A 1 Ma sedimentary ancient DNA (sedaDNA) record of catchment vegetation changes and the developmental history of tropical Lake Towuti (Sulawesi, Indonesia)

Studying past ecosystems from ancient environmental DNA preserved in lake sediments (sedaDNA) is a rapidly expanding field. This research has mainly involved Holocene sediments from lakes in cool climates, with little known about the suitability of sedaDNA to reconstruct substantially older ecosystems in the warm tropics. Here, we report the successful recovery of chloroplast trnL (UAA) sequences (trnL-P6 loop) from the sedimentary record of Lake Towuti (Sulawesi, Indonesia) to elucidate changes in regional tropical vegetation assemblages during the lake's Late Quaternary paleodepositional history. After the stringent removal of contaminants and sequence artifacts, taxonomic assignment of the remaining genuine trnL-P6 reads showed that native nitrogen-fixing legumes, C3 grasses, and shallow wetland vegetation (Alocasia) were most strongly associated with >1-million-year-old (>1 Ma) peats and silts (114-98.8 m composite depth; mcd), which were deposited in a landscape of active river channels, shallow lakes, and peat-swamps. A statistically significant shift toward partly submerged shoreline vegetation that was likely rooted in anoxic muddy soils (i.e., peatland forest trees and wetland C3 grasses (Oryzaceae) and nutrient-demanding aquatic herbs (presumably Oenanthe javanica)) occurred at 76 mcd (~0.8 Ma), ~0.2 Ma after the transition into a permanent lake. This wetland vegetation was most strongly associated with diatom ooze (46-37 mcd), thought to be deposited during maximum nutrient availability and primary productivity. Herbs (Brassicaceae), trees/shrubs (Fabaceae and Theaceae), and C3 grasses correlated with inorganic parameters, indicating increased drainage of ultramafic sediments and laterite soils from the lakes' catchment, particularly at times of inferred drying. Downcore variability in trnL-P6 from tropical forest trees (Toona), shady ground cover herbs (Zingiberaceae), and tree orchids (Luisia) most strongly correlated with sediments of a predominantly felsic signature considered to be originating from the catchment of the Loeha River draining into Lake Towuti during wetter climate conditions. However, the co-correlation with dry climate-adapted trees (i.e., Castanopsis or Lithocarpus) plus C4 grasses suggests that increased precipitation seasonality also contributed to the increased drainage of felsic Loeha River sediments. This multiproxy approach shows that despite elevated in situ temperatures, tropical lake sediments potentially comprise long-term archives of ancient environmental DNA for reconstructing ecosystems, which warrants further exploration.

Nectin-4 expression in a subset of cutaneous adnexal carcinomas: A potential target for therapy with enfortumab vedotin

BACKGROUND

Enfortumab vedotin (EV) is an antibody-drug conjugate directed against Nectin-4 that is used to treat urothelial carcinoma. Nectin-4 is inherently expressed in the skin and adnexal structures. Since therapeutic options for cutaneous adnexal carcinomas are limited, we sought to evaluate Nectin-4 expression in adnexal carcinomas and benign adnexal neoplasms to identify tumors that are potentially targetable with EV.

METHODS

Eight sebaceous carcinomas (seven periocular and one lymph node metastasis), eight digital papillary adenocarcinomas, seven squamoid eccrine ductal carcinomas, eight poromas, eight trichilemmomas, and seven sebaceous adenomas were subjected to immunohistochemical staining for anti-Nectin-4 antibody. H-scores for Nectin-4 expression were calculated.

RESULTS

Benign adnexal neoplasms had a significantly lower mean (±SD) Nectin-4 H-score (142.6 ± 39.1) than did the adnexal carcinomas (198 ± 90.8; p = 0.006). Nectin-4 was expressed in 91% (21/23) of adnexal carcinomas. Sebaceous carcinomas frequently exhibited high expression of Nectin-4 (88% [7/8]), with a mean (±SD) H-score (258.1 ± 58.4) significantly higher than those for digital papillary adenocarcinomas (197.5 ± 52.5; p = 0.035) and squamoid eccrine ductal carcinomas (131.4 ± 114.1; p = 0.031). Sebaceous carcinomas also had significantly higher H-scores than did sebaceous adenomas (186.4 ± 25.0; p = 0.013).

CONCLUSIONS

Increased Nectin-4 expression in a subset of cutaneous adnexal carcinomas, particularly sebaceous carcinomas, reveals that EV is a potential therapeutic option for these tumors.

Autologous HER2-specific CAR T cells after lymphodepletion for advanced sarcoma: a phase 1 trial

In this prospective, interventional phase 1 study for individuals with advanced sarcoma, we infused autologous HER2-specific chimeric antigen receptor T cells (HER2 CAR T cells) after lymphodepletion with fludarabine (Flu) ± cyclophosphamide (Cy): 1 × 108 T cells per m2 after Flu (cohort A) or Flu/Cy (cohort B) and 1 × 108 CAR+ T cells per m2 after Flu/Cy (cohort C). The primary outcome was assessment of safety of one dose of HER2 CAR T cells after lymphodepletion. Determination of antitumor responses was the secondary outcome. Thirteen individuals were treated in 14 enrollments, and seven received multiple infusions. HER2 CAR T cells expanded after 19 of 21 infusions. Nine of 12 individuals in cohorts A and B developed grade 1-2 cytokine release syndrome. Two individuals in cohort C experienced dose-limiting toxicity with grade 3-4 cytokine release syndrome. Antitumor activity was observed with clinical benefit in 50% of individuals treated. The tumor samples analyzed showed spatial heterogeneity of immune cells and clustering by sarcoma type and by treatment response. Our results affirm HER2 as a CAR T cell target and demonstrate the safety of this therapeutic approach in sarcoma. ClinicalTrials.gov registration: NCT00902044 .

From little things big things grow: enhancement of an acoustic telemetry network to monitor broad-scale movements of marine species along Australia's east coast

BACKGROUND

Acoustic telemetry has become a fundamental tool to monitor the movement of aquatic species. Advances in technology, in particular the development of batteries with lives of > 10 years, have increased our ability to track the long-term movement patterns of many species. However, logistics and financial constraints often dictate the locations and deployment duration of acoustic receivers. Consequently, there is often a compromise between optimal array design and affordability. Such constraints can hinder the ability to track marine animals over large spatial and temporal scales. Continental-scale receiver networks have increased the ability to study large-scale movements, but significant gaps in coverage often remain.

METHODS

Since 2007, the Integrated Marine Observing System's Animal Tracking Facility (IMOS ATF) has maintained permanent receiver installations on the eastern Australian seaboard. In this study, we present the recent enhancement of the IMOS ATF acoustic tracking infrastructure in Queensland to collect data on large-scale movements of marine species in the northeast extent of the national array. Securing a relatively small initial investment for expanding receiver deployment and tagging activities in Queensland served as a catalyst, bringing together a diverse group of stakeholders (research institutes, universities, government departments, port corporations, industries, Indigenous ranger groups and tourism operators) to create an extensive collaborative network that could sustain the extended receiver coverage into the future. To fill gaps between existing installations and maximise the monitoring footprint, the new initiative has an atypical design, deploying many single receivers spread across 2,100 km of Queensland waters.

