Baked milk and egg diets revisited

Most children with milk and egg allergy are nonreactive to modified forms of milk and egg in bakery products such as muffins because of conformational changes in proteins. These baked milk (BM) and baked egg (BE) diets have become commonplace in the management of milk and egg allergy, respectively. Current laboratory- and skin test-based diagnostic approaches remain limited in their ability to predict BM/BE tolerance, resulting in various approaches to introduce these foods. One approach to introduce BM/BE is to offer a medically supervised oral food challenge and then advise dietary introduction of baked products for children who have tolerance. Another approach is adapted from a home-based protocol of graded ingestion of BM or BE originally intended for non-IgE mediated allergy, often referred to as a "ladder." The ladder advises home ingestion of increasing amounts of BM or BE. For children who have allergy to BM or BE, the ladder is essentially oral immunotherapy, although not always labeled or recognized as such. Risk assessment and education of patients suitable for home introduction are essential. A home approach that may be called a ladder can also be used to escalate diets after demonstrated tolerance of baked forms by introducing lesser cooked forms of milk or egg after tolerating BM or BE. A randomized controlled trial provided clear evidence that baked diets can hasten the resolution of IgE-mediated milk allergy. Moreover, BM/BE foods have an emerging role in the treatment of non-IgE-mediated allergy. There is tangential evidence for BM and BE diets in the prevention of IgE-mediated allergy.

Effects of transcranial direct current stimulation and transcranial random noise stimulation on working memory and task-related EEG in major depressive disorder

OBJECTIVE

To compare effects of transcranial direct current stimulation (tDCS) and transcranial random noise stimulation with a direct-current offset (tRNS + DC-offset) on working memory (WM) performance and task-related electroencephalography (EEG) in individuals with Major Depressive Disorder (MDD).

METHODS

Using a sham-controlled, parallel-groups design, 49 participants with MDD received either anodal tDCS (N = 16), high-frequency tRNS + DC-offset (N = 16), or sham stimulation (N = 17) to the left dorsolateral prefrontal cortex (DLPFC) for 20-minutes. The Sternberg WM task was completed with concurrent EEG recording before and at 5- and 25-minutes post-stimulation. Event-related synchronisation/desynchronisation (ERS/ERD) was calculated for theta, upper alpha, and gamma oscillations during WM encoding and maintenance.

RESULTS

tDCS significantly increased parieto-occipital upper alpha ERS/ERD during WM maintenance, observed on EEG recorded 5- and 25-minutes post-stimulation. tRNS + DC-offset did not significantly alter WM-related oscillatory activity when compared to sham stimulation. Neither tDCS nor tRNS + DC-offset improved WM performance to a significantly greater degree than sham stimulation.

CONCLUSIONS

Although tDCS induced persistent effects on WM-related oscillatory activity, neither tDCS nor tRNS + DC-offset enhanced WM performance in MDD.

SIGNIFICANCE

This reflects the first sham-controlled comparison of tDCS and tRNS + DC-offset in MDD. These findings directly contrast with evidence of tRNS-induced enhancements in WM in healthy individuals.

Cochlear implantation in advanced otosclerosis: utility of pre-operative radiological assessment in predicting intra-operative difficulty and final electrode position

OBJECTIVE

This study aimed to determine if pre-operative radiological scoring can reliably predict intra-operative difficulty and final cochlear electrode position in patients with advanced otosclerosis.

METHOD

A retrospective cohort study of advanced otosclerosis patients who underwent cochlear implantation (n = 48, 52 ears) was compared with a larger cohort of post-lingually deaf adult patients (n = 1414) with bilateral hearing loss and normal cochlear anatomy. Pre-operative imaging for advanced otosclerosis patients and final electrode position were scored and correlated with intra-operative difficulty and speech outcomes.

RESULTS

Advanced otosclerosis patients benefit significantly from cochlear implantation. Mean duration of deafness was longer in the advanced otosclerosis group (19.5 vs 14.3 years; p < 0.05).

CONCLUSION

Anatomical changes in advanced otosclerosis can result in increased difficulty of surgery. Evidence of pre-operative cochlear luminal changes was associated with intra-operative difficult insertion and final non-scala tympani position. Nearly all electrodes implanted in the advanced otosclerosis cohort were peri-modiolar. No reports of facial nerve stimulation were observed.

Scientific document development standards for the society of cardiovascular computed tomography (SCCT): A statement from the SCCT Guidelines Committee

The Society of Cardiovascular Computed Tomography (SCCT) is an international community of physicians, scientists and technologists advocating for research, education, and clinical excellence in the use of cardiovascular computed tomography (CCT). SCCT members are committed to improving health outcomes through effective use of CCT. The SCCT routinely authors, endorses, and jointly collaborates on scientific documents that reflect the best available evidence and expert consensus supported in practice of CCT. This paper outlines SCCT's methodology for developing scientific documents. It was formulated by members of the SCCT Guidelines Committee and approved by the SCCT Board of Directors.

