Control of Helicobacter pylori with engineered probiotics secreting selective guided antimicrobial peptides

Helicobacter pylori is the primary cause of 78% of gastric cancer cases, providing an opportunity to prevent cancer by controlling a single bacterial pathogen within the complex gastric microbiota. We developed highly selective antimicrobial agents against H. pylori by fusing an H. pylori-binding guide peptide (MM1) to broad-spectrum antimicrobial peptides. The common dairy probiotic Lactococcus lactis was then engineered to secrete these guided antimicrobial peptides (gAMPs). When co-cultured in vitro with H. pylori, the gAMP probiotics lost no toxicity compared to unguided AMP probiotics against the target, H. pylori, while losing >90% of their toxicity against two tested off-target bacteria. To test binding to H. pylori, the MM1 guide was fused to green fluorescent protein (GFP), resulting in enhanced binding compared to unguided GFP as measured by flow cytometry. In contrast, MM1-GFP showed no increased binding over GFP against five different off-target bacteria. These highly selective gAMP probiotics were then tested by oral gavage in mice infected with H. pylori. As a therapy, the probiotics outperformed antibiotic treatment, effectively eliminating H. pylori in just 5 days, and also protected mice from challenge infection as a prophylactic. As expected, the gAMP probiotics were as toxic against H. pylori as the unguided AMP probiotics. However, a strong rebound in gastric species diversity was found with both the selective gAMP probiotics and the non-selective AMP probiotics. Eliminating the extreme microbial dysbiosis caused by H. pylori appeared to be the major factor in diversity recovery. IMPORTANCE Alternatives to antibiotics in the control of Helicobacter pylori and the prevention of gastric cancer are needed. The high prevalence of H. pylori in the human population, the induction of microbial dysbiosis by antibiotics, and increasing antibiotic resistance call for a more sustainable approach. By selectively eliminating the pathogen and retaining the commensal community, H. pylori control may be achieved without adverse health outcomes. Antibiotics are typically used as a therapeutic post-infection, but a more targeted, less disruptive approach could be used as a long-term prophylactic against H. pylori or, by extension, against other gastrointestinal pathogens. Furthermore, the modular nature of the guided antimicrobial peptide (gAMP) technology allows for the substitution of different guides for different pathogens and the use of a cocktail of gAMPs to avoid the development of pathogen resistance.

Long-Term Follow-up of Multinodular and Vacuolating Neuronal Tumors and Implications for Surveillance Imaging

BACKGROUND AND PURPOSE

Most multinodular and vacuolating neuronal tumors (MVNTs) are diagnosed and followed radiologically without any change across time. There are no surveillance guidelines or quantitative volumetric assessments of these tumors. We evaluated MVNT volumes during long follow-up periods using segmentation tools with the aim of quantitative assessment.

MATERIALS AND METHODS

All patients with MVNTs in a brain MR imaging report in our system were reviewed. Patients with only 1 brain MR imaging or in whom MVNT was not clearly the most likely diagnosis were excluded. All MVNTs were manually segmented. For all follow-up examinations, absolute and percentage volume change from immediately prior and initial examinations were calculated.

RESULTS

Forty-eight patients (32 women; median age, 50.5 years at first scanning) underwent 158 brain MRIs. The median duration between the first and last scan was 15.6 months (interquartile range, 5.7-29.6 months; maximum, 6.4 years) and between consecutive scans, it was 6.7 months (interquartile range, 3.3-12.4 months; maximum, 4.9 years). Pearson correlation coefficients between days since immediately prior scan versus absolute and percentage volume change from immediately prior scan were r = 0.05 (P = .60) and r = 0.07 (P = .45), respectively. For the relationship between days since the first scan versus absolute and percentage volume change from the first scan, values were r = -0.06 (P = .53) and r = -0.04 (P = .67), respectively.

CONCLUSIONS

MVNT segmentation across follow-up brain MR imaging examinations did not demonstrate significant volume differences, suggesting that these tumors do not enlarge with time. Hence, frequent surveillance imaging of newly diagnosed MVNTs may not be necessary.

Genetic Determinants of Acinetobacter baumannii Serum-Associated Adaptive Efflux-Mediated Antibiotic Resistance

Acinetobacter baumannii is a nosocomial pathogen of serious healthcare concern that is becoming increasingly difficult to treat due to antibiotic treatment failure. Recent studies have revealed that clinically defined antibiotic-susceptible strains upregulate the expression of a repertoire of putative drug efflux pumps during their growth under biologically relevant conditions, e.g., in human serum, resulting in efflux-associated resistance to physiologically achievable antibiotic levels within a patient. This phenomenon, termed Adaptive Efflux Mediated Resistance (AEMR), has been hypothesized to account for one mechanism by which antibiotic-susceptible A. baumannii fails to respond to antibiotic treatment. In the current study, we sought to identify genetic determinants that contribute to A. baumannii serum-associated AEMR by screening a transposon mutant library for members that display a loss of the AEMR phenotype. Results revealed that mutation of a putative pirin-like protein, YhaK, results in a loss of AEMR, a phenotype that could be complemented by a wild-type copy of the yhaK gene and was verified in a second strain background. Ethidium bromide efflux assays confirmed that the loss of AEMR phenotype due to pirin-like protein mutation correlated with reduced overarching efflux capacity. Further, flow cytometry and confocal microscopy measures of a fluorophore 7-(dimethylamino)-coumarin-4-acetic acid (DMACA)-tagged levofloxacin isomer, ofloxacin, further verified that YhaK mutation reduces AEMR-mediated antibiotic efflux. RNA-sequencing studies revealed that YhaK may be required for the expression of multiple efflux-associated systems, including MATE and ABC families of efflux pumps. Collectively, the data indicate that the A. baumannii YhaK pirin-like protein plays a role in modulating the organism's adaptive efflux-mediated resistance phenotype.

The effect of long-term spaceflight on drug potency and the risk of medication failure

Pharmaceuticals selected for exploration space missions must remain stable and effective throughout mission timeframes. Although there have been six spaceflight drug stability studies, there has not been a comprehensive analytical analysis of these data. We sought to use these studies to quantify the rate of spaceflight drug degradation and the time-dependent probability of drug failure resulting from the loss of active pharmaceutical ingredient (API). Additionally, existing spaceflight drug stability studies were reviewed to identify research gaps to be addressed prior to exploration missions. Data were extracted from the six spaceflight studies to quantify API loss for 36 drug products with long-duration exposure to spaceflight. Medications stored for up to 2.4 years in low Earth orbit (LEO) exhibit a small increase in the rate of API loss with a corresponding increase in risk of product failure. Overall, the potency for all spaceflight-exposed medications remains within 10% of terrestrial lot-matched control with a ~1.5 increase in degradation rate. All existing studies of spaceflight drug stability have focused primarily on repackaged solid oral medications, which is important because non-protective repackaging is a well-established factor contributing to loss of drug potency. The factor most detrimental to drug stability appears to be nonprotective drug repackaging, based on premature failure of drug products in the terrestrial control group. The result of this study supports a critical need to evaluate the effects of current repackaging processes on drug shelf life, and to develop and validate suitable protective repackaging strategies that help assure the stability of medications throughout the full duration of exploration space missions.