RESULTS

The approach revealed previously unknown broad-scale movements for some species and highlights that clusters of receivers are not always required to enhance data collection. However, array designs using predominantly single receiver deployments are more vulnerable to data gaps when receivers are lost or fail, and therefore "redundancy" is a critical consideration when designing this type of array.

CONCLUSION

Initial results suggest that our array enhancement, if sustained over many years, will uncover a range of previously unknown movements that will assist in addressing ecological, fisheries, and conservation questions for multiple species.

Mosaic deletion of claudin-5 reveals rapid non-cell-autonomous consequences of blood-brain barrier leakage

Claudin-5 (CLDN5) is an endothelial tight junction protein essential for blood-brain barrier (BBB) formation. Abnormal CLDN5 expression is common in brain disease, and knockdown of Cldn5 at the BBB has been proposed to facilitate drug delivery to the brain. To study the consequences of CLDN5 loss in the mature brain, we induced mosaic endothelial-specific Cldn5 gene ablation in adult mice (Cldn5iECKO). These mice displayed increased BBB permeability to tracers up to 10 kDa in size from 6 days post induction (dpi) and ensuing lethality from 10 dpi. Single-cell RNA sequencing at 11 dpi revealed profound transcriptomic differences in brain endothelial cells regardless of their Cldn5 status in mosaic mice, suggesting major non-cell-autonomous responses. Reactive microglia and astrocytes suggested rapid cellular responses to BBB leakage. Our study demonstrates a critical role for CLDN5 in the adult BBB and provides molecular insight into the consequences and risks associated with CLDN5 inhibition.

A loss of function mutation in CLDN25 causing Pelizaeus-Merzbacher-like leukodystrophy

Claudin-25 (CLDN-25), also known as Claudin containing domain 1, is an uncharacterized claudin family member. It has less conserved amino acid sequences when compared to other claudins. It also has a very broad tissue expression profile and there is currently a lack of functional information from murine knockout models. Here, we report a de novo missense heterozygous variant in CLDN25 (c. 745G>C, p. A249P) found in a patient diagnosed with Pelizaeus-Merzbacher-like leukodystrophy and presenting with symptoms such as delayed motor development, several episodes of tonic absent seizures and generalized dystonia. The variant protein does not localize to the cell-cell borders where it would normally be expected to be expressed. Amino acid position 249 is located 4 amino acids from the C-terminal end of the protein where most claudin family members have a conserved binding motif for the key scaffolding protein ZO-1. However, CLDN-25 does not contain this motif. Here, we show that the C-terminal end of CLDN-25 is required for its junctional localization in a ZO-1 independent manner. The A249P mutant protein as well as a deletion mutant lacking its last 5 C-terminal amino acids also failed to localize to the cell-cell border in vitro. Intriguingly, cellular knockout of CLDN25, in vitro, appeared to increase the integrity of the tight junction between 2 contacting cells, while driving highly unusual increased movement of solutes between cells. We propose that the barrier function of CLDN-25 is akin to a decoy claudin, whereby decreasing its expression in "leaky" epithelial cells and endothelial cells will drive dynamic changes in the adhesion and interaction capacity of cell-cell contact points. While it remains unclear how this de novo CLDN-25 mutant induces leukodystrophy, our findings strongly suggest that this mutation induces haploinsufficiency of CLDN-25. Elucidating the function of this uncharacterized claudin protein will lead to a better understanding of the role of claudin proteins in health and disease.

Treatment with PB125® Increases Femoral Long Bone Strength in 15-Month-Old Female Hartley Guinea Pigs

Nuclear factor-erythroid 2-related factor-2 (Nrf2) is a transcription factor that serves as a master regulator of anti-inflammatory agents, phase I xenobiotic, and phase II antioxidant enzymes, all of which provide a cytoprotective role during disease progression. We hypothesized that oral administration of a purported phytochemical Nrf2-activator, PB125®, would increase long bone strength in aging Hartley guinea pigs, a model prone to musculoskeletal decline. Male (N = 56) and female (N = 56) guinea pigs were randomly assigned to receive daily oral treatment with either PB125® or vehicle control. Animals were treated for a consecutive 3-months (starting at 2-months of age) or 10-months (starting at 5-months of age) and sacrificed at 5-months or 15-months of age, respectively. Outcome measures included: (1) ANY-maze™ enclosure monitoring, (2) quantitative microcomputed tomography, and (3) biomechanical testing. Treatment with PB125® for 10 months resulted in increased long bone strength as determined by ultimate bending stress in female Hartley guinea pigs. In control groups, increasing age resulted in significant effects on geometric and structural properties of long bones, as well as a trending increase in ultimate bending stress. Furthermore, both age and sex had a significant effect on the geometric properties of both cortical and trabecular bone. Collectively, this work suggests that this nutraceutical may serve as a promising target and preventive measure in managing the decline in bone mass and quality documented in aging patients. Auxiliary to this main goal, this work also capitalized upon 5 and 15-month-old male and female animals in the control group to characterize age- and sex-specific differences on long bone geometric, structural, and material properties in this animal model.

Blood-brain barrier disruption and sustained systemic inflammation in individuals with long COVID-associated cognitive impairment

Vascular disruption has been implicated in coronavirus disease 2019 (COVID-19) pathogenesis and may predispose to the neurological sequelae associated with long COVID, yet it is unclear how blood-brain barrier (BBB) function is affected in these conditions. Here we show that BBB disruption is evident during acute infection and in patients with long COVID with cognitive impairment, commonly referred to as brain fog. Using dynamic contrast-enhanced magnetic resonance imaging, we show BBB disruption in patients with long COVID-associated brain fog. Transcriptomic analysis of peripheral blood mononuclear cells revealed dysregulation of the coagulation system and a dampened adaptive immune response in individuals with brain fog. Accordingly, peripheral blood mononuclear cells showed increased adhesion to human brain endothelial cells in vitro, while exposure of brain endothelial cells to serum from patients with long COVID induced expression of inflammatory markers. Together, our data suggest that sustained systemic inflammation and persistent localized BBB dysfunction is a key feature of long COVID-associated brain fog.

Circulating myeloid-derived MMP8 in stress susceptibility and depression

Psychosocial stress has profound effects on the body, including the immune system and the brain1,2. Although a large number of pre-clinical and clinical studies have linked peripheral immune system alterations to stress-related disorders such as major depressive disorder (MDD)3, the underlying mechanisms are not well understood. Here we show that expression of a circulating myeloid cell-specific proteinase, matrix metalloproteinase 8 (MMP8), is increased in the serum of humans with MDD as well as in stress-susceptible mice following chronic social defeat stress (CSDS). In mice, we show that this increase leads to alterations in extracellular space and neurophysiological changes in the nucleus accumbens (NAc), as well as altered social behaviour. Using a combination of mass cytometry and single-cell RNA sequencing, we performed high-dimensional phenotyping of immune cells in circulation and in the brain and demonstrate that peripheral monocytes are strongly affected by stress. In stress-susceptible mice, both circulating monocytes and monocytes that traffic to the brain showed increased Mmp8 expression following chronic social defeat stress. We further demonstrate that circulating MMP8 directly infiltrates the NAc parenchyma and controls the ultrastructure of the extracellular space. Depleting MMP8 prevented stress-induced social avoidance behaviour and alterations in NAc neurophysiology and extracellular space. Collectively, these data establish a mechanism by which peripheral immune factors can affect central nervous system function and behaviour in the context of stress. Targeting specific peripheral immune cell-derived matrix metalloproteinases could constitute novel therapeutic targets for stress-related neuropsychiatric disorders.

