bluuebunny/crossref_metadata_2025 huggingface dataset:
Unraveling the effect of land use on the bacterioplankton community composition from highly impacted shallow lakes at a regional scale
Authors: Sagua Mara I , Nuozzi Guillermina , Sánchez María L , Huber Paula , Perdomo Santiago , Schiaffino María R
Published: September 2023

Bacterioplankton communities play a crucial role in global biogeochemical processes and are highly sensitive to changes induced by natural and anthropogenic stressors in aquatic ecosystems. We assessed the influence of Land Use Land Cover (LULC), environmental, and geographic changes on the bacterioplankton structure in highly connected and impacted shallow lakes within the Salado River basin, Buenos Aires, Argentina. Additionally, we investigated how changes in LULC affected the limnological characteristics of these lakes at a regional scale. Our analysis revealed that the lakes were ordinated by sub-basins (upper and lower) depending on their LULC characteristics and limnological properties. In coincidence, the same ordination was observed when considering the Bacterioplankton Community Composition (BCC). Spatial and environmental predictors significantly explained the variation in BCC, although when combined with LULC the effect was also important. While the pure LULC effect did not explain a significant percentage of BCC variation, the presence of atrazine in water, an anthropogenic variable linked to LULC, directly influenced both the BCC and some Amplicon Sequence Variants (ASVs) in particular. Our regional-scale approach contributes to understanding the complexity of factors driving bacterioplankton structure and how LULC pervasively affect these communities in highly impacted shallow lake ecosystems from the understudied Southern Hemisphere.
Type II bacterial toxin–antitoxins: hypotheses, facts, and the newfound plethora of the PezAT system
Authors: Chan Wai Ting , Garcillán-Barcia Maria Pilar , Yeo Chew Chieng , Espinosa Manuel
Published: September 2023

Toxin–antitoxin (TA) systems are entities found in the prokaryotic genomes, with eight reported types. Type II, the best characterized, is comprised of two genes organized as an operon. Whereas toxins impair growth, the cognate antitoxin neutralizes its activity. TAs appeared to be involved in plasmid maintenance, persistence, virulence, and defence against bacteriophages. Most Type II toxins target the bacterial translational machinery. They seem to be antecessors of Higher Eukaryotes and Prokaryotes Nucleotide-binding (HEPN) RNases, minimal nucleotidyltransferase domains, or CRISPR–Cas systems. A total of four TAs encoded by Streptococcus pneumoniae, RelBE, YefMYoeB, Phd-Doc, and HicAB, belong to HEPN-RNases. The fifth is represented by PezAT/Epsilon–Zeta. PezT/Zeta toxins phosphorylate the peptidoglycan precursors, thereby blocking cell wall synthesis. We explore the body of knowledge (facts) and hypotheses procured for Type II TAs and analyse the data accumulated on the PezAT family. Bioinformatics analyses showed that homologues of PezT/Zeta toxin are abundantly distributed among 14 bacterial phyla mostly in Proteobacteria (48%), Firmicutes (27%), and Actinobacteria (18%), showing the widespread distribution of this TA. The pezAT locus was found to be mainly chromosomally encoded whereas its homologue, the tripartite omega–epsilon–zeta locus, was found mostly on plasmids. We found several orphan pezT/zeta toxins, unaccompanied by a cognate antitoxin.
Is the Script of a Television Programme the Crux of Being a Legal Performer?
Authors: Saiz García Concepción
Published: September 2023

Last January, the Spanish Supreme Court dismissed the appeal brought against a judgment of the Madrid Provincial Court rejecting the status of ‘actor’ of one of the characters who, together with the announcer, regularly took part in one of the most famous television quiz shows in Spain during the 1990s: ‘Cifras y Letras’. This was a person who acted as an expert teacher of letters whose role consisted basically in constructing long words of nine letters in response to the answers given by the contestants, conversing with them in a very natural and fluent manner on the basis of the script and the informative help which he was given at the time of the production. The inadmissibility of the appeal lodged by ‘the professor’ deprives us of knowing, for the first time, how the concept of performer in Spanish intellectual property law should be interpreted, and even, enjoying all the requirements of an autonomous concept of European Union law, of knowing what the interpretation of the CJEU would be. However, by giving finality to the Audiencia’s judgment, it provides us with the opportunity to delve deeper into this concept by analysing the legal requirements that the artist and her performance must meet. Considering that a protectable performance gives rise to the neighbouring right including the right to receive an equitable remuneration of compulsory collective management for the public communication of the recording containing her performance, clarifying which performances are protected becomes crucial for the proper functioning of the system.
Reducing loneliness in the community. More Together (‘Flere i Fællesskaber’)—a complex intervention in Denmark
Authors: Lasgaard Mathias , Bo Anne F , Nielsen Lise A , Swane Christine E , Qualter Pamela , Christiansen Julie
Published: September 2023

The mounting evidence that loneliness is a determinant of poor health and well-being underpins the need for effective interventions and community action. ‘More Together’ (MoTo) is a large-scale, complex, multi-component and multi-level intervention for community change that addresses loneliness among young people and older adults in Silkeborg Municipality, Denmark. The intervention is inspired by the Collective Impact framework, and it is practice driven and rooted in an extensive cross-sector partnership. This article outlines (i) the organization of the cross-sector partnership, (ii) the structure of the intervention programme, (iii) the key components and activities of the programme and, finally, (iv) the intervention setting and target population. MoTo aims to create new ways to develop, implement and evaluate loneliness interventions. Experiences gained from MoTo hold the potential to transform our understanding of loneliness interventions and may inform and guide future interventions.
From organizational capabilities to corporate performances: at the roots of productivity slowdown
Authors: Costa Stefano , De Santis Stefano , Dosi Giovanni , Monducci Roberto , Sbardella Angelica , Virgillito Maria Enrica
Published: September 2023

