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Meningiomas are the most common intracranial brain tumours. These tumours are heterogeneous and encompass a wide spectrum of clinical aggressivity. Treatment options are limited to surgery and radiotherapy and have a risk of post-operative morbidities and radiation neurotoxicity, reflecting the need for new therapies. Three-dimensional (3D) patient-derived cell culture models have been shown to closely recapitulate in vivo tumour biology, including microenvironmental interactions and have emerged as a robust tool for drug development. Here, we established a novel easy-to-use 3D patient-derived meningioma spheroid model using a scaffold-free approach. Patient-derived meningioma spheroids were characterised and compared to patient tissues and traditional monolayer cultures by histology, genomics, and transcriptomics studies. Patient-derived meningioma spheroids closely recapitulated morphological and molecular features of matched patient tissues, including patient histology, genomic alterations, and components of the immune microenvironment, such as a CD68 + and CD163 + positive macrophage cell population. Comprehensive transcriptomic profiling revealed an increase in epithelial-to-mesenchymal transition (EMT) in meningioma spheroids compared to traditional monolayer cultures, confirming this model as a tool to elucidate EMT in meningioma. Therefore, as proof of concept study, we developed a treatment strategy to target EMT in meningioma. We found that combination therapy using the MER tyrosine kinase (MERTK) inhibitor UNC2025 and the histone deacetylase (HDAC) inhibitor Trichostatin A (TSA) effectively decreased meningioma spheroid viability and proliferation. Furthermore, we demonstrated this combination therapy significantly increased the expression of the epithelial marker E-cadherin and had a repressive effect on WHO grade 2-derived spheroid invasion, which is suggestive of a partial reversal of EMT in meningioma spheroids., (© 2023. The Author(s).)

Protein A affinity chromatography is a key step in isolation of biotherapeutics (BTs) containing fragment crystallizable regions, including monoclonal and bispecific antibodies. Dynamic binding capacity (DBC) analysis assesses how much BT will bind to a protein A column. DBC reduces with column usage, effectively reducing the amount of recovered product over time. Drug regulatory bodies mandate chromatography resin lifetime for BT isolation, through measurement of parameters including DBC, so this feature is carefully monitored in industrial purification pipelines. High-performance affinity chromatography (HPAC) is typically used to assess the concentration of BT, which when loaded to the column results in significant breakthrough of BT in the flowthrough. HPAC gives an accurate assessment of DBC and how this changes over time but only reports on protein concentration, requires calibration for each new BT analyzed, and can only be used offline. Here we utilized Raman spectroscopy and revealed that this approach is at least as effective as both HPAC and ultraviolet chromatogram methods at monitoring DBC of protein A resins. In addition to reporting on protein concentration, the chemical information in the Raman spectra provides information on aggregation status and protein structure, providing extra quality controls to industrial bioprocessing pipelines. In combination with partial least square (PLS) analysis, Raman spectroscopy can be used to determine the DBC of a BT without prior calibration. Here we performed Raman analysis offline in a 96-well plate format, however, it is feasible to perform this inline. This study demonstrates the power of Raman spectroscopy as a significantly improved approach to DBC monitoring in industrial pipelines., Competing Interests: Declaration of Conflicting InterestsThe authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Genetic referral for Lynch syndrome (LS) exemplifies complex clinical pathways. Identifying target behaviours (TBs) for change and associated barriers requires structured group consultation activities with busy clinicians - consolidating implementation activities whilst retaining rigour is crucial. This study aimed to: i) use process mapping to gain in-depth understandings of site-specific LS testing and referral practices in Australian hospitals and support identification of TBs for change, ii) explore if barriers to identified TBs could be identified through process mapping focus-group data, and iii) demonstrate pandemic-induced transition from in-person to virtual group interactive process mapping methods. LS clinical stakeholders attended interactive in-person or virtual focus groups to develop site-specific "process maps" visually representing referral pathways. Content analysis of transcriptions informed site-specific process maps, then clinical audit data was compared to highlight TBs for change. TBs were reviewed in follow-up focus groups. Secondary thematic analysis explored barriers to identified TBs, coded against the Theoretical Domains Framework (TDF). The transition from in-person to pandemic-induced virtual group interactive process mapping methods was documented. Process mapping highlighted six key areas of clinical practice variation across sites and site-specific TBs for change were identified. Key barriers to identified TBs emerged, categorised to seven TDF domains. Process mapping revealed variations in clinical practices surrounding LS referral between sites. Incorporating qualitative perspectives enhances process mapping by facilitating identification of TBs for change and barriers, providing a pathway to developing targeted interventions. Virtual process mapping activities produced detailed data and enabled comprehensive map development., (© The Author(s) 2023. Published by Oxford University Press on behalf of the Society of Behavioral Medicine.)