Identification of Staphylococcus aureus Penicillin Binding Protein 4 (PBP4) Inhibitors

Methicillin-resistant Staphylococcus aureus (MRSA) is a global healthcare concern. Such resistance has historically been attributed to the acquisition of mecA (or mecC), which encodes an alternative penicillin binding protein, PBP2a, with low β-lactam affinity. However, recent studies have indicated that penicillin binding protein 4 (PBP4) is also a critical determinant of S. aureus methicillin resistance, particularly among community-acquired MRSA strains. Thus, PBP4 has been considered an intriguing therapeutic target as corresponding inhibitors may restore MRSA β-lactam susceptibility. In addition to its role in antibiotic resistance, PBP4 has also recently been shown to be required for S. aureus cortical bone osteocyte lacuno-canalicular network (OLCN) invasion and colonization, providing the organism with a niche for re-occurring bone infection. From these perspectives, the development of PBP4 inhibitors may have tremendous impact as agents that both reverse methicillin resistance and inhibit the organism’s ability to cause chronic osteomyelitis. Accordingly, using a whole-cell high-throughput screen of a 30,000-member small molecule chemical library and secondary assays we identified putative S. aureus PBP4 inhibitors. Quantitative reverse transcriptase mediated PCR and PBP4 binding assays revealed that hits could be further distinguished as compounds that reduce PBP4 expression versus compounds that are likely to affect the protein’s function. We also showed that 6.25 µM (2.5 µg/mL) of the lead candidate, 9314848, reverses the organism’s PBP4-dependent MRSA phenotype and inhibits its ability to traverse Microfluidic-Silicon Membrane-Canalicular Arrays (µSiM-CA) that model the OLCN orifice. Collectively, these molecules may represent promising potential as PBP4-inhibitors that can be further developed as adjuvants for the treatment of MRSA infections and/or osteomyelitis prophylactics.

Noncanonical Role of Telomerase in Regulation of Microvascular Redox Environment With Implications for Coronary Artery Disease

Telomerase reverse transcriptase (TERT) (catalytic subunit of telomerase) is linked to the development of coronary artery disease (CAD); however, whether the role of nuclear vs. mitchondrial actions of TERT is involved is not determined. Dominant-negative TERT splice variants contribute to decreased mitochondrial integrity and promote elevated reactive oxygen species production. We hypothesize that a decrease in mitochondrial TERT would increase _mtDNA damage, promoting a pro-oxidative redox environment. The goal of this study is to define whether mitochondrial TERT is sufficient to maintain nitric oxide as the underlying mechanism of flow-mediated dilation by preserving _mtDNA integrity.Immunoblots and quantitative polymerase chain reaction were used to show elevated levels of splice variants α- and β-deletion TERT tissue from subjects with and without CAD. Genetic, pharmacological, and molecular tools were used to manipulate TERT localization. Isolated vessel preparations and fluorescence-based quantification of _mtH₂O₂ and NO showed that reduction of TERT in the nucleus increased flow induced NO and decreased _mtH₂O₂ levels, while prevention of mitochondrial import of TERT augmented pathological effects. Further elevated _mtDNA damage was observed in tissue from subjects with CAD and initiation of _mtDNA repair mechanisms was sufficient to restore NO-mediated dilation in vessels from patients with CAD. The work presented is the first evidence that catalytically active mitochondrial TERT, independent of its nuclear functions, plays a critical physiological role in preserving NO-mediated vasodilation and the balance of mitochondrial to nuclear TERT is fundamentally altered in states of human disease that are driven by increased expression of dominant negative splice variants.

The influence of anastomotic techniques on postoperative anastomotic complications: Results of the Oesophago-Gastric Anastomosis Audit

BACKGROUND

The optimal anastomotic techniques in esophagectomy to minimize rates of anastomotic leakage and conduit necrosis are not known. The aim of this study was to assess whether the anastomotic technique was associated with anastomotic failure after esophagectomy in the international Oesophago-Gastric Anastomosis Audit cohort.

METHODS

This prospective observational multicenter cohort study included patients undergoing esophagectomy for esophageal cancer over 9 months during 2018. The primary exposure was the anastomotic technique, classified as handsewn, linear stapled, or circular stapled. The primary outcome was anastomotic failure, namely a composite of anastomotic leakage and conduit necrosis, as defined by the Esophageal Complications Consensus Group. Multivariable logistic regression modeling was used to identify the association between anastomotic techniques and anastomotic failure, after adjustment for confounders.

RESULTS

Of the 2238 esophagectomies, the anastomosis was handsewn in 27.1%, linear stapled in 21.0%, and circular stapled in 51.9%. Anastomotic techniques differed significantly by the anastomosis sites (P < .001), with the majority of neck anastomoses being handsewn (69.9%), whereas most chest anastomoses were stapled (66.3% circular stapled and 19.3% linear stapled). Rates of anastomotic failure differed significantly among the anastomotic techniques (P < .001), from 19.3% in handsewn anastomoses, to 14.0% in linear stapled anastomoses, and 12.1% in circular stapled anastomoses. This effect remained significant after adjustment for confounding factors on multivariable analysis, with an odds ratio of 0.63 (95% CI, 0.46-0.86; P = .004) for circular stapled versus handsewn anastomosis. However, subgroup analysis by anastomosis site suggested that this effect was predominantly present in neck anastomoses, with anastomotic failure rates of 23.2% versus 14.6% versus 5.9% for handsewn versus linear stapled anastomoses versus circular stapled neck anastomoses, compared with 13.7% versus 13.8% versus 12.2% for chest anastomoses.

CONCLUSIONS

Handsewn anastomoses appear to be independently associated with higher rates of anastomotic failure compared with stapled anastomoses. However, this effect seems to be largely confined to neck anastomoses, with minimal differences between techniques observed for chest anastomoses. Further research into standardization of anastomotic approach and techniques may further improve outcomes.

658 The Use of AlliumTM Stents in the Management of Ureteric Strictures

Aim

Stents are widely used in the management of ureteric strictures but require changes every 6–12 months and stent related symptoms are commonly reported. AlliumTM ureteric stents are large calibre, metallic stents that aim to reduce the incidence of stent-related complications, with an indwelling time up to three years. These were introduced within our local hospital trust for patients requiring frequent stent changes and this study aims to review the early use of AlliumTM stents and associated complications.

Method

An electronic database of patients was searched for records including the words “Allium stent” between 01/01/17–01/01/21. The resulting patient electronic records were then interrogated to extract data.

Results

13 patients were included in data analysis. Mean age was 62.7 years and male:female ratio was 6:7. 5 underwent antegrade insertion and 8 retrograde. 3 were inserted under local anaesthetic and 10 under general. Median follow-up time was 459 days.

No cases of renal deterioration were noted, and no patients sought medical attention with pain or irritative symptoms. The majority remained in situ, however one patient reported spontaneous passage of the stent; and one patient later required a nephrectomy, necessitating stent removal. Three patients developed post-operative urinary tract infections (two requiring hospital admission); two patients required further intervention for urolithiasis causing stent blockage; and two patients died from other disease processes prior to analysis.

Conclusions

There are clear advantages in reducing repeated admission and anaesthesia for patients. Initial results demonstrate good patency and tolerability of AlliumTM stents though further investigation is required to analyse the long-term benefits.

Leveraging metabolic modeling to identify functional metabolic alterations associated with COVID-19 disease severity

OBJECTIVE

Since the COVID-19 pandemic began in early 2020, SARS-CoV2 has claimed more than six million lives world-wide, with over 510 million cases to date. To reduce healthcare burden, we must investigate how to prevent non-acute disease from progressing to severe infection requiring hospitalization.