This paper is one of the first attempts at empirically identifying organizational capabilities—in this work concerning Italian firms. Together, it proposes new evidence on the link between capabilities and economic performances. To this aim, we employ the Indagine Multiscopo del Censimento Permanente delle Imprese (IMCPI), a survey carried out by the Italian Statistical Office (ISTAT) in 2019, covering the three-year period 2016–2018, addressing a wide range of organizational characteristics including various organizational routines, human resource management (HRM), internationalization strategies, and many others. Our contribution is threefold: first, we aim at detecting what practices and combinations of them result in underlying different capabilities; second, we propose a taxonomy of the production system, both at firm- and sector-level based on the mapping of such capabilities; and third, we study the performance outcomes of different capability taxa in terms of productivity growth.
Detection of clinically relevant carbapenemase encoding genes in carbapenem-resistant Enterobacter cloacae complex and Klebsiella pneumoniae isolated from farmed freshwater fish
Authors: Dwivedi Arti , Kumar Chandra Bhushan , Kumar Anil , Soni Mayank , Sahu Vikash , Awasthi Abhishek , Rathore Gaurav
Published: September 2023

Aims

The present study was aimed to detect clinically relevant carbapenemase encoding genes in carbapenem-resistant Enterobacter cloacae complex (CR-ECC), Klebsiella pneumoniae (CR-KP), and Serratia plymuthica (CR-SP) isolated from farmed freshwater fish.

Methods and results

Out of 243 spatially diverse freshwater fish samples analysed, 5.3% were contaminated with CR-ECC, 1.6% with CR-KP, and 0.4% with CR-SP. The CR-ECC was further identified as E. asburiae (38.5%), E. mori (23.1%), E. cloacae (15.4%), E. hormaechei (15.4%), and E. kobei (7.7%) by 16S rRNA gene sequencing. The CR-ECC were resistant to carbapenems and cefoxitin, whereas CR-KP and CR-SP were multi-drug resistant (MDR). The CR-ECC harboured the carbapenemase gene blaIMI alone or in combination with blaTEM, blaEBC, blaCIT, blaACC, and tet(E). Whereas, CR-KP harboured carbapenemase gene, blaNDM-5 along with blaOXA-48, blaSHV, blaOXA-1, blaCTX-M-15, tet(A), sul1, and qnrB. No carbapenemase-encoding genes were detected in CR-SP. The MLST analysis showed that CR-KP belonged to ST231 and ST1561 lineages, while CR-ECC did not show exact match with any reported STs. The plasmid replicons predominantly detected were IncF and IncI1. Broth mating assays of CR-KP and CR-ECC with recipient Escherichia coli J53 indicated that blaNDM-5 was transferable but not blaIMI.

Conclusion

This study highlights the low-level contamination of carbapenem-resistant Enterobacterales (CRE) harbouring clinically relevant carbapenemase-encoding genes in farmed freshwater fish from India. The CR-ECC of fish origin did not show the potential to spread carbapenem resistance.
Phylogenomics analysis of multidrug-resistant Elizabethkingia anophelis in industrial wastewater treatment plant
Authors: Nascimento Ana Paula Alves , de Farias Beatriz Oliveira , Gonçalves-Brito Andressa Silva , Magaldi Mariana , Flores Claudia , Quidorne Camila Silva , Montenegro Kaylanne S , Bianco Kayo , Clementino Maysa Mandetta
Published: September 2023

Aims

This study investigated the phylogenetic relatedness of multidrug-resistant Elizabethkingia anophelis recovered from an industrial wastewater treatment plant (WWTPi).

Methods and results

The wastewater samples were plated in brain heart infusion agar (4 mg/L ceftazidime, 8 mg/L meropenem, and 2 mg/L polimixin). Four isolates recovered from four stages of WWTPi (influent, aeration, decantation, and treated effluent) were identified and evaluated of susceptibility profiles in the VITEK 2 system. These strains identified as E. meningoseptica were confirmed to be E. anophelis by whole genomic sequencing (Miseq-Illumina) and showed antimicrobial resistance genes of β-lactams, aminoglycosides, and tetracycline’s classes. The ribosomal multilocus sequence typing showed that they belong to the rST 65620 together with clinical strains. The phylogenomic tree revealed the similarity of our strains to those belonging to sublineage 11 and the single nucleotide polymorphism analysis confirmed that they belong to a single clade.

Conclusions

To the best of our knowledge, this is the first study reporting the persistence of multidrug-resistant E. anophelis sublineage 11 along the wastewater treatment.
Efficient calibration for imperfect epidemic models with applications to the analysis of COVID-19
Authors: Sung Chih-Li , Hung Ying
Published: September 2023

The estimation of unknown parameters in simulations, also known as calibration, is crucial for practical management of epidemics and prediction of pandemic risk. A simple yet widely used approach is to estimate the parameters by minimising the sum of the squared distances between actual observations and simulation outputs. It is shown in this paper that this method is inefficient, particularly when the epidemic models are developed based on certain simplifications of reality, also known as imperfect models which are commonly used in practice. To address this issue, a new estimator is introduced that is asymptotically consistent, has a smaller estimation variance than the least-squares estimator, and achieves the semiparametric efficiency. Numerical studies are performed to examine the finite sample performance. The proposed method is applied to the analysis of the COVID-19 pandemic for 20 countries based on the susceptible-exposed-infectious-recovered model with both deterministic and stochastic simulations. The estimation of the parameters, including the basic reproduction number and the average incubation period, reveal the risk of disease outbreaks in each country and provide insights to the design of public health interventions.
Neonate with congenital pulmonary airway malformation concurrent with enteric duplication cyst: a case report of a rare anomaly
Authors: Krishnan Amit , Schmoke Nicholas , Nemeh Christopher , Wu Yeu Sanz , Duron Vincent
Published: September 2023