Competing Interests: None.

We use terahertz time-domain spectroscopy to study gallium arsenide two-dimensional electron gas samples in external magnetic field. We measure cyclotron decay as a function of temperature from 0.4 to10Kand a quantum confinement dependence of the cyclotron decay time belowT0=1.2K. In the wider quantum well, we observe a dramatic enhancement in the decay time due to the reduction in dephasing and the concomitant enhancement of superradiant decay in these systems. We show that the dephasing time in 2DEG's depends on both the scattering rate and also on the distribution of scattering angles., (© 2023 IOP Publishing Ltd.)

Despite documented disparities with regard to treatment of skin of color (SOC) among dermatology trainees, a consensus has not yet been established as to how to improve trainee experiences with regard to SOC pathology. Our study objective was to systematically review the literature and assess interventions that have been implemented thus far to increase trainee competence and/or confidence in assessing SOC pathology. A systematic review of PubMed, Scopus, and Science Direct in January 2022 was performed, yielding a total of 1097 records. Inclusion of primary literature only resulted in 669 records. After assessing records for relevance to the objective, a total of 3 were included. Two studies assessed interventions among medical students and 1 among dermatology resident physicians. In general, the interventions assessed the effect of a specific SOC curriculum, but varied in how they came up with the curriculum. One study engaged with medical students of color to develop their curriculum, and 1 study retrospectively identified and included images of patients with SOC into a new database that was used for educational purposes. Interventions that engage with SOC communities may be most relevant, whether this is done by using patient data or by allowing leadership with medical students of color. We present a system for future future interventions to engage with medical students of color at their institution to improve trainee experiences with skin of color and long-term recruitment and support of a diverse medical student body to the field of dermatology., Competing Interests: Conflicts of interest None disclosed., (Copyright © 2022 American Academy of Dermatology, Inc. Published by Elsevier Inc. All rights reserved.)

The metal-to-insulator phase transition (MIT) in low-dimensional materials and particularly two-dimensional layered semiconductors is exciting to explore due to the fact that it challenges the prediction that a two-dimensional system must be insulating at low temperatures. Thus, the exploration of MITs in 2D layered semiconductors expands the understanding of the underlying physics. Here we report the MIT of a few-layered MoSe 2 field effect transistor under a gate bias (electric field) applied perpendicular to the MoSe 2 layers. With low applied gate voltage, the conductivity as a function of temperature from 150 K to 4 K shows typical semiconducting to insulating character. Above a critical applied gate voltage, V c , the conductivity becomes metallic ( i.e. , the conductivity increases continuously as a function of decreasing temperature). Evidence of a metallic state was observed using an applied gate voltage or, equivalently, increasing the density of charge carriers within the 2D channel. We analyzed the nature of the phase transition using percolation theory, where conductivity scales with the density of charge carriers as σ ∝ ( n - n c ) δ . The critical exponent for a percolative phase transition, δ ( T ), has values ranging from 1.34 (at T = 150 K) to 2 ( T = 20 K), which is close to the theoretical value of 1.33 for percolation to occur. Thus we conclude that the MIT in few-layered MoSe 2 is driven by charge carrier percolation. Furthermore, the conductivity does not scale with temperature, which is a hallmark of a quantum critical phase transition.

During embryogenesis, haematopoietic and endothelial lineages emerge closely in time and space. It is thought that the first blood and endothelium derive from a common clonal ancestor, the haemangioblast. However, investigation of candidate haemangioblasts in vitro revealed the capacity for mesenchymal differentiation, a feature more compatible with an earlier mesodermal precursor. To date, no evidence for an in vivo haemangioblast has been discovered. Using single cell RNA-Sequencing and in vivo cellular barcoding, we have unravelled the ancestral relationships that give rise to the haematopoietic lineages of the yolk sac, the endothelium, and the mesenchyme. We show that the mesodermal derivatives of the yolk sac are produced by three distinct precursors with dual-lineage outcomes: the haemangioblast, the mesenchymoangioblast, and a previously undescribed cell type: the haematomesoblast. Between E5.5 and E7.5, this trio of precursors seeds haematopoietic, endothelial, and mesenchymal trajectories., (© 2023. The Author(s).)

Cutaneous squamous cell carcinoma (SCC) is the second most common type of skin cancer and accounts for approximately 25% of nonmelanoma skin cancers (NMSC). Although the majority of cutaneous SCC lesions have been treated successfully by surgical excision, cryotherapy, electrodessication, or Mohs micrographic surgery, some locally advanced SCC patients are either inoperable, have been metastasized, or both. In such patients, treatment is more challenging due to limited options. We reviewed the literature to describe the mechanism of anti-PD1 agents in cancer therapy and current PD-1 blockade immunotherapy trials in cutaneous SCC. Currently, cemiplimab is the only anti-PD1 agent approved by the Food and Drug Administration for the treatment of locally advanced or metastatic SCC. This review described other anti-PD1 agents, such as pembrolizumab and nivolumab, that have depicted promising effects in advanced SCC, resulting in reduction of tumor size with minimal adverse effects. Immunotherapy targeting the PD-1-PD-L1 axis must be considered for advanced cutaneous SCC patients that are refractory to first-line of procedural treatment options.