Measures of performance and proficiency in robotic assisted surgery: a systematic review

Robotic assisted surgery (RAS) has seen a global rise in adoption. Despite this, there is not a standardised training curricula nor a standardised measure of performance. We performed a systematic review across the surgical specialties in RAS and evaluated tools used to assess surgeons' technical performance. Using the PRISMA 2020 guidelines, Pubmed, Embase and the Cochrane Library were searched systematically for full texts published on or after January 2020-January 2022. Observational studies and RCTs were included; review articles and systematic reviews were excluded. The papers' quality and bias score were assessed using the Newcastle Ottawa Score for the observational studies and Cochrane Risk Tool for the RCTs. The initial search yielded 1189 papers of which 72 fit the eligibility criteria. 27 unique performance metrics were identified. Global assessments were the most common tool of assessment (n = 13); the most used was GEARS (Global Evaluative Assessment of Robotic Skills). 11 metrics (42%) were objective tools of performance. Automated performance metrics (APMs) were the most widely used objective metrics whilst the remaining (n = 15, 58%) were subjective. The results demonstrate variation in tools used to assess technical performance in RAS. A large proportion of the metrics are subjective measures which increases the risk of bias amongst users. A standardised objective metric which measures all domains of technical performance from global to cognitive is required. The metric should be applicable to all RAS procedures and easily implementable. Automated performance metrics (APMs) have demonstrated promise in their wide use of accurate measures.

Incidence and Geographical Distribution of Adrenocortical Carcinoma: Retrospective Analysis of a State Cancer Registry

OBJECTIVE

Adrenocortical carcinoma (ACC) is a rare malignancy without established association with environmental risk factors. ACC incidence is stable based on large surgical databases while referral centers data reported increasing number of cases seen. We studied ACC incidence and distribution at a county level to find potential ACC "hot spots" that could be linked to environmental exposures.

METHODS

A retrospective analysis of Texas Cancer Registry that included ACC patients diagnosed between 2000 and 2018. County-level heatmaps were created and compared with breast, prostate, and lung cancer.

RESULTS

We identified 448 ACC cases during the study period. Cases were registered in 110 of the 254 counties (43.3%) in Texas, representing 92.74% of the total population. The median incidence was 23 new cases/y (range 14-33). The mean population-adjusted ACC incidence rate was 0.104 per 100 000 per year (standard deviation 0.005; 95% CI, 0.092-0.116). Seven counties (6.3%) accounted for 215 (48.0%) cases, with more than 10 cases each and median standardized incidence ratio (SIR) of 0.1 (range, 0.0-0.9). One hundred three counties (93.7%) accounted for the remaining 233 cases (52%), with fewer than 10 cases per county. The highest standardized incidence ratios were found in counties with a median population of fewer than 14 000 residents and with only one reported case.

CONCLUSION

Our analysis is the first report to create ACC heatmap and could not detect any geographic clustering of ACC in Texas. The incidence of ACC remained stable and consistent with data from other large databases.

Analysis of Barbiturates in Urine by LC-MS/MS

In the method described here, an aliquot of a urine sample is analyzed to detect barbiturates through dilution and ultra-high-performance chromatography-tandem mass spectrometry (UPLC-MS/MS) using deuterated internal standards. This assay detects the presence of nine barbiturate drugs-amobarbital, barbital, butalbital, butabarbital, mephobarbital, secobarbital, pentobarbital, phenobarbital, and thiopental. This protocol describes two LC separation methods-first LC method (2.2 min/sample) is intended to be used as a first step of the analysis that does not separate amobarbital and pentobarbital, and a second, longer (2.7 min/sample) LC method is intended to be used only for samples which have a peak in the amobarbital/pentobarbital retention time on the shorter LC method. Since the frequency at which amobarbital and pentobarbital are observed in clinical populations is low, the shorter LC method helps gain efficiency in a high-volume laboratory environment. Additional features of this protocol that help in efficiency gain are automated extraction using Hamilton™ liquid handling system and algorithmic data review using Ascent™ software.

Bilateral pulmonary artery banding in higher risk neonates with hypoplastic left heart syndrome

Objectives

Limited data on performing bilateral pulmonary artery banding (BPAB) before stage 1 Norwood procedure suggest that some patients may benefit through the postponement of the major cardiopulmonary bypass procedure. The objective of this study was to evaluate the effectiveness of BPAB in the surgical management of high-risk patients with hypoplastic left heart syndrome (HLHS).

Methods

A retrospective review of all high-risk neonates with HLHS who underwent BPAB at our institution was performed. No patients, including those with intact or highly restrictive atrial septum (IAS), were excluded.

Results

Between October 2015 and April 2021, 49 neonates with HLHS (including 6 with IAS) underwent BPAB, 40 of whom progressed to the Norwood procedure. Risk factors for not progressing to the Norwood procedure after BPAP include low birth weight (P = .043), the presence of multiple extracardiac anomalies (P = .005), and the presence of genetic disorders (P = .028). Operative mortality was 7.5% (3/40). IAS was associated with operative mortality (P = .022).

Conclusions

The strategy of BPAB prestage 1 Norwood procedure was successful in identifying at-risk patients and improving Norwood survival. Although not all patients will need this hybrid approach, a significant number can be expected to benefit from this tactic. These results support the need for a substantial hybrid strategy, in addition to a primary stage 1 Norwood surgical strategy, in the management of HLHS.

Polypathology-associated neurodegeneration after remote head injury

Traumatic brain injury (TBI) is a leading cause of morbidity and mortality worldwide. TBI ranges from mild to severe and is a recognized risk factor for later neurodegenerative conditions including chronic traumatic encephalopathy (CTE), Alzheimer disease (AD) and Parkinson disease (PD). The development of CTE is typically associated with repetitive exposure to mild TBI (mTBI), while a single moderate-to-severe TBI is considered a risk factor for AD and PD. Polypathology is common, and the lines between these conditions post TBI can be somewhat blurred. The mechanisms through which TBI leads to future neurodegeneration are not well understood. Heterogeneity and distance from the injury or injuries and individual genetic and environmental factors make clinical studies difficult. We present the case of an 82-year-old man who died 4 years after developing a phenotypically mixed dementia with neuropsychiatric features and parkinsonism. He had a remote history of a severe TBI 40 years prior, following a road traffic accident which caused a large right frontal injury, requiring neurosurgical intervention. Post-mortem neuropathological examination demonstrated abnormal phosphorylated-Tau (p-Tau), beta-amyloid plaques (Aβ) and α-synuclein deposition. Spatial immunohistochemical analysis demonstrated increased perivascular accumulation of p-Tau with blood-brain barrier (BBB) disruption at the site of injury, which decreased with distance from the injury site. The appearances are suggestive of initial vascular disruption with persisting BBB disruption as a driver of the pathology.

EV-301 long-term outcomes: 24-month findings from the phase III trial of enfortumab vedotin versus chemotherapy in patients with previously treated advanced urothelial carcinoma

INTRODUCTION

This exploratory analysis evaluated efficacy and safety data for enfortumab vedotin versus chemotherapy over a median follow-up of ∼2 years from EV-301.

