Patient navigator's role in latent tuberculosis infection at a New York City Health Department Chest Clinic

Background

Philippines is one of the top ten countries of birth among individuals with tuberculosis in New York City (NYC). The NYC Health Department (HD) screened Filipino-born New Yorkers for latent TB infection (LTBI), but few of those tested positive completed evaluation and treatment.

Objective

To increase the proportion of Filipinos with a positive QuantiFeron-TB Gold Plus (QFT-Plus) complete LTBI evaluation and treatment.

Methods

Nine community-based LTBI screening events were conducted during September-December 2021. Patients with positive QFT-Plus results were offered no-cost LTBI evaluation and treatment at HD Chest Clinic. The HD engaged culturally- and linguistically-competent Filipino patient navigators (PN) to facilitate LTBI evaluation and treatment.

Results

Of 77 Filipinos screened, 17 (22%) tested positive. Fourteen (82%) were evaluated for LTBI; eight of the 14 (57%) completed LTBI treatment.

Conclusions

Pairing patients with culturally- and linguistically- competent Filipino PNs contributed to an increase in the proportion of Filipinos with a positive QFT-Plus who completed LTBI evaluation and treatment. TB prevention programs may wish to consider PNs in LTBI patient care.

Metabolism-based category formation for the prioritisation of genotoxicity hazard assessment for plant protection product residues (Part 4): α-Chloroacetamides

In dietary risk assessment of plant protection products, residues of active ingredients and their metabolites need to be evaluated for their genotoxic potential. The European Food Safety Authority recommend a tiered approach focussing assessment and testing on classes of similar chemicals. To characterise similarity, in terms of metabolism, a metabolic similarity profiling scheme has been developed from an analysis of 69 α-chloroacetamide herbicides for which either Ames, chromosomal aberration or micronucleus test results are publicly available. A set of structural space alerts were defined, each linked to a key metabolic transformation present in the α-chloroacetamide metabolic space. The structural space alerts were combined with covalent chemistry profiling to develop categories suitable for chemical prioritisation via read-across. The method is a robust and reproducible approach to such read-across predictions, with the potential to reduce unnecessary testing. The key challenge in the approach was identified as being the need for metabolism data individual groups of plant protection products as the basis for the development of the structural space alerts.

Vesical Imaging-Reporting and Data System (VI-RADS) as a grouping imaging biomarker combined with a decision-tree mode to preoperatively predict the pathological grade of bladder cancer

AIM

To investigate whether the Vesical Imaging-Reporting and Data System (VI-RADS) could be used to develop a new non-invasive preoperative grade-prediction system to partially predict high-grade bladder cancer (HG-BC).

MATERIALS AND METHODS

The present study enrolled 89 primary BC patients prospectively from March 2022 to June 2023. Receiver operating characteristic (ROC) curve analysis was performed to evaluate the diagnostic performance of VI-RADS for predicting HG-BC and muscle-invasive bladder cancer (MIBC) in the entire group. In the low VI-RADS (≤2) group, the decision tree-based method was used to obtain significant predictors and construct the decision-tree model (DT model). The performance of the DT model and low VI-RADS scores for predicting HG-BC was determined using ROC, calibration, and decision curve analyses.

RESULTS

At a cut-off of ≥3, the specificity and positive predictive value of VI-RADS for predicting HG-BC in the entire group was 100%, and the area under the ROC curve (AUC) was 0.697. Among 65 patients with low VI-RADS scores, the DT model showed an AUC of 0.884 in predicting HG-BC compared to 0.506 for low VI-RADS scores. Calibration and decision curve analyses showed that the DT model performed better than the low VI-RADS scores.

CONCLUSION

Most VI-RADS scores ≥3 correspond to HG-BCs. VI-RADS could be used as a grouping imaging biomarker for a pathological grade-prediction procedure, which in combination with the DT model for low VI-RADS (≤2) populations, would provide a potential preoperative non-invasive method of predicting HG-BC.

Phase II trial of domatinostat (4SC-202) in combination with avelumab in patients with previously treated advanced mismatch repair proficient oesophagogastric and colorectal adenocarcinoma: EMERGE

BACKGROUND

Most oesophagogastric adenocarcinomas (OGAs) and colorectal cancers (CRCs) are mismatch repair proficient (MMRp), responding poorly to immune checkpoint inhibition. We evaluated the safety and efficacy of domatinostat (histone deacetylase inhibitor) plus avelumab (anti-PD-L1 antibody) in patients with previously treated inoperable, advanced/metastatic MMRp OGA and CRC.

PATIENTS AND METHODS

Eligible patients were evaluated in a multicentre, open-label dose escalation/dose expansion phase II trial. In the escalation phase, patients received escalating doses of domatinostat [100 mg once daily (OD), 200 mg OD, 200 mg twice daily (BD)] orally for 14 days followed by continuous dosing plus avelumab 10 mg/kg administered intravenously 2-weekly (2qw) to determine the recommended phase II dose (RP2D). The trial expansion phase evaluated the best objective response rate (ORR) during 6 months by RECIST version 1.1 using a Simon two-stage optimal design with 2/9 and 1/10 responses required to proceed to stage 2 in the OGA and CRC cohorts, respectively.