A congenital pulmonary airway malformation (CPAM) occurring concurrently with an enteric duplication cyst is a rare anomaly. Definitive management for both abnormalities is usually surgical resection. We present the uncommon case of a neonate with a CPAM and ileal duplication cyst, including pre-natal and post-natal workup. The patient was brought to the operating room for laparoscopic duplication cyst excision at 3 months of age. The patient returned to the operating room for a thoracoscopic right lower lobectomy at five months of age. This case presents a rare congenital anomaly with the concurrent presentation of a CPAM and enteric duplication cyst, with both being successfully excised minimally invasively.
Characterization of intracellular membrane structures derived from a massive expansion of endoplasmic reticulum (ER) membrane due to synthetic ER-membrane-resident polyproteins
Authors: Sandor Andras , Samalova Marketa , Brandizzi Federica , Kriechbaumer Verena , Moore Ian , Fricker Mark D , Sweetlove Lee J
Published: September 2023

The endoplasmic reticulum (ER) is a dynamic organelle that is amenable to major restructuring. Introduction of recombinant ER-membrane-resident proteins that form homo oligomers is a known method of inducing ER proliferation: interaction of the proteins with each other alters the local structure of the ER network, leading to the formation large aggregations of expanded ER, sometimes leading to the formation of organized smooth endoplasmic reticulum (OSER). However, these membrane structures formed by ER proliferation are poorly characterized and this hampers their potential development for plant synthetic biology. Here, we characterize a range of ER-derived membranous compartments in tobacco and show how the nature of the polyproteins introduced into the ER membrane affect the morphology of the final compartment. We show that a cytosol-facing oligomerization domain is an essential component for compartment formation. Using fluorescence recovery after photobleaching, we demonstrate that although the compartment retains a connection to the ER, a diffusional barrier exists to both the ER and the cytosol associated with the compartment. Using quantitative image analysis, we also show that the presence of the compartment does not disrupt the rest of the ER network. Moreover, we demonstrate that it is possible to recruit a heterologous, bacterial enzyme to the compartment, and for the enzyme to accumulate to high levels. Finally, transgenic Arabidopsis constitutively expressing the compartment-forming polyproteins grew and developed normally under standard conditions.
Aeromedical Evacuation, the Expeditionary Medicine Learning Curve, and the Peacetime Effect
Authors: Hall Andrew , Olsen Cara , Dribben William , Glaser Jacob , Hanson Matthew
Published: September 2023

Introduction

Organizational proficiency increases with experience, which is known as a learning curve. A theoretical peacetime effect occurs when knowledge and skills degrade during peacetime. In this study, the intertheater evacuation system was examined for evidence of a military learning curve and peacetime effect.

Materials and Methods

Data on medical evacuations from U.S. Central Command occurring between January 1, 2003, and December 31, 2022, were acquired from the TRANSCOM Regulating and Command & Control Evacuation System. Priority mission evacuation time corresponding to peak periods of activity in Iraq and Afghanistan and minimal activity in Afghanistan was analyzed. Any reduction or increase in the delivery time of casualties would be considered a change in proficiency.

Results

There was a marginal monthly decline of 0.019 days (27.4 min) to perform a priority evacuation from Iraq (95% confidence interval [CI], 0.009 to 0.028 days, P < .001) and a decline of 0.010 days (14.4 min) from Afghanistan (95% CI, 0.003 to 0.016 days, P = .004) over 40 months from peak monthly average times. There was a monthly marginal increase in priority evacuation average time from Afghanistan of 0.008 days (11.5 min) (95% CI, 0.005 to 0.011, P < .001) between January 2013 and December 2020. The number of monthly evacuations estimated to maintain or improve monthly average evacuation time is approximately 50.

Conclusions

An intertheater aeromedical evacuation system increased in proficiency during periods of conflict and declined during relative peacetime. There is evidence of a peacetime effect on intertheater aeromedical evacuation.
The galaxy cluster AC114 – II. Stellar populations and the mass–metallicity relation
Authors: Saviane Ivo , Yegorova Irina , Proust Dominique
Published: September 2023

We investigate the mass–metallicity relation (MZR)for galaxies in the Abell cluster AC114 from 7 h of VIMOS/MR data collected at the European Southern Observatory-Very Large Telescope in 2009. The dynamical analysis completed in our previous paper allowed us to select cluster members, whose spectra are here analysed with stellar population synthesis models. Active and passive galaxies are identified based on the presence/absence of the [O ii] λ3727, [O iii] λλ4959, 5007 and/or Hβ emission lines, depending on the galaxy redshift. We find that active galaxies have lower average masses than passive ones, and have lower average metallicities. The MZR of the cluster is found to be steeper than that for galaxies in the local universe.
PREOPERATIVE BRAIN IRRADIATION IN GLIOBLASTOMA (POBIG TRIAL): FEASIBILITY AND EVALUATION OF TREATMENT RESPONSE IN ENHANCING AND NON-ENHANCING REGIONS
Authors: Waqar Mueez , Roncaroli Federico , Djoukhadar Ibrahim , Withington Lisa , Golby Christopher , Whitehurst Philip , Hewitt Lauren , Forte Gabriella , O’leary Claire , Colaco Rovel , Bailey Matthew , Karabatsou Konstantina , D’Urso Pietro , McBain Catherine , Coope David , Borst Gerben
Published: September 2023

AIMS

Patients with glioblastoma have dismal outcomes and there is an urgent need for new treatment modalities. The POBIG trial is the first to evaluate the safety and feasibility of single-fraction preoperative radiotherapy for newly diagnosed glioblastoma. We report the results from our first dose arm.