METHODS

To achieve this goal, we investigated metabolic signatures of both non-acute (out-patient) and severe (requiring hospitalization) COVID-19 samples by profiling the associated plasma metabolomes of 84 COVID-19 positive University of Virginia hospital patients. We utilized supervised and unsupervised machine learning and metabolic modeling approaches to identify key metabolic drivers that are predictive of COVID-19 disease severity. Using metabolic pathway enrichment analysis, we explored potential metabolic mechanisms that link these markers to disease progression.

RESULTS

Enriched metabolites associated with tryptophan in non-acute COVID-19 samples suggest mitigated innate immune system inflammatory response and immunopathology related lung damage prevention. Increased prevalence of histidine- and ketone-related metabolism in severe COVID-19 samples offers potential mechanistic insight to musculoskeletal degeneration-induced muscular weakness and host metabolism that has been hijacked by SARS-CoV2 infection to increase viral replication and invasion.

CONCLUSIONS

Our findings highlight the metabolic transition from an innate immune response coupled with inflammatory pathway inhibition in non-acute infection to rampant inflammation and associated metabolic systemic dysfunction in severe COVID-19.

Simulated Leaching of Foliar Applied Copper Bactericides on the Soil Microbiome Utilizing Various Beta Diversity Resemblance Measurements

Copper bactericides are routinely used to control Xanthomonas perforans (XP), causal agent of bacterial spot of tomato. Given the widespread tolerance to copper in XP strains in FL, USA, nanotechnology-based elemental composites have gained interest for their potential applications in agriculture in part due to their enhanced antimicrobial properties and toxicity to copper-tolerant strains. However, little is known about the potential impact of conventional copper bactericides as well as nano-based elemental composites on soil microbial communities, as determined by high-throughput sequencing of the 16S rDNA. We compared the effects of 2 and 200 μg/mL of core-shell (CS), a metallic copper composite, and a conventional copper bactericide + mancozeb (Cu+Man) on the soil microbiome. These treatments were compared to three controls, the microbial profile of the soil prior to application of copper products, a water application, and spiking the soil with a soilborne phytobacterium, Ralstonia solanacearum (RS). The RS treatment was included to determine if downstream analysis could detect the artificial inoculation. Utilizing multiple β diversity measurements, each emphasizing various tenets of ecology, provided a greater perspective of the effects the treatments had on the microbiome. Analysis of HTS data revealed that the two treatments containing field applied rates of metallic copper, CS 200 and Cu+Man, had the largest impact on the soil microbiome at seven-days posttreatment compared to water. However, we simulated field applied rates of CS 200 entering the soil by treating soil with CS 2 and determined this concentration had a negligible effect on the soil microbiome. IMPORTANCE Nanotechnology-based elemental composites have gained popularity for their potential applications in plant disease management due to their enhanced antimicrobial properties. However, little is known about their potential impact on the environment. Foliar applications of nano metallic composites upon leaching into the soil have the potential to impact soil microbial populations that in turn influence soil health. Utilizing multiple β diversity measurements, high-throughput sequencing analysis revealed that field applied rates of metallic copper (200 μg/mL) from an advanced copper composite (core-shell [CS]) and a conventional copper bactericide in combination with mancozeb had the largest impact on the soil microbiome compared to water and nontreated control. To simulate leaching from the leaf surface, a lower concentration (2 μg/mL) of CS was also applied to the soil and had a negligible effect on the soil microbiome. Thus, field applied rates of CS may have a minimal effect on soil microbial communities.

Relevance of necroptosis in the hearts subjected to acute versus chronic ischemia/reperfusion injury

Funding Acknowledgements

Type of funding sources: Public Institution(s). Main funding source(s): Slovak Research and Development Agency

Medical Research Council Grant

Necroptosis, a necrosis-like programmed cell death modality dependent on the activity of receptor-interacting protein kinase 3 (RIP3) and mixed lineage domain kinase domain-like pseudokinase (MLKL), plays a prominent role in mediating myocardial ischemia/reperfusion injury. However, the extent to which necroptosis contributes to such damage under short and long reperfusion has not been evaluated in detail. In Wistar rat hearts, subjected to global 30-min ischemia followed by an acute 10-min reperfusion period, with compromised cardiac function, no changes in the protein expression of the main necroptotic markers (pThr231/Ser232-RIP3, MLKL) were found. Likewise, the non-canonical pathways of necroptosis involving Ca2+/calmodulin dependent protein kinase II–mitochondrial permeability transition pore (CaMKII–mPTP) or phosphoglycerate mutase 5–dynamin-related protein 1 (PGAM5–Drp1) axes were unlikely affected by such short reperfusion. In contrast, hearts subjected to global 30-min ischemia followed by a prolonged 40-min reperfusion period exhibited worsened hemodynamic parameters what was accompanied by the increased levels of RIP3, pSer229-RIP3 and MLKL. Moreover, this reperfusion period induced MLKL translocation to the plasma membrane, indicating necroptosis execution with resultant very likely cell disruption. Similarly, activated necroptosis, evidenced by the higher levels of proteins of the canonical pathway, has been suggested to contribute to the pathogenesis of post-infarction heart failure (30-min ischemia, 42-day reperfusion). Collectively, these findings suggest that short reperfusion seems to be insufficient to induce necroptosis in the heart and the molecular mechanisms being activated during the longer reperfusion phase are needed to promote necroptotic cell dying. Therefore, inhibition of necroptosis might represent a cardioprotective strategy in the settings of chronic, but not acute myocardial ischemia/reperfusion injury.

Postoperative outcomes in oesophagectomy with trainee involvement

BACKGROUND

The complexity of oesophageal surgery and the significant risk of morbidity necessitates that oesophagectomy is predominantly performed by a consultant surgeon, or a senior trainee under their supervision. The aim of this study was to determine the impact of trainee involvement in oesophagectomy on postoperative outcomes in an international multicentre setting.

METHODS

Data from the multicentre Oesophago-Gastric Anastomosis Study Group (OGAA) cohort study were analysed, which comprised prospectively collected data from patients undergoing oesophagectomy for oesophageal cancer between April 2018 and December 2018. Procedures were grouped by the level of trainee involvement, and univariable and multivariable analyses were performed to compare patient outcomes across groups.

RESULTS

Of 2232 oesophagectomies from 137 centres in 41 countries, trainees were involved in 29.1 per cent of them (n = 650), performing only the abdominal phase in 230, only the chest and/or neck phases in 130, and all phases in 315 procedures. For procedures with a chest anastomosis, those with trainee involvement had similar 90-day mortality, complication and reoperation rates to consultant-performed oesophagectomies (P = 0.451, P = 0.318, and P = 0.382, respectively), while anastomotic leak rates were significantly lower in the trainee groups (P = 0.030). Procedures with a neck anastomosis had equivalent complication, anastomotic leak, and reoperation rates (P = 0.150, P = 0.430, and P = 0.632, respectively) in trainee-involved versus consultant-performed oesophagectomies, with significantly lower 90-day mortality in the trainee groups (P = 0.005).

CONCLUSION

Trainee involvement was not found to be associated with significantly inferior postoperative outcomes for selected patients undergoing oesophagectomy. The results support continued supervised trainee involvement in oesophageal cancer surgery.