Pathophysiology of bradykinin and histamine mediated angioedema

Angioedema is characterized by swelling localized to the subcutaneous and submucosal tissues. This review provides an overview of angioedema, including the different types, triggers, and underlying pathophysiologic mechanisms. Hereditary and acquired angioedema are caused by dysregulation of the complement and kinin pathways. In contrast, drug-induced and allergic angioedema involve the activation of the immune system and release of vasoactive mediators. Recent advances in the understanding of the pathophysiology of angioedema have led to the development of targeted therapies, such as monoclonal antibodies, bradykinin receptor antagonists, and complement inhibitors, which promise to improve clinical outcomes in patients with this challenging condition. To accurately diagnose and manage angioedema, an understanding of this condition's complex and varied pathophysiology is both necessary and critical.

Clinical Pathway for Coronary Atherosclerosis in Patients Without Conventional Modifiable Risk Factors: JACC State-of-the-Art Review

Reducing the incidence and prevalence of standard modifiable cardiovascular risk factors (SMuRFs) is critical to tackling the global burden of coronary artery disease (CAD). However, a substantial number of individuals develop coronary atherosclerosis despite no SMuRFs. SMuRFless patients presenting with myocardial infarction have been observed to have an unexpected higher early mortality compared to their counterparts with at least 1 SMuRF. Evidence for optimal management of these patients is lacking. We assembled an international, multidisciplinary team to develop an evidence-based clinical pathway for SMuRFless CAD patients. A modified Delphi method was applied. The resulting pathway confirms underlying atherosclerosis and true SMuRFless status, ensures evidence-based secondary prevention, and considers additional tests and interventions for less typical contributors. This dedicated pathway for a previously overlooked CAD population, with an accompanying registry, aims to improve outcomes through enhanced adherence to evidence-based secondary prevention and additional diagnosis of modifiable risk factors observed.

ZIF-8 Pellets as a Robust Material for Hydrogen Cryo-Adsorption Tanks

Cryoadsorption on the inner surface of porous materials is a promising solution for safe, fast, and reversible hydrogen storage. Within the class of highly porous metal-organic frameworks, zeolitic imidazolate frameworks (ZIFs) show high thermal, chemical, and mechanical stability. In this study, we selected ZIF-8 synthesized mechanochemically by twin-screw extrusion as powder and pellets. The hydrogen storage capacity at 77 K and up to 100 bar has been analyzed in two laboratories applying three different measurement setups showing a high reproducibility. Pelletizing ZIF-8 increases the packing density close to the corresponding value for a single crystal without loss of porosity, resulting in an improved volumetric hydrogen storage capacity close to the upper limit for a single crystal. The high volumetric uptake combined with a low and constant heat of adsorption provides ca. 31 g of usable hydrogen per liter of pellet assuming a temperature-pressure swing adsorption process between 77 K - 100 bar and 117 K - 5 bar. Cycling experiments do not indicate any degradation in storage capacity. The excellent stability during preparation, handling, and operation of ZIF-8 pellets demonstrates its potential as a robust adsorbent material for technical application in pilot- and full-scale adsorption vessel prototypes.

Pancreatic Adenocarcinoma: Real World Evidence of Care Delivery in AccessHope Data

BACKGROUND

Pancreatic adenocarcinoma is an aggressive disease and the delivery of comprehensive care to individuals with this cancer is critical to achieve appropriate outcomes. The identification of gaps in care delivery facilitates the design of interventions to optimize care delivery and improve outcomes in this population.

METHODS

AccessHope™ is a growing organization that connects oncology subspecialists with treating providers through contracts with self-insured employers. Data from 94 pancreatic adenocarcinoma cases (August 2019-December 2022) in the AccessHope dataset were used to describe gaps in care delivery.

RESULTS

In all but 6% of cases, the subspecialist provided guideline-concordant recommendations anticipated to improve outcomes. Gaps in care were more pronounced in patients with non-metastatic pancreatic cancer. There was a significant deficiency in germline testing regardless of the stage, with only 59% of cases having completed testing. Only 20% of cases were receiving palliative care or other allied support services. There was no difference in observed care gaps between patients receiving care in the community setting vs. those receiving care in the academic setting.

CONCLUSIONS

There are significant gaps in the care delivered to patients with pancreatic adenocarcinoma. A concurrent subspecialist review has the opportunity to identify and address these gaps in a timely manner.

Profiling novel lateral gene transfer events in the human microbiome

Lateral gene transfer (LGT) is an important mechanism for genome diversification in microbial populations, including the human microbiome. While prior work has surveyed LGT events in human-associated microbial isolate genomes, the scope and dynamics of novel LGT events arising in personal microbiomes are not well understood, as there are no widely adopted computational methods to detect, quantify, and characterize LGT from complex microbial communities. We addressed this by developing, benchmarking, and experimentally validating a computational method (WAAFLE) to profile novel LGT events from assembled metagenomes. Applying WAAFLE to >2K human metagenomes from diverse body sites, we identified >100K putative high-confidence but previously uncharacterized LGT events (~2 per assembled microbial genome-equivalent). These events were enriched for mobile elements (as expected), as well as restriction-modification and transport functions typically associated with the destruction of foreign DNA. LGT frequency was quantifiably influenced by biogeography, the phylogenetic similarity of the involved taxa, and the ecological abundance of the donor taxon. These forces manifest as LGT networks in which hub species abundant in a community type donate unequally with their close phylogenetic neighbors. Our findings suggest that LGT may be a more ubiquitous process in the human microbiome than previously described. The open-source WAAFLE implementation, documentation, and data from this work are available at http://huttenhower.sph.harvard.edu/waafle.

