A novel form of macropinocytosis mediates ultra-rapid transfer of pathological alpha- synuclein to lysosomes

The nervous system spread of alpha-synuclein fibrils leads to Parkinson′s disease (PD) and other synucleinopathies, yet the mechanisms underlying internalization and cell-to-cell transfer are enigmatic. Here we use confocal and superresolution microscopy, subcellular fractionation and electron microscopy of immunogold labelled alpha-synuclein pre-formed fibrils (PFF) to demonstrate that this toxic protein species enters cells using a novel form of ultra-rapid macropinocytosis with transfer to lysosomes in as little as 2 minutes, an unprecedented cell biological kinetic for lysosomal targeting. PFF uptake circumvents classical endosomal pathways and is independent of clathrin. Immunogold-labelled PFF are seen at the highly curved inward edge of membrane ruffles, in newly formed macropinosomes, and in lysosomes. While many of the fibrils remain in lysosomes that continue to take up PFF for hours, a portion are transferred to neighboring naive cells on the external face of vesicles, likely exosomes. These data indicate that PFF uses a novel internalization mechanism as a component of cell-to-cell propagation.

BRAIN Surgical Tissue for Advanced Tumour models in Precision medicine: Developing the BRAIN-STAT pathway

Aims There are approximately four thousand neuro-oncology procedures in the UK per annum. Many of these result in tissue and biofluid specimens that are surplus to diagnostic requirement and can be collected as standard of clinical care. However, developing technologies and treatments for precision medicine require access to a range of individualised biospecimens paired with deep clinical phenotyping data. Here, we present Brain Surgical Tissue for Advanced Tumour Models (BRAINSTAT) programme, an infrastructure that has been established between Queen Elizabeth Hospital, Birmingham and the University of Birmingham, to collect, structure and store these resources and also maximise their value for research over the long-term. Using this approach our aim is to provide high-quality, annotated resources to help develop novel treatments for patients with brain tumours. Method BRAINSTAT infrastructure allows: Prospective consent Biospecimens, including tumour tissue (brain and other primary in the case of metastasis), cyst fluid, dura, skin, CSF, blood (matched “germ-line” and for circulating cell free tumour DNA analysis), urine and saliva can be collected. Consent for long term follow-up, is either via clinic or NHS digital. More limited consent for non-oncological neurosurgical cohorts (e.g. epilepsy or vascular) and healthy volunteers allow healthy access-tissue and biofluids to be collected. B. Rapid transfer of fresh surgical tissue samples: Strong collaborative links and close physical proximity between operating theatre and laboratory allows rapid transfer of biospecimens minimising transit time. C. Standardised annotation across disciplines The RedCAP database system allows granular control over data-access, and each specialist research team is provided access only to the sub-sections relevant to them. All users must have Good Clinical Practice certification and GDPR training, prior to access of the BRAINSTAT database. Results Between 25/11/2019-16/03/2020 and 27/07/2020-16/11/2020, 65 patients were consented for BRAINSTAT at the weekly neurosurgical oncology clinic. (Recruitment gaps due to the SARS-COVID 19 pandemic). Pathological diagnosis of surplus tissue collected included: 37 high grade glioma, 3 low grade glioma and 16 brain metastasis including: (6 lung, 6 breast, 2 colorectal, 1 oesophageal, 1 endometrial). Meningioma (5 WHO I; 1 WHO III) 1 patient undergoing anterior temporal lobectomy for hippocampal sclerosis contributed access tissue from the lateral neocortex. 1 patient had a non- neoplastic, non-diagnostic sample. All patients had matched “germ-line” blood samples. Median time from resection to arrival in the laboratory was 10 minutes (range 4-31). Standardised operating protocols to optimise this have been developed. Glioblastoma and breast-brain metastasis tumourspheres and cerebral organoids are currently being validated. Conclusion Despite the challenges of the pandemic we have established a viable tissue pipeline from neurosurgical operating theatre to our university laboratories. We are developing clinically annotated human brain tumour cell lines, stem cells and 3D organoid models, principally for commonly encountered brain tumours such as glioma and metastasis. The research sets the foundation for a multitude of downstream applications including: - Building more complex organoid cultures e.g. by including other cell types such as healthy brain cells and endothelial cells allowing future experiments to more accurately model tumour growth. - Developing high-throughput, patient-specific drug screens of novel drugs and drug combinations using these 3D tumour models aiming to more effectively treat tumour proliferation and spread. These patient avatars will help inform and test more “stratified” personal medical treatments and will provide opportunities to allow earlier intervention with the aim of improving survival, coupled with a better quality of life.

