Sex Bias in Prediction and Diagnosis of Cardiac Surgery Associated Acute Kidney Injury

Background

Female sex has been recognized as a risk factor for cardiac surgery associated acute kidney injury (CS-AKI). The current study sought to evaluate whether female sex is a risk factor for CS-AKI, or modifies the association of peri-operative change in serum creatinine with CS-AKI.

Methods

Observational study of adult patients undergoing cardiac surgery between 2000 and 2019 in a single U.S. center. The main variable of interest was registered patient sex, identified from electronic medical records. The main outcome was CS-AKI within 2 weeks of surgery.

Results

Of 58526 patients, 19353 (33%) were female; 12934 (22%) incurred AKI based on ≥ 0.3 mg/dL or ≥ 50% rise in serum creatinine (any AKI), 3320 (5.7%) had moderate to severe AKI, and 1018 (1.7%) required dialysis within 2 weeks of surgery. Female sex was associated with higher risk for AKI in models that were based on preoperative serum creatinine (OR, 1.35; 95% CI, 1.29-1.42), and lower risk with the use of estimated glomerular filtration, (OR, 0.90; 95% CI, 0.86-0.95). The risk for moderate to severe CS-AKI for a given immediate peri-operative change in serum creatinine was higher in female compared to male patients (p < .0001 and p < .0001 for non-linearity), and the association was modified by pre-operative kidney function (p < .0001 for interaction).

Conclusions

The association of patient sex with CS-AKI and its direction was dependent on the operational definition of pre-operative kidney function, and differential outcome misclassification due to AKI defined by absolute change in serum creatinine.

Overcoming biological barriers BBB/BBTB by designing PUFA functionalised lipid-based nanocarriers for glioblastoma targeted therapy

A major obstacle for chemotherapeutics in Glioblastoma (GB) is to reach the tumour cells due to the presence of the blood-brain barrier (BBB) and chemoresistance of anticancer drugs. The present study reports two polyunsaturated fatty acids, gamma-linolenic acid (GLA) and alpha-linolenic acid (ALA) appended nanostructured lipid carriers (NLCs) of a CNS negative chemotherapeutic drug docetaxel (DTX) for targeted delivery to GB. The ligand appended DTX-NLCs demonstrated particle size < 160 nm, PDI < 0.29 and a negative surface charge. The successful linkage of GLA (41 %) and ALA (30 %) ligand conjugation to DTX- NLCs was confirmed by diminished surface amino groups on the NLCs, lower surface charge and FTIR profiling. Fluorophore labelled GLA-DTX-NLCs and ALA-DTX-NLCs permeated the in-vitro 3D BBB model with Papp values of 1.8 × 10-3 and 1.9 × 10-3 cm/s respectively. Following permeation, both formulations showed enhanced uptake by GB immortalised cells while ALA-DTX-NLCs showed higher uptake in patient-derived GB cells as evidenced in an in-vitro 3D blood brain tumour barrier (BBTB) model. Both surface functionalised formulations showed higher internalisation in GB cells as compared to bare DTX-NLCs. ALA-DTX-NLCs and GLA-DTX-NLCs showed 13.9-fold and 6.8-fold higher DTX activity respectively at 24 h as indicated by IC50 values when tested in patient-derived GB cells. ALA-DTX-NLCs displayed better efficacy than GLA-DTX-NLCs when tested against 3D tumour spheroids and patient-derived cells. These novel formulations will contribute widely to overcoming biological barriers for treating glioblastoma.

Thrombosis with thrombocytopenia syndrome (TTS) following adenovirus vector COVID-19 vaccination in Canada

INTRODUCTION

Identifying and monitoring adverse events following vaccination contributed to the safety and effectiveness of COVID-19 mass vaccination campaigns. In March 2021, international reports emerged of an adverse event following vaccination with adenovirus vector COVID-19 vaccines (ChAdOx1-S [recombinant] and Ad26.COV2.S) of thrombosis with low platelet counts, referred to as thrombosis with thrombocytopenia syndrome (TTS). We described TTS reports in Canada following adenovirus vector COVID-19 vaccines and investigated whether the observed number of events were higher than expected.

METHODS

Reports of TTS following receipt of ChAdOx1-S [recombinant] or Ad26.COV2.S meeting the Canadian case definition for TTS and diagnostic certainty levels 1-3 of the Brighton Collaboration case definition, submitted to the Canadian Adverse Events Following Immunization Surveillance System and Canada Vigilance Database between February 26, 2021 and October 31, 2022 were included. Demographics and characteristics of the TTS reports are described along with an analysis comparing the observed number of reports to the expected number.

RESULTS

As of October 31, 2022, 56 reports of TTS following administration of ChAdOx1-S [recombinant] and no reports following Ad26.COV2.S vaccines were reported in Canada, of which 37 had functionally positive anti-PF4 antibodies. The median age was 56 years; males accounted for 54 % of reports. Five deaths were reported. The observed number of reports exceeded the expected for all ages and sexes combined, as well as for males aged 30-49 and 60-69 years, and females aged 40-59 years.

CONCLUSION

Based on international surveillance data, Canada evaluated a statistical signal of TTS following adenovirus vector vaccines. The investigation of this signal demonstrated how post-market vaccine safety surveillance systems were successful in investigating rare adverse events during the rollout of COVID-19 vaccines in Canada. As adenovirus vector vaccines continue to be administered, characterization of the association between the vaccine and TTS informs immunization programs and policies.

Intrapulmonary and Intracardiac Shunts in Adult COVID-19 Versus Non-COVID Acute Respiratory Distress Syndrome ICU Patients Using Echocardiography and Contrast Bubble Studies (COVID-Shunt Study): A Prospective, Observational Cohort Study

OBJECTIVES

Studies have suggested intrapulmonary shunts may contribute to hypoxemia in COVID-19 acute respiratory distress syndrome (ARDS) with worse associated outcomes. We evaluated the presence of right-to-left (R-L) shunts in COVID-19 and non-COVID ARDS patients using a comprehensive hypoxemia workup for shunt etiology and associations with mortality.

DESIGN

Prospective, observational cohort study.

SETTING

Four tertiary hospitals in Edmonton, Alberta, Canada.

PATIENTS

Adult critically ill, mechanically ventilated, ICU patients admitted with COVID-19 or non-COVID (November 16, 2020, to September 1, 2021).

INTERVENTIONS

Agitated-saline bubble studies with transthoracic echocardiography/transcranial Doppler ± transesophageal echocardiography assessed for R-L shunts presence.

MEASUREMENTS AND MAIN RESULTS

Primary outcomes were shunt frequency and association with hospital mortality. Logistic regression analysis was used for adjustment. The study enrolled 226 patients (182 COVID-19 vs 42 non-COVID). Median age was 58 years (interquartile range [IQR], 47-67 yr) and Acute Physiology and Chronic Health Evaluation II scores of 30 (IQR, 21-36). In COVID-19 patients, the frequency of R-L shunt was 31 of 182 COVID patients (17.0%) versus 10 of 44 non-COVID patients (22.7%), with no difference detected in shunt rates (risk difference [RD], -5.7%; 95% CI, -18.4 to 7.0; p = 0.38). In the COVID-19 group, hospital mortality was higher for those with R-L shunt compared with those without (54.8% vs 35.8%; RD, 19.0%; 95% CI, 0.1-37.9; p = 0.05). This did not persist at 90-day mortality nor after adjustment with regression.