Reliability of radiologists' first impression when interpreting a screening mammogram

Previous studies showed that radiologists can detect the gist of an abnormality in a mammogram based on a half-second image presentation through global processing of screening mammograms. This study investigated the intra- and inter-observer reliability of the radiologists' initial impressions about the abnormality (or "gist signal"). It also examined if a subset of radiologists produced more reliable and accurate gist signals. Thirty-nine radiologists provided their initial impressions on two separate occasions, viewing each mammogram for half a second each time. The intra-class correlation (ICC) values showed poor to moderate intra-reader reliability. Only 13 radiologists had an ICC of 0.6 or above, which is considered the minimum standard for reliability, and only three radiologists had an ICC exceeding 0.7. The median value for the weighted Cohen's Kappa was 0.478 (interquartile range = 0.419-0.555). The Mann-Whitney U-test showed that the "Gist Experts", defined as those who outperformed others, had significantly higher ICC values (p = 0.002) and weighted Cohen's Kappa scores (p = 0.026). However, even for these experts, the intra-radiologist agreements were not strong, as an ICC of at least 0.75 indicates good reliability and the signal from none of the readers reached this level of reliability as determined by ICC values. The inter-reader reliability of the gist signal was poor, with an ICC score of 0.31 (CI = 0.26-0.37). The Fleiss Kappa score of 0.106 (CI = 0.105-0.106), indicating only slight inter-reader agreement, confirms the findings from the ICC analysis. The intra- and inter-reader reliability analysis showed that the radiologists' initial impressions are not reliable signals. In particular, the absence of an abnormal gist does not reliably signal a normal case, so radiologists should keep searching. This highlights the importance of "discovery scanning," or coarse screening to detect potential targets before ending the visual search.

Relationship between in feed drugs, antibiotics and organic enrichment in marine sediments at Canadian Atlantic salmon aquaculture sites

The presence of in-feed anti-sea lice drugs and their relationship with organic enrichment is poorly understood in sediment surrounding salmon farms. Using data from an aquaculture monitoring program (2018-2020), we describe this relationship at ten sites in four Canadian provinces. Three anti-sea lice pesticides (lufenuron, teflubenzuron, emamectin benzoate and metabolite desmethyl emamectin benzoate), and one antibiotic (oxytetracycline) were detected. Concentrations were often below limits of quantification. Values are also lower than those reported in other aquaculture salmon-producing countries. Highest concentrations, along with organic enrichment, were observed ~200 m of cages with lower concentrations detected up to 1.5 km away. Most samples had at least two drugs present: 75.2 % (British Columbia), 91.4 % (Newfoundland), and 54.8 % (New Brunswick/Nova Scotia) highlighting the potential for cumulative effects. Emamectin benzoate and oxytetracycline were detected four and three years respectively after last known treatments, demonstrating the need for research on overall persistence of compounds.

Development and validation of a remote monitoring tool for assessment of mild, moderate, and severe infections in Inflammatory Bowel Disease

BACKGROUND

Immunomodulators and biologicals are cornerstones in the management of Inflammatory Bowel Disease (IBD), but are associated with increased risk of infections. Post-marketing surveillance registries are pivotal to assess this risk, yet mainly focus on severe infections. Data on the prevalence of mild and moderate infections are scarce. We developed and validated a remote monitoring tool for real-world assessment of infections in IBD patients.

METHODS

A 7-item Patient-Reported Infections Questionnaire (PRIQ) covering 15 infection categories was developed with a 3-month recall period. Infection severity was defined as mild (self-limiting or topical treatment), moderate (oral antibiotics, antivirals or antifungals) or severe (hospitalisation or IV treatment). Comprehensiveness and comprehensibility were ascertained through cognitive interviewing of 36 IBD outpatients. After implementation in telemedicine platform myIBDcoach, a prospective multicentre cohort study was performed between June 2020 and June 2021 in 584 patients to assess diagnostic accuracy. Events were cross-checked with GP and pharmacy data (gold standard). Agreement was evaluated using linear-weighted kappa with cluster-bootstrapping to account for within-patient level correlation.

RESULTS

Patient understanding was good and interviews did not result in reduction of PRIQ-items. During validation, 584 IBD patients (57.8% female, mean age 48.6 [SD: 14.8], disease duration 12.6 years [SD: 10.9]) completed 1386 periodic assessments, reporting 1626 events. Linear-weighted kappa for agreement between PRIQ and gold standard was 0.92 (95%CI 0.89-0.94). Sensitivity and specificity for infection (y/n) were 93.9% (95%CI 91.8-96.0) and 98.5% (95%CI 97.5-99.4).

CONCLUSIONS

The PRIQ is a valid and accurate remote monitoring tool to assess infections in IBD patients, providing means to personalise medicine based on adequate benefit-risk assessments.

Diphenhydramine: Time to Move on?