RESULTS

Patients (n = 40) were registered between February 2019 and October 2021. Patients in the dose escalation phase (n = 12) were evaluated to confirm the RP2D of domatinostat 200 mg BD plus avelumab 10 mg/kg. No dose-limiting toxicities were observed. Twenty-one patients were treated at the RP2D, 19 (9 OGA and 10 CRC) were assessable for the best ORR; 2 patients with CRC did not receive combination treatment and were not assessable for the primary endpoint analysis. Six patients were evaluated in the dose escalation and expansion phases. In the OGA cohort, the best ORR was 22.2% (95% one-sided confidence interval lower bound 4.1) and the median duration of disease control was 11.3 months (range 9.9-12.7 months). No responses were observed in the CRC cohort. No treatment-related grade 3-4 adverse events were reported at the RP2D.

CONCLUSIONS

Responses in the OGA cohort met the criteria to expand to stage 2 of recruitment with an acceptable safety profile. There was insufficient signal in the CRC cohort to progress to stage 2.

TRIAL REGISTRATION

NCT03812796 (registered 23rd January 2019).

Mechanism and cellular function of direct membrane binding by the ESCRT and ERES-associated Ca2+-sensor ALG-2

Apoptosis linked Gene-2 (ALG-2) is a multifunctional intracellular Ca2+ sensor and the archetypal member of the penta-EF hand protein family. ALG-2 functions in the repair of damage to both the plasma and lysosome membranes and in COPII-dependent budding at endoplasmic reticulum exit sites (ERES). In the presence of Ca2+, ALG-2 binds to ESCRT-I and ALIX in membrane repair and to SEC31A at ERES. ALG-2 also binds directly to acidic membranes in the presence of Ca2+ by a combination of electrostatic and hydrophobic interactions. By combining giant unilamellar vesicle-based experiments and molecular dynamics simulations, we show that charge-reversed mutants of ALG-2 at these locations disrupt membrane recruitment. ALG-2 membrane binding mutants have reduced or abrogated ERES localization in response to Thapsigargin-induced Ca2+ release but still localize to lysosomes following lysosomal Ca2+ release. In vitro reconstitution shows that the ALG-2 membrane-binding defect can be rescued by binding to ESCRT-I. These data thus reveal the nature of direct Ca2+-dependent membrane binding and its interplay with Ca2+-dependent protein binding in the cellular functions of ALG-2.

Three-step docking by WIPI2, ATG16L1, and ATG3 delivers LC3 to the phagophore

The covalent attachment of ubiquitin-like LC3 proteins (microtubule-associated proteins 1A/1B light chain 3) prepares the autophagic membrane for cargo recruitment. We resolve key steps in LC3 lipidation by combining molecular dynamics simulations and experiments in vitro and in cellulo. We show how the E3-like ligaseautophagy-related 12 (ATG12)-ATG5-ATG16L1 in complex with the E2-like conjugase ATG3 docks LC3 onto the membrane in three steps by (i) the phosphatidylinositol 3-phosphate effector protein WD repeat domain phosphoinositide-interacting protein 2 (WIPI2), (ii) helix α2 of ATG16L1, and (iii) a membrane-interacting surface of ATG3. Phosphatidylethanolamine (PE) lipids concentrate in a region around the thioester bond between ATG3 and LC3, highlighting residues with a possible role in the catalytic transfer of LC3 to PE, including two conserved histidines. In a near-complete pathway from the initial membrane recruitment to the LC3 lipidation reaction, the three-step targeting of the ATG12-ATG5-ATG16L1 machinery establishes a high level of regulatory control.

Benefits of routine probiotic supplementation in preterm infants

AIM

We introduced routine probiotic supplementation (RPS) of preterm infants in June 2012. We previously reported that RPS reduced the incidence of necrotising enterocolitis (NEC) and mortality in such infants. In this study, we assessed if the benefits of RPS were sustained for infants in the current era.

METHOD

We compared the outcomes of preterm infants in recent epoch 3 (RPS, 1st June 2014 to 31st December 2019) versus epoch 2 (RPS, 1st June 2012 to 31st May 2014) and epoch 1 (no RPS, 1st December 2008 to 30th November 2010). Multiple logistic and Cox regression models were used to compare the outcomes.

RESULTS

There were 645 infants in epoch 1, 712 in epoch 2 and 1715 in epoch 3. Age at full feeds was significantly lower in epoch 3 vs. 2 and epoch 3 vs. 1 in infants <28 weeks of gestation. NEC and late-onset sepsis (LOS) were significantly lower in epoch 3 vs. 1 in infants <28 weeks. LOS and age at full feeds were significantly lower in epoch 3 vs. 2 and epoch 3 vs. 1 in infants with gestation 28 to 32 weeks.

CONCLUSION

The benefits associated with RPS were sustained during epoch 3.