METHOD

POBIG is a phase I radiotherapy dose and volume escalation trial. The first dose arm received 8Gy preoperative radiotherapy to a maximum irradiation volume of 30cm3. The irradiation field included enhancing and non- enhancing FLAIR hyperintense regions judged as highest risk for remaining as postoperative residuum. Part of the tumour remained unirradiated (<2Gy) with a margin for diagnostic sampling. Surgical resection took place within 1 week. Patients underwent diffusion/perfusion MRI scans before/after preoperative radiotherapy.

RESULTS

Two female and one male patient aged 61, 67 and 45 years, respectively, were enrolled. Preoperative radio- therapy was delivered at a dose of 8Gy to an irradiation volume of 7-30cm3. Near-total surgical resection was performed 2-3 days after preoperative radiotherapy treatment. Pathological examination of irradiated areas showed necrosis including fibrinoid necrosis of vessel walls. There was an increase in Ktrans permeability in both irradiated enhancing tumour (0.097,0.150) and unirradiated enhancing tumour (0.077,0.147) 24-hours after treatment. In contrast, no obvious changes were noted in irradiated (0.002,0.002) and unirradiated (0.002,0.004) non-enhancing FLAIR hyperintense regions or reference unirradiated contralateral white matter (0.000,0.000).

CONCLUSIONS

Preoperative radiotherapy is feasible in newly diagnosed glioblastoma. Very early radiotherapy changes manifest in enhancing tumour regardless of radiotherapy dose, evident as increased permeability and radiation- induced tumour necrosis.
NANO-OMICS FOR BLOOD BIOMARKER DISCOVERY IN GLIOBLASTOMA
Authors: Liu Anita , Hadjidemetriou Marilena , Kisby Thomas
Published: September 2023

AIMS

Glioblastoma (GBM) remains one of the most aggressive cancers with an average survival of only 12-15 months. Current diagnostic methods are burdensome and ineffective, underscoring an urgent need to improve early detection and monitoring. The application of ‘liquid-biopsy’ markers holds great promises however, despite technological advances, to date there are no clinically used blood-based biomarkers for GBM. We have recently introduced the ‘Nano-Omics’ paradigm, which utilises nanoparticles (NPs) as scavenging platforms to capture and enrich disease-associated analytes from biological fluids for omics analyses. In this study, we utilised the Nano-Omics pipeline coupled with brain tissue mass spectrometry-based proteomics, to unveil GBM specific protein biomarker candidates.

METHOD

We exploited the spontaneous interaction of nanoparticles with blood proteins to comprehensively analyse the blood proteome of GL261 glioma-bearing C57BL/6J mice. Tumoural and peritumoural brain tissue originated from the same animals were also collected, micro-dissected and analysed by label free mass spectrometry in order to correlate the nanoparticle-enriched blood-circulating proteome with the tumour tissue proteome.

RESULTS

Our data revealed a number of GBM-specific biomarker candidates in blood even at low tumour burden, followed by validation in a human GBM clinical cohort. Furthermore, the peritumoural region of glioblastoma GBM displayed unique proteomic profiling, shedding light on the mechanism behind GBM infiltration and recurrence.

CONCLUSIONS

Our work highlights the importance of integrating blood and brain tissue proteomics and opens up new possibilities for further validation of the proteomic signatures discovered with the potential for further development of a much-needed blood test for GBM early detection and monitoring.
A NOVEL THERAPEUTICS ACCELERATOR TO SUPPORT A STRONGER BRAIN TUMOUR TREATMENT PIPELINE
Authors: Huskens Nicky , Aitken Charlotte , Bushby Katie
Published: September 2023

AIMS

Despite several encouraging pre-clinical studies, few therapeutics make it to successful human trials. There is a need for a stronger new treatment pipeline to improve outcomes for patients with brain tumours. The Tessa Jowell Brain Cancer Mission have launched the Brain Tumour Research Novel Therapeutics Accelerator (BTR- NTA) to provide bespoke advice and support to scientists and help position their therapeutic along a realistic pathway to clinical trials

METHOD

The BTR-NTA programme is supported by an international committee of brain tumour, pre-clinical science, and pharmaceutical experts who meet twice yearly to review up to five novel brain tumour therapeutics. Both academic and industry applicants, at any stage of pre-clinical or clinical work, can apply and submit their work to date before meeting with the BTR-NTA committee to discuss their therapeutic and progress. The committee then provides a written feedback report with advice and recommendations on next steps. The committee will also facilitate connections with industry partners and funders where possible.

RESULTS

It is hoped that BTR-NTA will provide benefits for the whole brain tumour community by: increasing the number of brain tumour therapeutics reaching patients; providing applicants with constructive feedback so that avoidable pitfalls can be overcome; strengthening international relationships between academics, industry, government, and regulatory bodies; and de-risking investment into brain tumour therapeutics for funders.

