomy electively. This method is currently used in colorectal and spinal teams within the trust. Carbohydrate loading drinks are clear, and can be consumed up to 2 hours before induction of anaesthesia. Currently reviewed for patients for awake craniotomy with the vision to implement for all patients planned for craniotomy, both asleep and awake. The concept of this drink, is that it helps with post-operative nausea and vomiting , insulin resistance, helps with energy boost which is helpful during awake craniotomies and potentially during their engagement with therapists post operatively and wound healing (Hausel J et al, 2005). This could essentially lead to safer discharge, reduced risk of wound infection and reduced length of stay.

Material and Methods

In a single centre, data for patients who have undergone awake craniotomies this year were abstracted. Patients planned for an awake surgery were prescribed carb-loading drinks. Due to the start date of this study, there were already a number of patients who have had their awake craniotomies without having carb-loading drinks prescribed. The data for both cohorts enabled comparison on engagement during and after awake craniotomies with therapists and length of stay.

Results

The current data collected has found that the average length of stay in the group who were not prescribed carbohydrate loading drinks pre operatively, had an average length of stay 7.2 days in total, 50% had experienced nausea and vomiting post operatively, which led therapists unable to perform assessments. 66% of patients in this group were found to have some form of difficulties engaging with the therapists during the awake phase of their craniotomies. Compared with patients who were prescribed the carbohydrate loading drink, the average length of stay was 4.6 days, with no post operative nausea and vomiting, no difficulties engaging with therapists post operatively.

Conclusion

Though the current data is of a small volume, carbohydrate loading pre-operatively can help patients for elective awake craniotomies and reduce length of stay in hospital, optimising their recovery in a fast yet safe manner to ensure they are in the best performance status prior to commencing oncology treatment. With further analysis into the use of carb-loading drinks pre-operatively, this can be used widely within neuro-oncology surgeries.

Hausel J, Nygren J, Thorell A et al Randomized clinical trial of the effects of oral preoperative carbohydrates on postoperative nausea and vomiting after laparoscopic cholecystectomy. Br J Surg 2005; : 415-421. [PubMed] [Google Scholar]

Evaluation of Methylotrophic Yeast Ogataea thermomethanolica TBRC 656 as a Heterologous Host for Production of an Animal Vaccine Candidate

Multiple yeast strains have been developed into versatile heterologous protein expression platforms. Earlier works showed that Ogataea thermomethanolica TBRC 656 (OT), a thermotolerant methylotrophic yeast, can efficiently produce several industrial enzymes. In this work, we demonstrated the potential of this platform for biopharmaceutical manufacturing. Using a swine vaccine candidate as a model, we showed that OT can be optimized to express and secrete the antigen based on porcine circovirus type 2d capsid protein at a respectable yield. Crucial steps for yield improvement include codon optimization and reduction of OT protease activities. The antigen produced in this system could be purified efficiently and induce robust antibody response in test animals. Improvements in this platform, especially more efficient secretion and reduced extracellular proteases, would extend its potential as a competitive platform for biopharmaceutical industries.

Refolding of lid subdomain of SARS-CoV-2 nsp14 upon nsp10 interaction releases exonuclease activity

During RNA replication, coronaviruses require proofreading to maintain the integrity of their large genomes. Nsp14 associates with viral polymerase complex to excise the mismatched nucleotides. Aside from the exonuclease activity, nsp14 methyltransferase domain mediates cap methylation, facilitating translation initiation and protecting viral RNA from recognition by the innate immune sensors. The nsp14 exonuclease activity is modulated by a protein co-factor nsp10. While the nsp10/nsp14 complex structure is available, the mechanistic basis for nsp10-mediated modulation remains unclear in the absence of the nsp14 structure. Here, we provide a crystal structure of nsp14 in an apo-form. Comparative analysis of the apo- and nsp10-bound structures explain the modulatory role of the co-factor protein and reveal the allosteric nsp14 control mechanism essential for drug discovery. Further, the flexibility of the N-terminal lid of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) nsp14 structure presented in this study rationalizes the recently proposed idea of nsp14/nsp10/nsp16 ternary complex.