Mechanism and cellular function of direct membrane binding by the ESCRT and ERES-associated Ca2+-sensor ALG-2

Apoptosis Linked Gene-2 (ALG-2) is a multifunctional intracellular Ca2+ sensor and the archetypal member of the penta-EF hand protein family. ALG-2 functions in the repair of damage to both the plasma and lysosome membranes and in COPII-dependent budding at endoplasmic reticulum exit sites (ERES). In the presence of Ca2+, ALG-2 binds to ESCRT-I and ALIX in membrane repair and to SEC31A at ERES. ALG-2 also binds directly to acidic membranes in the presence of Ca2+ by a combination of electrostatic and hydrophobic interactions. By combining GUV-based experiments and molecular dynamics simulations, we show that charge-reversed mutants of ALG-2 at these locations disrupt membrane recruitment. ALG-2 membrane binding mutants have reduced or abrogated ERES localization in response to Thapsigargin-induced Ca2+ release but still localize to lysosomes following lysosomal Ca2+ release. In vitro reconstitution shows that the ALG-2 membrane-binding defect can be rescued by binding to ESCRT-I. These data thus reveal the nature of direct Ca2+-dependent membrane binding and its interplay with Ca2+-dependent protein binding in the cellular functions of ALG-2.

Metabolism-based category formation for the prioritisation of genotoxicity hazard assessment for plant protection product residues (part 3): Strobilurins

In dietary risk assessment of plant protection products, residues of active ingredients and their metabolites need to be evaluated for their genotoxic potential. The European Food Safety Authority recommend a tiered approach focussing assessment and testing on classes of similar chemicals. To characterise similarity, in terms of metabolism, a metabolic similarity profiling scheme has been developed from an analysis of 46 chemicals of strobilurin fungicides and their metabolites for which either Ames, chromosomal aberration or micronucleus test results are publicly available. This profiling scheme consists of a set of ten sub-structures, each linked to a key metabolic transformation present in the strobilurin metabolic space. This metabolic similarity profiling scheme was combined with covalent chemistry profiling and physico-chemistry properties to develop chemical categories suitable for chemical prioritisation via read-across. The method is a robust and reproducible approach to such read-across predictions, with the potential to reduce unnecessary testing. The key challenge in the approach was identified as being the need for metabolism data and individual groups of plant protection products as the basis for the development of such profiling schemes.

A Phase 1 Trial of the Safety, Tolerability, and Biological Effects of Intravenous Enadenotucirev (EnAd), a Novel Oncolytic Virus, in Combination with Chemoradiotherapy in Locally Advanced Rectal Cancer (CEDAR)

PURPOSE/OBJECTIVE(S)

Novel treatment combinations are required to increase response rates in rectal cancer. EnAd is an intravenous, tumor selective, oncolytic adenovirus with high affinity for malignant colorectal epithelial cells. Pre-clinical evidence of synergy with radiation warranted further clinical evaluation and assessment of safety in combination with chemoradiation (CRT), 25 × 2Gy and concurrent capecitabine.

MATERIALS/METHODS

EnAd was escalated using 2 dose levels of viral particles (1 × 1012, 3 × 1012), given Monday, Wednesday, Friday over 3 schedules (pre-CRT, pre & post CRT). Toxicity and efficacy were used as dual end points in escalation decisions. A 2-parameter and 3-parameter logistic Time to Event Continual Reassessment Method (TiTE-CRM) were used estimate the dose-toxicity and dose-efficacy relationship, respectively. Results are shown as probability and 95% credible interval (Cr.I). The dose limiting toxicity (DLT) window was 13 weeks. Patients who had not completed their DLT window at the time of a dose decision were included in the safety analysis but down-weighted according to their follow-up time and amount of IMP received. Efficacy was assessed at 13 weeks using MRI Tumor Regression Grade (mrTRG), where mrTRG 1-2 equals response. The trial (NCT03916510) was conducted in 4 UK centers.

RESULTS

A total of 13 patients were enrolled, 12 of whom were evaluable. Median age was 57 (range 31-84), and 10/13 were male. One patient had two G3 adverse events (AE); diarrhea, acute kidney injury. All other adverse events (AEs) were G1 or 2, with no G4/5 events. The most common AE by organ system was gastrointestinal (20.8%, G1). There were two observed DLTs on Dose schedule 3; leg swelling and acute kidney injury. Responses and toxicities increased with escalating schedules of EnAd (Table 1).

CONCLUSION

CEDAR is the first trial to successfully combine an intravenous oncolytic adenovirus with radiation, demonstrating the feasibility and acceptability of this approach, and a new paradigm in radiosensitization in rectal cancer. Within this small Phase I study, EnAd demonstrated an acceptable safety profile with evidence of a higher-than-expected rate of response by mrTRG. Translation analysis of tissue, blood and microbiome for biological correlates of radiation synergy is underway.

FUNDING

PsiOxus, CRUK (A24474).

SPONSOR

University of Oxford.