MATERIALS AND METHODS

Patients with locally advanced/metastatic urothelial carcinoma with prior platinum-containing chemotherapy and disease progression during/after programmed cell death protein 1/ligand 1 inhibitor treatment were randomized to enfortumab vedotin or chemotherapy (docetaxel, paclitaxel, vinflunine). Endpoints were overall survival (primary), progression-free survival (PFS), objective response, and safety.

RESULTS

In total, 608 patients were included (enfortumab vedotin, n = 301; chemotherapy, n = 307). With a median follow-up of 23.75 months, 444 deaths had occurred (enfortumab vedotin, n = 207; chemotherapy, n = 237). Risk of death was reduced by 30% with enfortumab vedotin versus chemotherapy [hazard ratio (HR) 0.70 (95% confidence interval [CI] 0.58-0.85); one-sided, log-rank P = 0.00015]; PFS improved with enfortumab vedotin [HR 0.63 (95% CI 0.53-0.76); one-sided, log-rank P < 0.00001]. Treatment-related adverse event rates were 93.9% for enfortumab vedotin and 91.8% for chemotherapy; grade ≥ 3 event rates were 52.4% and 50.5%, respectively. Grade ≥ 3 treatment-related decreased neutrophil count (14.1% versus 6.1%), decreased white blood cell count (7.2% versus 1.4%), and anemia (7.9% versus 2.7%) were more common with chemotherapy versus enfortumab vedotin; maculopapular rash (7.4% versus 0%), fatigue (6.8% versus 4.5%), and peripheral sensory neuropathy (5.1% versus 2.1%) were more common with enfortumab vedotin. Of special interest adverse events, treatment-related skin reactions occurred in 47.3% of patients receiving enfortumab vedotin and 15.8% of patients receiving chemotherapy; peripheral neuropathy occurred in 48.0% versus 31.6%, respectively, and hyperglycemia in 6.8% versus 0.3%.

CONCLUSIONS

After a median follow-up of ∼2 years, enfortumab vedotin maintained clinically meaningful overall survival benefit versus chemotherapy, consistent with findings from the EV-301 primary analysis; PFS and overall response benefit remained consistent. Adverse events were manageable; no new safety signals were observed.

Evaluation of Inflammation in the Peripheral Multiple Sclerosis Retina Using Ultra-Widefield Optical Coherence Tomography: A Pilot Study

BACKGROUND AND OBJECTIVE

Reports of fundus fluorescein angiography (FFA) in active multiple sclerosis (MS) have shown peripheral perivenous sheathing. We sought to assess the feasibility of ultra-widefield (UWF) FFA and optical coherence tomography (OCT) in assessing the peripheral retina in MS.

MATERIALS AND METHODS

Participants with MS and healthy controls underwent bilateral UWF fundus photography and FFA. Swept-source OCTs were captured centrally, peripherally, and to delineate any abnormalities visualized.

RESULTS

We recruited five people with relapsing remitting MS, with a mean age of 36.9 (± 9.9), mean disease duration of 11 years (± 6.3), and a median expanded disability status score of 0.75 (0 to 2.5). In all MS participants, the disease was not active clinically or radiologically. Using UWF-FFA and OCT, we did not detect clear evidence of peripheral retinal abnormalities, which is consistent with the participants having inactive MS.

CONCLUSION

A pilot study using UWF-FFA and peripheral OCT to examine the retina in MS suggests that it may be useful to perform a larger prospective longitudinal study to establish its potential as a monitor of disease activity. [Ophthalmic Surg Lasers Imaging Retina 2023;54:586-588.].

Assessing Displacement of Plastic Interstitial Catheters in Image-Guided Gynecological HDR Brachytherapy

PURPOSE/OBJECTIVE(S)

Interstitial HDR brachytherapy involves precise, localized delivery to targets with high dose gradients, sparing adjacent organs at risk. Due to the proximity of the rectum and bladder to the target, deviations in the catheters with respect to patient anatomy can change dose to those structures. While utilizing plastic interstitial catheters allows the patient to receive hyperthermia therapy during their course of interstitial treatment, the plastic catheters were observed to show significant deflection when the metal stylets are removed for treatment. The hyperthermia electrodes and the HDR source cable are both wires of approximately the same thickness. The purpose of this study is to assess the magnitude and deflection of the plastic catheters for gynecologic interstitial plans and determine whether using flexible wires for visualization on pre-treatment imaging is suitable for reconstructing the actual treatment received.

MATERIALS/METHODS

Pre-treatment CT images where the stylets were utilized for catheter visualization were registered to a subsequent CT scan with the metal stylets removed. The original treatment dwell positions were adjusted to the second CT to evaluate 3D catheter displacement and dose distributions calculated for the bladder, rectum, and target. The plans were subsequently reconstructed on a pre-planning CT with flexible 20-gauge wires instead of metal stylets to determine their suitability as a surrogate for stylets.

RESULTS

Absolute 3D displacement for all patients was 3.5 ± 5.4 mm (n = 3433 catheter dwell positions, mean ± SD, p < 0.001) comparing plans with the stylet in versus out. Absolute catheter deflection for interstitial treatments increased with the removal of the metal stylets with a difference of 0.75 ± 0.49° (n = 313 catheters, mean ± SD, p < 0.01). The plans utilizing flexible wire instead of stylets are observed to correlate with the plans with no stylets with absolute 3D displacement and angular deflection of 1.1 ± 0.6 mm and 0.35° ± 0.3° respectively (n = 39 catheters, mean ± SD, p > 0.2). While the average target EQD2 D90 reduced by 5% ± 5% by planning without the stylets, four patients would have experienced a deviation from the prescription by >10%. There was an overall decrease in bladder D2cc and overall increase in rectal D2cc in the plans with the stylets utilized vs removed. Bladder D2cc, rectal D2cc, and target coverage showed no appreciable difference between utilizing flexible wires and the plans without. The difference in HU between the metal stylets and flexible wires was negligible.

CONCLUSION

Catheter reconstruction in interstitial gynecological treatments with CT imaging revealed significant changes in catheter positioning with respect to the target volume once the stylets are removed for treatment. Using flexible wires of similar thickness to the source cable allow for more accurate tracking during planning without distorting the patient's anatomy or the treatment images, preserving the integrity of the treatment plan.

Microbially mediated fossil concretions and their characterization by the latest methodologies: a review

The study of well-preserved organic matter (OM) within mineral concretions has provided key insights into depositional and environmental conditions in deep time. Concretions of varied compositions, including carbonate, phosphate, and iron-based minerals, have been found to host exceptionally preserved fossils. Organic geochemical characterization of concretion-encapsulated OM promises valuable new information of fossil preservation, paleoenvironments, and even direct taxonomic information to further illuminate the evolutionary dynamics of our planet and its biota. Full exploitation of this largely untapped geochemical archive, however, requires a sophisticated understanding of the prevalence, formation controls and OM sequestration properties of mineral concretions. Past research has led to the proposal of different models of concretion formation and OM preservation. Nevertheless, the formation mechanisms and controls on OM preservation in concretions remain poorly understood. Here we provide a detailed review of the main types of concretions and formation pathways with a focus on the role of microbes and their metabolic activities. In addition, we provide a comprehensive account of organic geochemical, and complimentary inorganic geochemical, morphological, microbial and paleontological, analytical methods, including recent advancements, relevant to the characterization of concretions and sequestered OM. The application and outcome of several early organic geochemical studies of concretion-impregnated OM are included to demonstrate how this underexploited geo-biological record can provide new insights into the Earth's evolutionary record. This paper also attempts to shed light on the current status of this research and major challenges that lie ahead in the further application of geo-paleo-microbial and organic geochemical research of concretions and their host fossils. Recent efforts to bridge the knowledge and communication gaps in this multidisciplinary research area are also discussed, with particular emphasis on research with significance for interpreting the molecular record in extraordinarily preserved fossils.