CONCLUSIONS

There was no evidence of increased R-L shunt rates in COVID-19 compared with non-COVID controls. R-L shunt was associated with increased in-hospital mortality for COVID-19 patients, but this did not persist at 90-day mortality or after adjusting using logistic regression.

Bioequivalence Studies of Sildenafil Citrate Orodispersible Film Administered with and without Water vs ViagraⓇ Film-Coated Tablets in Healthy Male Volunteers

Background

Orodispersible film (ODF) formulation offers ease of use, convenience of administration, and other advantages, especially for patients who have difficulty in swallowing or are on liquid restriction compared with conventional oral formulations for the treatment of erectile dysfunction.

Objectives

These studies compared the bioequivalence of 50 mg sildenafil citrate ODF formulation (test drug) with the marketed 50 mg sildenafil citrate film-coated tablet (FCT) (Viagra^Ⓡ; Pfizer, New York, NY) (reference drug), with and without water in 2 randomized cross-over studies.

Methods

Two randomized cross-over studies were conducted. The first study explored the bioequivalence of test drug administered with and without water compared with the reference drug with water. The second study investigated the bioequivalence of test drug, without water, compared with the reference drug with water. Forty-two and 80 healthy male volunteers were recruited in the first and second study, respectively. All volunteers fasted for 10 hours pre-dose. A 1-day washout period between doses was observed. Blood samples were collected at both before (up to 120 minutes before dosing) and after dosing (at different intervals up to 14 hours) stages. Statistical analyses on pharmacokinetic parameters were performed. Safety and tolerability for both the formulations were evaluated.

Results

In the first study, bioequivalence was demonstrated for sildenafil citrate ODF administered with water when compared with the Viagra^Ⓡ FCT. The ratios of adjusted geometric means (90% confidence interval (CI)) were maximum plasma concentration: 1.02 (94.91-108.78) and area under the plasma concentration-time curve: 1.09 (104.49-113.21) for sildenafil citrate ODF administered with water vs Viagra^Ⓡ FCT. These ratios were within the bioequivalence acceptance range of 80% to 125%, indicating that the bioequivalence criteria were met. The pharmacokinetic parameters for the second study also showed bioequivalence for sildenafil citrate ODF (without water) compared with Viagra^Ⓡ FCT. The ratios of adjusted geometric means (90% CI) were maximum plasma concentration: 1.02 (95.47-109.36) and area under the plasma concentration-time curve: 1.06 (103.42-108.40) for sildenafil citrate ODF administered without water vs Viagra^Ⓡ FCT. Adverse events in both the studies occurred at similar rates for the 2 formulations and were mild in intensity.

Conclusions

These results suggest that the new ODF formulation can be used interchangeably with the marketed FCT formulation. Sildenafil citrate ODF administered with and without water met bioequivalence criteria compared with Viagra^Ⓡ FCT administered with water under fasted conditions in healthy adult male volunteers. The new ODF formulation can be used as a suitable alternative to the conventional oral solid dosage form.

Lumbar Discectomy With Bone-Anchored Annular Closure Device in Patients With Large Annular Defects: One-Year Results

BACKGROUND

Reherniation rates following lumbar discectomy are low for most patients; however, patients with a large defect in the annulus fibrosis have a significantly higher risk of recurrence. Previous results from a randomized controlled trial (RCT) demonstrated that the implantation of a bone-anchored annular closure device (ACD) during discectomy surgery lowered the risk of symptomatic reherniation and reoperation over one year with fewer serious adverse events (SAEs) compared to discectomy alone.

OBJECTIVE

The objective of this prospective, post-market, historically controlled study was to evaluate the use of an ACD during discectomy, and to confirm the results of the RCT that was used to establish regulatory approval in the United States.

METHODS

In this post-market study, all patients (N = 55) received discectomy surgery with a bone-anchored ACD. The comparison population was patients enrolled in the RCT study who had discectomy with an ACD (N = 262) or discectomy alone (N = 272). All other eligibility criteria, surgical technique, device characteristics, and follow-up methodology were comparable between studies. Endpoints included rate of symptomatic reherniation or reoperation, SAEs, and patient-reported measures of disability, pain, and quality of life.

RESULTS

Fifty-five patients received ACD implants at 12 sites between May 2020 and February 2021. In the previous RCT, 272 control patients had discectomy surgery alone (RCT-Control), and 262 patients had discectomy surgery with an ACD implant (RCT-ACD). Baseline characteristics across groups were typical of the overall population undergoing lumbar discectomy. The proportion of patients who experienced reherniation and/or reoperation was significantly lower in the ACD group compared to RCT-ACD and RCT-Control groups (p < 0.05). In the ACD study, the one-year rate of symptomatic reherniation was 3.7%, compared to 8.5% in the RCT-ACD group and 17.0% in the RCT-Control group. In the ACD group, the risk of reoperation was 5.5%, compared to 6.5% in the RCT-ACD group and 12.5% in the RCT-Control group. There were no device-related SAEs or device integrity failures in the ACD, and there were clinically meaningful improvements in patient-reported measures of disability, pain, and quality of life.

CONCLUSION

In this post-market study of bone-anchored ACD in patients with large annular defects, rates of symptomatic reherniation, reoperation, and SAEs were all low. Compared to the RCT, the post-market ACD study demonstrated lower rates of reherniation and/or reoperation and measures of back pain one-year post-surgery.

Perioperative glycemic management in adults presenting for elective cardiac and non-cardiac surgery

Perioperative dysglycemia is associated with adverse outcomes in both cardiac and non-cardiac surgical patients. Hyperglycemia in the perioperative period is associated with an increased risk of postoperative infections, length of stay, and mortality. Hypoglycemia can induce neuronal damage, leading to significant cognitive deficits, as well as death. This review endeavors to summarize existing literature on perioperative dysglycemia and provides updates on pharmacotherapy and management of perioperative hyperglycemia and hypoglycemia in surgical patients.

A Randomized Trial of Autologous Chondrocyte Implantation Versus Alternative Forms of Surgical Cartilage Management in Patients With a Failed Primary Treatment for Chondral or Osteochondral Defects in the Knee

BACKGROUND

There are limited randomized controlled trials with long-term outcomes comparing autologous chondrocyte implantation (ACI) versus alternative forms of surgical cartilage management within the knee.

PURPOSE

To determine at 5 years after surgery whether ACI was superior to alternative forms of cartilage management in patients after a failed previous treatment for chondral or osteochondral defects in the knee.

STUDY DESIGN

Randomized controlled trial; Level of evidence, 1.