41 Low Flow Priapism as A Complication of Covid-19 Infection

On 12 March 2020 the World Health Organisation (WHO) declared a pandemic of SARS-COV-2(Covid 19). We report a case of a 58-year-old man who presented with dyspnoea, pyrexia and a dry cough. Upon admission he was noted to be in a severe Type 1 Respiratory Failure with Bi-lateral pulmonary infiltrates suggestive of Covid 19 infection. Rapid transfer to ITU ensued with Intubation, Ventilation and Inotropic support. Priapism was noted a day into admission which was subsequently aspirated by the Urology team, achieving detumescence. Priapism is a state of persistent penile erection that continues for 4 hours beyond sexual stimulation. We describe the role of thrombosis, dysregulation of the clotting cascade and acute disseminated intravascular coagulation (DIC) as shared pathologies in priapism and Covid 19 infection. We highlight the importance of vigilance for extra-pulmonary manifestations of Covid-19 and feel that the pro-thrombotic phenomena exhibited by Covid-19 infection affects distal vasculature in the same manner as Low Flow Priapism and hence explains why our patient suffered from this particular urological complication

Acute abdominal surgical presentations in children

Surgical conditions affecting the abdomen in children can be associated with significant morbidity and mortality if they are not recognised and managed appropriately. It is therefore important that the correct diagnosis is made quickly, and the appropriate intervention is initiated in a timely manner and, if necessary, rapid transfer is made to a specialist paediatric surgical facility. This article provides an overview of the different surgical presentations encountered in children, and outlines the most important points in the history, examination and management of such cases, whether encountered in the emergency setting or in the community. Two illustrative case studies have been included to demonstrate how these emergencies may present in clinical practice.

CpG Transformer for imputation of single-cell methylomes

Motivation: The adoption of current single-cell DNA methylation sequencing protocols is hindered by incomplete coverage, outlining the need for effective imputation techniques. The task of imputing single-cell (methylation) data requires models to build an understanding of underlying biological processes. Current approaches compress intercellular methylation dependencies in some way and, hence, do not provide a general-purpose way of learning interactions between neighboring CpG sites both within- and between cells. Results: We adapt the transformer neural network architecture to operate on methylation matrices through the introduction of a novel 2D sliding window self-attention. The obtained CpG Transformer displays state-of-the-art performances on a wide range of scBS-seq and scRRBS-seq datasets. Furthermore, we demonstrate the interpretability of CpG Transformer and illustrate its rapid transfer learning properties, allowing practitioners to train models on new datasets with a limited computational and time budget. Availability and Implementation: CpG Transformer is freely available at https://github.com/gdewael/cpg-transformer.

Evolution of the Prefrontal Cortex in the Hominins

When body weight is taken into account, there was a rapid expansion of the brain during the evolution of the hominins, with the greatest increase occurring from around 400,000 years ago. After this time there is evidence of the bulging of the frontal lobe indicating the further expansion of the prefrontal (PF) cortex. Many selection pressures could have influenced these changes, but all of them involve a change in environment. This could occur via climatic change, via changes in the ecosystem, by migration, or by changes in the cultural environment. The cultural environment includes technology such as stone tool making, cooperation in hunting, and the improvements in communication that this required. The adaptation to new environments requires the solution of new problems, and this was aided by the ability of the PF cortex to support rapid transfer from one problem to another.