Development of a novel immobilisation protocol for black-faced impala (Aepyceros melampus ssp. petersi) in Etosha National Park

Black-faced impala (Aepyceros melampus ssp. petersi) are endemic to Namibia where conservation management involves immobilisation and translocation, and mortality with current protocols is common. Critically evaluated field immobilisation protocols are needed to maximise animal safety. This prospective study was done in two phases: the first compared etorphine- and thiafentanil-based combinations, the second evaluated the influence of oxygen in impala receiving the thiafentanil-based combination. Animals (10 per group) received 50 mg ketamine (K) and 10 mg butorphanol (B), with either 2.0 mg etorphine (E) or 2.0 mg thiafentanil (T). A third group of ten impala were anaesthetised using TKB with supplemental nasal oxygen (O) at a rate of 5 L/minute. Behavioural, metabolic and physiological variables were assessed within five minutes of recumbency and at 10, 15, and 20 minutes post-recumbency. Statistical analyses for non-parametric data were performed to compare the treatment groups as well as time points; p ≤ 0.05 considered significant. Following darting, 7/10 EKB animals were standing when approached, compared to 2/20 in the thiafentanil treatment groups. Time to first effect was significantly higher for EKB (155 ± 105.7 seconds) compared to TKBO (61.5 ± 21.4 seconds). Time to sternal after darting was significantly higher with EKB (411.6 ± 174 seconds) compared to TKB (160.5 ± 85.4 seconds) and TKBO (166 ± 77.3 seconds). This study builds on previous work investigating the effects of potent opioids on impala and is the first evaluating their use in a field setting. The thiafentanil combination had a faster onset and resulted in a smoother induction than the etorphine combination. Additionally, oxygenation improved in animals receiving oxygen supplementation.

Radiation dose during interventional cardiology procedures: portable C-arm vs. a new generation fluoroscopy system

INTRODUCTION

Occupational exposure to ionizing radiation poses health risks for veterinary interventionalists. There are limited veterinary studies evaluating radiation dose in the cardiac catheterization laboratory. The purpose of this study was to report direct radiation dose exposure to patients during common interventional cardiology procedures and compare these doses between two fluoroscopy units.

ANIMALS

One hundred and fifty-four client-owned dogs.

MATERIALS AND METHODS

Patient dose during procedures using a portable C-arm were retrospectively analyzed and compared to those performed in a contemporary interventional suite. Fluoroscopy equipment, procedure type, operator, patient weight, fluoroscopy time, dose area product, and air kerma were recorded and statistically modeled using univariable and multivariable linear regression to evaluate the effect of each factor.

RESULTS

Patient dose population (154 dogs), comprised 61 patent ductus arteriosus occlusions, 60 balloon pulmonary valvuloplasties, and 33 pacemaker implantations. Patient dose was significantly lower in the group utilizing a newer generation fluoroscopy unit vs. the group utilizing an older portable C-arm, positively correlated with patient weight, and highest during balloon pulmonary valvuloplasties compared to patent ductus arteriosus occlusions or pacemaker implantations (all p<0.010).

DISCUSSION

Newer fluoroscopy systems can be equipped with technologies that improve image quality while reducing patient dose and radiation exposure to interventional personnel.

CONCLUSIONS

We documented a significant reduction in patient radiation dose using a newer fluoroscopy system as compared to an older portable C-arm for interventional cardiology procedures in animals. Improved knowledge of patient radiation dose factors may promote better radiation safety protocols in veterinary interventional cardiology.

Effectiveness of Preparedness Training Delivered to Pre-final and Final Year Nursing Undergraduates to Combat COVID-19: A Need-based Initiative

A major concern during the COVID-19 pandemic has been the shortage of manpower for patient care. The recommendation of various authorised bodies encouraged the training of students from medical, nursing, and allied fields to manage COVID-19 cases by tele-consultation and monitoring of mild cases under the supervision of faculty. Anticipating a further shortage of human resources, leading to dire consequences, preparedness training for the final year and pre-final nursing undergraduates was initiated. The current study was conducted to evaluate the effectiveness of and feedback on COVID-19 preparedness training delivered to final-and pre-final-year undergraduate nursing students. A 3-day training was given to pre-final and final year nursing undergraduates on ECG, COVID-19 management protocols, personal protective equipment "donning and doffing", "hand hygiene", "biomedical waste management", "contact tracing" and cleaning and disinfection and simulation-based skills. Scores before and after training were conducted and mean scores were compared using a paired t-test. In total, 154 nursing students participated in the training program. Mean pre-test and post-test scores included: general instructions (21.69±2.5 and 25.09±3.29); skill procedures (5.4±1.21 and 6.3±1.2) and COVID management (22.84±3.26 and 26.48±2.06). There was a statistically significant improvement in knowledge and skills in all training sessions (p=0.0001). The mean post-test scores obtained at the OSCE stations for cardiac monitoring, prone positioning, compression-only CPR, airway, ECG and ABG ranged from 97.0% to 100.0% and all participants scored >70.0%. About 92.8% of the students felt that hands-on training enhanced their learning experiences. A need-based initiative of training final-and pre-final-year nursing students in COVID-19 support care effectively and efficiently created a skilled workforce.