A novel mitochondrial complex I ROS inhibitor partially improves muscle regeneration in adult but not old mice

It is unclear whether mitochondrial dysfunction and redox stress contribute to impaired age-related muscle regenerative capacity. Here we characterized a novel compound, BI4500, that inhibits the release of reactive oxygen species (ROS) from the quinone site in mitochondrial complex I (site IQ). We tested the hypothesis that ROS release from site IQ contributes to impaired regenerative capacity in aging muscle. Electron transfer system site-specific ROS production was measured in adult and aged mouse isolated muscle mitochondria and permeabilized gastrocnemius fibers. BI4500 inhibited ROS production from site IQ in a concentration-dependent manner (IC50 = ∼985 nM) by inhibiting ROS release without impairing complex I-linked respiration. In vivo BI4500 treatment decreased ROS production from site IQ. Muscle injury and sham injury were induced using barium chloride or vehicle injection to the tibialis anterior (TA) muscle in adult and aged male mice. On the same day as injury, mice began a daily gavage of 30 mg/kg BI4500 (BI) or placebo (PLA). Muscle regeneration (H&E, Sirius Red, Pax7) was measured at 5 and 35 days after injury. Muscle injury increased centrally nucleated fibers (CNFs) and fibrosis with no treatment or age effect. There was a significant age by treatment interaction for CNFs at 5- and 35-days post injury with significantly more CNFs in BI adults compared to PLA adults. Muscle fiber cross-sectional area (CSA) recovered significantly more in adult BI mice (-89 ± 365 μm2) compared to old PLA (-599 ± 153 μm2) and old BI (-535 ± 222 μm2, mean ± SD). In situ TA force recovery was measured 35 days after injury and was not significantly different by age or treatment. Inhibition of site IQ ROS partially improves muscle regeneration in adult but not old muscle demonstrating a role for CI ROS in the response to muscle injury. Site IQ ROS does not contribute to impaired regenerative capacity in aging.

Patterns of endocardial fibroelastosis without atrioventricular block in fetuses exposed to anti-Ro/SSA antibodies

Anti-Ro/SSA-antibody-mediated endocardial fibroelastosis (EFE) without atrioventricular (AV) block at presentation is a rare cardiac phenotype. We report on 11 fetuses with this rare type of anti-Ro/SSA-antibody-mediated cardiac involvement, presenting with a distinctive echocardiographic pattern of EFE. Eleven fetuses with isolated EFE at presentation were included from four cardiac centers, and experienced fetal cardiologists reached a consensus regarding EFE location on echocardiography at presentation. Interval changes to subsequent fetal and postnatal echocardiograms were assessed to evaluate response to therapy. Echocardiographic markers of cardiac performance, including diastolic function and AV conduction, were reviewed. Ten fetuses were found to have EFE of the aortic root, proximal aorta and/or left ventricular outflow tract. In the same 10 cases, EFE of the pulmonary root, pulmonary artery and/or right ventricular outflow tract was identified. Six cases had atrial EFE and six had EFE of the crux. Four cases were known to be positive for anti-Ro/SSA antibodies prior to diagnosis, whereas, in the remaining seven, echocardiographic findings prompted testing, which was positive in all cases. The AV interval at presentation was normal in all cases, but one fetus subsequently developed AV block. Nine patients were treated with transplacental dexamethasone, five of which also received intravenous immunoglobulin (IVIG), and one received IVIG only. Of the 10 treated cases, six had improvement in EFE as shown by serial imaging and, in four cases, the severity was unchanged. All patients were liveborn. In our cohort, EFE of the aortic and pulmonary arteries and outflow tracts was nearly universal, and involvement of the atria and the crux of the heart was also common. The high survival rate and low burden of AV block are also suggestive of a distinct phenotype of anti-Ro/SSA-antibody-mediated cardiac disease with a favorable prognosis. © 2023 International Society of Ultrasound in Obstetrics and Gynecology.

MicroRNAs in tear fluids predict underlying molecular changes associated with Alzheimer's disease

Extracellular circulating microRNAs (miRNAs) have been discussed as potential biomarkers for Alzheimer's disease (AD) diagnosis. As the retina is a part of the CNS, we hypothesize that miRNAs expression levels in the brain, particularly neocortex-hippocampus, eye tissues, and tear fluids are similar at different stages of AD progression. Ten miRNA candidates were systematically investigated in transgenic APP-PS1 mice, noncarrier siblings, and C57BL/6J wild-type controls at young and old ages. Relative expression levels of tested miRNAs revealed a similar pattern in both APP-PS1 mice and noncarrier siblings when compared with age- and sex-matched wild-type controls. However, the differences seen in expression levels between APP-PS1 mice and noncarrier siblings could possibly have resulted from underlying molecular etiology of AD. Importantly, miRNAs associated with amyloid beta (Aβ) production (-101a, -15a, and -342) and proinflammation (-125b, -146a, and -34a) showed significant up-regulations in the tear fluids with disease progression, as tracked by cortical Aβ load and reactive astrogliosis. Overall, for the first time, the translational potential of up-regulated tear fluid miRNAs associated with AD pathogenesis was comprehensively demonstrated.

Near-Complete Drusen Resolution With Brolucizumab: A Mechanism for Proinflammatory Mediated Drusen Clearance?

A 68-year-old woman with macular drusen was diagnosed with neovascular age-related macular degeneration (AMD) and treated with intravitreal brolucizumab. She had a good response to treatment with reduced height of the pigment epithelial detachment, and a good visual outcome. Remarkably, she had a near-complete resolution of macular drusen, yet this was accompanied by the development of anterior uveitis. We propose a proinflammatory-based mechanism for the brolucizumab-induced drusen resorption. Identifying the biochemical pathways responsible could hold the potential to discover novel forms of therapy for the treatment of AMD. [Ophthalmic Surg Lasers Imaging Retina 2023;54:371-374.].

Magnesium Deficiency and Cardiometabolic Disease

Magnesium (Mg²⁺) has many physiological functions within the body. These include important roles in maintaining cardiovascular functioning, where it contributes to the regulation of cardiac excitation-contraction coupling, endothelial functioning and haemostasis. The haemostatic roles of Mg²⁺ impact upon both the protein and cellular arms of coagulation. In this review, we examine how Mg²⁺ homeostasis is maintained within the body and highlight the various molecular roles attributed to Mg²⁺ in the cardiovascular system. In addition, we describe how nutritional and/or disease-associated magnesium deficiency, seen in some metabolic conditions, has the potential to influence cardiac and vascular outcomes. Finally, we also examine the potential for magnesium supplements to be employed in the prevention and treatment of cardiovascular disorders and in the management of cardiometabolic health.