METHODS

In total, 390 participants were randomly assigned to receive either ACI or alternative management. Patients aged 18 to 55 years with one or two symptomatic cartilage defects who had failed 1 previous therapeutic surgical procedure in excess of 6 months prior were included. Dual primary outcome measures were used: (1) patient-completed Lysholm knee score and (2) time from surgery to cessation of treatment benefit. Secondary outcome measures included International Knee Documentation Committee and Cincinnati Knee Rating System scores, as well as number of serious adverse events. Analysis was performed on an intention-to-treat basis.

RESULTS

Lysholm scores were improved by 1 year in both groups (15.4 points [95% CI, 11.9 to 18.8] and 15.2 points [95% CI, 11.6 to 18.9]) for ACI and alternative, with this improvement sustained over the duration of the trial. However, no evidence of a difference was found between the groups at 5 years (2.9 points; 95% CI, -1.8 to 7.5; P = .46). Approximately half of the participants (55%; 95% CI, 47% to 64% with ACI) were still experiencing benefit at 5 years, with time to cessation of treatment benefit similar in both groups (hazard ratio, 0.97; 95% CI, 0.72 to 1.32; P > .99). There was a differential effect on Lysholm scores in patients without previous marrow stimulation compared with those with marrow stimulation (P = .03; 6.4 points in favor of ACI; 95% CI, -0.4 to 13.1). More participants experienced a serious adverse event with ACI (P = .02).

CONCLUSION

Over 5 years, there was no evidence of a difference in Lysholm scores between ACI and alternative management in patients who had previously failed treatment. Previous marrow stimulation had a detrimental effect on the outcome of ACI.

REGISTRATION

International Standard Randomised Controlled Trial Number: 48911177.

An external focus of attention enhances table tennis backhand stroke accuracy in low-skilled players

The aim of the study was to determine the impact of internal and external (proximal and distal) attentional focus on table tennis backhand stroke accuracy in low-skilled players. Fifty-one undergraduate physical education (PE) students were randomly assigned to 3 groups: Group G1 (IF) was instructed to focus on the hand holding the paddle, Group G2 (EFP) was instructed to focus on the ball, while Group G3 (EFD) was instructed to focus on targets marked on the tennis table. The experimental groups followed identical instructions except for the instruction about the focus of attention. Participants were asked to score as many points as possible by hitting the ball inside the three smallest targets marked on the tennis table. They were required to do so using a backhand stroke. The practice session consisted of 45 trials in three blocks of backhand (15 trials at each target). A special scoring system was used to determine the accuracy of the strokes. One of the most important findings from the current research was that groups with an external focus of attention revealed significant improvements in accuracy in the post-test, while the group with an internal focus of attention achieved low training effects. No significant difference was observed between G2 (EFP) and G3 (EFD) in the delayed retention test, which indicates that proximal and distal attentional focus had similar effects on table tennis backhand stroke accuracy in low-skilled players.

P-043 A RETROSPECTIVE OUTCOME REVIEW OF THE USE OF EGIS ACELLULAR DERMAL MATRIX DURING ABDOMINAL WALL RECONSTRUCTION

Aim

We aimed to demonstrate the relative safety profile of an established non-crosslinked porcine acellular dermal matrix (ADM) during abdominal wall reconstruction.

Material & Methods

Individual real-world safety data on specific mesh products are often lacking. With recent media scrutiny over the use of mesh, we sought to quantify outcomes and demonstrate the safety of a specific ADM (reference 1). A retrospective casenote-based outcome analysis was performed on patients who underwent mesh augmentation during abdominal wall reconstruction from two NHS institutions. Both elective and emergency patients were included from January 2018 to December 2021.

Results

Fifty-five patients were included in the study across two NHS specialist hernia centres. We identified a mean wound infection rate of 14.2% (range 2–22%) with a median follow up of 9 months (range 3–18 months). Hernia recurrence rate was 10.4% (range 5–22%). We found 7 patients (12%) developed a seroma, 1 of whom required seroma aspiration. Only 4 patients (7%) had post-operative dehiscence requiring further intervention, all of whom had Ventral Hernia Working Group (VHWG) Grade 3 or 4 wounds pre-operatively.

Conclusions

Our data supports the continued use of a widely available ADM for abdominal wall reconstruction in both elective and emergency cases, highlighting its positive relative safety profile.

Clinical characteristics with inflammation profiling of long COVID and association with 1-year recovery following hospitalisation in the UK: a prospective observational study

BACKGROUND

No effective pharmacological or non-pharmacological interventions exist for patients with long COVID. We aimed to describe recovery 1 year after hospital discharge for COVID-19, identify factors associated with patient-perceived recovery, and identify potential therapeutic targets by describing the underlying inflammatory profiles of the previously described recovery clusters at 5 months after hospital discharge.

METHODS

The Post-hospitalisation COVID-19 study (PHOSP-COVID) is a prospective, longitudinal cohort study recruiting adults (aged ≥18 years) discharged from hospital with COVID-19 across the UK. Recovery was assessed using patient-reported outcome measures, physical performance, and organ function at 5 months and 1 year after hospital discharge, and stratified by both patient-perceived recovery and recovery cluster. Hierarchical logistic regression modelling was performed for patient-perceived recovery at 1 year. Cluster analysis was done using the clustering large applications k-medoids approach using clinical outcomes at 5 months. Inflammatory protein profiling was analysed from plasma at the 5-month visit. This study is registered on the ISRCTN Registry, ISRCTN10980107, and recruitment is ongoing.

FINDINGS

2320 participants discharged from hospital between March 7, 2020, and April 18, 2021, were assessed at 5 months after discharge and 807 (32·7%) participants completed both the 5-month and 1-year visits. 279 (35·6%) of these 807 patients were women and 505 (64·4%) were men, with a mean age of 58·7 (SD 12·5) years, and 224 (27·8%) had received invasive mechanical ventilation (WHO class 7-9). The proportion of patients reporting full recovery was unchanged between 5 months (501 [25·5%] of 1965) and 1 year (232 [28·9%] of 804). Factors associated with being less likely to report full recovery at 1 year were female sex (odds ratio 0·68 [95% CI 0·46-0·99]), obesity (0·50 [0·34-0·74]) and invasive mechanical ventilation (0·42 [0·23-0·76]). Cluster analysis (n=1636) corroborated the previously reported four clusters: very severe, severe, moderate with cognitive impairment, and mild, relating to the severity of physical health, mental health, and cognitive impairment at 5 months. We found increased inflammatory mediators of tissue damage and repair in both the very severe and the moderate with cognitive impairment clusters compared with the mild cluster, including IL-6 concentration, which was increased in both comparisons (n=626 participants). We found a substantial deficit in median EQ-5D-5L utility index from before COVID-19 (retrospective assessment; 0·88 [IQR 0·74-1·00]), at 5 months (0·74 [0·64-0·88]) to 1 year (0·75 [0·62-0·88]), with minimal improvements across all outcome measures at 1 year after discharge in the whole cohort and within each of the four clusters.