Hospital re-admission after critical care survival: a systematic review and meta-analysis

Survivors of critical illness frequently require increased healthcare resources after hospital discharge. We undertook a systematic review and meta-analysis to assess hospital re-admission rates following critical care admission and to explore potential re-admission risk factors. We searched the MEDLINE, Embase and CINAHL databases on 05 March 2020. Our search strategy incorporated controlled vocabulary and text words for hospital re-admission and critical illness, limited to the English language. Two reviewers independently applied eligibility criteria and assessed quality using the Newcastle Ottawa Score checklist and extracted data. The primary outcome was acute hospital re-admission in the year after critical care discharge. Of the 8851 studies screened, 87 met inclusion criteria and 41 were used within the meta-analysis. The analysis incorporated data from 3,897,597 patients and 741,664 re-admission episodes. Pooled estimates for hospital re-admission after critical illness were 16.9% (95%CI: 13.3-21.2%) at 30 days; 31.0% (95%CI: 24.3-38.6%) at 90 days; 29.6% (95%CI: 24.5-35.2%) at six months; and 53.3% (95%CI: 44.4-62.0%) at 12 months. Significant heterogeneity was observed across included studies. Three risk factors were associated with excess acute care rehospitalisation one year after discharge: the presence of comorbidities; events during initial hospitalisation (e.g. the presence of delirium and duration of mechanical ventilation); and subsequent infection after hospital discharge. Hospital re-admission is common in survivors of critical illness. Careful attention to the management of pre-existing comorbidities during transitions of care may help reduce healthcare utilisation after critical care discharge. Future research should determine if targeted interventions for at-risk critical care survivors can reduce the risk of subsequent rehospitalisation.

Inexpensive protein overexpression driven by the NarL transcription activator protein

Most Escherichia coli overexpression vectors used for recombinant protein production (RPP) depend on organic inducers, for example, sugars or simple conjugates. However, these can be expensive and, sometimes, chemically unstable. To simplify this and to cut the cost of RPP, we have developed vectors controlled by the Escherichia coli nitrate‐responsive NarL transcription activator protein, which use nitrate, a cheap, stable, and abundant inorganic ion, to induce high‐level controlled RPP. We show that target proteins, such as green fluorescent protein, human growth hormone, and single‐chain variable region antibody fragments can be expressed to high levels using our promoter systems. As nitrate levels are high in many commercial fertilizers, we demonstrate that controlled RPP can be achieved using readily available and inexpensive garden products.

Synthesis, Structure–Activity Relationships, and Antiviral Profiling of 1-Heteroaryl-2-Alkoxyphenyl Analogs As Inhibitors of SARS-CoV-2 Replication

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of COVID-19, has led to a pandemic, that continues to be a huge public health burden. Despite the availability of vaccines, there is still a need for small-molecule antiviral drugs. In an effort to identify novel and drug-like hit matter that can be used for subsequent hit-to-lead optimization campaigns, we conducted a high-throughput screening of a 160 K compound library against SARS-CoV-2, yielding a 1-heteroaryl-2-alkoxyphenyl analog as a promising hit. Antiviral profiling revealed this compound was active against various beta-coronaviruses and preliminary mode-of-action experiments demonstrated that it interfered with viral entry. A systematic structure–activity relationship (SAR) study demonstrated that a 3- or 4-pyridyl moiety on the oxadiazole moiety is optimal, whereas the oxadiazole can be replaced by various other heteroaromatic cycles. In addition, the alkoxy group tolerates some structural diversity.

Epigenetics of Neurotrauma

Epigenetic changes have been linked to a host of disease states. Besides the physiological function of epigenetic changes in regulating cellular function, recent data indicates that key changes in epigenetic activity also play an important pathophysiologic role following neurotrauma specifically. Such manifestations occur through the activation or silencing of different genes. Histone methylation has emerged as a critical component of this process and can be selectively modulated after injury. Pre-clinical studies have resulted in key discoveries regarding specific methylation sites of interest. This focused review highlights some of these early findings and their relationship to clinical outcomes. These findings suggest areas of future investigation and discovery in the quest to develop ideal biomarkers and methods to utilize them in developing therapeutic interventions.

Universal preprocedural SARS-CoV-2 testing protocol within a large healthcare system

This research letter details the safety of a universal asymptomatic preprocedural SARS-CoV-2 testing protocol implemented within a large, integrated healthcare system. Among over 145 000 tests administered, fewer than 1 in 1000 patients had subsequent positive tests within 10 days of an initial negative SARS-CoV-2 test. Despite the infrequency of positive tests after negative screening tests, patient-to-provider transmission was documented in five instances.

Clinical academic radiographers - A challenging but rewarding career

OBJECTIVES

To explain what a clinical academic career can be, what it can lead to for the individual, profession and most importantly the patient, and why these roles are so important to radiography.

KEY FINDINGS

Multiple challenges to the adoption of clinical academic careers exist, including achievable measurable outcomes, visibility & senior support, and balancing different time demands. Equally the rewards are wide ranging and can advance both the individual and profession through role extension opportunities, increased career progression, patient benefits, and academic and research skills.