Membrane curvature sensing and stabilization by the autophagic LC3 lipidation machinery

How the highly curved phagophore membrane is stabilized during autophagy initiation is a major open question in autophagosome biogenesis. Here, we use in vitro reconstitution on membrane nanotubes and molecular dynamics simulations to investigate how core autophagy proteins in the LC3 (Microtubule-associated proteins 1A/1B light chain 3) lipidation cascade interact with curved membranes, providing insight into their possible roles in regulating membrane shape during autophagosome biogenesis. ATG12(Autophagy-related 12)-ATG5-ATG16L1 was up to 100-fold enriched on highly curved nanotubes relative to flat membranes. At high surface density, ATG12-ATG5-ATG16L1 binding increased the curvature of the nanotubes. While WIPI2 (WD repeat domain phosphoinositide-interacting protein 2) binding directs membrane recruitment, the amphipathic helix α2 of ATG16L1 is responsible for curvature sensitivity. Molecular dynamics simulations revealed that helix α2 of ATG16L1 inserts shallowly into the membrane, explaining its curvature-sensitive binding to the membrane. These observations show how the binding of the ATG12-ATG5-ATG16L1 complex to the early phagophore rim could stabilize membrane curvature and facilitate autophagosome growth.

Effects of distal radial access vs conventional radial access in patients undergoing coronary angiography and/or intervention: a meta-analysis of randomised trials

Background

Recently the distal radial access (DRA) technique has been introduced for coronary angiography and intervention as an alternative to the conventional radial access (RA).

Purpose

The aim of this study was to provide a quantitative appraisal of the effects of DRA vs conventional RA for coronary angiography with or without intervention.

Methods

The PubMed, Embase, Cochrane Central Register of Controlled Trials, and ClinicalTrials.gov databases were searched for randomised clinical trials (RCT) comparing DRA versus RA for coronary angiography and/or intervention. Data were pooled by meta-analysis using a random-effects model. The number of patients needed to treat for an additional beneficial outcome (NNTB) and the number needed to treat for an additional harmful outcome (NNTH) were calculated. The primary endpoint was radial artery occlusion (RAO) at the longest available follow-up. Additional secondary outcomes were assessed.

Results

A total of 13 RCT including 4,901 patients were identified and included in the final analysis. Coronary angiography alone was performed in 3 studies, percutaneous coronary intervention was performed in a variable proportion of patients ranging from 24% to 100% across studies. Study population included patients with chronic coronary syndrome in the large majority, and the proportion of acute coronary syndrome ranged from to 31% to 100% across studies. Compared with RA, DRA was associated with a significant lower risk of RAO, either detected at the longest follow-up (risk ratio [RR]: 0.36; 95% CI: 0.23 to 0.58; p&lt;0.001, NNTB = 24.5), or in-hospital (RR: 0.32; 95% CI: 0.18 to 0.57; p&lt;0.001, NNTB = 21.5), as well as Early discharge after transradial stenting of coronary arteries (EASY) Scale ≥ II hematoma (RR: 0.46; 95% CI: 0.22 to 0.97; p=0.04, NNTB = 66). By contrast, DRA was associated with a higher risk of access site crossover (RR: 3.43; 95% CI: 1.88 to 6.25, p&lt;0.001, NNTH = 10), a longer time for radial artery puncture (standardized mean difference [SMD]: 3.56; 95% CI: 0.96 to 6.16; p&lt;0.001), and sheath insertion (SMD: 0.38; 95% CI: 0.11 to 0.65, p=0.006), and a higher number of puncture attempts (SMD: 0.59, 95% CI: 0.48 to 0.69, p&lt;0.001). A meta-regression analysis showed that increasing age in the RA group was associated with a reduced effect of DRA, compared with RA, on the risk of RAO. No significant effect of other variables such as the prevalence of female sex, diabetes, smoking status, acute coronary syndrome, and percutaneous coronary intervention was found.

Conclusions

Compared with RA, DRA is associated with lower risks of RAO and EASY ≥ II hematoma, but requires longer time for radial artery puncture and sheath insertion, more puncture attempts and a higher access site crossover.

Funding Acknowledgement

Type of funding sources: None.

Gain-of-function mutations in KCNK3 cause a developmental disorder with sleep apnea

Sleep apnea is a common disorder that represents a global public health burden. KCNK3 encodes TASK-1, a K+ channel implicated in the control of breathing, but its link with sleep apnea remains poorly understood. Here we describe a new developmental disorder with associated sleep apnea (developmental delay with sleep apnea, or DDSA) caused by rare de novo gain-of-function mutations in KCNK3. The mutations cluster around the 'X-gate', a gating motif that controls channel opening, and produce overactive channels that no longer respond to inhibition by G-protein-coupled receptor pathways. However, despite their defective X-gating, these mutant channels can still be inhibited by a range of known TASK channel inhibitors. These results not only highlight an important new role for TASK-1 K+ channels and their link with sleep apnea but also identify possible therapeutic strategies.