Matrix metalloproteinase-3 (MMP-3)-mediated gene therapy for glaucoma

Approximately 80 million people globally are affected by glaucoma, with a projected increase to over 110 million by 2040. Substantial issues surrounding patient compliance remain with topical eye drops, and up to 10% of patients become treatment resistant, putting them at risk of permanent vision loss. The major risk factor for glaucoma is elevated intraocular pressure, which is regulated by the balance between the secretion of aqueous humor and the resistance to its flow across the conventional outflow pathway. Here, we show that adeno-associated virus 9 (AAV9)-mediated expression of matrix metalloproteinase-3 (MMP-3) can increase outflow in two murine models of glaucoma and in nonhuman primates. We show that long-term AAV9 transduction of the corneal endothelium in the nonhuman primate is safe and well tolerated. Last, MMP-3 increases outflow in donor human eyes. Collectively, our data suggest that glaucoma can be readily treated with gene therapy-based methods, paving the way for deployment in clinical trials.

Neurovascular adaptations modulating cognition, mood, and stress responses

The neurovascular unit (NVU) is a dynamic center for substance exchange between the blood and the brain, making it an essential gatekeeper for central nervous system (CNS) homeostasis. Recent evidence supports a role for the NVU in modulating brain function and cognition. In addition, alterations in NVU processes are observed in response to stress, although the mechanisms via which they can affect mood and cognitive functions remain elusive. Here, we summarize recent studies of neurovascular regulation of emotional processes and cognitive function, including under stressful conditions. We also highlight relevant RNA-sequencing (RNA-seq) databases aiming to profile the NVU along with innovative tools to study and manipulate NVU function that can be exploited in the context of cognition and stress research throughout development, aging, or brain disorders.

The CLDN5 gene at the blood-brain barrier in health and disease

The CLDN5 gene encodes claudin-5 (CLDN-5) that is expressed in endothelial cells and forms tight junctions which limit the passive diffusions of ions and solutes. The blood-brain barrier (BBB), composed of brain microvascular endothelial cells and associated pericytes and end-feet of astrocytes, is a physical and biological barrier to maintain the brain microenvironment. The expression of CLDN-5 is tightly regulated in the BBB by other junctional proteins in endothelial cells and by supports from pericytes and astrocytes. The most recent literature clearly shows a compromised BBB with a decline in CLDN-5 expression increasing the risks of developing neuropsychiatric disorders, epilepsy, brain calcification and dementia. The purpose of this review is to summarize the known diseases associated with CLDN-5 expression and function. In the first part of this review, we highlight the recent understanding of how other junctional proteins as well as pericytes and astrocytes maintain CLDN-5 expression in brain endothelial cells. We detail some drugs that can enhance these supports and are being developed or currently in use to treat diseases associated with CLDN-5 decline. We then summarise mutagenesis-based studies which have facilitated a better understanding of the physiological role of the CLDN-5 protein at the BBB and have demonstrated the functional consequences of a recently identified pathogenic CLDN-5 missense mutation from patients with alternating hemiplegia of childhood. This mutation is the first gain-of-function mutation identified in the CLDN gene family with all others representing loss-of-function mutations resulting in mis-localization of CLDN protein and/or attenuated barrier function. Finally, we summarize recent reports about the dosage-dependent effect of CLDN-5 expression on the development of neurological diseases in mice and discuss what cellular supports for CLDN-5 regulation are compromised in the BBB in human diseases.

Ergothioneine, a dietary antioxidant improves amyloid beta clearance in the neuroretina of a mouse model of Alzheimer’s disease

Introduction

Ergothioneine (Ergo) is a naturally occurring dietary antioxidant. Ergo uptake is dependent on the transporter, organic cation transporter novel-type 1 (OCTN1) distribution. OCTN1 is highly expressed in blood cells (myeloid lineage cells), brain and ocular tissues that are likely predisposed to oxidative stress. Ergo may protect the brain and eye against oxidative damage and inflammation, however, the underlying mechanism remains unclear. Amyloid beta (Aβ) clearance is a complex process mediated by various systems and cell types including vascular transport across the blood–brain barrier, glymphatic drainage, and engulfment and degradation by resident microglia and infiltrating innate immune cells. Impaired Aβ clearance is a major cause for Alzheimer’s disease (AD). Here we investigated neuroretinas to explore the neuroprotective effect of Ergo in a transgenic AD mouse model.

Methods

Age-matched groups of Ergo-treated 5XFAD, non-treated 5XFAD, and C57BL/6J wildtype (WT controls) were used to assess Ergo transporter OCTN1 expression and Aβ load along with microglia/macrophage (IBA1) and astrocyte (GFAP) markers in wholemount neuroretinas (n = 26) and eye cross-sections (n = 18). Immunoreactivity was quantified by fluorescence or by semi-quantitative assessments.

Results and discussion

OCTN1 immunoreactivity was significantly low in the eye cross-sections of Ergo-treated and non-treated 5XFAD vs. WT controls. Strong Aβ labeling, detected in the superficial layers in the wholemounts of Ergo-treated 5XFAD vs. non-treated 5XFAD reflects the existence of an effective Aβ clearance system. This was supported by imaging of cross-sections where Aβ immunoreactivity was significantly low in the neuroretina of Ergo-treated 5XFAD vs. non-treated 5XFAD. Moreover, semi-quantitative analysis in wholemounts identified a significantly reduced number of large Aβ deposits or plaques, and a significantly increased number of IBA1(+)ve blood-derived phagocytic macrophages in Ergo-treated 5XFAD vs. non-treated 5XFAD. In sum, enhanced Aβ clearance in Ergo-treated 5XFAD suggests that Ergo uptake may promote Aβ clearance possibly by blood-derived phagocytic macrophages and via perivascular drainage.

The blood-retina barrier in health and disease

The blood-retina barrier (BRB) is the term used to define the properties of the retinal capillaries and the retinal pigment epithelium (RPE), which separate the systemic circulation from the retina. More specifically, the inner blood-retina barrier (iBRB) is used to describe the properties of the endothelial cells that line the microvasculature of the inner retina, while the outer blood-retina barrier (oBRB) refers to the properties of the RPE cells that separate the fenestrated choriocapillaris from the retina. The BRB is not a fixed structure; rather, it is dynamic, with its components making unique contributions to its function and structural integrity, and therefore the retina. For example, while tight junction (TJ) proteins between retinal endothelial cells are the key molecular structures in the maintenance of the iBRB, other cell types surrounding endothelial cells are also important. In fact, this overall structure is termed the neurovascular unit (NVU). The integrity of the BRB is crucial in the maintenance of a 'dry', tightly regulated retinal microenvironment through the regulation of transcellular and paracellular transport. Specifically, breakdown of TJs can result in oedema formation, a hallmark feature of many retinal diseases. Here, we will describe the oBRB briefly, with a more in-depth focus on the structure and function of the iBRB in health and diseased states. Finally, the contribution of the BRB to the pathophysiology of age-related macular degeneration (AMD), diabetic retinopathy (DR) and other rarer retinal diseases will be discussed.