CONCLUSIONS

The first BTR-NTA meeting will be held in November 2023, with applications opening mid-2023.
DEMOGRAPHICS, GENETICS, AND EPIGENETICS INflUENCE THE LESION DISTRIBUTION OF GLIOMA
Authors: Ruffle James , Mohinta Samia , Brandner Sebastian , Hyare Harpreet , Nachev Parashkev
Published: September 2023

AIMS

Tumour heterogeneity is increasingly recognized as a major obstacle to therapeutic innovation in neuro- oncology. Gliomas typically exhibit a spectrum of genetic mutations, reflecting multiple, potentially complex molecular interactions, and vary widely in their imaging appearances across size, morphology, texture, anatomical distribution, and many other spatial properties. This multifaceted diversity obscures the relationship be- tween tumour genotypic and imaging features, and their joint influence on disease evolution and treatment susceptibility. Though opaque to simple statistical methods, it may nonetheless be accessible to models with the expressivity to capture complex interactions between many different factors.

METHOD

Studying an international sample of 4064 IDH-wildtype glioblastoma, IDH-mutant oligodendroglioma and astrocytoma, deploying an in-house developed state-of-the-art lesion segmentation model, here we map the characteristic distribution of tumour tissue components across the brain and link their spatial properties lesion genetics and epigenetics.

RESULTS

We identify radical differences in tumour spatial topology related not only to diagnosis, but also age, sex, and genetic/epigenetic markers inclusive of TERT, EGFR, and MGMT methylation status. Lesions were equally common across left and right cerebral hemispheres, but significantly larger at presentation when right-sided (p<0.0001), indicating these lesions present later. Both glioblastoma and astrocytoma were commonly temporally based, though oligodendroglioma were often frontal. EGFR amplification was more common in right temporal lesions, whilst MGMT methylation and TERT appeared more bilateral.

CONCLUSIONS

Our results reveal the deep topological structure of gliomas, enabling richer, more closely individuating phenotyping, the development of more robust predictive models of treatment and prognosis, and illuminating multi- modal associations of potential mechanistic significance.
RADIOMICS TO PREDICT THE RESPONSE OF BRAIN METASTASES TO STEREOTACTIC RADIOTHERAPY
Authors: Rozati Hamoun , Angelini Elsa , Williams Matthew
Published: September 2023

AIMS

Radiomics converts routinely obtained medical imaging into mineable, high-dimensionality data. We assessed its utility for incorporation into a multivariate model to predict the likelihood of response of brain metastases (BMs) to stereotactic radiotherapy (SRT).

METHOD

Patients treated with SRT over a ten-year period for BMs at three tertiary centres were retrospectively analyzed. SRT planning MRI scans were pre-processed, and radiomic features were extracted from each BM using PyRadiomics software. Follow up scans were analyzed for response and quantified by a modification of the Response Assessment in Neuro-Oncology Brain Metastases criteria. A radiomic signature predictive of BM response was created by a stepwise process involving correlation coeffcients and a binary least absolute shrinkage and se- lection operator regression analysis. A clinical predictive multivariate model for predicting response was com- pared against a combination clinical/radiomic model by McFadden’s pseudo-R-squared test.

RESULTS

520 patients were included contributing a total of 1891 BMs. 1131 radiomic features were extracted from each BM. 12 features were used to construct a radiomic signature. Mean dose and BM volume were independent predictors of response in both the clinical and radiomics models. The radiomic signature was an independent prognostic predictor for response in the radiomic model (HR=1.095-1.231). Goodness of fit for predicting response was greater in the radiomics model (McFadden’s pseudo-R-squared score 0.243 vs 0.211), and statistically significant by likelihood ratio test (p=0.021).

CONCLUSIONS

This multi-centre retrospective analysis created a unique radiomic signature for predicting BM response to SRT and is the first study to incorporate clinical factors. A prospective validation study is planned.
INCIDENCE AND PREDICTORS OF CLINICALLY SIGNIfiCANT ACUTE AND LATE TREATMENT-RELATED TOXICITY AFTER STEREOTACTIC RADIOSURGERY IN 4 OR MORE BRAIN METASTASES
Authors: Parikh Shefali , Alluri Usha , Benghiat Helen , Heyes Geoff , Meade Sara , Sawlani Vijay , Chavda Swarupsinh , Watts Colin , Hickman Mitchell , Sanghera Paul
Published: September 2023

AIMS

Selected patients with multiple brain metastases can benefit from stereotactic radiosurgery (SRS). Brain V12 (total brain volume receiving 12Gy including target) can predict for late toxicity in single target benign disease, however their value remains uncertain for multiple brain metastases. We report the incidence and evaluate predictors of toxicity in patients with 4 or more brain metastases treated with single fraction SRS.

METHOD

226 patients with 2160 treated metastases from 2014-21 were retrospectively studied. Severe acute toxicity, and symptomatic late toxicity (new/progressive neurological symptoms ≥ 3 months post SRS) with MRI changes suggestive of treatment-effect were analysed. Kaplan-Meier method and cumulative incidence function was used to assess survival and toxicity respectively.

RESULTS

Median number of metastases per patient was 6 (range 4-41) and median V12 was 11.3cc (range 1.5- 45.2cc). Median overall survival (mos.) was 7.6 months. Absolute incidence of acute grade 3/4 cerebral oedema/haemorrhage was 4.9%. The subgroup developing late SRS-related toxicity (16 patients) had a higher mos. than those without toxicity (25mos vs 5 mos., p <0.002). 9/16 (56%) patients developed Grade 3 or 4 toxicity. 82/226 patients survived >12 months and cumulative incidence function of symptomatic SRS-related late toxicity in this group was 4% at 1 year and 9.5% at 2 years.