Advances in physiological mechanisms of selenium to improve heavy metal stress tolerance in plants

Selenium (Se) is a metalloid mineral nutrient for human and animal health. Plants are the main foodstuff source of the Se intake of humans. For plants, the addition of an appropriate amount of Se could promotes growth and development, and improves the tolerance to environmental stress, especially stress from some of heavy metals (HM) stress, such as cadmium (Cd) and mercury (Hg). This paper mainly reviews and summarizes the physiological mechanism of Se in enhancing HM stress tolerance in plants. The antagonistic effect of Se on HM is a comprehensive effect that includes many physiological mechanisms. Se can promote the removal of excessive reactive oxygen species and reduce the oxidative damage of plant cells under HM elements stress. Se participates in the regulation of the transportation and distribution of HM ions in plants, and alleviates the damage caused by of HM stress. Moreover, Se combine with HM elements to form Se-HM complexes and promote the production of phytochelatins (PCs), thereby reducing the accumulation of HM ions in plants. Overall, Se plays an important role in plant response to HM stress, but current studies mainly focus on physiological mechanism, and further in-depth study on the molecular mechanism is essential to confirm the participation of Se in plant response to environmental stress. This review helps to comprehensively understand the physiological mechanism of Se in plant tolerance against to HM stress of plants, and provides important theoretical support for the practical application of Se in environmental remediation and agricultural development.

Structural basis for cannabinoid-induced potentiation of alpha1-glycine receptors in lipid nanodiscs

Nociception and motor coordination are critically governed by glycine receptor (GlyR) function at inhibitory synapses. Consequentially, GlyRs are attractive targets in the management of chronic pain and in the treatment of several neurological disorders. High-resolution mechanistic details of GlyR function and its modulation are just emerging. While it has been known that cannabinoids such as Δ9-tetrahydrocannabinol (THC), the principal psychoactive constituent in marijuana, potentiate GlyR in the therapeutically relevant concentration range, the molecular mechanism underlying this effect is still not understood. Here, we present Cryo-EM structures of full-length GlyR reconstituted into lipid nanodisc in complex with THC under varying concentrations of glycine. The GlyR-THC complexes are captured in multiple conformational states that reveal the basis for THC-mediated potentiation, manifested as different extents of opening at the level of the channel pore. Taken together, these structural findings, combined with molecular dynamics simulations and functional analysis, provide insights into the potential THC binding site and the allosteric coupling to the channel pore.

Effect of a 2-step probiotic program on digestive health and performance of Holstein heifer calves

Managing the composition of the bacterial communities in the digestive tract with the use of probiotics that enhance protective microflora could result in positive effects on health and performance of calves. The objective of this study was to evaluate a 2-step probiotic program (added to colostrum and milk) on the digestive health and growth of preweaning Holstein heifers. A randomized clinical trial was conducted from July to October 2020 in a calf rearing facility in Colorado. Calves were housed in pairs sharing the same treatment in 2 polyethylene hutches within a common area of 4.50 m². A total of 232 calves were enrolled at birth and randomly allocated into 2 treatment groups [control (CTR) = 116; treatment (PB) = 116] and followed until weaning (64 ± 3 d). Treatment consisted of 2 formulations of a multistrain bacterial-based probiotic added in colostrum (PBF1) and milk (PBF2). Treatment calves received 2 g of PBF1 added to each colostrum feeding, and 1 g of PBF2 added to the milk at the morning feeding 3 times per week up to weaning. Calf weight was collected at birth, at 30 d of age, and at weaning. Serum total protein was determined at age 3 ± 1 d and a health assessment was completed 3 times per week. Statistical analyses were performed using SAS, with calf considered the experimental unit clustered by housing pair. Cox proportional hazard analysis and time to event analysis were used to compare time to the first diarrhea event and time to recovery between treatment groups. The total number of diarrhea events and culling were assessed by Poisson regression and logistic regression analysis, respectively. Linear regression was performed to evaluate differences in average daily gain by treatment group. Overall, the mean (± standard error) temperature humidity index (THI) was 75 (± 0.44) units during the study period, which resulted in continuous exposure to heat stress in the day hours. No difference between treatment groups was observed in serum total protein. The overall incidence of diarrhea was 96.6% (CTR = 99%, PB = 95%); no differences were determined in the hazard of a first diarrhea episode or in the median time to the first diarrhea event (11 d in both groups). Similarly, no differences were found in the likelihood of recovery or in the median time to recovery from diarrhea (7 d in both groups). Likewise, treatment group was not associated with the number of diarrhea events, mean (± standard error, g/d) average daily gain from birth to weaning [CTR = 562.5 (13.9); PB = 570.8 (13.5)], or with the odds of culling. The most prevalent pathogen isolated from feces was Clostridium, which tended to be more frequent in CTR calves than PB calves. In conclusion, the probiotic program did not affect the incidence of enteric disease or the growth of preweaning heifer calves.