Diphenhydramine is one of the most widely available, longest-used antihistamine medications but has many side effects including sedation and risk of toxicity in overdose including cardiac toxicity. It is frequently inappropriately used when newer, more favorable antihistamine medications are available. Second-generation antihistamines are also widely available and affordable, with many of the same desired effects as diphenhydramine and fewer, if any, of the undesirable side effects. Because of the negative side effects and wide availability of alternative antihistamine medications, it is definitively time to move on from diphenhydramine.

Changes in Doctor-Patient Relationships in China during COVID-19: A Text Mining Analysis

Doctor-patient relationships (DPRs) in China have been straining. With the emergence of the COVID-19 pandemic, the relationships and interactions between patients and doctors are changing. This study investigated how patients' attitudes toward physicians changed during the pandemic and what factors were associated with these changes, leading to insights for improving management in the healthcare sector. This paper collected 58,600 comments regarding Chinese doctors from three regions from the online health platform Good Doctors Online (haodf.com, accessed on 13 October 2022). These comments were analyzed using text mining techniques, such as sentiment and word frequency analyses. The results showed improvements in DPRs after the pandemic, and the degree of improvement was related to the extent to which a location was affected. The findings also suggest that administrative services in the healthcare sector need further improvement. Based on these results, we summarize relevant recommendations at the end of this paper.

Surgical treatment of pelvic organ prolapse in women aged ≥75 years in Hong Kong: a multicentre retrospective study

INTRODUCTION

Pelvic organ prolapse (POP) is common among older women. With the increasing lifespan and emphasis on quality of life worldwide, older women increasingly prefer surgical treatment for POP. We reviewed the surgical treatment of POP in older women to characterise its safety, effectiveness, and the type most often selected.

METHODS

This multicentre, retrospective study was conducted at four hospitals between 2013 and 2018. Included patients were aged ≥75 years and had undergone POP surgery. We compared patient demographic characteristics, POP severity, and surgical outcomes between reconstructive and obliterative surgeries; these comparisons were also made among vaginal hysterectomy plus pelvic floor repair (VHPFR), transvaginal mesh surgery (TVM), vaginal hysterectomy (VH) plus colpocleisis, and colpocleisis alone.

RESULTS

In total, 343 patients were included; 84.3% and 15.7% underwent reconstructive and obliterative surgeries, respectively. Overall, 246 (71.7%), 43 (12.5%), 20 (5.8%), and 34 (9.9%) patients underwent VHPFR, TVM, VH plus colpocleisis, and colpocleisis alone, respectively. Patients who were older (81.9 vs 79.6 y; P=0.001), had vault prolapse (38.9% vs 3.5%; P<0.001), and had medical co-morbidities (37% vs 4.8%; P<0.001) chose obliterative surgery more frequently than reconstructive surgery. Obliterative surgeries had shorter operative time (73.5 min vs 107 min; P<0.001) and fewer surgical complications (9.3% vs 28.0%; P=0.003). Vaginal hysterectomy plus pelvic floor repair had the highest rate of surgical complications (most were minor), while colpocleisis alone had the lowest rate (30.1% vs 8.8%; P=0.01).

CONCLUSIONS

Pelvic organ prolapse surgeries were safe and effective for older women. Colpocleisis may be appropriate as primary surgery for fragile older women.

Spectroscopy of the frustrated quantum antiferromagnet Cs2CuCl4

We investigate the electronic structure of Cs₂CuCl₄, a material discussed in the framework of a frustrated quantum antiferromagnet, by means of resonant inelastic x-ray scattering (RIXS) and density functional theory (DFT). From the non-dispersive highly localizedddexcitations, we resolve the crystal field splitting of the Cu²⁺ions in a strongly distorted tetrahedral coordination. This allows us to model the RIXS spectrum within the crystal field theory (CFT), assign theddorbital excitations and retrieve experimentally the values of the crystal field splitting parametersD_q,D_sandD_τ. The electronic structure obtainedab-initioagrees with the RIXS spectrum and modelled by CFT, highlighting the potential of combined spectroscopic, cluster and DFT calculations to determine the electronic ground state of complex materials.

Assessing trace-elements as indicators of marine finfish aquaculture across three distinct Canadian coastal regions

Several trace-elements have been identified as indicators of finfish aquaculture organic enrichment. In this study, sediment sampling at finfish farms was completed as part of an Aquaculture Monitoring Program in three distinct Canadian regions. Despite diverse datasets, multivariate analyses show a consistent clustering of known direct (Cu and Zn) and indirect (Cd, Mo and U) tracers of aquaculture activities with sediment organic matter (OM) and/or total dissolved sulfides concentrations. OM content was also a predictor of Cu, Zn, Mo and U concentrations according to decision tree analyses. Distance from cages did not emerge as a strong driver of differences among sampling points; however, a tendency towards negative associations is clear especially for Zn. Enriched stations as determined after geochemical normalization were mostly localized within 150 m of net-pens. Selected trace-elements (in particular Zn) can be useful indicators of aquaculture organic enrichment in different ecosystems and valuable tools for monitoring programs.