Non-canonical inflammasome activation mediates the adjuvanticity of nanoparticles

The non-canonical inflammasome sensor caspase-11 and gasdermin D (GSDMD) drive inflammation and pyroptosis, a type of immunogenic cell death that favors cell-mediated immunity (CMI) in cancer, infection, and autoimmunity. Here we show that caspase-11 and GSDMD are required for CD8⁺ and Th1 responses induced by nanoparticulate vaccine adjuvants. We demonstrate that nanoparticle-induced reactive oxygen species (ROS) are size dependent and essential for CMI, and we identify 50- to 60-nm nanoparticles as optimal inducers of ROS, GSDMD activation, and Th1 and CD8⁺ responses. We reveal a division of labor for IL-1 and IL-18, where IL-1 supports Th1 and IL-18 promotes CD8⁺ responses. Exploiting size as a key attribute, we demonstrate that biodegradable poly-lactic co-glycolic acid nanoparticles are potent CMI-inducing adjuvants. Our work implicates ROS and the non-canonical inflammasome in the mode of action of polymeric nanoparticulate adjuvants and establishes adjuvant size as a key design principle for vaccines against cancer and intracellular pathogens.

1336 TOWARDS AN UNDERSTANDING OF THE BIOLOGICAL MECHANISMS OF DELIRIUM USING FUNCTIONAL MRI: PILOT STUDY

Introduction

Delirium is a common condition in older hospitalised patients causing high morbidity and mortality. The neurobiological basis for delirium is uncertain and, for numerous reasons, research in this area has been limited. Several recent studies have demonstrated that functional neuroimaging in delirium is achievable and has suggested that a brain region termed the default mode network (DMN), may play a cardinal role in delirium pathogenesis. We set out to develop a pilot study to demonstrate that it is feasible to undertake functional magnetic resonance imaging (fMRI) scans in older patients with acute delirium.

Methods

Observational pilot study obtaining a fMRI scan of inpatients in an Australian, tertiary hospital, geriatric ward. Eligible patients diagnosed as delirious by a geriatrician were compared against non-delirious controls. Informed consent was obtained. A novel scanning paradigm was developed. Sequences assed brain structure and functional networks in resting state and during a simple task of sustained attention and response inhibition.

Results

11 participants have been scanned. 6 participants were delirious: mean age 81 years (range 77 – 85 years), 3 female. 5 participants were non-delirious: mean age 83.4years (range 79 -90 years), 2 female. 10 of the 11 participants completed the full imaging protocol, including task engagement. Head movement during scanning, was generally within acceptable limits. Data demonstrates considerable cortical atrophy and ventricular enlargement consistent with age. Preliminary fMRI analyses show a variable pattern of cortical recruitment during task engagement in delirious patients.

Conclusions

These findings show it is ethically and logistically feasible to engage elderly patients with acute delirium into a high end structural and functional imaging study.

Overcoming variant mutation-related impacts on viral sequencing and detection methodologies

Prompt and accurate pathogen identification, by diagnostics and sequencing, is an effective tool for tracking and potentially curbing pathogen spread. Targeted detection and amplification of viral genomes depends on annealing complementary oligonucleotides to genomic DNA or cDNA. However, genomic mutations that occur during viral evolution may perturb annealing, which can result in incomplete sequence coverage of the genome and/or false negative diagnostic test results. Herein, we demonstrate how to assess, test, and optimize sequencing and detection methodologies to attenuate the negative impact of mutations on genome targeting efficiency. This evaluation was conducted using in vitro-transcribed (IVT) RNA as well as RNA extracted from clinical SARS-CoV-2 variant samples, including the heavily mutated Omicron variant. Using SARS-CoV-2 as a current example, these results demonstrate how to maintain reliable targeted pathogen sequencing and how to evaluate detection methodologies as new variants emerge.

Predictive capacity of a miRNA panel in identifying teratoma in post-chemotherapy consolidation surgeries

Objectives

To investigate the utility of a novel serum miRNA biomarker panel to distinguish teratoma from nonmalignant necrotic/fibrotic tissues or nonviable tumours in patients with NSGCT undergoing post-chemotherapy consolidation surgery.

Patients and methods

We prospectively collected pre-surgical serum samples from 22 consecutive testicular NSGCT patients with residual NSGCT after chemotherapy undergoing post-chemotherapy consolidation surgery. We measured serum miRNA expression of four microRNAs (miRNA-375, miRNA-200a-3p, miRNA-200a-5p and miRNA-200b-3p) and compared with pathologic findings at time of surgery. Receiver operating characteristic (ROC) curves were performed to assess the ability of these miRNA to differentiate between teratoma and necrosis or viable malignancy.

Results

Twenty-two patients with NSGCT were split into two groups based on pathology at time of post-chemotherapy consolidation surgery (teratoma group vs. necrosis/fibrosis/viable tumour group, i.e., NFVT). Patients with teratoma were older at diagnosis compared with those patients with NFVT (median age 28.7 vs. 23.9). Patients with NFVT were more likely to have embryonal carcinoma in their primary tumour (81.8% vs. 27.3%; p = 0.01). The majority of patients in both groups were stage III (63.6% vs. 72.7%). In this analysis, none of the miRNAs had good sensitivity or specificity to predict teratoma. There was no significant association between the expression levels of the miRNAs and the presence of teratoma. There was no statistically significant correlation between any of the miRNAs and teratoma size.

Conclusion

This novel miRNA panel (miRNA-375, miRNA-200a-3p, miRNA-200a-5p and miRNA-200b-3p) did not distinguish teratoma from nonmalignant necrotic/fibrotic tissues or nonviable tumours in patients with NSGCT undergoing post-chemotherapy consolidation surgery.

Recurrent de novo mutations in CLDN5 induce an anion-selective blood-brain barrier and alternating hemiplegia

Claudin-5 is the most enriched tight junction protein at the blood–brain barrier. Perturbations in its levels of expression have been observed across numerous neurological and neuropsychiatric conditions; however, pathogenic variants in the coding sequence of the gene have never been reported previously. Here, we report the identification of a novel de novo mutation (c.178G>A) in the CLDN5 gene in two unrelated cases of alternating hemiplegia with microcephaly. This mutation (G60R) lies within the first extracellular loop of claudin-5 and based on protein modelling and sequence alignment, we predicted it would modify claudin-5 to become an anion-selective junctional component as opposed to a purely barrier-forming protein.

Generation of stably transfected cell lines expressing wild-type or G60R claudin-5 showed that the tight junctions could still form in the presence of the G60R mutation but that the barrier against small molecules was clearly attenuated and displayed higher Cl⁻ ion permeability and lower Na⁺ permeability.

While this study strongly suggests that CLDN5 associated alternating hemiplegia is a channelopathy, it is also the first study to identify the conversion of the blood–brain barrier to an anion-selective channel mediated by a dominant acting variant in CLDN5.

POS1510-HPR IDENTIFYING THEORY-DRIVEN THERAPEUTIC CONTENT FOR A SMARTPHONE APP FOR THE SELF-MANAGEMENT OF SJOGREN’S SYNDROME

Background

Technology-supported self-management of long-term conditions (e.g., through the use of smartphone apps) provides easily accessible support. However, currently there are no systematically developed, evidence-based smartphone apps for Sjogren’s Syndrome. We took an agile approach to developing such an app: instead of starting “from scratch” we deemed it more efficient and scientifically sound to digitalise relevant components from existing, evidence-based interventions for the symptoms of SS.

Objectives

The present study was desk research, which aimed to deconstruct interventions and resources down to units of theory-driven therapeutic content, to then select from, for the inclusion in an app for the self-management of SS.

Methods

We used deductive and inductive content analysis, to identify behaviour change techniques (BCTs)[1] and behaviour change methods (BCMs)[2]. The materials consisted of published fatigue, pain and sleep interventions (e.g. [3] and [4]), as well as private-facing clinician notes and public facing resources on self-management from Versus Arthritis and the UK NHS’s CRESTA fatigue clinic.