Multifunctional Surface, Subsurface, and Systemic Therapeutic (MS3T) Formulation for the Control of Citrus Canker

A multifunctional surface, subsurface and systemic therapeutic (MS3T) formulation comprised of two bactericides, both didecyldimethylammonium chloride (DDAC) and a zinc (Zn)-chelate, was developed as an alternative to copper pesticides for crop protection. Agricultural grade chemicals were used to prepare MS3T formulations. Minimal inhibitory concentration (MIC) was determined to be tested in vitro against Xanthomonas alfalfae subsp. citrumelonis (herein called Xa), Escherichia coli (E. coli), and Pseudomonas syringae (Ps). Assessment of the phytotoxic potential was carried out on tomato under greenhouse conditions. Moreover, field trials were conducted during three consecutive years on grapefruit (Chrysopelea paradise) groves to evaluate efficacy against citrus canker (Xanthomonas citri subsp. citri), scab (Elsinoe fawcetti), and melanose (Diaporthe citri). In addition to disease control, improvements to both fruit yield and quality were observed likely due to the nutritional activity of MS3T via the sustained release of plant nutrients (Zn and nitrogen). Zn residues of leaf tissues were analyzed via atomic absorption spectroscopy (AAS) at various time points before and after MS3T foliar applications throughout the duration of the 2018 field trial. Field trial results demonstrated MS3T to be an effective alternative to copper (Cu)-based formulations for the control of citrus canker.

Predictors of death and new disability after critical illness: a multicentre prospective cohort study

PURPOSE

This study aimed to determine the prevalence and predictors of death or new disability following critical illness.

METHODS

Prospective, multicentre cohort study conducted in six metropolitan intensive care units (ICU). Participants were adults admitted to the ICU who received more than 24 h of mechanical ventilation. The primary outcome was death or new disability at 6 months, with new disability defined by a 10% increase in the WHODAS 2.0.

RESULTS

Of 628 patients with the primary outcome available (median age of 62 [49-71] years, 379 [61.0%] had a medical admission and 370 (58.9%) died or developed new disability by 6 months. Independent predictors of death or new disability included age [OR 1.02 (1.01-1.03), P = 0.001], higher severity of illness (APACHE III) [OR 1.02 (1.01-1.03), P < 0.001] and admission diagnosis. Compared to patients with a surgical admission diagnosis, patients with a cardiac arrest [OR (95% CI) 4.06 (1.89-8.68), P < 0.001], sepsis [OR (95% CI) 2.43 (1.32-4.47), P = 0.004], or trauma [OR (95% CI) 6.24 (3.07-12.71), P < 0.001] diagnosis had higher odds of death or new disability, while patients with a lung transplant [OR (95% CI) 0.21 (0.07-0.58), P = 0.003] diagnosis had lower odds. A model including these three variables had good calibration (Brier score 0.20) and acceptable discriminative power with an area under the receiver operating characteristic curve of 0.76 (95% CI 0.72-0.80).

CONCLUSION

Less than half of all patients mechanically ventilated for more than 24 h were alive and free of new disability at 6 months after admission to ICU. A model including age, illness severity and admission diagnosis has acceptable discriminative ability to predict death or new disability at 6 months.

Mortality from esophagectomy for esophageal cancer across low, middle, and high-income countries: An international cohort study

BACKGROUND

No evidence currently exists characterising global outcomes following major cancer surgery, including esophageal cancer. Therefore, this study aimed to characterise impact of high income countries (HIC) versus low and middle income countries (LMIC) on the outcomes following esophagectomy for esophageal cancer.

METHOD

This international multi-center prospective study across 137 hospitals in 41 countries included patients who underwent an esophagectomy for esophageal cancer, with 90-day follow-up. The main explanatory variable was country income, defined according to the World Bank Data classification. The primary outcome was 90-day postoperative mortality, and secondary outcomes were composite leaks (anastomotic leak or conduit necrosis) and major complications (Clavien-Dindo Grade III - V). Multivariable generalized estimating equation models were used to produce adjusted odds ratios (ORs) and 95% confidence intervals (CI95%).

RESULTS

Between April 2018 to December 2018, 2247 patients were included. Patients from HIC were more significantly older, with higher ASA grade, and more advanced tumors. Patients from LMIC had almost three-fold increase in 90-day mortality, compared to HIC (9.4% vs 3.7%, p < 0.001). On adjusted analysis, LMIC were independently associated with higher 90-day mortality (OR: 2.31, CI95%: 1.17-4.55, p = 0.015). However, LMIC were not independently associated with higher rates of anastomotic leaks (OR: 1.06, CI95%: 0.57-1.99, p = 0.9) or major complications (OR: 0.85, CI95%: 0.54-1.32, p = 0.5), compared to HIC.

CONCLUSION

Resections in LMIC were independently associated with higher 90-day postoperative mortality, likely reflecting a failure to rescue of these patients following esophagectomy, despite similar composite anastomotic leaks and major complication rates to HIC. These findings warrant further research, to identify potential issues and solutions to improve global outcomes following esophagectomy for cancer.

Comparison of short-term outcomes from the International Oesophago-Gastric Anastomosis Audit (OGAA), the Esophagectomy Complications Consensus Group (ECCG), and the Dutch Upper Gastrointestinal Cancer Audit (DUCA)

BACKGROUND

The Esophagectomy Complications Consensus Group (ECCG) and the Dutch Upper Gastrointestinal Cancer Audit (DUCA) have set standards in reporting outcomes after oesophagectomy. Reporting outcomes from selected high-volume centres or centralized national cancer programmes may not, however, be reflective of the true global prevalence of complications. This study aimed to compare complication rates after oesophagectomy from these existing sources with those of an unselected international cohort from the Oesophago-Gastric Anastomosis Audit (OGAA).

METHODS

The OGAA was a prospective multicentre cohort study coordinated by the West Midlands Research Collaborative, and included patients undergoing oesophagectomy for oesophageal cancer between April and December 2018, with 90 days of follow-up.

RESULTS

The OGAA study included 2247 oesophagectomies across 137 hospitals in 41 countries. Comparisons with the ECCG and DUCA found differences in baseline demographics between the three cohorts, including age, ASA grade, and rates of chronic pulmonary disease. The OGAA had the lowest rates of neoadjuvant treatment (OGAA 75.1 per cent, ECCG 78.9 per cent, DUCA 93.5 per cent; P < 0.001). DUCA exhibited the highest rates of minimally invasive surgery (OGAA 57.2 per cent, ECCG 47.9 per cent, DUCA 85.8 per cent; P < 0.001). Overall complication rates were similar in the three cohorts (OGAA 63.6 per cent, ECCG 59.0 per cent, DUCA 62.2 per cent), with no statistically significant difference in Clavien-Dindo grades (P = 0.752). However, a significant difference in 30-day mortality was observed, with DUCA reporting the lowest rate (OGAA 3.2 per cent, ECCG 2.4 per cent, DUCA 1.7 per cent; P = 0.013).

CONCLUSION

Despite differences in rates of co-morbidities, oncological treatment strategies, and access to minimal-access surgery, overall complication rates were similar in the three cohorts.

Five-year efficacy and safety of tildrakizumab in patients with moderate-to-severe psoriasis who respond at week 28: pooled analyses of two randomized phase III clinical trials (reSURFACE 1 and reSURFACE 2)

BACKGROUND

The phase III reSURFACE 1 and reSURFACE 2 (NCT01722331/NCT01729754) trials of the anti-interleukin-23p19 monoclonal antibody tildrakizumab (TIL) for psoriasis treatment are complete.