INTERPRETATION

The sequelae of a hospital admission with COVID-19 were substantial 1 year after discharge across a range of health domains, with the minority in our cohort feeling fully recovered. Patient-perceived health-related quality of life was reduced at 1 year compared with before hospital admission. Systematic inflammation and obesity are potential treatable traits that warrant further investigation in clinical trials.

FUNDING

UK Research and Innovation and National Institute for Health Research.

Experiences of Multidisciplinary Working: Perspectives from the Wessex Ghana Stroke Partnership

INTRODUCTION

Substantial gaps remain in our understanding of stroke in Africa as well as in stroke care, practice and policy on the continent. The effective organization of preventative, therapeutic and rehabilitative stroke services continue to be challenging in many African countries.

METHODOLOGY

In this article we define the nature, function and benefits of effective multidisciplinary team (MDT) working. The experiences and perspectives of members of the MDT were collated by focus group discussions as well as individual and country specific contributions.

RESULTS

The experiences and perspectives of multidisciplinary team members from the United Kingdom and Ghana implementing these practices at the first stroke unit in Korle Bu Teaching Hospital, Accra, with a transparent discussion of successes and challenges faced throughout development of the service, is presented. MDT working has improved outcomes for patients and families who use the services, including encouraging better shared treatment planning and compliance. More stroke rehabilitation services are provided than previously, including greater self-management education and better secondary prevention care.

CONCLUSION

It is hoped that this article will provide an inspirational model for others working to provide stroke care in low-resource settings in Africa and worldwide.

Isolation and In vitro Culture of Bone Marrow-Derived Macrophages for the Study of NO-Redox Biology

Macrophages are derived from hematopoietic progenitor cells throughout the body, are central to inflammatory processes, and participate in innate and adaptive immune responses. In vitro study of macrophages can be undertaken by ex vivo culture from the peritoneum or through differentiation of myeloid bone marrow progenitor cells to form bone marrow-derived macrophages (BMDMs). A common approach to macrophage differentiation from precursors involves the use of conditioned media from L929 cells (LCM). This media is easy to self-produce but suffers from batch variability, and its constituents are undefined. Similarly, Foetal Bovine Serum (FBS) is used to support growth but contains a vast mixture of undefined molecules that may vary between batches. These methods are not adequate for the study of nitric oxide biology and redox mechanisms as they both contain substantial amounts of small molecules that either interfere with redox mechanisms or supplement levels of cofactors, such as tetrahydrobiopterin (BH4), required for the production of NO from inducible nitric oxide synthase (iNOS). In this report, we present an optimized protocol allowing for control of the NO-redox environment by reducing the levels of exogenous biopterin while maintaining conditions suitable for cell growth and differentiation. Tight control of culture media composition helps ensure experimental reproducibility and facilitates accurate interpretation of results. In this protocol, BMDMs were obtained from a GTP cyclohydrolase (GCH)- deficient mouse model. Culture of BMDMs was performed with media containing either (i) conditioned LCM, or (ii) recombinant M-CSF and GM-CSF to produce minimal artifacts while obtaining BH4 and NO-deficient culture conditions - thus allowing for the reproducible study of NO-redox biology and immunometabolism in vitro.

Exploring foot-and-mouth disease virus antibody interactions using biolayer interferometry

Foot-and-mouth disease virus (FMDV) vaccines protect animals from infection by inducing antibodies. The level of neutralising antibody induced in response to vaccination (or infection), as measured by a virus neutralisation test, is an important parameter with regards to the level of protection afforded against subsequent challenge. However, in addition to overall titre, antibody avidity also represents a crucial metric when assessing the protective efficacy of antibodies. In this project we investigated the use of biolayer interferometry (BLI) to measure the avidity of FMDV antibodies to FMDV antigens. Antibodies targeting site I of the FMDV particle were detected using a commercially synthesised biotinylated peptide. In contrast, the entire antigenic landscape of the FMDV particle was represented by biotinylated FMDV capsids. The antigens were loaded onto Octet streptavidin biosensors at an optimal concentration prior to dipping into antibodies. The sera from different animals varied in avidity, reflecting the quantitative differences in avidity that exist between individual animals in response to FMDV vaccines. Interestingly, the Kdis values obtained for site I vs the entire capsid were different, supporting the importance of other sites beyond site I. Similarly, monoclonal antibodies targeting distinct, known antigenic sites on the capsid surface also resulted in different avidities. The BLI methodology reported here offers a useful approach by which to investigate the strength of antibody interactions at specific sites. In conjunction with recombinant technology, BLI will help aid in investigations into the relative importance of the different antigenic sites with regards to inducing a protective response.

Predictive Accuracy of a Perioperative Laboratory Test-Based Prediction Model for Moderate to Severe Acute Kidney Injury After Cardiac Surgery

IMPORTANCE

Effective treatment of acute kidney injury (AKI) is predicated on timely diagnosis; however, the lag in the increase in serum creatinine levels after kidney injury may delay therapy initiation.

OBJECTIVE

To determine the derivation and validation of predictive models for AKI after cardiac surgery.

DESIGN, SETTING, AND PARTICIPANTS

Multivariable prediction models were derived based on a retrospective observational cohort of adult patients undergoing cardiac surgery between January 2000 and December 2019 from a US academic medical center (n = 58 526) and subsequently validated on an external cohort from 3 US community hospitals (n = 4734). The date of final follow-up was January 15, 2020.

EXPOSURES

Perioperative change in serum creatinine and postoperative blood urea nitrogen, serum sodium, potassium, bicarbonate, and albumin from the first metabolic panel after cardiac surgery.

MAIN OUTCOMES AND MEASURES

Area under the receiver-operating characteristic curve (AUC) and calibration measures for moderate to severe AKI, per Kidney Disease: Improving Global Outcomes (KDIGO), and AKI requiring dialysis prediction models within 72 hours and 14 days following surgery.

RESULTS

In a derivation cohort of 58 526 patients (median [IQR] age, 66 [56-74] years; 39 173 [67%] men; 51 503 [91%] White participants), the rates of moderate to severe AKI and AKIrequiring dialysis were 2674 (4.6%) and 868 (1.48%) within 72 hours and 3156 (5.4%) and 1018 (1.74%) within 14 days after surgery. The median (IQR) interval to first metabolic panel from conclusion of the surgical procedure was 10 (7-12) hours. In the derivation cohort, the metabolic panel-based models had excellent predictive discrimination for moderate to severe AKI within 72 hours (AUC, 0.876 [95% CI, 0.869-0.883]) and 14 days (AUC, 0.854 [95% CI, 0.850-0.861]) after the surgical procedure and for AKI requiring dialysis within 72 hours (AUC, 0.916 [95% CI, 0.907-0.926]) and 14 days (AUC, 0.900 [95% CI, 0.889-0.909]) after the surgical procedure. In the validation cohort of 4734 patients (median [IQR] age, 67 (60-74) years; 3361 [71%] men; 3977 [87%] White participants), the models for moderate to severe AKI after the surgical procedure showed AUCs of 0.860 (95% CI, 0.838-0.882) within 72 hours and 0.842 (95% CI, 0.820-0.865) within 14 days and the models for AKI requiring dialysis and 14 days had an AUC of 0.879 (95% CI, 0.840-0.918) within 72 hours and 0.873 (95% CI, 0.836-0.910) within 14 days after the surgical procedure. Calibration assessed by Spiegelhalter z test showed P >.05 indicating adequate calibration for both validation and derivation models.