A phase II study of retifanlimab (INCMGA00012) in patients with squamous carcinoma of the anal canal who have progressed following platinum-based chemotherapy (POD1UM-202)

Background

Locally advanced or metastatic squamous carcinoma of the anal canal (SCAC) has poor prognosis following platinum-based chemotherapy. Retifanlimab (INCMGA00012), a humanized monoclonal antibody targeting programmed death protein-1 (PD-1), demonstrated clinical activity across a range of solid tumors in clinical trials. We present results from POD1UM-202 (NCT03597295), an open-label, single-arm, multicenter, phase II study evaluating retifanlimab in patients with previously treated advanced or metastatic SCAC.

Patients and methods

Patients ≥18 years of age had measurable disease and had progressed following, or were ineligible for, platinum-based therapy. Retifanlimab 500 mg was administered intravenously every 4 weeks. The primary endpoint was overall response rate (ORR) by independent central review. Secondary endpoints were duration of response (DOR), disease control rate (DCR), progression-free survival (PFS), overall survival (OS), and safety.

Results

Overall, 94 patients were enrolled. At a median follow-up of 7.1 months (range, 0.9-19.4 months), ORR was 13.8% [95% confidence interval (CI) 7.6% to 22.5%], with one complete response (1.1%) and 12 partial responses (12.8%). Responses were observed regardless of human immunodeficiency virus or human papillomavirus status, programmed death ligand 1 (PD-L1) expression, or liver metastases. Stable disease was observed in 33 patients (35.1%) for a DCR of 48.9% (95% CI 38.5% to 59.5%). Median DOR was 9.5 months (range, 5.6 months-not estimable). Median (95% CI) PFS and OS were 2.3 (1.9-3.6) and 10.1 (7.9-not estimable) months, respectively. Retifanlimab safety in this population was consistent with previous experience for the PD-(L)1 inhibitor class.

Conclusions

Retifanlimab demonstrated clinically meaningful and durable antitumor activity, and an acceptable safety profile in patients with previously treated locally advanced or metastatic SCAC who have progressed on or are intolerant to platinum-based chemotherapy.

•

Retifanlimab (PD-1 inhibitor) monotherapy demonstrated encouraging results in patients with platinum-refractory SCAC.

•

Clinically meaningful antitumor activity was reported with ORR of 13.8% and stable disease in 35.1%, for a DCR of 48.9%.

•

Observed responses in advanced SCAC were durable (median 9.5 months).

•

Acceptable safety profile consistent with that reported for the PD-(L)1 inhibitor class.

•

Promising results warrant further investigation of retifanlimab in advanced SCAC as well as earlier stages of disease.

CT volumetry helps predict prognosis of large hepatocellular carcinoma after resection

AIM

To determine whether the tumour volume measurement on preoperative contrast-enhanced computed tomography (CT) could be used to predict the overall survival patients with large hepatocellular carcinoma (>5 cm) after resection.

MATERIALS AND METHODS

This study included 171 patients with surgically confirmed hepatocellular carcinoma who underwent preoperative CT. The largest diameter, the product of the axial dimension, tumour volume, and tumour-to-liver volume ratio (TTLVR) on CT images were measured and calculated. The univariate and multivariate Cox proportional hazard ratio regression models were used to identify the impact of the tumour burden-related risk factors on overall survival.

RESULTS

In multivariate analysis, TTLVR (p=0.042) and major vascular invasion (p=0.006) were independently associated with overall survival of patients with hepatocellular carcinoma after the resection. The group in which the patients had a low TTLVR showed higher cumulative survival rates than patients with a TTLVR (p=0.004). Patients with a low TTLVR (≤26.23%) and absence of major vascular invasion had significantly higher cumulative survival rates compared to those patients with hepatocellular carcinoma with either or both the risk factors (p=0.001).

CONCLUSION

A higher TTLVR in combination with the presence of major vascular invasion was associated with poorer overall survival in patients with large hepatocellular carcinoma after resection.

OUTCOMES OF NEONATAL CHYLOUS EFFUSIONS: A 20-YEAR WEST-AUSTRALIAN TERTIARY CENTER EXPERIENCE

Neonatal chylous effusions are rare entity with limited evidence-based management. We conducted a retrospective review of neonates admitted to King Edward Memorial and Princess Margaret/Perth Children's Hospital over 20 years with laboratory-confirmed chylous effusions. A total of 51 infants with chylous effusion were identified. Median gestational age and birth weight were 35.5 weeks and 2620 grams respectively. Congenital [27/51] and acquired [24/51] cases were included. Antenatal interventions were performed in 17/22 with antenatal hydrops and 50/51 needed postnatal drains. Effusions were monitored with serial (≥2) chest ultrasounds in 29/51 infants and multiple (≥5) x-rays in 45/51 infants. Median duration of mechanical ventilation, oxygen requirement, and hospital stay was 294.5 hours, 400 hours, and 49 days respectively. 39/51 received medium chain triglyceride (MCT) diet while 8/51 received octreotide. Six infants died during hospital stay. 12/19 had normal developmental assessment at one-year. The acquired group had higher number of xrays done, need for MCT diet and inotropes, and hospital stay vs congenital group. Duration of drains, radiological investigations and immunoglobulin administration were higher in neonates who received octreotide. Syndromic association, duration of ventilation and oxygenation were risk factors for mortality. In our setting, neonatal chylous effusions are associated with significant morbidity and mortality.