Results

We found 38 active ingredients from the BCT Taxonomy and the BCM intervention mapping approach frameworks, of which at least 14 were overlapping in function. Importantly we noted that BCTs and BCMs were formulated in various ways pertaining to how the interventions should be delivered (form of delivery-FoD) [5]. Further qualitative analysis revealed 6 themes relating to FoD. The theme Interactivity involved presenting information in ways that would involve the reader in actively responding to it in various ways. The theme Reflection was about engaging the recipient in in-depth consideration of their own experience with symptoms and self-management processes. The theme Validation encompassed all the ways in which the illness and management experience was socialised and normalised to remove stigma and sense of isolation. The theme Treatment Rationale was about providing an a-priory transparent, sound, and compelling justification for the self-management actions required from recipients. The theme Discourse pertained to how information was being communicated, e.g., with language that is warm, simple, assertive, etc. Finally, the theme Approaches was about the therapeutic origins of the active ingredients, e.g. Second and Third Wave CBT. These themes indicate that meaningful therapeutic content is missing from commonly used theoretical frameworks for the development of interventions.

Conclusion

Our findings indicate that meaningful therapeutic content is missing from commonly used theoretical frameworks for the development of interventions.

Interventions should not just include BCTs and methods, but also active ingredients pertaining to how these techniques and methods are delivered, i.e., active ingredients relating to FoD. Reflection deserves particular attention in self-management, as it is unclear empirically in apps what is the most effective way to produce the most useful psychological and behavioural insight, and for whom. FoD is a component of intervention development that requires systematising and the present findings can contribute to such efforts.

References

[1]S. Michie, et al. Annals of Behav Med 2013. 46:1

[2]G. Kok, et al. Health Psych Rev 2016. 10:3

[3]S. Hewlett, et al. Ann. Rheum. Dis 2019. 78: 4.

[4]S. D. Kyle, et al. Sleep Med Rev 2015. 23.

[5]S. U. Dombrowski, et al. Brit. J Health Psych 2016. 21: 4

Acknowledgements

I have no acknowledgments to declare.

Disclosure of Interests

None declared

Dysregulation of macrophage PEPD in obesity determines adipose tissue fibro-inflammation and insulin resistance

Resulting from impaired collagen turnover, fibrosis is a hallmark of adipose tissue (AT) dysfunction and obesity-associated insulin resistance (IR). Prolidase, also known as peptidase D (PEPD), plays a vital role in collagen turnover by degrading proline-containing dipeptides but its specific functional relevance in AT is unknown. Here we show that in human and mouse obesity, PEPD expression and activity decrease in AT, and PEPD is released into the systemic circulation, which promotes fibrosis and AT IR. Loss of the enzymatic function of PEPD by genetic ablation or pharmacological inhibition causes AT fibrosis in mice. In addition to its intracellular enzymatic role, secreted extracellular PEPD protein enhances macrophage and adipocyte fibro-inflammatory responses via EGFR signalling, thereby promoting AT fibrosis and IR. We further show that decreased prolidase activity is coupled with increased systemic levels of PEPD that act as a pathogenic trigger of AT fibrosis and IR. Thus, PEPD produced by macrophages might serve as a biomarker of AT fibro-inflammation and could represent a therapeutic target for AT fibrosis and obesity-associated IR and type 2 diabetes.

SARM1 Promotes Photoreceptor Degeneration in an Oxidative Stress Model of Retinal Degeneration

SARM1 (sterile alpha and armadillo motif-containing protein) is a highly conserved Toll/IL-1 Receptor (TIR) adaptor with important roles in mediating immune responses. Studies in the brain have shown that SARM1 plays a role in induction of neuronal axon degeneration in response to a variety of injuries. We recently demonstrated that SARM1 is pro-degenerative in a genetic model of inherited retinopathy. This current study aimed to characterise the effect of SARM1 deletion in an alternative model of retinal degeneration (RD) in which the retinal pigment epithelium (RPE) fragments following administration of oxidising agent, sodium iodate (NaIO3), leading to subsequent photoreceptor cell death. Following administration of NaIO3, we observed no apparent difference in rate of loss of RPE integrity in SARM1 deficient mice compared to WT counterparts. However, despite no differences in RPE degeneration, photoreceptor cell number and retinal thickness were increased in Sarm1–/– mice compared to WT counterparts. This apparent protection of the photoreceptors in SARM1 deficient mice is supported by an observed decrease in pro-apoptotic caspase-3 in the photoreceptor layer of Sarm1–/– mice compared to WT. Together these data indicate a pro-degenerative role for SARM1 in the photoreceptors, but not in the RPE, in an oxidative stress induced model of retinal degeneration consistent with its known degenerative role in neurons in a range of neurodegenerative settings.

Development of an intracellular quantitative assay to measure compound binding kinetics

Contemporary drug discovery typically quantifies the effect of a molecule on a biological target using the equilibrium-derived measurements of IC50, EC50, or KD. Kinetic descriptors of drug binding are frequently linked with the effectiveness of a molecule in modulating a disease phenotype; however, these parameters are yet to be fully adopted in early drug discovery. Nanoluciferase bioluminescence resonance energy transfer (NanoBRET) can be used to measure interactions between fluorophore-conjugated probes and luciferase fused target proteins. Here, we describe an intracellular NanoBRET competition assay that can be used to quantify cellular kinetic rates of compound binding to nanoluciferase-fused bromodomain and extra-terminal (BET) proteins. Comparative rates are generated using a cell-free NanoBRET assay and by utilizing orthogonal recombinant protein-based methodologies. A screen of known pan-BET inhibitors is used to demonstrate the value of this approach in the investigation of kinetic selectivity between closely related proteins.

Search for magnetic monopoles produced via the Schwinger mechanism

Electrically charged particles can be created by the decay of strong enough electric fields, a phenomenon known as the Schwinger mechanism¹. By electromagnetic duality, a sufficiently strong magnetic field would similarly produce magnetic monopoles, if they exist². Magnetic monopoles are hypothetical fundamental particles that are predicted by several theories beyond the standard model^3-7 but have never been experimentally detected. Searching for the existence of magnetic monopoles via the Schwinger mechanism has not yet been attempted, but it is advantageous, owing to the possibility of calculating its rate through semi-classical techniques without perturbation theory, as well as that the production of the magnetic monopoles should be enhanced by their finite size^8,9 and strong coupling to photons^2,10. Here we present a search for magnetic monopole production by the Schwinger mechanism in Pb-Pb heavy ion collisions at the Large Hadron Collider, producing the strongest known magnetic fields in the current Universe¹¹. It was conducted by the MoEDAL experiment, whose trapping detectors were exposed to 0.235 per nanobarn, or approximately 1.8 × 10⁹, of Pb-Pb collisions with 5.02-teraelectronvolt center-of-mass energy per collision in November 2018. A superconducting quantum interference device (SQUID) magnetometer scanned the trapping detectors of MoEDAL for the presence of magnetic charge, which would induce a persistent current in the SQUID. Magnetic monopoles with integer Dirac charges of 1, 2 and 3 and masses up to 75 gigaelectronvolts per speed of light squared were excluded by the analysis at the 95% confidence level. This provides a lower mass limit for finite-size magnetic monopoles from a collider search and greatly extends previous mass bounds.