Objective: To investigate the presence, degree, predictors, and trajectory of dysphagia, dysphonia, and dysarthria among adults hospitalized with COVID-19 across the Republic of Ireland (ROI) during the first wave of the pandemic., Study Design: Prospective observational cohort study., Methods: Adults with confirmed COVID-19 who were admitted into 14 participating acute hospitals across ROI and referred to speech and language therapy between March 1st and June 30th , 2020 were recruited. Outcomes obtained at initial SLT evaluation and at discharge were oral intake status (Functional Oral Intake Scale), perceptual voice quality (GRBAS), and global dysarthria rating (Dysarthria Severity Scale)., Results: Data from 315 adults were analyzed. At initial SLT assessment, 84% required modified oral diets, and 31% required tube feeding. There were high rates of dysphonia (42%) and dysarthria (23%). History of intubation (OR 19.959, 95% CI 6.272, 63.513; P = .000), COVID-19 neurological manifestations (OR 3.592, 95% CI 1.733, 7.445; P = .001), and age (OR 1.034; 95% CI 1.002, 1.066; P = .036) were predictive of oral intake status. History of intubation was predictive of voice quality (OR 4.250, 95% CI 1.838, 9.827; P = .001) and COVID-19 neurological manifestations were predictive of dysarthria (OR 2.275; 95% CI 1.162, 4.456; P = .017). At discharge, there were significant improvements in oral intake (Z = -7.971; P = .000), voice quality (Z = -5.971; P = .000), and dysarthria severity (Z = -2.619; P = .009), although need for modified oral intake (59%), dysphonia (23%), and dysarthria (14%) persisted., Conclusion: Dysphagia, dysphonia, and dysarthria were widespread among adults hospitalized with COVID-19 and they persisted for many at discharge. Prompt SLT evaluation is required to minimize complications., Level of Evidence: 3 Laryngoscope, 132:1251-1259, 2022., (© 2021 The Authors. The Laryngoscope published by Wiley Periodicals LLC on behalf of The American Laryngological, Rhinological and Otological Society, Inc.)

The purpose of BRAIN UK (the UK BRain Archive Information Network) is to make the very extensive and comprehensive National Health Service (NHS) Neuropathology archives available to the national and international neuroscience research community. The archives comprise samples of tumours and a wide range of other neurological disorders, not only from the brain but also spinal cord, peripheral nerve, muscle, eye and other organs when relevant. BRAIN UK was founded after the recognition of the importance of this large tissue resource, which was not previously readily accessible for research use. BRAIN UK has successfully engaged the majority of the regional clinical neuroscience centres in the United Kingdom to produce a centralised database of the extensive autopsy and biopsy archive. Together with a simple application process and its broad ethical approval, BRAIN UK offers researchers easy access to most of the national archives of neurological tissues and tumours (http://www.brain-uk.org). The range of tissues available reflects the spectrum of disease in society, including many conditions not covered by disease-specific brain banks, and also allows relatively large numbers of cases of uncommon conditions to be studied. BRAIN UK has supported 141 studies (2010-2020) that have generated 70 publications employing methodology as diverse as morphometrics, genetics, proteomics and methylomics. Tissue samples that would otherwise have been unused have supported valuable neuroscience research. The importance of this unique resource will only increase as molecular techniques applicable to human tissues continue to develop and technical advances permit large-scale high-throughput studies., (© 2021 The Authors. Neuropathology and Applied Neurobiology published by John Wiley & Sons Ltd on behalf of British Neuropathological Society.)

We perform two-dimensional Fourier transform spectroscopy on magneto-excitons in GaAs at magnetic fields and observe Zeeman splitting of the excitons. The Zeeman components are clearly resolved as separate peaks due to the two-dimensional nature of the spectra, leading to a more accurate measurement of the Zeeman splitting and the Landé g factors. Quantum coherent coupling between Zeeman components is observed using polarization dependent one-quantum two-dimensional spectroscopy. We use two-quantum two-dimensional spectroscopy to investigate higher four-particle correlations at high magnetic fields and reveal the role of the Zeeman splitting on the two-quantum transitions. The experimental two-dimensional spectra are simulated using the optical Bloch equations, where many-body effects are included phenomenologically.