OBJECTIVES

We present 5-year pooled data from reSURFACE 1 and reSURFACE 2.

METHODS

reSURFACE 1 and reSURFACE 2 were double-blind, randomized, controlled studies with optional long-term extensions. Adults with moderate-to-severe chronic plaque psoriasis were randomized 2 : 2 : 1 to TIL 100 mg (TIL 100) or 200 mg (TIL 200) or placebo at weeks 0 and 4, and every 12 weeks thereafter [reSURFACE 2 included an etanercept (ETN) arm]. Efficacy outcomes included proportions of patients achieving absolute and relative improvement from baseline Psoriasis Area and Severity Index (PASI) score through week 244 in TIL responders (≥ 75% improvement from baseline PASI; PASI 75 response) continuously receiving the same dose and ETN partial responders and nonresponders (PASI < 75 response) switched to TIL 200 at week 28. Safety was assessed from adverse events (AEs) in all patients as treated.

RESULTS

Efficacy analyses included 329 and 227 week 28 responders to TIL 100 and TIL 200, respectively, and 121 ETN partial responders/nonresponders switched to TIL 200 at week 28. Of TIL 100 or TIL 200 responders and ETN partial responders/nonresponders entering the extensions, 235/302, 176/213 and 85/107, respectively, were evaluated at week 244, and 88·7%, 92·5% and 81·3%, respectively, achieved PASI 75 response. Exposure-adjusted rates of serious AEs were 6·3 and 6·0 patients with events per 100 patient-years of TIL 100 and TIL 200, respectively.

CONCLUSIONS

TIL treatment provided sustained disease control over 5 years in week 28 TIL responders and ETN partial responders/nonresponders, with a reassuring safety profile.

Copper-fixed quat: a hybrid nanoparticle for application as a locally systemic pesticide (LSP) to manage bacterial spot disease of tomato

The development of bacterial tolerance against pesticides poses a serious threat to the sustainability of food production. Widespread use of copper (Cu)-based products for plant disease management has led to the emergence of copper-tolerant pathogens such as Xanthomonas perforans (X. perforans) strains in Florida, which is very destructive to the tomato (Solanum lycopersicum) industry. In this study, we report a hybrid nanoparticle (NP)-based system, coined Locally Systemic Pesticide (LSP), which has been designed for improved efficacy compared to conventional Cu-based bactericides against Cu-tolerant X. perforans. The silica core-shell structure of LSP particles makes it possible to host ultra-small Cu NPs (<10 nm) and quaternary ammonium (Quat) molecules on the shell. The morphology, release of Cu and Quat, and subsequent in vitro antimicrobial properties were characterized for LSP NPs with core diameters from 50 to 600 nm. A concentration of 4 μg mL^-1 (Cu): 1 μg mL^-1 (Quat) was found to be sufficient to inhibit the growth of Cu-tolerant X. perforans compared to 100 μg mL^-1 (metallic Cu) required with standard Kocide 3000. Wetting properties of LSP exhibited contact angles below 60°, which constitutes a significant improvement from the 90° and 85° observed with water and Kocide 3000, respectively. The design was also found to provide slow Cu release to the leaves upon water washes, and to mitigate the phytotoxicity of water-soluble Cu and Quat agents. With Cu and Quat bound to the LSP silica core-shell structure, no sign of phytotoxicity was observed even at 1000 μg mL^-1 (Cu). In greenhouse and field experiments, LSP formulations significantly reduced the severity of bacterial spot disease compared to the water control. Overall, the study highlights the potential of using LSP particles as a candidate for managing tomato bacterial spot disease and beyond.

A simple novel training model for teaching suprapubic catheter (SPC) exchange

OBJECTIVES

To develop a suprapubic catheter (SPC) training model as no specific realistic training model exists to replicate SPC exchange where a catheter tract is present.

MATERIALS AND METHODS

We describe a novel, anatomically realistic, animal simulator model for use in SPC training, which was trialed at a national urology simulation boot camp by new urology trainees and validated by expert urologists. A scale reproduction of an abdominal wall was created using a porcine abdominal wall. A segment of small bowel was stitched around a size 16F Foley catheter to form a tract. Abdominal wall tissue was excised cylindrically to create an opening, and the small bowel tract was passed through the abdominal wall and sutured anteriorly, producing a realistic SPC tract: inferiorly, the tract was anastomosed to a porcine urinary bladder. This model was evaluated by 10 expert urologists for content validity with an 8-item 5-point rating scale used to evaluate domains relevant to the simulator.

RESULTS

The domains were scored between 1 and 5 by 10 expert urologists, 1 being «strongly disagree» and 5 being «strongly agree». The average expert ratings of the domains were then calculated and tabulated following the training course. There was an average global rating of 4.2/5 for the model, with an average usefulness for training score of 4.6/5.

CONCLUSION

The feedback from experts and trainees (informal) was overwhelmingly positive. On average, our experts reported high satisfaction with their experience using this simulator as a training tool.

Optimization of 4-Substituted Benzenesulfonamide Scaffold To Reverse Acinetobacter baumannii Serum-Adaptive Efflux Associated Antibiotic Tolerance

Acinetobacter baumannii is a nosocomial pathogen of urgent concern for public health due to rising rates of multidrug and pandrug resistance. In the context of environmental cues such as growth in human serum, A. baumannii is known to display adaptive efflux, in which a multitude of efflux-associated genes are upregulated, resulting in efflux-mediated drug tolerance in strains that are otherwise susceptible to antibiotic therapy. Previously, we identified a sulfonamide-containing scaffold molecule (ABEPI1) that reversed serum-associated antibiotic tolerance in A. baumannii. Herein, we present structure-activity relationship studies on 29 newly synthesized analogues. These molecules were characterized for their ability to potentiate multiple antibiotics in serum, reduce serum-associated ethidium bromide efflux and depolarize bacterial cell membranes. In addition, they were assessed for toxicity to mammalian cells. Collectively, these molecules may represent promising potential adjuvants for use in combination with new and existing antibiotics to treat A. baumannii bacterial infections.

Surprise Diagnosis of COVID-19 following Neuroimaging Evaluation for Unrelated Reasons during the Pandemic in Hot Spots

During the height of the recent outbreak of coronavirus 19 (COVID-19) in New York City, almost all the hospital emergency departments were inundated with patients with COVID-19, who presented with typical fever, cough, and dyspnea. A small number of patients also presented with either unrelated conditions (such as trauma) or other emergencies, and some of which are now known to be associated with COVID-19 (such as stroke). We report such a scenario in 17 patients who were admitted and investigated with CT spine imaging and CT angiography for nonpulmonary reasons (trauma = 13, stroke = 4). Their initial work-up did not suggest COVID-19 as a diagnosis but showed unsuspected/incidental lung findings, which led to further investigations and a diagnosis of COVID-19.

FRI0309 DAILY SELF-REPORTED FLARE PROFILES IN AXIAL SPONDYLOARTHRITIS: ASSOCIATIONS BETWEEN FLARE, SYMPTOMS AND BEHAVIOUR

Background:

Axial spondyloarthritis (axSpA) is a chronic inflammatory disease, characterised by fluctuating periods of flare and remission. Flare is a multidimensional change of disease state; whereby flare definitions have previously been formulated using validated composite indices, or through qualitative retrospective investigation of flare states. Smartphone technologies for tracking disease symptoms provide unique, daily insights into self-reported individual flare experience, and may present an opportunity to gain a more complete understanding of flare burden and symptom patterns.