CONCLUSIONS AND RELEVANCE

Among patients undergoing cardiac surgery, a prediction model based on perioperative basic metabolic panel laboratory values demonstrated good predictive accuracy for moderate to severe acute kidney injury within 72 hours and 14 days after the surgical procedure. Further research is needed to determine whether use of the risk prediction tool improves clinical outcomes.

Varicella Zoster Reactivation Causing Acute Retinal Necrosis following mRNA COVID-19 Vaccination in a Young Immunocompetent Man

BACKGROUND

Varicella zoster reactivation is an increasingly recognised event following mRNA COVID-19 vaccination. In addition, various ocular inflammatory and infectious adverse events following COVID-19 vaccination have been described in the literature. This case report describes acute retinal necrosis (ARN) secondary to varicella zoster virus (VZV) reactivation following COVID-19 mRNA vaccination.

CASE DESCRIPTION

A 42-year-old immunocompetent man developed left ARN 12 days following first dose of Pfizer BioNTech mRNA COVID-19 vaccination. Aqueous and vitreous tap polymerase chain reaction testing was positive for VZV. Good visual outcome was achieved with combination therapy, including intravitreal foscarnet, oral valaciclovir and prednisolone, topical dexamethasone and atropine, and barrier retinal laser. Second dose of the vaccine is planned under cover of high-dose oral valaciclovir therapy.

CONCLUSION

This case illustrates the possible association between COVID-19 vaccination and potentially blinding VZV reactivation. Therefore, prompt ophthalmic assessment is recommended in patients with visual disturbance following COVID-19 vaccination.

Mapping of a N-terminal α-helix domain required for human PINK1 stabilization, Serine228 autophosphorylation and activation in cells

Autosomal recessive mutations in the PINK1 gene are causal for Parkinson's disease (PD). PINK1 encodes a mitochondrial localized protein kinase that is a master-regulator of mitochondrial quality control pathways. Structural studies to date have elaborated the mechanism of how mutations located within the kinase domain disrupt PINK1 function; however, the molecular mechanism of PINK1 mutations located upstream and downstream of the kinase domain is unknown. We have employed mutagenesis studies to define the minimal region of human PINK1 required for optimal ubiquitin phosphorylation, beginning at residue Ile111. Inspection of the AlphaFold human PINK1 structure model predicts a conserved N-terminal α-helical extension (NTE) domain forming an intramolecular interaction with the C-terminal extension (CTE), which we corroborate using hydrogen/deuterium exchange mass spectrometry of recombinant insect PINK1 protein. Cell-based analysis of human PINK1 reveals that PD-associated mutations (e.g. Q126P), located within the NTE : CTE interface, markedly inhibit stabilization of PINK1; autophosphorylation at Serine228 (Ser228) and Ubiquitin Serine65 (Ser65) phosphorylation. Furthermore, we provide evidence that NTE and CTE domain mutants disrupt PINK1 stabilization at the mitochondrial Translocase of outer membrane complex. The clinical relevance of our findings is supported by the demonstration of defective stabilization and activation of endogenous PINK1 in human fibroblasts of a patient with early-onset PD due to homozygous PINK1 Q126P mutations. Overall, we define a functional role of the NTE : CTE interface towards PINK1 stabilization and activation and show that loss of NTE : CTE interactions is a major mechanism of PINK1-associated mutations linked to PD.

Fc-Mediated Functions of Porcine IgG Subclasses

The pig is an important agricultural species and powerful biomedical model. We have established the pig, a large natural host animal for influenza with many physiological similarities to humans, as a robust model for testing the therapeutic potential of monoclonal antibodies. Antibodies provide protection through neutralization and recruitment of innate effector functions through the Fc domain. However very little is known about the Fc-mediated functions of porcine IgG subclasses. We have generated 8 subclasses of two porcine monoclonal anti influenza hemagglutinin antibodies. We characterized their ability to activate complement, trigger cytotoxicity and phagocytosis by immune cells and assayed their binding to monocytes, macrophages, and natural killer cells. We show that IgG1, IgG2a, IgG2b, IgG2c and IgG4 bind well to targeted cell types and mediate complement mediated cellular cytotoxicity (CDCC), antibody dependent cellular cytotoxicity (ADCC) and antibody mediated cell phagocytosis (ADCP). IgG5b and IgG5c exhibited weak binding and variable and poor functional activity. Immune complexes of porcine IgG3 did not show any Fc-mediated functions except for binding to monocytes and macrophages and weak binding to NK cells. Interestingly, functionally similar porcine IgG subclasses clustered together in the genome. These novel findings will enhance the utility of the pig model for investigation of therapeutic antibodies.

Lumbar Discectomy With Barricaid Device Implantation in Patients at High Risk of Reherniation: Initial Results From a Postmarket Study

Background

Patients with large defects in the annulus fibrosus following lumbar discectomy have high rates of symptomatic reherniation and reoperation. An FDA randomized controlled trial (RCT) with a bone-anchored device (Barricaid, Intrinsic Therapeutics, Woburn, MA) that occludes the annular defect reported significantly lower risk of symptomatic reherniation and reoperation compared to patients receiving discectomy only. However, results of the Barricaid device in real-world use remain limited. 

Methods

This was a post-market study to determine the real-world outcomes of the Barricaid device when used in addition to primary lumbar discectomy in patients with large annular defects. Main outcomes included leg pain severity, Oswestry Disability Index (ODI), adverse events, symptomatic reherniation, and reoperation. Imaging studies were read by an independent imaging core laboratory. This paper reports the initial three-month primary endpoint results from the trial; one-year patient follow-up is ongoing.

Results

Among 55 patients (mean age 41±13 years, 60% male), the mean percent reduction in leg pain severity was 92%, and the mean percent reduction in ODI score was 79%. The three-month rate of symptomatic reherniation was 3.6% and the rate of reoperation was 1.8%. The serious adverse event rate was 5.5%; no device migrations or fractures were observed. 

Conclusion

Among patients with large annular defects following lumbar discectomy treated with the Barricaid device in real-world conditions, early results demonstrated clinically meaningful improvements in patient symptoms and low rates of symptomatic reherniation, reoperation, and complications, which were comparable to those observed with the device in an FDA-regulated trial.

748 Case Series: Experience of Using External Fixation as An Adjunct in The Management of MRONJ Affecting the Mandible

Introduction

External fixation was first described by Malgaigne and Rigaud in 1870 for use on long bones, then adapted for OMFS in 1934 and used for treating comminuted fractures. In recent times, popularity of external fixators has decreased with the use of mini-plates, often only used in major trauma, for example gunshot wounds. This is a case series of patients who have been treated by external fixation for medication related osteonecrosis (MRONJ) of the jaw and could be a fairly simple alternative to major reconstructive surgery in such cases. This method of treatment has been particularly useful during the Covid-19 pandemic as a non-aerosol generating procedure.