Towards MOFs' mass market adoption: MOF Technologies' efficient and versatile one-step extrusion of shaped MOFs directly from raw materials

Metal Organic Frameworks (MOFs) offer unparalleled physical and sorption properties due to their chemical tunability and unmatched porosity. MOFs are consequently envisaged to play a key role in commercial gas storage and separation applications. However, it is essential to tackle their current market entry barriers, if mainstream adoption is to be realised. MOF Technologies is a pioneer in MOF commercialisation and has developed innovative solutions with unprecedented efficiency to bring these materials to market. A continuous, versatile and sustainable one-step production method of MOFs in shaped form is demonstrated for the first time. Its advantages for large-scale production and mass customisation are exemplified and validated with performance evaluation under realistic operating conditions.

A review of the Turned-down Onto Pericapsular-tissue Hemisectioned Amputated Toe (TOPHAT) flap for wound coverage during ray amputations of the toes

INTRODUCTION

Exposure of the adjacent Metatarsal-Phalangeal Joint (MTPJ) commonly occurs after application of Topical Negative Pressure Wound Therapy (TNPWT) for a ray amputation wound. This is due to mechanical soft tissue erosion or trauma to the adjacent digital artery from direct pressure effect. This results in toe gangrene requiring a ray amputation and ultimately a larger wound bed. We describe the use of the Turned-down Onto Pericapsular-tissue Hemisectioned Amputated Toe (TOPHAT) flap - a filleted toe flap to protect the adjacent MTPJ capsule combined with a novel Negative Pressure Wound Therapy with instillation and dwell-time (NPWTi-d) dressing technique. The flap protects the adjacent joint capsule and reduces the wound burden whilst allowing the wound to benefit from TNPWT, thereby accelerating wound healing.

MATERIAL AND METHODS

A retrospective review was conducted of patients with toe gangrene requiring ray amputation that underwent the TOPHAT flap on in our institution from 2019 and 2020. Complications such as wound dehiscence, hematoma, flap necrosis and secondary infection were recorded. Other outcomes recorded were time taken to final skin grafting and time taken for complete wound epithelialization.

RESULTS

9 patients underwent treatment with the TOPHAT flap. 2 patients had flap necrosis. 7 patients progressed to definitive skin coverage with skin grafting. One patient subsequently had progressive arterial disease despite successful skin grafting and required above knee amputation. The mean time to final skin grafting and complete wound epithelialization was 49.5 days and 107.5 days respectively. All patients were satisfied with the outcomes and were able to return to their pre-morbid function.

CONCLUSIONS

The TOPHAT flap has a consistent vascular supply that provides durable soft tissue coverage. It is a robust and easily reproducible technique to accelerate wound healing after ray amputations even in patients with peripheral vascular disease.

POS1256 SINGLE DOSE TOCILIZUMAB PHARMACOKINETICS IN GLUCOCORTICOID PRE-TREATED COVID-19 PATIENTS DURING CYTOKINE STORM SYNDROME HYPERINFLAMMATORY EPISODE: LESS IS MORE

Background:

The cytokine storm syndrome (CSS) associated with COVID-19 pneumonia occurs in up to 20% of the admitted patients causing high morbidity and mortality [1]. In the COVID High-intensity Immunosuppression in Cytokine storm syndrome (CHIC) study [1] we reported that CSS patients, who despite high-dose methylprednisolone (MP) treatment still showed severe respiratory deterioration, received subsequent single dose tocilizumab (TCZ) treatment. Our clinical experience with TCZ, every 4 weeks in RA, where a pre-dose serum concentration of > 1 µg/ml is sufficient to block all interleukin (IL)-6 receptors and thereby induce and maintain clinical remission, prompted further investigation of TCZ pharmacokinetics in patients with COVID-19 CSS [1,2].

Objectives:

In this pharmacokinetic study we investigated the clinical-pharmacokinetic rationale for a single TCZ dose in a subset of COVID19 induced CSS patients.

Methods:

Patients with COVID-19-associated CSS, defined as rapid respiratory deterioration plus at least two biomarker elevations (C-reactive protein (CRP) >100 mg/L; ferritin >900 μg/L; D-dimers >1500 μg/L), received per protocol high-dose intravenous MP for 5 consecutive days. If the respiratory condition had not improved sufficiently, TCZ (8 mg/kg, max. 800 mg) single infusion was added on or after day 2[1]. TCZ serum samples were drawn at TCZ day 1, 3 and 10 to assess TCZ serum concentrations with a validated ELISA-method. A nonlinear-mixed effects model was developed based on all concentration time data to characterise TCZ pharmacokinetics (NONMEM). Subsequently individual pharmacokinetic parameters (AUC0-inf, Cmax, time above 1 µg/ml) were estimated and TCZ concentration-time observations were plotted against the individual predicted concentrations to visualize the complete TCZ concentration-time curve.