Sub-structure-based category formation for the prioritisation of genotoxicity hazard assessment for pesticide residues: Sulphonyl ureas

In dietary risk assessment, residues of pesticidal ingredients or their metabolites need to be evaluated for their genotoxic potential. The European Food Safety Authority recommend a tiered approach focussing assessment and testing on classes of similar chemicals. To characterise similarity and to identify structural alerts associated with genotoxic concern, a set of chemical sub-structures was derived for an example dataset of 74 sulphonyl urea agrochemicals for which either Ames, chromosomal aberration or micronucleus test results are publicly available. This analysis resulted in a set of seven structural alerts that define the chemical space, in terms of the common parent and metabolic scaffolds, associated with the sulphonyl urea chemical class. An analysis of the available profiling schemes for DNA and protein reactivity shows the importance of investigating the predictivity of such schemes within a well-defined area of structural space. Structural space alerts, covalent chemistry profiling and physico-chemistry properties were combined to develop chemical categories suitable for chemical prioritisation. The method is a robust and reproducible approach to such read-across predictions, with the potential to reduce unnecessary testing. The key challenge in the approach was identified as being the need for pesticide-class specific metabolism data as the basis for structural space alert development.

Water Nanoconfined in a Hydrophobic Pore: Molecular Dynamics Simulations of Transmembrane Protein 175 and the Influence of Water Models

Water molecules within biological ion channels are in a nanoconfined environment and therefore exhibit behaviors which differ from that of bulk water. Here, we investigate the phenomenon of hydrophobic gating, the process by which a nanopore may spontaneously dewet to form a "vapor lock" if the pore is sufficiently hydrophobic and/or narrow. This occurs without steric occlusion of the pore. Using molecular dynamics simulations with both rigid fixed-charge and polarizable (AMOEBA) force fields, we investigate this wetting/dewetting behavior in the transmembrane protein 175 ion channel. We examine how a range of rigid fixed-charge and polarizable water models affect wetting/dewetting in both the wild-type structure and in mutants chosen to cover a range of nanopore radii and pore-lining hydrophobicities. Crucially, we find that the rigid fixed-charge water models lead to similar wetting/dewetting behaviors, but that the polarizable water model resulted in an increased wettability of the hydrophobic gating region of the pore. This has significant implications for molecular simulations of nanoconfined water, as it implies that polarizability may need to be included if we are to gain detailed mechanistic insights into wetting/dewetting processes. These findings are of importance for the design of functionalized biomimetic nanopores (e.g., sensing or desalination) as well as for furthering our understanding of the mechanistic processes underlying biological ion channel function.

The prevalence and safety of direct oral anticoagulants in patients with non-atrial fibrillation associated intra-cardiac thrombus

Background

The standard of care in management of intra-cardiac thrombus has been the use of vitamin K antagonists (VKAs). The emergence and use of direct oral anticoagulants (DOACs) in other conditions has led to the consideration of their use in patients with intra-cardiac thrombus. Thus far, case-reports have provided the majority of data regarding the efficacy of DOACs in this population.

Purpose

The aim of this observational study was to investigate the safety and efficacy of DOACs in intracardiac thrombus not associated with atrial fibrillation, compared to the current standard of care, VKAs.

Methods

An observational study was conducted between 10 hospitals in our region. The study was conducted between 2013 and 2019 in patients with a diagnosis of intracardiac thrombus. All left and right, atrial and ventricular thrombi were included. Patients with atrial fibrillation were excluded. Patient information was collected from the hospital electronic record. The primary endpoints were clinically significant bleeding requiring transfusion and thromboembolic events, excluding myocardial infarction.

Results

1153 patients had a diagnosis of intracardiac thrombus. 878 out of 1153 patients were discharged on warfarin and 275 were discharged on a DOAC. In the warfarin population 73 of 878 patients (8.3%) had clinically significant bleeding events compared to 21 of 275 patients (7.6%) in the DOAC population (p=0.801). The median ages were 60.5 and 58 respectively. The median time period to a bleeding event was 151 and 198 days respectively. In the warfarin population, 116 of 878 patients (13.2%) had thromboembolic disease versus 34 of 275 patients (12.4%) in the DOAC arm (p=0.759). The median ages were 62 and 62.5 respectively. The median time period to a thromboembolic event was 114 and 184 days respectively. In the warfarin arm, 3 patients had systemic thromboembolism and 113 patients had embolic strokes. In the DOAC arm, 2 patients had systemic thromboembolism, 32 patients had embolic strokes.

Conclusion

The data from this study suggests that DOACs may be a feasible alternative to warfarin in patients with intracardiac thrombus. There was no statistically significant difference in the rates of clinically significant bleeding or in incidence of thromboembolic disease. To our knowledge, this is the largest observational study to date on this topic. Randomized controlled trials are needed to fully establish the efficacy of DOACs in this patient population.

Funding Acknowledgement

Type of funding sources: None. Table 1