Objectives: This study aims to (i) investigate post-extubation dysphagia and dysphonia amongst adults intubated with SARS-COV-2 (COVID-19) and referred to speech and language therapy (SLT) in acute hospitals across the Republic of Ireland (ROI) between March and June 2020; (ii) identify variables predictive of post-extubation oral intake status and dysphonia and (iii) establish SLT rehabilitation needs and services provided to this cohort., Design: A multi-site prospective observational cohort study., Participants: One hundred adults with confirmed COVID-19 who were intubated across eleven acute hospital sites in ROI and who were referred to SLT services between March and June 2020 inclusive., Main Outcome Measures: Oral intake status, level of diet modification and perceptual voice quality., Results: Based on initial SLT assessment, 90% required altered oral intake and 59% required tube feeding with 36% not allowed oral intake. Age (OR 1.064; 95% CI 1.018-1.112), proning (OR 3.671; 95% CI 1.128-11.943) and pre-existing respiratory disease (OR 5.863; 95% CI 1.521-11.599) were predictors of oral intake status post-extubation. Two-thirds (66%) presented with dysphonia post-extubation. Intubation injury (OR 10.471; 95% CI 1.060-103.466) and pre-existing respiratory disease (OR 24.196; 95% CI 1.609-363.78) were predictors of post-extubation voice quality. Thirty-seven per cent required dysphagia intervention post-extubation, whereas 20% needed intervention for voice. Dysphagia and dysphonia persisted in 27% and 37% cases, respectively, at hospital discharge., Discussion: Post-extubation dysphagia and dysphonia were prevalent amongst adults with COVID-19 across the ROI. Predictors included iatrogenic factors and underlying respiratory disease. Prompt evaluation and intervention is needed to minimise complications and inform rehabilitation planning., (© 2021 The Authors. Clinical Otolaryngology published by John Wiley & Sons Ltd.)

Dermatologic disease in patients without housing (NWH) has not been well characterized. We present a retrospective cohort study delineating dermatologic disease in NWH patients and patients with housing (WH) during presentation to the emergency department. A total of 842 medical records were reviewed, with evenly matched NWH and WH patients based on sex, self-identified race and ethnicity, and age. To improve outcomes in this vulnerable population, our study sought to elucidate more information on the morphology of cutaneous disease and highlight disparities in clinical workup.

A previously well 54- year-old woman presented with a short history of diplopia, cognitive decline, hallucinations and hypersomnolence. The patient had progressive deterioration in short-term memory, ocular convergence spasm, tremor, myoclonus, gait apraxia, central fever, dream enactment and seizures. Results of investigations were normal including MRI brain, electroencephalogram, cerebrospinal fluid (CSF, including CSF prion protein markers) and brain biopsy. The patient died from pneumonia and pulmonary embolus. Brain postmortem analysis revealed neuropathological changes in keeping with Fatal familial insomnia (FFI); the diagnosis was confirmed on genetic testing. FFI is caused by an autosomal dominant and highly penetrant pathogenic Prion Protein gene PRNP Although usually familial, fatal insomnia (FI) also occurs in a rare sporadic form. FI is a rare human prion disease with prominent sleep disturbance, autonomic, motor, cognitive and behavioural involvement. Patient management is with best supportive care and early suspected diagnosis allows for timely palliation., Competing Interests: Competing interests: None declared., (© BMJ Publishing Group Limited 2021. No commercial re-use. See rights and permissions. Published by BMJ.)

Background: This sub-study of the Australian Genomics Cardiovascular Genetic Disorders Flagship sought to conduct the first nation-wide audit in Australia to establish the current practices across cardiac genetics clinics., Method: An audit of records of patients with a suspected genetic heart disease (cardiomyopathy, primary arrhythmia, autosomal dominant congenital heart disease) who had a cardiac genetics consultation between 1st January 2016 and 31 July 2018 and were offered a diagnostic genetic test., Results: This audit included 536 records at multidisciplinary cardiac genetics clinics from 11 public tertiary hospitals across five Australian states. Most genetic consultations occurred in a clinic setting (90%), followed by inpatient (6%) and Telehealth (4%). Queensland had the highest proportion of Telehealth consultations (9% of state total). Sixty-six percent of patients had a clinical diagnosis of a cardiomyopathy, 28% a primary arrhythmia, and 0.7% congenital heart disease. The reason for diagnosis was most commonly as a result of investigations of symptoms (73%). Most patients were referred by a cardiologist (85%), followed by a general practitioner (9%) and most genetic tests were funded by the state Genetic Health Service (73%). Nationally, 29% of genetic tests identified a pathogenic or likely pathogenic gene variant; 32% of cardiomyopathies, 26% of primary arrhythmia syndromes, and 25% of congenital heart disease., Conclusion: We provide important information describing the current models of care for genetic heart diseases throughout Australia. These baseline data will inform the implementation and impact of whole genome sequencing in the Australian healthcare landscape., Competing Interests: Declaration of Competing Interest JI receives research grant support from Myokardia, Inc. No additional conflicts of interest to declare., (Crown Copyright © 2021. Published by Elsevier B.V. All rights reserved.)