Method

A single centre, retrospective study of 5 cases between December 2018 - December 2020. The MRONJ cases were graded using the AAOMS classification. All cases treated with external fixation of mandible were included. Pre-operative condition, medical history, treatment complications, pain management, length of treatment and follow-up results were recorded.

Results

Of the 5 cases treated for MRONJ, 4 of these had pathological fractures. All were AAOMS stage 3. The mean duration of treatment was 78 days, with regular clinical reviews monitoring progress. Of these cases, 4 cases healed well with significant improvement or closure of intraoral and extra-oral wounds.

Conclusions

In this small case series the technique has shown positive results; being well received by patients and allowing function while in situ. It allows treatment of pathological fractures as well as stabilising the mandible as a preventative measure whilst debriding severely atrophic mandibles.

Differential cell counts using center-point networks achieves human-level accuracy and efficiency over segmentation

Differential cell counts is a challenging task when applying computer vision algorithms to pathology. Existing approaches to train cell recognition require high availability of multi-class segmentation and/or bounding box annotations and suffer in performance when objects are tightly clustered. We present differential count network ("DCNet"), an annotation efficient modality that utilises keypoint detection to locate in brightfield images the centre points of cells (not nuclei) and their cell class. The single centre point annotation for DCNet lowered burden for experts to generate ground truth data by 77.1% compared to bounding box labeling. Yet centre point annotation still enabled high accuracy when training DCNet on a multi-class algorithm on whole cell features, matching human experts in all 5 object classes in average precision and outperforming humans in consistency. The efficacy and efficiency of the DCNet end-to-end system represents a significant progress toward an open source, fully computationally approach to differential cell count based diagnosis that can be adapted to any pathology need.

A pharmacokinetics study of proposed bevacizumab biosimilar MYL-1402O vs EU-bevacizumab and US-bevacizumab

PURPOSE

Bevacizumab is a recombinant humanized monoclonal antibody that inhibits vascular endothelial growth factor-specific angiogenesis in some cancers. MYL-1402O is a proposed bevacizumab biosimilar.

METHODS

The primary objective of this single-center, randomized, double-blind, three-arm, parallel-group, phase 1 study in healthy male volunteers was to evaluate bioequivalence of MYL-1402O to EU and US-reference bevacizumab, and EU-reference bevacizumab to US-reference bevacizumab. The primary pharmacokinetic parameter was area under the serum concentration-time curve from 0 extrapolated to infinity (AUC_0-∞). Pharmacokinetic parameters were analyzed using general linear models of analysis of variance. Secondary endpoints included safety and tolerability.

RESULTS

Of 111 enrolled subjects, 110 were included in the pharmacokinetic analysis (MYL-1402O, n = 37; EU-reference bevacizumab, n = 36; US-reference bevacizumab, n = 37). Bioequivalence was demonstrated between MYL-1402O and EU-reference bevacizumab, MYL-1402O and US-reference bevacizumab, and between EU- and US-reference bevacizumab where least squares mean ratios of AUC_0-∞ were close to 1, and 90% CIs were within the equivalence range (0.80-1.25). Secondary pharmacokinetic parameters (AUC from 0 to time of last quantifiable concentration [AUC_0-t], peak serum concentration [C_max], time to C_max, elimination rate constant, and elimination half-life) were also comparable, with 90% CIs for ratios of AUC_0-t and C_max within 80-125%. Treatment-emergent adverse events were similar across all three treatment groups and were consistent with clinical data for bevacizumab.

CONCLUSION

MYL-1402O was well tolerated and demonstrated pharmacokinetic and safety profiles similar to EU-reference bevacizumab and US-reference bevacizumab in healthy male volunteers. No new significant safety issues emerged (ClinicalTrials.gov, NCT02469987; ClinicalTrialsRegister.eu EudraCT, 2014-005621-12; June 12, 2015).

Deep learning-based point-scanning super-resolution imaging

Point-scanning imaging systems are among the most widely used tools for high-resolution cellular and tissue imaging, benefiting from arbitrarily defined pixel sizes. The resolution, speed, sample preservation and signal-to-noise ratio (SNR) of point-scanning systems are difficult to optimize simultaneously. We show these limitations can be mitigated via the use of deep learning-based supersampling of undersampled images acquired on a point-scanning system, which we term point-scanning super-resolution (PSSR) imaging. We designed a 'crappifier' that computationally degrades high SNR, high-pixel resolution ground truth images to simulate low SNR, low-resolution counterparts for training PSSR models that can restore real-world undersampled images. For high spatiotemporal resolution fluorescence time-lapse data, we developed a 'multi-frame' PSSR approach that uses information in adjacent frames to improve model predictions. PSSR facilitates point-scanning image acquisition with otherwise unattainable resolution, speed and sensitivity. All the training data, models and code for PSSR are publicly available at 3DEM.org.

Continuous-flow electrocoagulation (EC) process for iron removal from water: Experimental, statistical and economic study

The process of Electrocoagulation (EC), the in-situ production of coagulants by passing an electric current through sacrificial electrodes, is free of chemical additives and cost-effective. This makes it the most widely used water and wastewater treatment method. However, the literature highlights some significant drawbacks of this method including EC unit design limitations. This research therefore aimed to develop a new EC unit design using drilled plates (electrodes) to mix the solution being treated without using external mixers, this minimising power consumption. The performance of the new EC unit was validated by applying it to remove iron from water taking into account the effects of applied current density (ACD), the pH of the water (PoW), iron concentration (IC) and treatment time (TT). The effects of these parameters were optimised using the Box-Behnken model. Synthetic water samples containing different concentrations of iron (10-30 mg/l), were treated in a continuous flow, using the new EC reactor at different ACD (1.5-4.5 mA/cm²), PoW (4-10) and TT (10-50 min). The results revealed that the removal of 99.9% of iron was achieved by keeping PoW, ACD, IC and TT at 7, 3 mA/cm², 10 mg/l and 50 min, respectively. The effects of ACD, POW, IC and TT on iron removal could be successfully simulated with R² = 0.9788. The cost of removing iron using the proposed EC unit was 0.623 £/m³.