Objectives:

To assess frequency and characteristics of axSpA flares, utilising data collected in the uMotif symptom tracking app.

Methods:

Patients with axSpA attending the Royal National Hospital for Rheumatic Diseases in Bath were invited to participate. Through the uMotif app, patients were sent daily reminders to log flare, pain, fatigue, sleep, recommended exercise, mood and stress using 5-point Likert scales, in addition to optional variables such as smoking and menstrual cycle. Self-reported periods of flare were identified. For each patient reporting flare within the study period, a mean ‘flare’ and ‘non-flare’ score was calculated for each variable. Paired t-tests were conducted for each variable, to investigate which variables correlate with flare status.

Results:

Between 5th April 2018 and 8th March 2019, 174 patients consented for research and logged a mean of 99.73 (SD 99.97, range 1 - 323 days) days of data. 136/174 (78%) patients recorded at least 1 flare, with 1330 flares recorded in total. For patients reporting at least 1 flare, each flare lasted a mean of 2.20 days (SD 2.53 days, range 1 – 33 days), with a mean frequency of once every 45.19 days (SD 53.06, range 3.2 -314 days). Significant relationships were identified between flare status and uMotif scores (Table 1).

Table 1.

Paired t-tests: flare vs. non-flare scores for each variable

Estimated difference^p-valueN95% CI (lower limit)95% CI (upper limit)Variable-0.870.266-2.630.88Red Painful Eyes-0.670.000*130-0.78-0.56Pain-0.570.004*25-0.94-0.20Chest Pain-0.510.005*15-0.83-0.18Hot Flushes-0.500.000*129-0.61-0.40Fatigue-0.440.1962-2.231.35Blood in Stool-0.380.000*128-0.47-0.29Mood-0.360.000*127-0.52-0.20Anti-Inflammatory Use-0.360.000*128-0.48-0.23Recommended Exercise-0.340.000*33-0.51-0.17Confidence in Self-Management-0.260.000*128-0.37-0.15Stress-0.250.17015-0.620.12Screen Time-0.190.000*130-0.26-0.12Sleep Quality-0.150.45812-0.590.28Menstrual Cycle-0.110.10322-0.250.02Eyesight0.090.1953-0.120.30Flare of Psoriasis0.050.65626-0.170.26Medication Adherence0.040.7973-0.530.61Smoking Today-0.030.48450-0.110.05Caffeine Intake

N= number of patients with both a flare and non-flare entry for each variable; CI=confidence interval

Higher variable scores indicate more positive outcomes (e.g. a higher pain score indicates less pain)

^Estimated difference between flare and non-flare entries (e.g. on average, the mean pain score of a flare entry is 0.67 [0.56– 0.78 CI] less than a non-flare entry)

*p<0.01

Conclusion:

These findings demonstrate significant relationships between a variety of patient-reported symptoms and flare, including variables that to our knowledge, have not yet been explored in axSpA. Small estimated differences were found between scores for ‘flare’ versus ‘no-flare’. Further work is needed to characterise fluctuating flare/no-flare patterns of individuals tracking daily symptoms in the uMotif app. In future research, it will be important to determine whether there is a chronological pattern of variables during the pre-flare period that can predict a flare. Greater understanding of such patterns may allow identification of the optimal timing of intervention to prevent a period of flare and improve quality of life for patients with axSpA.

Acknowledgments:

We thank UCB for funding use of the uMotif application.

Disclosure of Interests:

Rosie Barnett: None declared, Stanley Ng: None declared, Simon Jones: None declared, Matthew Young: None declared, Raj Sengupta Grant/research support from: Research grants from UCB, Pfizer, Abbvie and Novartis, Speakers bureau: Received honoraria for giving talks from Abbvie, Biogen, UCB, Novartis, Pfizer

Teachers' mindsets in medical education: A pilot survey of clinical supervisors

Purpose: Current medical education models maintain that competencies such as professionalism and communication can be taught; however, some argue that certain attributes that make up these competencies, such as empathy, are fixed. Teachers' implicit theories, or mindsets (beliefs about the fixed versus learnable nature of human attributes) have been shown to impact their teaching and assessment practices; but little work has explored mindsets in medical education. We examined clinical supervisors' mindsets of two cognitive attributes (intelligence and clinical reasoning) and two affective attributes (moral character and empathy).Methods: Clinical supervisors (n = 40) from three specialities completed a survey designed to measure mindsets using two existing instruments for intelligence and moral character and 18 new items for clinical reasoning and empathy. Participants completed the survey twice for test-retest reliability (n = 25).Results: New items had satisfactory psychometric properties. Clinical supervisors' mindsets were mixed. Only 8% of participants saw clinical reasoning as fixed while more saw empathy (45%), intelligence (53%), and moral character (53%) as fixed - running counter to current educational models that characterize these attributes as learnable.Conclusion: This study provides evidence supporting the use of these new tools to measure mindsets that may help to better understand the impact of mindsets on medical education.

Ultrasonic drilling for the characterisation of building stones and salt induced decay

Historic stone buildings can experience severe decay through salt induced weathering. Decay can be easily seen with the eye but can also occur below the surface. Characterising the changes in the material's structural properties induced by weathering is essential for the evaluation of durability of the stone and for the decision on the best conservation strategy to maintain built heritage. Minimally invasive, in situ tools are needed to establish the location and state of decay at the site. Here an ultrasonic drilling tool is introduced with a specially manufactured tip to monitor subsurface properties of sandstones. Different types of sandstones with varying compressive strength are tested and an artificially weathered sample is investigated. The tool tip wear and exerted force on the drilled samples are evaluated and compared to conventional drilling. Ultrasonic drilling shows promising results for the use in conservation science to assess stone properties and decay.

Minimal Compared With Standard Monitoring During Sofosbuvir-Based Hepatitis C Treatment: A Randomized Controlled Trial

Background

Oral direct-acting antiviral agents (DAAs) for hepatitis C virus (HCV) became government subsidized in Australia in March 2016, bringing the interferon era to a close. The ideal monitoring schedule for patients receiving DAAs is unclear.

Methods

This study is a randomized controlled trial comparing standard with minimal monitoring in adults receiving sofosbuvir-based therapy for HCV genotypes 1 or 3. Exclusion criteria were cirrhosis or predicted poor adherence. Standard monitoring included blood tests and face-to-face clinic visits at treatment weeks 4 and 12 and 12 weeks after treatment completion. Minimal monitoring included a phone call at weeks 4 and 12 and one set of blood tests plus a clinic visit 12 weeks after treatment completion. The coprimary outcomes were as follows: (1) proportion of participants with sustained virological response; (2) staff time spent on patient support; and (3) patient satisfaction on a 10-point Likert scale.

Results

Thirty-six patients were randomized to standard monitoring and 38 to minimal monitoring. Sustained virological response at 12 weeks after the end of treatment was documented in 32 of 36 (89%) in the standard versus 37 of 38 (97%) in the minimal monitoring group. Staff time was nonsignificantly longer in the standard group (median 69 [interquartile range {IQR}, 54–80] versus 52 [IQR, 40–75] minutes). Patient satisfaction scores were not different (mean 9.8 of 10 standard versus 9.6 of 10 minimal group). There was no difference in adverse events or unplanned hospital visits; mean per-patient blood test costs were higher in the standard monitoring group ($432 versus $123, P < .001).