In February 2019, the American Psychological Association approved a resolution on physical discipline of children by parents that recognized its negative impact on children; called for increased use of more effective, alternate forms of discipline; and highlighted the need for greater access to behavioral parenting intervention for underserved groups. Despite a wealth of empirical evidence supporting these statements and similar resolutions by other influential organizations (e.g., American Academy of Pediatrics, American Professional Society on the Abuse of Children), many challenges exist in providing empirically supported parent training interventions to individuals in need. The current article reviews many barriers to access and implementation of best practices for parents of children and adolescents, including structural barriers to accessing care and factors that interfere with effective delivery of interventions. The review also provides suggestions for clinicians, researchers, and public policy advocates to begin making progress toward reducing and removing these barriers. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Meningioma is the most common primary intracranial tumour, and surgical resection is the main therapeutic option. Merlin is a tumour suppressor protein that is frequently mutated in meningioma. The activity of the E3 ubiquitin ligase complex, CRL4-DCAF1, and the Raf/MEK/ERK scaffold protein Kinase suppressor of Ras 1 (KSR1) are upregulated in Merlin-deficient tumours, which drives tumour growth. Identifying small molecules that inhibit these key pathways may provide an effective treatment option for patients with meningioma. We used meningioma tissue and primary cells derived from meningioma tumours to investigate the expression of DDB1 and Cullin 4-associated factor 1 (DCAF1) and KSR1, and confirmed these proteins were overexpressed. We then used primary cells to assess the therapeutic potential of MLN3651, a neddylation inhibitor which impacts the activity of the CRL family of E3 ubiquitin ligases and the MAPK/ERK kinase (MEK1/2) inhibitor selumetinib. MLN3651 treatment reduced proliferation and activated apoptosis, whilst increasing Raf/MEK/ERK pathway activation. The combination of MLN3651 and the MEK1/2 inhibitor selumetinib prevented the increase in Raf/MEK/ERK activity, and had an additive effect compared with either treatment alone. Therefore, the combined targeting of CRL4-DCAF1 and Raf/MEK/ERK activity represents an attractive novel strategy in the treatment of Merlin-deficient meningioma.

A 23-year-old low-risk primiparous patient, who was 35 weeks pregnant, presented in the emergency department after collapsing at home. Her observations showed severe hypertension with proteinuria. On examination, she had left hemiparesis and was aphasic. Fetal monitoring was reassuring. Initial CT did not reveal any evidence of intracranial pathology. She was stabilised and delivered via emergency caesarean section. Subsequent MRI and CT showed an acute right-sided infarct involving the right middle cerebral artery territory, frontal and parietal regions, and increased mass effect. She was transferred to the nearest neurosurgical centre where she was conservatively managed and discharged home 3 weeks later for continuing rehabilitation. She achieved a good recovery., Competing Interests: Competing interests: None declared., (© BMJ Publishing Group Limited 2019. No commercial re-use. See rights and permissions. Published by BMJ.)

Carbon and other volatiles in the form of gases, fluids or mineral phases are transported from Earth's surface into the mantle at convergent margins, where the oceanic crust subducts beneath the continental crust. The efficiency of this transfer has profound implications for the nature and scale of geochemical heterogeneities in Earth's deep mantle and shallow crustal reservoirs, as well as Earth's oxidation state. However, the proportions of volatiles released from the forearc and backarc are not well constrained compared to fluxes from the volcanic arc front. Here we use helium and carbon isotope data from deeply sourced springs along two cross-arc transects to show that about 91 per cent of carbon released from the slab and mantle beneath the Costa Rican forearc is sequestered within the crust by calcite deposition. Around an additional three per cent is incorporated into the biomass through microbial chemolithoautotrophy, whereby microbes assimilate inorganic carbon into biomass. We estimate that between 1.2 × 10 8 and 1.3 × 10 10 moles of carbon dioxide per year are released from the slab beneath the forearc, and thus up to about 19 per cent less carbon is being transferred into Earth's deep mantle than previously estimated.