CONCLUSION

Clinical academic careers can provide advantages for the individual, department, profession and most importantly the patient with advanced clinical practice through evidenced based research.

IMPLICATIONS FOR PRACTICE

Improving clinical academic careers within Radiography will promote research participation and increase radiographic roles in patient-centred research delivery and development. Combining evidenced based research with academic skills will lead to improved patient care and better clinical outcomes.

Novel homozygous variant in BMP1 associated with a rare osteogenesis imperfecta phenotype

Osteogenesis imperfecta (OI) is characterized by bone fragility and increased fracture susceptibility. BMP1 variants have been reported in the rare OI type XIII, specifically referred to herein as BMP1-associated autosomal recessive (AR) OI. We report the clinical presentation and diagnostic evaluation of a patient found to have a novel homozygous variant in BMP1. We also provide an overview of reported BMP1 variants to date, with discussion focusing on the use of bisphosphonate therapy in these patients. A 7-year-old male with speech and motor delay sustained five bilateral tibial fractures with minimal trauma since age 2.5 years. At age 6, he developed severe back pain after a fall. Diffuse spinal osteopenia and multiple vertebral compression fractures (VCF) at T9, L1, L3, and L5 were identified. Total hip BMD was generous (adjusted Z-score* = 1.76), and femoral neck BMD was high (adjusted Z-score* = 2.67). VCFs precluded assessment of lumbar spine BMD. Genetic analysis identified a homozygous missense variant in exon 4 of BMP1 (c.C505T; p.Arg169Cys). Unlike most forms of OI, patients with BMP1-associated AR OI may have normal or paradoxically increased BMD, making BMD and fracture risk correlation difficult. While bisphosphonates (BP) may help reduce recurrent fractures and provide symptomatic relief, the broad phenotypic spectrum and underlying bone pathology, often in the setting of increased BMD, complicate management. HR-pQCT assessment of bone microarchitecture and quality may aid in the decision of BP therapy and subsequent monitoring. Evidence is limited with respect to the effectiveness of BP in this rare form of OI. *Z-score was adjusted for height Z-score.

Clinical Characteristics and Outcomes in Patients with COVID-19 and Cancer: a Systematic Review and Meta-analysis

Much of routine cancer care has been disrupted due to the perceived susceptibility to SARS-CoV-2 infection in cancer patients. Here, we systematically review the current evidence base pertaining to the prevalence, presentation and outcome of COVID-19 in cancer patients, in order to inform policy and practice going forwards. A keyword-structured systematic search was conducted on Pubmed, Cochrane, Embase and MedRxiv databases for studies reporting primary data on COVID-19 in cancer patients. Studies were critically appraised using the NIH National Heart, Lung and Blood Institute's quality assessment tool set. The pooled prevalence of cancer as a co-morbidity in patients with COVID-19 and pooled in-hospital mortality risk of COVID-19 in cancer patients were derived by random-effects meta-analyses. In total, 110 studies from 10 countries were included. The pooled prevalence of cancer as a co-morbidity in hospitalised patients with COVID-19 was 2.6% (95% confidence interval 1.8%, 3.5%, I2: 92.0%). Specifically, 1.7% (95% confidence interval 1.3%, 2.3%, I2: 57.6.%) in China and 5.6% (95% confidence interval 4.5%, 6.7%, I2: 82.3%) in Western countries. Patients most commonly presented with non-specific symptoms of fever, dyspnoea and chest tightness in addition to decreased arterial oxygen saturation, ground glass opacities on computer tomography and non-specific changes in inflammatory markers. The pooled in-hospital mortality risk among patients with COVID-19 and cancer was 14.1% (95% confidence interval 9.1%, 19.8%, I2: 52.3%). We identified impeding questions that need to be answered to provide the foundation for an iterative review of the developing evidence base, and inform policy and practice going forwards. Analyses of the available data corroborate an unfavourable outcome of hospitalised patients with COVID-19 and cancer. Our findings encourage future studies to report detailed social, demographic and clinical characteristics of cancer patients, including performance status, primary cancer type and stage, as well as a history of anti-cancer therapeutic interventions.

A Chemical Probe for the Methyl Transferase PRMT5 with a Novel Binding Mode

Protein arginine methyltransferase 5 (PRMT5) is an enzyme that can symmetrically dimethylate arginine residues in histones and nonhistone proteins by using S-adenosyl methionine (SAM) as the methyl donating cofactor. We have designed a library of SAM analogues and discovered potent, cell-active, and selective spiro diamines as inhibitors of the enzymatic function of PRMT5. Crystallographic studies confirmed a very interesting binding mode, involving protein flexibility, where both the cofactor pocket and part of substrate binding site are occupied by these inhibitors.