Conclusions

On-treatment monitoring with blood tests and clinic visits may not be necessary during sofosbuvir-based HCV treatment in selected patients.

Control of Citrus Canker in Greenhouse and Field with a Zinc, Urea, and Peroxide Ternary Solution

Accumulation of toxic copper in soil and development of copper-resistant pests are emerging challenges currently faced by the agricultural community worldwide. As an alternative, we have developed a ternary zinc chelate solution (TSOL) pesticide where zinc ions are the primary active ingredient. The material is composed of zinc, urea, and hydrogen peroxide. Urea was chosen as it is widely used as a plant fertilizer and can also bind to both zinc and hydrogen peroxide. No phytotoxicity was observed with TSOL on Meyer lemon (Citrus × meyeri) seedlings at a field spray rate of 800 μg/mL Zn metal concentration. Antimicrobial studies showed that TSOL exhibited improved killing efficacy against Escherichia coli and Xanthomonas alfalfae compared to Zn ions alone. Citrus canker field trials in a grapefruit (Chrysopelea paradisi) grove over three years showed that TSOL provided comparable disease protection to copper products at an equivalent or lower metal content.

Assessment of the current D-dimer cutoff point in pulmonary embolism workup at a single institution: Retrospective study

Background:

The currently used D-dimer (DD) cutoff point is associated with a large number of negative CT-pulmonary angiographies (CTPA). We hypothesized presence of deficiency in the current cutoff and a need to look for a better DD threshold.

Materials and Methods:

We conducted a retrospective medical records analysis of all patients who had a CTPA as part of pulmonary embolism (PE) workup over a 1-year period. All emergency room (ER) patients who had DD assay checked prior to CTPA were included in the analysis. We assessed our institutional cutoff point and tried to test other presumptive DD thresholds retrospectively.

Results:

At our institution 1591 CTPA were performed in 2014, with 1220 scans (77%) performed in the ER. DD test was ordered prior to CTPA imaging in 238 ER patients (19.5%) as part of the PE workup. PE was diagnosed in 14 cases (6%). The sensitivity and specificity of the currently used DD cutoff (0.5 mcg/mL) were found to be 100% and 13%, respectively. Shifting the cutoff value from 0.5 to 0.85 mcg/mL would result in a significant increase in the specificity from 13% to 51% while maintaining the same sensitivity of 100%. This would make theoretically 84 CTPA scans, corresponding to 35% of CTPA imaging, unnecessary because DD would be considered negative based on this presumptive threshold.

Conclusions:

Our results suggest a significant deficiency in the institutional DD cutoff point with the need to find a better threshold through a large multicenter prospective trial to minimize unnecessary CTPA scans and to improve patient safety.

Resistive exercise in astronauts on prolonged spaceflights provides partial protection against spaceflight-induced bone loss

Bone loss in astronauts during spaceflight may be a risk factor for osteoporosis, fractures and renal stone formation. We previously reported that the bisphosphonate alendronate, combined with exercise that included an Advanced Resistive Exercise Device (ARED), can prevent or attenuate group mean declines in areal bone mineral density (aBMD) measured soon after ~ 6-month spaceflights aboard the International Space Station (ISS). It is unclear however if the beneficial effects on postflight aBMD were due to individual or combined effects of alendronate and ARED. Hence, 10 additional ISS astronauts were recruited who used the ARED (ARED group) without drug administration using similar measurements in the previous study, i.e., densitometry, biochemical assays and analysis of finite element (FE) models. In addition densitometry data (DXA and QCT only) were compared to published data from crewmembers (n = 14-18) flown prior to in-flight access to the ARED (Pre-ARED). Group mean changes from preflight (± SD %) were used to evaluate effects of countermeasures as sequentially modified on the ISS (i.e., Pre-ARED vs. ARED; ARED vs. Bis+ARED). Spaceflight durations were not significantly different between groups. Postflight bone density measurements were significantly reduced from preflight in the Pre-ARED group. As previously reported, combined Bis+ARED prevented declines in all DXA and QCT hip densitometry and in estimates of FE hip strengths; increased the aBMD of lumbar spine; and prevented elevations in urinary markers for bone resorption during spaceflight. ARED without alendronate partially attenuated declines in bone mass but did not suppress biomarkers for bone resorption or prevent trabecular bone loss. Resistive exercise in the ARED group did not prevent declines in hip trabecular vBMD, but prevented reductions in cortical vBMD of the femoral neck, in FE estimate of hip strength for non-linear stance (NLS) and in aBMD of the femoral neck. We conclude that a bisphosphonate, when combined with resistive exercise, enhances the preservation of bone mass because of the added suppression of bone resorption in trabecular bone compartment not evident with ARED alone.

P5000Wnt/b-catenin signalling drives angiotensin II induced cardiac fibrosis via WISP-1

Background

Myocardial infarction (MI) and hypertension lead to myocardial injury, which induces negative remodelling and cardiac fibrosis. Cardiac fibrosis, which involves inflammatory cell infiltration and myofibroblast activation, causes worldwide mortality and morbidity. In response to MI or hypertension induced by prolonged angiotensin II (AngII) exposure, activated myofibroblasts produce extracellular matrix proteins. However, if unchecked, excessive collagen deposition occurs leading to myocardial stiffening, heart failure and arrhythmias.

Purpose

The underlying mechanisms leading to pathological collagen deposition are not fully elucidated. There is debate regarding the involvement of the Wnt signalling pathway and its product Wnt Inducible Signalling pathway protein-1 (WISP-1) in cardiac fibrosis. Therefore, this project aimed to investigate the interaction of AngII and the Wnt/β-catenin signalling pathway in cardiac fibrosis.

Methods

The effect of AngII (100nM) on collagen levels in human cardiac fibroblasts was investigated in vitro (data expressed as fold change from control ± SEM). In vivo experiments (n=6–8) determined the involvement of the Wnt/b-catenin pathway, specifically WISP-1, in response to AngII infusion (500ng/kg/min) for 4 weeks (Apolipoprotein E−/−/WISP-1+/+ vs. ApolipoproteinE−/−/WISP-1−/− mice on a high-fat diet, data expressed as mean positive pixel % ± SEM).

Results

AngII significantly increased collagen type 1 protein levels produced by human cardiac fibroblasts (2.94±0.75 vs 1±0, p<0.05). Inhibition of Wnt/b-catenin signalling with 25nM iCRT14 significantly suppressed AngII-induced collagen levels (0.46±0.07 vs. 1±0, p<0.05). As expected, AngII infusion significantly induced hypertension in all mice. Immunohistochemistry demonstrated type 1 collagen was markedly higher in AngII mice than control mice (1.07±0.27 vs. 0.29±0.06, p<0.05). However, in the absence of WISP-1, AngII did not enhance collagen type 1 levels. Further immunohistochemical analysis of murine hearts demonstrated that AngII infusion caused significant alterations in the Wnt/β-catenin signalling markers AXIN-2 (35±3.9 vs. 10.7±2.6 p<0.05) and PPAR-d (92±1.4 vs. 17.3±4.3 p<0.05). This effect was reduced by WISP-1 deletion. Furthermore, AngII-infusion disrupted N-cadherin junctions (0.55±0.08 vs. 0.29±0.02 p<0.05) suggesting modulation of cell-to-cell contacts and enhanced β-catenin signalling.