Protein aggregation is the underlying cause of many diseases, and also limits the usefulness of many natural and engineered proteins in biotechnology. Better mechanistic understanding and characterization of aggregation-prone states is needed to guide protein engineering, formulation, and drug-targeting strategies that prevent aggregation. While several final aggregated states-notably amyloids-have been characterized structurally, very little is known about the native structural conformers that initiate aggregation. We used a novel combination of small-angle x-ray scattering (SAXS), atomistic molecular dynamic simulations, single-molecule Förster resonance energy transfer, and aggregation-prone region predictions, to characterize structural changes in a native humanized Fab A33 antibody fragment, that correlated with the experimental aggregation kinetics. SAXS revealed increases in the native state radius of gyration, R g , of 2.2% to 4.1%, at pH 5.5 and below, concomitant with accelerated aggregation. In a cutting-edge approach, we fitted the SAXS data to full MD simulations from the same conditions and located the conformational changes in the native state to the constant domain of the light chain (C L ). This C L displacement was independently confirmed using single-molecule Förster resonance energy transfer measurements with two dual-labeled Fabs. These conformational changes were also found to increase the solvent exposure of a predicted APR, suggesting a likely mechanism through which they promote aggregation. Our findings provide a means by which aggregation-prone conformational states can be readily determined experimentally, and thus potentially used to guide protein engineering, or ligand binding strategies, with the aim of stabilizing the protein against aggregation., (Copyright © 2019 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

In addition to standard management for the treatment of the acute phase of spinal cord injury (SCI), implementation of novel neuroprotective interventions offers the potential for significant reductions in morbidity and long-term health costs. A better understanding of the systemic changes after SCI could provide insight into mechanisms that lead to secondary injury. An emerging area of research involves the complex interplay of the gut microbiome and the CNS, i.e., a brain-gut axis, or perhaps more appropriately, a CNS-gut axis. This review summarizes the relevant literature relating to the gut microbiome and SCI. Experimental models in stroke and traumatic brain injury demonstrate the bidirectional communication of the CNS to the gut with postinjury dysbiosis, gastrointestinal-associated lymphoid tissue-mediated neuroinflammatory responses, and bacterial-metabolite neurotransmission. Similar findings are being elucidated in SCI as well. Experimental interventions in these areas have shown promise in improving functional outcomes in animal models. This commensal relationship between the human body and its microbiome, particularly the gut microbiome, represents an exciting frontier in experimental medicine.

Computationally guided semirational design has significant potential for improving the aggregation kinetics of protein biopharmaceuticals. While improvement in the global conformational stability can stabilize proteins to aggregation under some conditions, previous studies suggest that such an approach is limited, because thermal transition temperatures ( T m ) and the fraction of protein unfolded ( f T ) tend to only correlate with aggregation kinetics where the protein is incubated at temperatures approaching the T m . This is because under these conditions, aggregation from globally unfolded protein becomes dominant. However, under native conditions, the aggregation kinetics are presumed to be dependent on local structural fluctuations or partial unfolding of the native state, which reveal regions of high propensity to form protein-protein interactions that lead to aggregation. In this work, we have targeted the design of stabilizing mutations to regions of the A33 Fab surface structure, which were predicted to be more flexible. This Fab already has high global stability, and global unfolding is not the main cause of aggregation under most conditions. Therefore, the aim was to reduce the conformational flexibility and entropy of the native protein at various locations and thus identify which of those regions has the greatest influence on the aggregation kinetics. Highly dynamic regions of structure were identified through both molecular dynamics simulation and B-factor analysis of related X-ray crystal structures. The most flexible residues were mutated into more stable variants, as predicted by Rosetta, which evaluates the ΔΔ G ND for each potential point mutation. Additional destabilizing variants were prepared as controls to evaluate the prediction accuracy and also to assess the general influence of conformational stability on aggregation kinetics. The thermal conformational stability, and aggregation rates of 18 variants at 65 °C, were each examined at pH 4, 200 mM ionic strength, under which conditions the initial wild-type protein was <5% unfolded. Variants with decreased T m values led to more rapid aggregation due to an increase in the fraction of protein unfolded under the conditions studied. As expected, no significant improvements were observed in the global conformational stability as measured by T m . However, 6 of the 12 stable variants led to an increase in the cooperativity of unfolding, consistent with lower conformational flexibility and entropy in the native ensemble. Three of these had 5-11% lower aggregation rates, and their structural clustering indicated that the local dynamics of the C-terminus of the heavy chain had a role in influencing the aggregation rate.

Multifocal necrotising leucoencephalopathy is a rare disorder affecting the central nervous system. It is characterised pathologically by microscopic areas of necrosis with pontine predilection but also involvement of extrapontine regions, including the cerebellum, medulla and cerebral hemispheres. It usually occurs on the background of immunosuppression. Here we describe an immunocompetent patient with a recent history of Salmonella infection who presented with subacute neurological deterioration. At postmortem, she had evidence of multifocal necrotising leucoencephalopathy., Competing Interests: Competing interests: None declared., (© Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.)