CONCLUSIONS

Within the limits of data available a brain V12 value did not meaningfully predict for late SRS related toxicity in patients with multiple brain metastases. The cumulative incidence of clinically relevant late toxicity remains <10% at 2 years despite accepting a high median V12 to treat these patients.
DEVELOPMENT OF GLIEXP; A HIGH-THROUGHPUT EX VIVO DRUG SCREENING PLATFORM FOR GLIOBLASTOMA
Authors: Gagg Hannah , Williams Sophie , Rominiyi Ola , Danson Sarah , Collis Spencer , Wells Greg
Published: September 2023

AIMS

With diminishing returns and common clinical failure rates from traditional preclinical and animal-based drug discovery strategies, emphasis is being placed on alternative drug discovery platforms, such as ex vivo approaches. Such approaches represent a departure from both preclinical animal-based models and more traditional clinical-based strategies and aim to address intra/inter-patient variability at an earlier stage of drug discovery. Additionally, they could also offer precise treatment stratification for patients within a week of surgery to direct a tailored treatment course. One tumour group that could significantly benefit from such ex vivo approaches are high-grade gliomas, which exhibit extensive heterogeneity, cellular plasticity and therapy- resistant glioma stem cell (GSC) niches, and where historic preclinical models have failed to generate new therapies leading to 50-year stagnant dire survival rates of around 15 months post-diagnosis.

METHOD

We have developed and optimized a high-throughput ex vivo drug screening platform; GliExP, which maintains GSC populations using immediately dissociated fresh surgical tissue.

RESULTS

As a proof-of-concept for GliExP, we have optimized standard-of-care chemoradiotherapy responses which can correctly predict MGMT status based on Temozolomide sensitivity. We have screened 30+ small molecule therapeutics and preclinical compounds against 18 different patient’s tumours, including multi-region spatial het- erogeneity sampling from several individual tumours. Drug responses are further correlated to transcriptomic and genetic profiles.

CONCLUSIONS

Our data provides a strong basis to build upon GliExP to incorporate combination-based oncology therapeutics in tandem with standard-of-care therapies as an important preclinical model to triage experimental therapeutics for clinical translation, delivering rapid identification of effective treatment strategies for individual gliomas.
M6A RNA MODIfiCATION AND A DRIVER OF CELLULAR PLASTICITY AND INTRA-TUMOURAL HETEROGENEITY IN GLIOBLASTOMA
Authors: Deacon Simon , Radhi Masar , Rowlinson Jonathan , Knight Helen , Kim Dong-Hyun , Smith Stuart
Published: September 2023

AIMS

The immense cellular plasticity of glioblastoma is a barrier to successful therapy. N6-methyladenosine (m6A) methylation of RNA is increasingly recognised as a key driver of cellular differentiation. Crucially, it is a reversible and dynamic modification that alters cellular phenotype via the regulation of mRNA metabolism. We hypothesise that m6A methylation mediates glioblastoma plasticity, regulating transcriptional networks and thus influencing cellular adaptation under different microenvironmental conditions. Our aims are to assess whether total m6A levels and m6A-regulatory gene expression are responsive to change in oxygenation levels and cellular confluency. Furthermore, we aim to characterise the spatial distribution of m6A in 3D cell culture models.

METHOD

We have investigated m6A levels in patient-derived cell lines from the invasive region of adult glioblastoma. Mass spectrometry and anti-m6A immunofluorescence confocal microscopy was used to quantify total m6A levels. We have compared total m6A levels in normoxic versus hypoxic culture conditions and in low versus high confluency 2D cell culture, including cell migration during a scratch assay. We have measured expression levels of key m6A-regulatory genes using rtPCR.

RESULTS

Total m6A levels and regulatory gene expression were not significantly different in normoxic versus hypoxic conditions. However, m6A levels were decreased in high confluency versus low confluency conditions. We will further characterise the spatial distribution of m6A in 3D cell culture models using immunofluorescence confocal microscopy.

CONCLUSIONS

We demonstrate a degree of variability in m6A levels in response to micro-environmental conditions, such as cellular confluency. These findings indicate a role for m6A in tumoral heterogeneity and cellular adaptation.
QUANTIFYING THE NEED FOR A BEST SUPPORTIVE CARE CLINIC
Authors: Al-Munaer Marwan , Holman Sam , Wilby Emma , Brodbelt Andrew
Published: September 2023

AIMS

Patients newly diagnosed with high-grade primary brain tumour and poor performance status discussed in the Multidisciplinary team (MDT) may not be felt to benefit from active treatment and their uptake in clinic is poor. We aimed to explore the volume of patients not being treated in our region, their survival rates, and the reasons for the limited requests for clinical review.

METHOD

Data was obtained from medical records of identified patients from April 2021 to April 2022. This included demographics, presentation, diagnosis date, clinic visits, and date of death.

RESULTS

78 patients were referred for suspected high-grade primary brain tumours and selected for best supportive care by the MDT. Only 73 (64% male) were diagnosed radiologically with a high-grade primary tumour and the rest were excluded.

Median age was 79 years (range 74 – 84). The commonest presenting symptoms were confusion (53%), falls (29%), and dysphasia (25%). Median survival time after diagnostic scan was 67 days (range 34 – 107). Survival rates at 1, 3, 6, and 12 months were 82%, 33%, 8%, and 1%, respectively.

28 patients (38%) were seen in clinic. 13 had been provided with the option to attend by letter. The median duration from referral to clinic was 9 days (range 7 – 14).