Conclusion

This study indicates that AngII enhances cardiac fibrosis via modulation of the Wnt signalling pathway, in part via WISP-1. Further delineation of this interaction may lead to the use of Wnt/β-catenin or WISP-1 inhibitors to suppress myocardial injury induced cardiac fibrosis in post-MI or hypertensive patients.

Acknowledgement/Funding

Elizabeth Blackwell Institute, British Heart Foundation

Production effects of feeding extruded soybean meal to early-lactation dairy cows

The objective of this experiment was to evaluate productive and reproductive effects of replacing solvent-extracted soybean meal (SSBM) with extruded soybean meal (ESBM) in a total mixed ration for early-lactation dairy cows. Thirty-four Holstein cows (12 primiparous and 22 multiparous) were used in a randomized complete block design experiment with 17 cows per treatment. Feeding was ad libitum for 5 to 10% refusals. A fresh-cow diet was fed the first 21 d in milk followed by a lactation diet from 22 to 60 d in milk. Milk and dry matter intake data were collected throughout the experiment, and samples were collected for blood chemistry and amino acid profile, nutrient digestibility, nitrogen utilization, and enteric methane emission using the GreenFeed system (C-Lock Inc., Rapid City, SD). Dry matter intake, milk yield, and feed efficiency were not different between SSBM and ESBM. Energy-corrected milk yield and efficiency were also not different between diets. Diet had no effect on milk composition, except that milk true protein yield was decreased by ESBM. Enteric methane emission, yield, and intensity were not different between SSBM and ESBM. Because of its greater fat content, ESBM triggered expected changes in milk fatty acid (FA) profile: decreased sum of C16, saturated, and odd- and branched-chain FA and increased sum of preformed FA, polyunsaturated, and trans FA. The ESBM diet increased or tended to increase some essential amino acids in plasma. In this study, ESBM did not affect dry matter intake and did not improve lactational performance or onset of ovarian function in early-lactation dairy cows, and it decreased milk protein yield, possibly due to greater unsaturated FA intake compared with SSBM.

Use of stent retriever for treatment of iatrogenic intracranial vasospasm

Cerebral vasospasm is a source of morbidity and mortality, not only associated with aneurysmal subarachnoid hemorrhage (SAH) but also with endovascular procedures. Treatment of vasospasm associated with SAH include trans-luminal balloon angioplasty and intra-arterial delivery of vasodilator medications. We present a case report of a patient who underwent a mechanical thrombectomy for stroke and suffered from vasospasm. This severe flow-limiting vasospasm was successfully treated with the Trevo stent device. Although stent retrievers have become more widespread for thrombectomy, vasospasm treatment has not been often described in the literature. Further study is needed to determine if this is a viable technique for treating resistant vasospasm.

The Success and Evolution of a Urological "Boot Camp" for Newly Appointed UK Urology Registrars: Incorporating Simulation, Nontechnical Skills and Assessment

BACKGROUND

Urological training has dramatically changed in recent years. Training durations are shorter and a drive toward consultant led care has reduced trainees experience. Within the UK, approximately 50 registrars annually embark on a 5-year Urology training programme, with variable levels of basic urological experience.

OBJECTIVE

To describe a simulation programme aimed at delivering the knowledge and skills necessary to safely and effectively start working as a registrar in Urology by intensive training with a 1:1 faculty to delegate ratio.

DESIGN, SETTING, AND PARTICIPANTS

Our course content mirrors the UK training syllabus for junior Urology registrars. We delivered 8 modules over a 4-day programme with a fifth day of assessments. Delegates level of urological knowledge, operative competency and confidence pre-, immediately post-training and at 3-months postcourse were assessed. Objective delegate and faculty feedback was also collected. Technical skills modules include; inguinoscrotal surgery, ureteroscopy, transurethral resection, urodynamics, and Botox administration as well as basic reconstructive and laparoscopic operative skills. "Nontechnical" skills included simulated ward round, out-patient, and emergency scenarios.

RESULTS

Feedback from delegates and faculty members has been overwhelmingly positive. We have used this feedback to tailor the content of the course for following years. An increased knowledge level (based on mean examination scores [precourse 55.5%, postcourse 70.1%]) and operative competency was observed in all skills assessed (transurethral resection of the prostate, transurethral resection of bladder tumor, Ureteroscopy, laparoscopic skills, and instrument assembly). Operative confidence was increased immediately and at 3-months postcourse.

CONCLUSIONS

Our "boot camp" course provides a realistic introduction and foundation to begin Urological practice. Being delivered at the beginning of the training scheme, prior to intensive patient exposure, registrars are in an optimum position to develop their newly acquired knowledge and skills to enhance training and intends to improve patient safety and satisfaction.

N-acetyl Cysteine Coated Gallium Particles Demonstrate High Potency against Pseudomonas aeruginosa PAO1

Nosocomial infections pose serious health concerns with over 2 million reported annually in the United States. Many of these infections are associated with bacterial resistance to antibiotics and hence, alternative treatments are critically needed. The objective of this study was to assess the antimicrobial efficacy of a gallium (Ga)-based particle coated with N-Acetyl Cysteine (Ga-NAC) against Pseudomonas aeruginosa PAO1. Our studies showed the Minimum Inhibitory Concentration (MIC) of PAO1 treated with Ga-NAC was 1 µg/mL. Cytotoxicity of Ga-NAC against multiple cell lines was determined with no cytotoxicity observed up to concentrations of 2000 µg/mL (metal concentration), indicating a high therapeutic window. To elucidate potential antibacterial modes of action, Inductively Coupled Plasma—Mass Spectrometry (ICP-MS), infrared spectroscopy, and atomic force microscopy (AFM) were used. The results suggest improved Ga³⁺ interaction with PAO1 through Ga-NAC particles. No significant change in cell membrane chemistry or roughening was detected. As cell membrane integrity remained intact, the antimicrobial mode of action was linked to cellular internalization of Ga and subsequent iron metabolic disruption. Furthermore, Ga-NAC inhibited and disrupted biofilms seen with crystal violet assay and microscopy. Our findings suggest the Ga-NAC particle can potentially be used as an alternative to antibiotics for treatment of Pseudomonas aeruginosa infections.

Silica-quaternary ammonium "Fixed-Quat" nanofilm coated fiberglass mesh for water disinfection and harmful algal blooms control

Intensification of pollution loading worldwide has promoted an escalation of different types of disease-causing microorganisms, such as harmful algal blooms (HABs), instigating detrimental impacts on the quality of receiving surface waters. Formation of unwanted disinfection by-products (DBPs) resulting from conventional disinfection technologies reveals the need for the development of new sustainable alternatives. Quaternary Ammonium Compounds (QACs) are cationic surfactants widely known for their effective biocidal properties at the ppm level. In this study, a novel silica-based antimicrobial nanofilm was developed using a composite of silica-modified QAC (Fixed-Quat) and applied to a fiberglass mesh as an active surface via sol-gel technique. The synthesized Fixed-Quat nanocoating was found to be effective against E. coli with an inactivation rate of 1.3 × 10^-3 log reduction/cm min. The Fixed-Quat coated fiberglass mesh also demonstrated successful control of Microcystis aeruginosa with more than 99% inactivation after 10 hr of exposure. The developed antimicrobial mesh was also evaluated with wild-type microalgal species collected in a water body experiencing HABs, obtaining a 97% removal efficiency. Overall, the silica-functionalized Fixed-Quat nanocoating showed promising antimicrobial properties for water disinfection and HABs control, while decreasing concerns related to DBPs formation and the possible release of toxic nanomaterials into the environment.