Loss of function mutations in the neurofibromatosis Type 2 (NF2) gene, coding for a tumour suppressor, Merlin, cause multiple tumours of the nervous system such as schwannomas, meningiomas and ependymomas. These tumours may occur sporadically or as part of the hereditary condition neurofibromatosis Type 2 (NF2). Current treatment is confined to (radio) surgery and no targeted drug therapies exist. NF2 mutations and/or Merlin inactivation are also seen in other cancers including some mesothelioma, breast cancer, colorectal carcinoma, melanoma and glioblastoma. To study the relationship between Merlin deficiency and tumourigenesis, we have developed an in vitro model comprising human primary schwannoma cells, the most common Merlin-deficient tumour and the hallmark for NF2. Using this model, we show increased expression of cellular prion protein (PrP C ) in schwannoma cells and tissues. In addition, a strong overexpression of PrP C is observed in human Merlin-deficient mesothelioma cell line TRA and in human Merlin-deficient meningiomas. PrP C contributes to increased proliferation, cell-matrix adhesion and survival in schwannoma cells acting via 37/67 kDa non-integrin laminin receptor (LR/37/67 kDa) and downstream ERK1/2, PI3K/AKT and FAK signalling pathways. PrP C protein is also strongly released from schwannoma cells via exosomes and as a free peptide suggesting that it may act in an autocrine and/or paracrine manner. We suggest that PrP C and its interactor, LR/37/67 kDa, could be potential therapeutic targets for schwannomas and other Merlin-deficient tumours.

Space radiation may pose a risk to skeletal health during subsequent aging. Irradiation acutely stimulates bone remodeling in mice, although the long-term influence of space radiation on bone-forming potential (osteoblastogenesis) and possible adaptive mechanisms are not well understood. We hypothesized that ionizing radiation impairs osteoblastogenesis in an ion-type specific manner, with low doses capable of modulating expression of redox-related genes. 16-weeks old, male, C57BL6/J mice were exposed to low linear-energy-transfer (LET) protons (150 MeV/n) or high-LET 56 Fe ions (600 MeV/n) using either low (5 or 10 cGy) or high (50 or 200 cGy) doses at NASA's Space Radiation Lab. Five weeks or one year after irradiation, tissues were harvested and analyzed by microcomputed tomography for cancellous microarchitecture and cortical geometry. Marrow-derived, adherent cells were grown under osteoblastogenic culture conditions. Cell lysates were analyzed by RT-PCR during the proliferative or mineralizing phase of growth, and differentiation was analyzed by imaging mineralized nodules. As expected, a high dose (200 cGy), but not lower doses, of either 56 Fe or protons caused a loss of cancellous bone volume/total volume. Marrow cells produced mineralized nodules ex vivo regardless of radiation type or dose; 56 Fe (200 cGy) inhibited osteoblastogenesis by more than 90% (5 weeks and 1 year post-IR). After 5 weeks, irradiation (protons or 56 Fe) caused few changes in gene expression levels during osteoblastogenesis, although a high dose 56 Fe (200 cGy) increased Catalase and Gadd45 . The addition of exogenous superoxide dismutase (SOD) protected marrow-derived osteoprogenitors from the damaging effects of exposure to low-LET ( 137 Cs γ) when irradiated in vitro, but had limited protective effects on high-LET 56 Fe-exposed cells. In sum, either protons or 56 Fe at a relatively high dose (200 cGy) caused persistent bone loss, whereas only high-LET 56 Fe increased redox-related gene expression, albeit to a limited extent, and inhibited osteoblastogenesis. Doses below 50 cGy did not elicit widespread responses in any parameter measured. We conclude that high-LET irradiation at 200 cGy impaired osteoblastogenesis and regulated steady-state gene expression of select redox-related genes during osteoblastogenesis, which may contribute to persistent bone loss., Competing Interests: The authors declare no conflict of interest.

Superconducting joints are one of the key components needed to make Ag-alloy clad Bi 2 Sr 2 CaCu 2 O 8+x (Bi-2212) superconducting round wire (RW) successful for high-field, high-homogeneity magnet applications, especially for nuclear magnetic resonance (NMR) magnets in which persistent current mode (PCM) operation is highly desired. In this study, a procedure for fabricating superconducting joints between Bi-2212 round wires during coil reaction was developed. Melting temperatures of Bi-2212 powder with different amounts of Ag addition were investigated by differential thermal analysis (DTA) so as to provide information for selecting the proper joint matrix. Test joints of 1.3 mm dia. wires heat treated in 1 bar flowing oxygen using the typical partial melt Bi-2212 heat treatment (HT) had transport critical currents I c of ~900 A at 4.2 K and self-field, decreasing to ~480 A at 14 T evaluated at 0.1 μV/cm at 4.2 K. Compared to the I c of the open-ended short conductor samples with identical 1 bar HT, the I c values of the superconducting joint are ~20% smaller than that of conductor samples measured in parallel field but ~20% larger than conductor samples measured in perpendicular field. Microstructures examined by scanning electron microscopy (SEM) clearly showed the formation of a superconducting Bi-2212 interface between the two Bi-2212 round wires. Furthermore, a Bi-2212 RW closed-loop solenoid with a superconducting joint heat treated in 1 bar flowing oxygen showed an estimated joint resistance below 5×10 -12 Ω based on its field decay rate. This value is sufficiently low to demonstrate the potential for persistent operation of large inductance Bi-2212 coils.