Results:

In total, 34 patients with COVID19 induced CSS still showing clinical deterioration upon MP treatment received TCZ per protocol [mean (SD) age: 62 (12) years, 22% female, baseline mean (SD) bodyweight: 87 (17) kg, CRP: 108 (833) mmol/L, ferritin: 1653 (911) µg/L, D-dimers 4462 (7272) µg/L]. TCZ clearance was described by a homogeneous population-kinetics model yielding 87 serum samples. TCZ serum concentrations followed a biphasic course [Distribution volume 5.0 L (3.3-7.3), Area Under the Curve0-∞1st dose (682 (397-913) mg/L*days), Cmax 137 mg/L (88 – 199), half-life (linear) 3.5 days (2.3-4.1)]. In all patients, TCZ serum concentrations remained above the theoretical maximum IL-6 receptor occupancy concentration of 1 µg/ml for at least 12 days, depicted in Figure 1.

Figure 1.

Predicted concentration-time profiles after single dose tocilizumab in 34 methylpred-nisolone pretreated patients with COVID-19 induced cytokine storm syndrome. Dashed line: maximum IL-6 receptor occupancy concentration 1 µg/ml

Conclusion:

Based on our study results on the pharmacokinetics of TCZ in patients with severe COVID-19 induced CSS we conclude that the clearance of TCZ is faster compared to RA-patients at steady state. However, our observations indicate that a single dose of tocilizumab in CSS-patients is enough to cover IL-6 mediated hyperinflammation. Restricting TCZ to a single dosage can prevent overtreatment, drug shortage and saves costs, while still maintaining efficacy, as most patients will have overcome their hyperinflammatory period of the CSS after 10-14 days.

References:

[1]Ramiro S. Mostard R.L.M. et al. Historically controlled comparison of glucocorticoids with or without tocilizumab versus supportive care only in patients with COVID-19-associated cytokine storm syndrome: results of the CHIC study. Ann Rheum Dis 2020;79(9):1143-1151.

[2]Nishimoto N, Terao K et al. Mechanisms and pathologic significances in increase in serum interleukin-6 (IL-6) and soluble IL-6 receptor after administration of an anti IL-6 receptor antibody, tocilizumab, in patients with rheumatoid arthritis and Castleman disease. Blood. 2008;112:3959-3964.

Acknowledgements:

The authors are grateful to all patients, nurses and physicians who participated in this study.

Disclosure of Interests:

None declared

A Critical Review of the Time-Dependent Performance of Polymeric Pipeline Coatings: Focus on Hydration of Epoxy-Based Coatings

The barrier performance of organic coatings is a direct function of mass transport and long-term stability of the polymeric structure. A predictive assessment of the protective coating cannot be conducted a priori of degradation effects on transport. Epoxy-based powder coatings are an attractive class of coatings for pipelines and other structures because application processing times are low and residual stresses between polymer layers are reduced. However, water ingress into the polymeric network of these coatings is of particular interest due to associated competitive sorption and plasticization effects. This review examines common analytical techniques for identifying parameters involved in transport in wet environments and underscores the gaps in the literature for the evaluation of the long-term performance of such coating systems. Studies have shown that the extent of polymer hydration has a major impact on gas and ion permeability/selectivity. Thus, transport analyses based only on micropore filling (i.e., adsorption) by water molecules are inadequate. Combinatorial entropy of the glassy epoxy and water vapor mixture not only affects the mechanism of membrane plasticization, but also changes the sorption kinetics of gas permeation and causes a partial gas immobility in the system. However, diffusivity, defined as the product of a kinetic mobility parameter and a concentration-dependent thermodynamic parameter, can eventually become favorable for gas transport at elevated temperatures, meaning that increasing gas pressure can decrease selectivity of the membrane for gas permeation. On the other hand, reverse osmosis membranes have shown that salt permeation is sensitive to, among other variables, water content in the polymer and a fundamental attribute in ionic diffusion is the effective size of hydrated ions. In addition, external electron sources-e.g., cathodic protection potentials for pipeline structures-can alter the kinetics of this transport as the tendency of ions to dissociate increases due to electrostatic forces. Focusing primarily on epoxy-based powder coatings, this review demonstrates that service parameters such as humidity, temperature, and concentration of aggressive species can dynamically develop different transport mechanisms, each at the expense of others. Although multilayered coating systems decrease moisture ingress and the consequences of environmental exposure, this survey shows that demands for extreme operating conditions can pose new challenges for coating materials and sparse data on transport properties would limit analysis of the remaining life of the system. This knowledge gap impedes the prediction of the likelihood of coating and, consequently, infrastructure failures.

Fall incidents in nursing home residents: development of a predictive clinical rule (FINDER)

OBJECTIVES

To develop (part I) and validate (part II) an electronic fall risk clinical rule (CR) to identify nursing home residents (NH-residents) at risk for a fall incident.

DESIGN

Observational, retrospective case-control study.

SETTING

Nursing homes.

PARTICIPANTS

A total of 1668 (824 in part I, 844 in part II) NH-residents from the Netherlands were included. Data of participants from part I were excluded in part II.

PRIMARY AND SECONDARY OUTCOME MEASURES

Development and validation of a fall risk CR in NH-residents. Logistic regression analysis was conducted to identify the fall risk-variables in part I. With these, three CRs were developed (ie, at the day of the fall incident and 3 days and 5 days prior to the fall incident). The overall prediction quality of the CRs were assessed using the area under the receiver operating characteristics (AUROC), and a cut-off value was determined for the predicted risk ensuring a sensitivity ≥0.85. Finally, one CR was chosen and validated in part II using a new retrospective data set.