Perioperative intravenous contrast administration and the incidence of acute kidney injury after major gastrointestinal surgery: prospective, multicentre cohort study

BACKGROUND

This study aimed to determine the impact of preoperative exposure to intravenous contrast for CT and the risk of developing postoperative acute kidney injury (AKI) in patients undergoing major gastrointestinal surgery.

METHODS

This prospective, multicentre cohort study included adults undergoing gastrointestinal resection, stoma reversal or liver resection. Both elective and emergency procedures were included. Preoperative exposure to intravenous contrast was defined as exposure to contrast administered for the purposes of CT up to 7 days before surgery. The primary endpoint was the rate of AKI within 7 days. Propensity score-matched models were adjusted for patient, disease and operative variables. In a sensitivity analysis, a propensity score-matched model explored the association between preoperative exposure to contrast and AKI in the first 48 h after surgery.

RESULTS

A total of 5378 patients were included across 173 centres. Overall, 1249 patients (23·2 per cent) received intravenous contrast. The overall rate of AKI within 7 days of surgery was 13·4 per cent (718 of 5378). In the propensity score-matched model, preoperative exposure to contrast was not associated with AKI within 7 days (odds ratio (OR) 0·95, 95 per cent c.i. 0·73 to 1·21; P = 0·669). The sensitivity analysis showed no association between preoperative contrast administration and AKI within 48 h after operation (OR 1·09, 0·84 to 1·41; P = 0·498).

CONCLUSION

There was no association between preoperative intravenous contrast administered for CT up to 7 days before surgery and postoperative AKI. Risk of contrast-induced nephropathy should not be used as a reason to avoid contrast-enhanced CT.

Transport of Folded Proteins by the Tat System

The twin-arginine protein translocation (Tat) system has been characterized in bacteria, archaea and the chloroplast thylakoidal membrane. This system is distinct from other protein transport systems with respect to two key features. Firstly, it accepts cargo proteins with an N-terminal signal peptide that carries the canonical twin-arginine motif, which is essential for transport. Second, the Tat system only accepts and translocates fully folded cargo proteins across the respective membrane. Here, we review the core essential features of folded protein transport via the bacterial Tat system, using the three-component TatABC system of Escherichia coli and the two-component TatAC systems of Bacillus subtilis as the main examples. In particular, we address features of twin-arginine signal peptides, the essential Tat components and how they assemble into different complexes, mechanistic features and energetics of Tat-dependent protein translocation, cytoplasmic chaperoning of Tat cargo proteins, and the remarkable proofreading capabilities of the Tat system. In doing so, we present the current state of our understanding of Tat-dependent protein translocation across biological membranes, which may serve as a lead for future investigations.

Determination of Glyphosate and Aminomethylphosphonic Acid in Crops by Capillary Gas Chromatography with Mass-Selective Detection: Collaborative Study

A collaborative study was conducted to validate a method for the determination of glyphosate and aminomethylphosphonic acid (AMPA) in crops. The analytes are extracted from crops with water, and the crude extracts are then subjected to a cation exchange cleanup. The analytes are derivatized by the direct addition of the aqueous extract into a mixture of heptafluorobutanol and trifluoroacetic anhydride. The derivatized analytes are quantitated by capillary gas chromatography with mass-selective detection (MSD). The collaborative study involved 13 laboratories located in 5 countries 12 laboratories returned valid data sets. The crops tested were field corn grain, soya forage, and walnut nutmeat at concentrations of 0.050, 0.40, and 2.0 mg/kg. The study used a split-level pair replication scheme with blindly coded laboratory samples. Twelve materials were analyzed, including 1 control and 3 split-level pairs for each matrix, 1 pair at each nominal concentration. For glyphosate, the mean recovery was 91%, the average intralaboratory variance, the repeatability relative standard deviation (RSDr), was 11%, and the interlaboratory variance, the reproducibility relative standard deviation (RSDR), was 16%. For AMPA, the mean recovery was 87%, the RSDr was 16%, and the RSDR was 25% at mg/kg levels.

Post-mortem CT: is coronary angiography required in the presence of a high coronary artery calcium score?

AIM

To test whether a high coronary artery score predicts that the subsequent post-mortem computed tomography (PMCT) with angiography (PMCTA) will diagnose significant coronary artery disease (CAD); to test the diagnostic impact of assuming there is significant CAD based on a high coronary artery calcium (CAC) score alone; and (3) to test whether the clinical CAC score threshold (400) is the most accurate to make this prediction.