CONCLUSIONS

Only a third of non-treatable patients with newly diagnosed high-grade primary brain tumours are being seen in the clinic. Communication between the MDT and the patient offering this service is poor. Longer term survivors suggest an incorrect diagnosis who may benefit from further review.
ALTERNATIVE LENGTHENING OF TELOMERES (ALT) IS SEEN IN A PROPORTION OF OLIGODENDROGLIOMAS AND IT IS ASSOCIATED WITH A WORSE PROGNOSIS
Authors: Ng Ho Keung , Li Kay K K , Shi Zhi-Feng
Published: September 2023

AIMS

Oligodendrogliomas are well known to be mutated for TERTp, which is enigmatically a diagnostic criteria for molecular glioblastoma by WHO2021. It is generally believed that gliomas that are TERTp negative maintain their telomere lengths by means of Alternative Lengthening of Telomeres (ALT) which is usually reflected by mutations of ATRX. Oligodendrogliomas are known to be non-mutated for ATRX unlike astrocytomas. TERT re-arrangement has also been shown to be an alternative way of TERT activation.

METHOD

We evaluated 112 oligodendrogliomas of both Grades 2 (n=87) and 3 (n=25) (all IDH-mutant, 1p19q co-deleted and 93% TERTp mutated by Sanger sequencing) by FISH for ALT, MYC, PDGFRA, EGFR , CDKN2A HD, and +7/-10, the latter events being associated with malignant transformation in low-grade gliomas.

RESULTS

40 cases (35.7%) showed ALT and ALT positivity was associated with worse PFS (p=.024) and remained an in- dependent prognosticator in multivariate analysis. Amplification was found in MYC (6.3%), PDGFRA (10.7%), EGFR (0.8%), CDKN2A HD (6.25%) and +7/-10 (0%) and they had no prognostic significance, likely due to low occurrences. ALT was found to be associated with MYC amplification (p=.004). ALT-positive cases were further evaluated by FISH for TERT re-arrangement, and targeted panel DNA sequencing. CIC mutation (62.1%) was as- sociated with shorter OS in Grade 2 tumours (p=.023) and was the only significant finding from panel sequencing. TERT re-arrangement was only seen in 10.7% and had no prognostic significance.

CONCLUSIONS

ALT is seen in a proportion of oligodendrogliomas in spite of TERTp mutations and is associated with a worse prognosis.
ROLE OF THE TRANSCRIPTIONAL ELONGATION FACTOR SPT6 AS A MODULATOR OF RAD52 IN GLIOBLASTOMA TUMOURS
Authors: Aguilar-Morante Diana , Hamerlik Petra
Published: September 2023

AIMS

Glioblastoma (GBM) is the deadliest and most common primary brain tumour with median survival rates of less than two years. Inter- and intra-tumoral heterogeneity, cellular plasticity and de-regulated signalling pathways are plausible causes of resistance to existent therapies in GBM. As current therapies offer only limited survival benefits, the identification and validation of new approaches in glioblastoma management is of the highest importance

METHOD

• In silico analysis, RNA sequencing analysis after SPT6 depletion and analysis of R-loop formation after RAD52 depletion.

• Patient-Derived Xenografts and primary human glioblastoma cells

RESULTS

Our recent findings show significantly higher RAD52 mRNA levels in malignant gliomas compared to normal brain, where its levels negatively correlate with GBM patient survival. Experimental data show that the inhibition of RAD52 by 6-Hydroxy-DL-Dopa (6OH-Dopa) impairs GBM cell survival due to increased replication- transcription collisions leading to the accumulation of DNA damage. Transcriptional elongation factor SPT6 has previously been named an essential gene in GBM. We find that loss of SPT6 decreases the expression of HR proteins BRCA1, RAD51 and RAD52. RAD52 binds to single-strand DNA (ssDNA), plays a crucial role in most HR events, and restarts collapsed replication forks in response to oncogene-induced replication stress. Further investigation into the role of RAD52 showed depletion of RAD52 results in an increase of R-loops increasing genomic instability and DNA damage.

CONCLUSIONS

Based on our findings, we hypothesize that SPT6 modulates RAD52, which acts as a sensor of R-loops and plays a crucial role in R-loops’ resolution.
DEVELOPING 3D PRINTING MODELS OF BRAIN TUMOURS
Authors: Ballesteros-Cillero Rafael , Valli Jessica , Melchels Ferry P W , Leslie Nicholas R
Published: September 2023

AIMS

To succeed in clinical trials for glioblastoma we need in vitro models capable of more faithfully replicating dis- ease biology and more accurately predicting patient drug responses. To this end, new bioprinting technologies have the potential to biofabricate clinically relevant biomimetic tissues which can accelerate drug discovery and additionally serve as a platform for personalized medicine.

METHOD

We evaluated the effect of individual biomaterials and combinations of biomaterials, including decellularised pig brain extracellular matrix (dECM), fibrin, gelatin-methacryloyl (GelMA), hyaluronic acid-methacrylate (HAMA), Matrigel and alginate, on the proliferation and invasion of aggressive brain cancer cells (U87) in vitro. Cell viability was assessed using propidium iodide. Invasiveness was studied employing confocal microscopy. Data generated from Z-stacks was analysed using ImageJ to determine the size and circularity of cells.

RESULTS

Although Matrigel supports rapid cell proliferation and invasion, it has mechanical properties unsuited to bio- printing. In contrast, HAMA displays a pronounced shear-thinning behaviour and rapid controllable photo- crosslinking. Combinations of HAMA-fibrin provided results comparable to those seen with Matrigel or HAMA- Matrigel. However, high levels of crosslinking affected these biomaterial mixtures, resulting in a decreased ability of cells to grow and spread.