RESULTS

Eleven fall risk-variables were identified in part I. The AUROCs of the three CRs form part I were similar: the AUROC for models I, II and III were 0.714 (95% CI: 0.679 to 0.748), 0.715 (95% CI: 0.680 to 0.750) and 0.709 (95% CI: 0.674 to 0.744), respectively. Model III (ie, 5 days prior to the fall incident) was chosen for validation in part II. The validated AUROC of the CR, obtained in part II, was 0.603 (95% CI: 0.565 to 0.641) with a sensitivity of 83.41% (95% CI: 79.44% to 86.76%) and a specificity of 27.25% (95% CI 23.11% to 31.81%).

CONCLUSION

Medication data and resident characteristics alone are not sufficient enough to develop a successful CR with a high sensitivity and specificity to predict fall risk in NH-residents.

TRIAL REGISTRATION NUMBER

Not available.

A228 WHEN ASCITES & VARICEAL BLEEDING ARE NOT FROM CIRRHOSIS: A CASE OF MUTIPLE ARTERIOPORTAL FISTULAE CAUSING PORTAL HYPERTENSION

Background

Portal hypertension is usually due to increased resistance from cirrhosis. However, pressures can also be elevated due to increased flow.

Aims

To describe a peculiar case of non-cirrhotic portal hypertension.

Methods

A case report and literature review was performed.

Results

A 47-year-old previously well man presented with a 6 month history of rapidly progressive weight loss, ascites and variceal bleed. Workup ruled out common causes of primary liver disease. Initial imaging demonstrated a heterogenous liver, splenomegaly, ascites, patent hepatic/portal veins and multiple poorly defined low-density hepatic lesions with the largest measuring 2.1 cm. Transient elastography was 7.3 kPa (F1-mild fibrosis). At transjugular liver biopsy, hepatic venogram ruled out Budd-Chiari and hepatic vein pressure gradient was normal at 3–4 mmHg. Histology unfortunately showed hemangioma. A percutaneous liver biopsy suggested nodular regenerative hyperplasia, minimal fibrosis and mild cholestasis. Given worsening ascites, hyponatremia and 7 months of rapidly progressive decline, transjugular intrahepatic portosystemic shunt (TIPSS) was inserted. Intra-procedure, portal vein pressure was noted to be 51 mmHg, with a portosystemic gradient of 42 mmHg. Although numerous abdominal CT and MRI did not show AV shunting, ultrasound post-TIPSS showed hepatic pseudoaneurysms & arterioportal fistulae (APF). Direct angiogram showed numerous hepatic pseudoaneurysms and intrahepatic fistulae making embolization impossible. CT showed no evidence of pseudoaneurysms or fistulae outside of the liver. Workup for autoimmune rheumatological diseases and congenital telangiectatic syndromes were negative. Given the high pressures being directed through the new TIPSS, right heart failure is an ongoing concern.

APF are rarely encountered causes of presinusoidal portal hypertension, with communications most commonly arising from the hepatic (65%) & splenic arteries (11%) & the portal vein. Causes include traumatic (28%), iatrogenic (16%), vascular/telangiectatic malformations (15%), tumors (15%), aneurysms (14%) & congenital disease. Endovascular embolization can be used to treat single lesions. In complex cases with mulitple APF, surgery and/or liver transplantation may be required.

Conclusions

We report a rare case of non-cirrhotic portal hypertension due to increased flow rather than increased resistance secondary to APF.

Funding Agencies

None

Capturing accelerometer outputs in healthy volunteers under normal and simulated-pathological conditions using ML classifiers

Wearable devices offer a possible solution for acquiring objective measurements of physical activity. Most current algorithms are derived using data from healthy volunteers. It is unclear whether such algorithms are suitable in specific clinical scenarios, such as when an individual has altered gait. We hypothesized that algorithms trained on healthy population will result in less accurate results when tested in individuals with altered gait. We further hypothesized that algorithms trained on simulated-pathological gait would prove better at classifying abnormal activity. We studied healthy volunteers to assess whether activity classification accuracy differed for those with healthy and simulated-pathological conditions. Healthy participants (n=30) were recruited from the University of Leeds to perform nine predefined activities under healthy and simulated-pathological conditions. Activities were captured using a wrist-worn MOX accelerometer (Maastricht Instruments, NL). Data were analyzed based on the Activity-Recognition-Chain process. We trained a Neural-Network, Random-Forests, k-Nearest-Neighbors (k-NN), Support-Vector-Machines (SVM) and Naive Bayes models to classify activity. Algorithms were trained four times; once with `healthy' data, and once with `simulated-pathological data' for each of activity-type and activity-task classification. In activity-type instances, the SVM provided the best results; the accuracy was 98.4% when the algorithm was trained and then tested with unseen data from the same group of healthy individuals. Accuracy dropped to 52.8% when tested on simulated-pathological data. When the model was retrained with simulated-pathological data, prediction accuracy for the corresponding test set was 96.7%. Algorithms developed on healthy data are less accurate for pathological conditions. When evaluating pathological conditions, classifier algorithms developed using data from a target sub-population can restore accuracy to above 95%.