MATERIALS AND METHODS

CAC scoring and PMCTA were performed in cases of adult sudden natural death. Angiography was reviewed to determine if there was sufficient CAD to give as the cause of death. Data were analysed to test whether high calcium score predicts significant CAD.

RESULTS

PMCTA with CAC score was successful in 100/104 PMCT examinations and in 87/100 angiography examinations (87%). Forty-six cases (46%) had a CAC score of >400, the clinical level of severe disease. CAD was given as the cause of death in 31 (67%) of these cases. Angiography was successful in 39 of these cases (84.7%) and showed severe CAD in all but one (97%). Twenty-five (25%) cases were diagnosed with a CAD death without a high CAC score.

CONCLUSION

Although CAC score can neither diagnose nor exclude death due to CAD, the addition of angiography adds little diagnostic information to a high CAC score. If PMCT investigation is to exclude trauma and provide a medical cause of death on the "balance of probabilities", angiography is not required when the calcium score >400. This could reduce the number of patients requiring angiography by almost 50%.

Escherichia coli "TatExpress" strains export several g/L human growth hormone to the periplasm by the Tat pathway

Escherichia coli is a heavily used platform for the production of biotherapeutic and other high‐value proteins, and a favored strategy is to export the protein of interest to the periplasm to simplify downstream processing and facilitate disulfide bond formation. The Sec pathway is the standard means of transporting the target protein but it is unable to transport complex or rapidly folding proteins because the Sec system can only transport proteins in an unfolded state. The Tat system also operates to transport proteins to the periplasm, and it has significant potential as an alternative means of recombinant protein production because it transports fully folded proteins. Here, we have tested the Tat system's full potential for the production of biotherapeutics for the first time using fed‐batch fermentation. We expressed human growth hormone (hGH) with a Tat signal peptide in E. coli W3110 “TatExpress” strains that contain elevated levels of the Tat apparatus. This construct contained four amino acids from TorA at the hGH N‐terminus as well as the initiation methionine from hGH, which is removed in vivo. We show that the protein is efficiently exported to the periplasm during extended fed‐batch fermentation, to the extent that it is by far the most abundant protein in the periplasm. The protein was shown to be homogeneous, disulfide bonded, and active. The bioassay showed that the yields of purified periplasmic hGH are 5.4 g/L culture whereas an enzyme‐linked immunosorbent assay gave a figure of 2.39 g/L. Separate analysis of a TorA signal peptide linked to hGH construct lacking any additional amino acids likewise showed efficient export to the periplasm, although yields were approximately two‐fold lower.

Discovery of a class of highly potent Janus Kinase 1/2 (JAK1/2) inhibitors demonstrating effective cell-based blockade of IL-13 signaling

Disruption of interleukin-13 (IL-13) signaling with large molecule antibody therapies has shown promise in diseases of allergic inflammation. Given that IL-13 recruits several members of the Janus Kinase family (JAK1, JAK2, and TYK2) to its receptor complex, JAK inhibition may offer an alternate small molecule approach to disrupting IL-13 signaling. Herein we demonstrate that JAK1 is likely the isoform most important to IL-13 signaling. Structure-based design was then used to improve the JAK1 potency of a series of previously reported JAK2 inhibitors. The ability to impede IL-13 signaling was thereby significantly improved, with the best compounds exhibiting single digit nM IC₅₀'s in cell-based assays dependent upon IL-13 signaling. Appropriate substitution was further found to influence inhibition of a key off-target, LRRK2. Finally, the most potent compounds were found to be metabolically labile, which makes them ideal scaffolds for further development as topical agents for IL-13 mediated diseases of the lungs and skin (for example asthma and atopic dermatitis, respectively).

Discovery of Soft-Drug Topical Tool Modulators of Sphingosine-1-phosphate Receptor 1 (S1PR1)

In order to study the role of S1PRs in inflammatory skin disease, S1PR modulators are dosed orally and topically in animal models of disease. The topical application of S1PR modulators in these models may, however, lead to systemic drug concentrations, which can complicate interpretation of the observed effects. We set out to design soft drug S1PR modulators as topical tool compounds to overcome this limitation. A fast follower approach starting from the drug ponesimod allowed the rapid development of an active phenolic series of soft drugs. The phenols were, however, chemically unstable. Protecting the phenol as an ester removed the instability and provided a compound that is converted by enzymatic hydrolysis in the skin to the phenolic soft drug species. In simple formulations, topical dosing of these S1PR modulators to mice led to micromolar skin concentrations but no detectable blood concentrations. These topical tools will allow researchers to investigate the role of S1PR in skin, without involvement of systemic S1PR biology.