The morphology of the Late Pleistocene hominin remains from the site of La Cotte de St Brelade, Jersey (Channel Islands)

Thirteen permanent fully erupted teeth were excavated at the Paleolithic site of La Cotte de St Brelade in Jersey in 1910 and 1911. These were all found in the same location, on a ledge behind a hearth in a Mousterian occupation level. They were originally identified as being Neanderthal. A fragment of occipital bone was found in a separate locality in a later season. Recent dating of adjacent sediments gives a probable age of <48 ka. The purpose of this article is to provide an updated description of the morphology of this material and consider its likely taxonomic assignment from comparison with Neanderthal and Homo sapiens samples. One of the original teeth has been lost, and we identify one as nonhominin. At least two adult individuals are represented. Cervix shape and the absence of common Neanderthal traits in several teeth suggest affinities with H. sapiens in both individuals, while crown and root dimensions and root morphology of all the teeth are entirely consistent with a Neanderthal attribution, pointing toward a possible shared Neanderthal and H. sapiens ancestry (the likely date of this material corresponds with the time in which both Neanderthals and H. sapiens were present in Europe). The occipital fragment is stratigraphically more recent and does not exhibit any diagnostic Neanderthal features.

Coastal sea level anomalies and associated trends from Jason satellite altimetry over 2002-2018

Climate-related sea level changes in the world coastal zones result from the superposition of the global mean rise due to ocean warming and land ice melt, regional changes caused by non-uniform ocean thermal expansion and salinity changes, and by the solid Earth response to current water mass redistribution and associated gravity change, plus small-scale coastal processes (e.g., shelf currents, wind & waves changes, fresh water input from rivers, etc.). So far, satellite altimetry has provided global gridded sea level time series up to 10-15 km to the coast only, preventing estimation of sea level changes very close to the coast. Here we present a 16-year-long (June 2002 to May 2018), high-resolution (20-Hz), along-track sea level dataset at monthly interval, together with associated sea level trends, at 429 coastal sites in six regions (Northeast Atlantic, Mediterranean Sea, Western Africa, North Indian Ocean, Southeast Asia and Australia). This new coastal sea level product is based on complete reprocessing of raw radar altimetry waveforms from the Jason-1, Jason-2 and Jason-3 missions.

The application of life cycle assessment (LCA) to wastewater treatment: A best practice guide and critical review

Life cycle assessment (LCA) has been widely applied in the wastewater industry, but inconsistencies in assumptions and methods have made it difficult for researchers and practitioners to synthesize results from across studies. This paper presents a critical review of published LCAs related to municipal wastewater management with a focus on developing systematic guidance for researchers and practitioners to conduct LCA studies to inform planning, design, and optimization of wastewater management and infrastructure (wastewater treatment plants, WWTPs; collection and reuse systems; related treatment technologies and policies), and to support the development of new technologies to advance treatment objectives and the sustainability of wastewater management. The paper guides the reader step by step through LCA methodology to make informed decisions on i) the definition of the goal and scope, ii) the selection of the functional unit and system boundaries, iii) the selection of variables to include and their sources to obtain inventories, iv) the selection of impact assessment methods, and v) the selection of an effective approach for data interpretation and communication to decision-makers.

Artists on the edge of the world: An integrated approach to the study of Magdalenian engraved stone plaquettes from Jersey (Channel Islands)

The Upper Palaeolithic is characterised by the appearance of iconographic expressions most often depicting animals, including anthropomorphic forms, and geometric signs. The Late Upper Palaeolithic Magdalenian saw a flourishing of such depictions, encompassing cave art, engraving of stone, bone and antler blanks and decoration of tools and weapons. Though Magdalenian settlement exists as far northwest as Britain, there is a limited range of art known from this region, possibly associated with only fleeting occupation of Britain during this period. Stone plaquettes, flat fragments of stone engraved on at least one surface, have been found in large quantities at numerous sites spanning the temporal and geographical spread of the Magdalenian, but they have been absent so far from the archaeological record of the British Isles. Between 2015 and 2018, ten fragments of stone plaquettes extensively engraved with abstract designs were uncovered at the Magdalenian site of Les Varines, Jersey, Channel Islands. In this paper, we report detailed analyses of these finds, which provide new evidence for technologies of abstract mark-making, and their significance within the lives of people on the edge of the Magdalenian world. These engraved stone fragments represent important, rare evidence of artistic expression in what is the far northern and western range of the Magdalenian and add new insight to the wider significance of dynamic practices of artistic expression during the Upper Palaeolithic.

Isolation and culture of murine bone marrow-derived macrophages for nitric oxide and redox biology

Macrophages are mononuclear phagocytes derived from haematopoietic progenitors that are widely distributed throughout the body. These cells participate in both innate and adaptive immune responses and lie central to the processes of inflammation, development, and homeostasis. Macrophage physiology varies depending on the environment in which they reside and they exhibit rapid functional adaption in response to external stimuli. To study macrophages in vitro, cells are typically cultured ex vivo from the peritoneum or alveoli, or differentiated from myeloid bone marrow progenitor cells to form bone marrow-derived macrophages (BMDMs). BMDMs represent an efficient and cost-effective means of studying macrophage biology. However, the inherent sensitivity of macrophages to biochemical stimuli (such as cytokines, metabolic intermediates, and RNS/ROS) makes it imperative to control experimental conditions rigorously. Therefore, the aim of this study was to establish an optimised and standardised method for the isolation and culture of BMDMs. We used classically activated macrophages isolated from WT and nitric oxide (NO)-deficient mice to develop a standardised culture method, whereby the constituents of the culture media are defined. We then methodically compared our standardised protocol to the most commonly used method of BMDM culture to establish an optimal protocol for the study of nitric oxide (NO)-redox biology and immunometabolism in vitro.

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.

Understanding and optimising patient and public involvement in trial oversight: an ethnographic study of eight clinical trials

BACKGROUND

Trial oversight is important for trial governance and conduct. Patients and/or lay members of the public are increasingly included in trial oversight committees, influenced by international patient and public involvement (PPI) initiatives to improve the quality and relevance of research. However, there is a lack of guidance on how to undertake PPI in trial oversight and tokenistic PPI remains an issue. This paper explores how PPI functions in existing trial oversight committees and provides recommendations to optimise PPI in future trials. This was part of a larger study investigating the role and function of oversight committees in trials facing challenges.

METHODS

Using an ethnographic study design, we observed oversight meetings of eight UK trials and conducted semi-structured interviews with members of their trial steering committees (TSCs) and trial management groups (TMGs) including public contributors, trial sponsors and funders. Thematic analysis of data was undertaken, with findings integrated to provide a multi-perspective account of how PPI functions in trial oversight.

RESULTS

Eight TSC and six TMG meetings from eight trials were observed, and 66 semi-structured interviews conducted with 52 purposively sampled oversight group members, including three public contributors. PPI was reported as beneficial in trial oversight, with public members contributing a patient voice and fulfilling a patient advocacy role. However, public contributors were not always active at oversight meetings and were sometimes felt to have a tokenistic role, with trialists reporting a lack of understanding of how to undertake PPI in trial oversight. To optimise PPI in trial oversight, the following areas were highlighted: the importance of planning effective strategies to recruit public contributors; considering the level of oversight and stage(s) of trial to include PPI; support for public contributors by the trial team between and during oversight meetings.

CONCLUSIONS

We present evidence-based recommendations to inform future PPI in trial oversight. Consideration should be given at trial design stage on how to recruit and involve public contributors within trial oversight, as well as support and mentorship for both public contributors and trialists (in how to undertake PPI effectively). Findings from this study further strengthen the evidence base on facilitating meaningful PPI within clinical trials.