Improving Cyclability of Lithium Metal Anode via Constructing Atomic Interlamellar Ion Channel for Lithium Sulfur Battery

Uniform migration of lithium (Li) ions between the separator and the lithium anode is critical for achieving good quality Li deposition, which is of much significance for lithium metal battery operation, especially for Li–sulfur (Li–S) batteries. Commercial separators such as polypropylene or polyethylene can be prepared by wet or dry processes, but they can indeed cause plentiful porosities, resulting in the uneven Li ion stripping/plating and finally the formation of Li dendrites. Thence, we constructed an atomic interlamellar ion channel by introducing the layered montmorillonite on the surface of the separator to guide Li ion flux and achieved stable Li deposition. The atomic interlamellar ion channel with a spacing of 1.4 nm showed strong absorption capacity for electrolytes and reserved capacity for Li ions, thus promoting rapid transfer of Li ions and resulting in even Li ion deposition at the anode. When assembled with the proposed separator, the Coulombic efficiency of Li||Cu batteries was 98.2% after 200 cycles and stable plating/stripping even after 800 h was achieved for the Li||Li symmetric batteries. Importantly, the proposed separator allows 140% specific capacity increase after 190 cycles as employing the Li–S batteries.

Abstract P166: The Primary Stroke Center Transfer Experience to Higher Levels of Care: A Qualitative Study

Background: Transfer times from primary stroke centers/acute stroke ready hospitals (PSCs/ASRHs) to higher levels of care have been shown to be excessive in many cases, promoting some to believe that bypass regulations should be instituted. Yet barriers to rapid transfer remain undescribed in the literature. The purpose of this work is to investigate these issues and the locus of control for transfer time delays. Methods: Six national focus groups with PSC/ASRH staff experienced with stroke transfers were conducted by web conference. Interviews were conducted using pre-scripted open-ended questions; information was recorded, and data were transcribed, for theme identification. Results: Participants were from Northeast, Mid-Atlantic, Southeast, Midwest, and West Coast USA. Data were grouped into 3 main categories representing where transfer problems initiated. Themes emerging within the Internal PSC/ASRH Category were exclusively emergency department (ED) physician focused including knowing how/when to use advanced imaging and telemedicine resources. Of note, all participants were compliant with door-to-CT and treatment time metrics. Within the Transport Category , themes included inadequate time-to-response by ground and air ambulances, and specialty transport costs. Within the Internal Comprehensive Stroke Center (CSC) Category , themes included complex communication, overwhelmed systems, and poor guidance on patient selection. Conclusions: While ED physician contributors to transfer delays are within the control of PSCs/ASRHs, more challenging factors to rapid transfer include factors within transport systems and CSCs themselves. Quantification of these factors is warranted to support transfer system redesign with rapid access to care.

Contribution of Vouacapoua americana fruit-fall to the release of biomass in a lowland Amazon forest

Fruit-fall provides the transfer of biomass and nutrients between forest strata and remains a poorly understood component of Amazon forest systems. Here we detail fruit-fall patterns including those of Vouacapoua americana a Critically Endangered timber species across 25 km2 of lowland Amazon forest in 2016. We use multi-model comparisons and an ensemble model to explain and interpolate fruit-fall data collected in 90 plots (totaling 4.42 ha). By comparing patterns in relation to observed and remotely sensed biomass estimates we establish the seasonal contribution of V. americana fruit-fall biomass. Overall fruit-fall biomass was 44.84 kg ha−1 month−1 from an average of 44.55 species per hectare, with V. americana dominating both the number and biomass of fallen fruits (43% and 64%, number and biomass respectively). Spatially explicit interpolations provided an estimate of 114 Mg dry biomass of V. americana fruit-fall across the 25 km2 area. This quantity represents the rapid transfer by a single species of between 0.01 and 0.02% of the overall above ground standing biomass in the area. These findings support calls for a more detailed understanding of the contribution of individual species to carbon and nutrient flows in tropical forest systems needed to evaluate the impacts of population declines predicted from short (< 65 year) logging cycles.