Interpretative characteristics and case features associated with the performances of radiologists in reading mammograms: A study from a non-screening population in Asia

AIMS

To explore radiologist characteristics and case features associated with diagnostic performances in cancer detection on mammograms in a South East Asian population.

METHODS

Fifty-three radiologists reported 60 mammographic examinations which consisted of 40 normal and 20 cancer-containing cases at the BREAST workshops. Radiologists were asked to examine each mammogram using the BIRADS on diagnostic monitors. Differences in reader characteristics and case features between correct and incorrect decisions were assessed separately for cancer and normal cases. Univariate and multivariate logistic regressions were applied to generate odds ratios (OR) for significant factors related to correct decisions.

RESULTS

Radiologists who spent ≥10 hours/week reporting mammograms had a higher possibility of detecting cancer lesions (OR = 1.6; P = 0.01). A higher rate of accuracy in reporting negative cases was associated with female radiologists (OR = 1.4; P = 0.002), radiologists who read ≤20 mammograms per week (OR = 1.5; P < 0.0001), had completed training course (OR = 1.7; P < 0.0001) or wore eyeglasses (OR = 1.4; P = 0.01). Cancer cases with breast density >50% (OR = 2.1; P < 0.0001), having abnormal lesions ≥9 mm (OR = 1.8; P < 0.0001), or displaying calcifications, a discrete mass or nonspecific density (OR = 1.6; P < 0.0001) were recorded with a higher detection rate by radiologists than other cases. Lesions located on the right breasts (OR = 1.8; P < 0.0001) or found in the lower inner, upper outer or mixed locations (OR = 2.7; P < 0.0001) were also recorded with a better diagnostic possibility compared with other lesions.

CONCLUSION

This work identified key features related to diagnostic accuracy of breast cancer on mammograms in a nonscreening population, which is helpful for developing appropriate strategies to improve breast cancer detectability of radiologists.

P2561Withdrawal of simulated obstructive sleep apnea partially reverses atrial arrhythmogenic substrate in rats

Background

Obstructive sleep apnea (OSA) is associated with structural alterations of the left atria (LA) and increased occurrence of atrial fibrillation (AF). Obstructive respiratory events lead to intermittent hypoxia (IH) and ineffective inspiration against the occluded upper airways, which result in intrathoracic and cardiac transmural pressure changes. Data on reversibility of LA-structural remodeling processes after withdrawal of OSA are still missing.

Objectives

Aim of the study was to develop a novel AF animal model mimicking intrathoracic pressure changes in addition to IH and to analyze the effect of OSA-withdrawal on atrial remodeling reversibility.

Method

In sedated rats (2% isoflurane), IH (n=9) was applied by intermittent increase in the respiratory dead volume. Standardized obstructive respiratory events were induced by defined intermittent negative upper airway pressure (INAP = inverse CPAP) applied via a customized mask connected to a negative pressure device (n=9). One minute of IH or INAP was followed by a rest period of nine minutes for four hours every second day. Rats with comparable anesthesia were used as controls (CTR). After three weeks, the animals were sacrificed. To analyze atrial structural remodeling reversibility, additional INAP-rats (n=5) were sacrificed after INAP-withdrawal of three weeks and compared to respective CTR (n=7).

Result

Blood pressure was not affected by IH or INAP. Intermittent desaturation and post-apneic hyperventilation were comparable in INAP- and IH-rats, but INAP-rats showed significantly higher breathing efforts during apneas compared to IH-rats. LA connexin43 (Cx43) protein expression assessed by quantitative immunofluorescence was reduced in both groups compared to CTR (0.77±0.07% in CTR vs. 0.45±0.06% in IH, p=0.02; CTR vs. 0.39±0.06% in INAP, p=0.005). However, LA interstitial fibrosis content (7.03±0.58% vs. CTR, p=0.01) and LA myocyte diameters (13.23±0.34μm vs. CTR, p=0.03) were increased in INAP-rats, but not in IH-rats. This was associated with longer inducible AF-durations in INAP-rats (11.65±4.43s vs. 0.72±0.33s in CTR, p=0.03) but not in IH-rats (1.28±0.33s vs. CTR, p=0.31). Three weeks of INAP-withdrawal (INAP-W) normalized interstitial fibrosis content (INAP-W vs. CTR, p=0.50) and LA-myocyte diameter (INAP-W vs. CTR, p=0.31). However, LA Cx43 protein expression remained low after three weeks of INAP withdrawal and inducible AF-episodes were still prolonged compared to respective CTR.

Conclusion

Application of INAP in rats mimics important components of OSA beyond IH and allows the study of an arrhythmogenic substrate in the atrium independent of the development of risk factors. In our model, withdrawal of INAP resulted in partial reversibility of structural LA remodeling but was not sufficient to abolish inducible AF-episodes completely. Future clinical studies are warranted to determine the anti-arrhythmic effect of isolated sleep apnea treatment in AF-patients.

Acknowledgement/Funding

Else Kröner-Fresenius-Stiftung, SFB-TRR219-M02/S-02