A proteomic signature for CNS adaptations to the valence of environmental stimulation

Environmental Enrichment leads to a significant improvement in long-term performance across a range of cognitive functions in mammals and it has been shown to produce an increased synaptic density and neurogenesis. Nevertheless it is still an open question as to whether some key aspects of spatial learning & memory and procedural learning might be embodied by different molecular pathways to those of social cognition. Associated with synaptic changes and potentially underlying conditions, the Ras-ERK pathway has been proposed to be the primary mediator of in vivo adaptations to environmental enrichment, acting via the downstream Ras-ERK signalling kinase MSK1 and the transcription factor CREB. Herein, we show that valence of environmental stimulation increased social competition and that this is associated with a specific proteomic signature in the frontal lobe but notably not in the hippocampus. Specifically, we show that altering the valence of environmental stimuli affected the level of social competition, with mice from negatively enriched environments winning significantly more encounters-even though mice from positive were bigger and should display dominance. This behavioural phenotype was accompanied by changes in the proteome of the fronto-ventral pole of the brain, with a differential increase in the relative abundance of proteins involved in the mitochondrial metabolic processes of the TCA cycle and respiratory processes. Investigation of this proteomic signature may pave the way for the elucidation of novel pathways underpinning the behavioural changes caused by negative enrichment and further out understanding of conditions whose core feature is increased social competition.

Survey of full-scale sidestream enhanced biological phosphorus removal (S2EBPR) systems and comparison with conventional EBPRs in North America: Process stability, kinetics, and microbial populations

Sidestream EBPR (S2EBPR) is an emerging alternative process to address common challenges in EBPR related to weak wastewater influent and may improve EBPR process stability. A systematic evaluation and comparison of the process performance and microbial community structure was conducted between conventional and S2EBPR facilities in North America. The statistical analysis suggested higher performance stability in S2EBPR than conventional EBPR, although possible bias associated with other plant-specific factors might have affected the comparison. Variations in stoichiometric values related to EBPR activity and discrepancies between the observed values and current model predictions suggested a varying degree of metabolic versatility of PAOs in S2EBPR systems that warrant further investigation. Microbial community analysis using various techniques suggested comparable known candidate PAO relative abundances in S2EBPR and conventional EBPR systems, whereas the relative abundance of known candidate GAOs seemed to be consistently lower in S2EBPR facilities than conventional EBPR facilities. 16S rRNA gene sequencing analysis revealed differences in the community phylogenetic fingerprints between S2EBPR and conventional facilities and indicated statistically higher microbial diversity index values in S2EBPR facilities than those in conventional EBPRs. PRACTITIONER POINTS: Sidestream EBPR (S2EBPR) can be implemented with varying and flexible configurations, and they offer advantages over conventional configurations for addressing the common challenges in EBPR related to weak wastewater influent and may improve EBPR process stability. Survey of S2EBPR plants in North America suggested statistically more stable phosphorus removal performance in S2EBPR plants than conventional EBPRs, although possible bias might affect the comparison due to other plant-specific factors. The EBPR kinetics and stoichiometry of the S2EBPR facilities seemed to vary and are associated with metabolic versatility of PAOs in S2EBPR systems that warrant further investigation. The abundance of known candidate PAOs in S2EBPR plants was similar to those in conventional EBPRs, and the abundance of known candidate GAOs was generally lower in S2EBPR than conventional EBPR facilities. Further finer-resolution analysis of PAOs and GAOs, as well as identification of other unknown PAOs and GAOs, is needed. Microbial diversity is higher in S2EBPR facilities compared with conventional ones, implying that S2EBPR microbial communities could show better resilience to perturbations due to potential functional redundancy.

Ex vivo specimen MRI and pathology confirm a rectosigmoid mesenteric waist at the junction of the mesorectum and mesocolon

AIM

Continuity of the mesentery has recently been established and may provide an anatomical basis for optimal colorectal resectional surgery. Preliminary data from operative specimen measurements suggest there is a tapering in the mesentery of the distal sigmoid. A mesenteric waist in this area may be a risk factor for local recurrence of colorectal cancer. This study aimed to investigate the anatomical characteristics of the mesentery at the colorectal junction.

METHOD

In this cross-sectional study, 20 patients were recruited. After planned colorectal resection, the surgical specimens were scanned in a MRI system and subsequently dissected and photographed as per national pathology guidelines. Mesenteric surface area and linear measurements were compared between MRI and pathology to establish the presence and location of a mesenteric waist.

RESULTS

Specimen analysis confirmed that a narrowing in the mesenteric surface area was consistently apparent at the rectosigmoid junction. Above the anterior peritoneal reflection, the surface area and posterior distance of the mesentery of the upper rectum initially decreased before increasing as the mesentery of the sigmoid colon. These anatomical properties created the appearance of a mesenteric 'waist' at the rectosigmoid junction. Using the anterior reflection as a reference landmark, the rectosigmoid waist occurred at a mean height of 23.6 and 21.7 mm on MRI and pathology, respectively.

CONCLUSION

A rectosigmoid waist occurs at the junction of the mesorectum and mesocolon, and is a mesenteric landmark for the rectum that is present on both radiology and pathology.

Chronic Dyrk1 Inhibition Delays the Onset of AD-Like Pathology in 3xTg-AD Mice

There is a critical need for new treatment approaches that can slow or prevent the progression of Alzheimer's disease (AD). Targets that act simultaneously on multiple relevant pathways could have significant therapeutic potential. Dual-specificity tyrosine phosphorylation-regulated kinase 1A (Dyrk1a) phosphorylates both amyloid precursor protein (APP) and tau. Dyrk1a is upregulated in post-mortem brains of AD patients, and such elevated expression is associated with cognitive deficits. We previously demonstrated that small molecule inhibition of Dyrk1 is well-tolerated and reduces amyloid plaques and pathological forms of tau in 3xTg-AD mice if administered after formation of these pathologies. However, while insoluble forms of hyperphosphorylated tau were reduced by Dyrk1 inhibition, overt neurofibrillary tangle (NFT) pathology remained unchanged. Herein, we specifically test the hypothesis that inhibition of Dyrk1 prior to NFT formation will delay the onset of pathology. 3xTg-AD mice were treated chronically, beginning at 6 months of age, prior to NFT pathology. Mice were dosed daily for either 3 or 6 months and amyloid and tau pathology were assessed. We show that chronic Dyrk1 inhibition reduces insoluble forms of amyloid beta peptides (Aβ) and hyper-phosphorylated tau long-term and that these reductions are associated with dramatic delay in the onset of both amyloid plaques and NFTs. In addition, we show that DYR219, a potent and selective small molecule Dyrk1 inhibitor, induces degradation of Dyrk1a protein, likely contributing to the efficacy of this small molecule approach in vivo. Collectively, these results suggest that therapeutic strategies targeting tau phosphorylation will show the greatest effect if administered very early in the pathogenesis of AD.