CONCLUSIONS

Initial results indicate that the addition of fibrin to HAMA promoted the growth and spreading of U87 cells. In further work, we aim to improve our printed constructs by including porcine brain dECM, microglia and recently established cell lines from paediatric patients. The project will test whether these bioprinted models can provide drug testing data with closer results to human disease than current, simpler alternatives.
M6A RNA METHYLATION AS A THERAPEUTIC TARGET IN HIGH GRADE GLIOMA
Authors: Radhi Masar , Rowlinson Jonathan , Halliday Nigel , Kim Dong-Hyun , Deacon Simon , Knight Helen , Smith Stuart
Published: September 2023

AIMS

High grade glioma (HGG) is a devastating brain cancer that has poor prognostic outcomes. N6-methyladenosine (m6A) is the most prevalent mRNA modification. It is co transcriptionally installed by a methyltransferase com- plex composed of METTL3, METTL14 and WTAP. The modification is reversible and erased by FTO and ALKBH5. Here we sought to investigate the functional importance of m6A RNA methylation in the pathogenesis and drug resistance of HGG.

METHOD

To identify the expression of key m6A effectors, RT-qPCR and immunofluorescence were undertaken . The expression of these effectors was modified using siRNA knockdown and small molecules to identify their effects on key transcription factors. The effect of modification on the ability of the cells to form neurospheres was also assessed. Developing chemotherapy-resistant cell lines is undertaking to assess the effect of m6A RNA levels on the ability of HGG cells to adapt to environmental changes. Measuring the m6A level was achieved by developing methylated RNA immunoprecipitation qPCR and LC-MS/MS techniques.

RESULTS

We found that key m6A RNA methylation effectors are highly expressed in HGG cell lines and tissues. LC-MS/MS and immunofluorescence showed an increase in the level of m6A. Genetic and chemical inhibition of METTL3, FTO and WTAP affects the expression of key transcription factors in self-renewal, cell cycle regulation and tumorigenesis. Depletion of these effectors reduces the ability of cells to form neurospheres, increases apoptosis and suppresses invasion.

CONCLUSIONS

These findings suggest the role of RNA methylation in the pathogenesis of HGG and could open a new avenue for developing effective treatment strategies.
BEHAVIOURAL TESTING OF SENSORI-MOTOR FUNCTION IN AWAKE CRANIOTOMY; A LITERATURE REVIEW
Authors: Cooper Sara , Sinha Rohit , Stephenson Elisa , Ewan Seonaid , Mathew Ryan
Published: September 2023

AIMS

Evaluate how sensori-motor (SM) testing is performed in awake craniotomy (AC) in the literature. Compare SM testing methods and their related outcomes.

METHOD

Literature search from 1995- 2019 in OVID Medline, Embase, PsychInfo, CINAHL and Web Of Science using all permutations of MESH terms “brain tumour” “awake craniotomy” “sensory” “motor” “testing”. 11671 articles were screened and 28 included based on suffcient detail of the tasks and intraoperative processes that would allow for evaluation.

RESULTS

SM testing is used to preserve function in AC when tumours involve or neighbour eloquent cortical structures sub serving movement. It is also used to identify subcortical tracts such as corticospinal and frontostriatal, as well as and the negative motor network. There is broad variation in how SM testing is conducted in different centres, with no standardisation. The most common strategies were:

•Simple gross movement of contralateral limbs (n= 17) e.g., hand open/closing.

•Functional movement (n=5) e.g., grasping object

•Standardised tests (n= 3) including the Hand Manipulation Task and Sensory-Motor Profile awake

•Patient at rest observed for positive motor responses or patient reported sensory changes (n= 2).

CONCLUSIONS

Multiple different intra-operative strategies exist for the preservation of sensori-motor function in awake craniotomy. Benefits of the over-arching AC strategy for SM preservation is frequently demonstrated. However, comparison and optimisation between strategies is hindered by heterogenous study objectives and outcomes reported. A core testing and outcome set may be useful to standardise, optimise and compare so that maximal patient benefit and functional preservation can be achieved.
INVESTIGATING THE ROLE OF LIPID DROPLETS IN MEDULLOBLASTOMA TUMOURS
Authors: Cotton Kian , Niklison-Chirou Maria Victoria
Published: September 2023

AIMS

Medulloblastomas (MBs) are the most common paediatric brain tumour which originates in the cerebellum. It is classified into four subgroups named: sonic hedgehog, wingless, Group 3 and Group 4. Current treatment for MBs includes surgery, followed by high levels of chemotherapy and radiotherapy. This treatment regime is highly aggressive for the developing brain and produces several significant side effects. Therefore, research into new treatments or improving those already available is crucial to improving patients of life.

METHOD

It is well-documented that cancer cells have the ability to reprogram their metabolism to support rapid proliferation. These metabolic adaptations will provide the cells with the ability to use alternative sources of energy such as glutamine or lipids. Lipid Droplets (LDs) are highly dynamic cytoplasmic organelles that, under homeostatic conditions, are key in the storage of excess lipids within the cell to provide a buffer against lipotoxicity. Recent research has also begun to describe LDs as more than simple storage molecules but instead as function- ally active organelles. Increases in LD formation have been reported in several cancers such as Glioblastoma

RESULTS

In this study, we observed that aggressive MB cells have significantly more LDs when compared to non- aggressive MB cells. Further, oleic acid stimulation induced LD formation in MB cells. Finally, in silico gene expression analysis was performed to evaluate the expression of multiple components of the de novo lipid synthesis pathway in medulloblastoma.

CONCLUSIONS

Our work demonstrates that aggressive MB cells overexpress LDs and therefore identifies them as a possible novel target for MB treatment.