Studies show equal impact of sexual harassment (SH) on men and women, whereas lay perceptions are that women suffer more. We identify the phenomenon of minimization of male suffering (MMS), which occurs when people assume that SH has less effect on men's well-being and which results in the perpetrators of SH on men being evaluated less harshly. To verify whether these effects occur, we conducted two studies in which we presented stories describing acts of sexual coercion (SC, study 1) and SC or financial coercion (FC, study 2) and measured the perceived suffering of victims and the perception of the perpetrators. Both studies showed that female victims were perceived to suffer more from SC and FC and that perpetrators of both acts on women were evaluated more negatively. The results support our hypothesis that the suffering of male victims is minimized as they are perceived to suffer less than women., Competing Interests: Anna Studzińska declares that she has no conflict of interest. Denis Hilton declares that he has no conflict of interest. Funding This study was funded by the Polish Academy of Science (Narodowe Centrum Nauki) grant number 2012/05/N/HS6/03973. Ethical Approval All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards. Informed consent Informed consent was obtained from all individual participants included in the study.

Aims: Sudden unexpected death in epilepsy (SUDEP) is one of the leading causes of death in people with epilepsy. For classification of definite SUDEP, a post mortem (PM), including anatomical and toxicological examination, is mandatory to exclude other causes of death. We audited PM practice as well as the value of brain examination in SUDEP., Methods: We reviewed 145 PM reports in SUDEP cases from four UK neuropathology centres. Data were extracted for clinical epilepsy details, circumstances of death and neuropathological findings., Results: Macroscopic brain abnormalities were identified in 52% of cases. Mild brain swelling was present in 28%, and microscopic pathologies relevant to cause or effect of seizures were seen in 89%. Examination based on whole fixed brains (76.6% of all PMs), and systematic regional sampling was associated with higher detection rates of underlying pathology (P < 0.01). Information was more frequently recorded regarding circumstances of death and body position/location than clinical epilepsy history and investigations., Conclusion: Our findings support the contribution of examination of the whole fixed brain in SUDEP, with high rates of detection of relevant pathology. Availability of full clinical epilepsy-related information at the time of PM could potentially further improve detection through targeted tissue sampling. Apart from confirmation of SUDEP, complete neuropathological examination contributes to evaluation of risk factors as well as helping to direct future research into underlying causes., (© 2015 The Authors. Neuropathology and Applied Neurobiology published by John Wiley & Sons Ltd on behalf of British Neuropathological Society.)

Merlin has broad tumor-suppressor functions as its mutations have been identified in multiple benign tumors and malignant cancers. In all schwannomas, the majority of meningiomas and 1/3 of ependymomas Merlin loss is causative. In neurofibromatosis type 2, a dominantly inherited tumor disease because of the loss of Merlin, patients suffer from multiple nervous system tumors and die on average around age 40. Chemotherapy is not effective and tumor localization and multiplicity make surgery and radiosurgery challenging and morbidity is often considerable. Thus, a new therapeutic approach is needed for these tumors. Using a primary human in vitro model for Merlin-deficient tumors, we report that the Ras/Raf/mitogen-activated protein, extracellular signal-regulated kinase kinase (MEK)/extracellular signal-regulated kinase (ERK) scaffold, kinase suppressor of Ras 1 (KSR1), has a vital role in promoting schwannomas development. We show that KSR1 overexpression is involved in many pathological phenotypes caused by Merlin loss, namely multipolar morphology, enhanced cell-matrix adhesion, focal adhesion and, most importantly, increased proliferation and survival. Our data demonstrate that KSR1 has a wider role than MEK1/2 in the development of schwannomas because adhesion is more dependent on KSR1 than MEK1/2. Immunoprecipitation analysis reveals that KSR1 is a novel binding partner of Merlin, which suppresses KSR1's function by inhibiting the binding between KSR1 and c-Raf. Our proteomic analysis also demonstrates that KSR1 interacts with several Merlin downstream effectors, including E3 ubiquitin ligase CRL4(DCAF1). Further functional studies suggests that KSR1 and DCAF1 may co-operate to regulate schwannomas formation. Taken together, these findings suggest that KSR1 serves as a potential therapeutic target for Merlin-deficient tumors.

In modulation doped quantum wells, the excitons are formed as a result of the interactions of the charged holes with the electrons at the Fermi edge in the conduction band, leading to the so-called "Mahan excitons." The binding energy of Mahan excitons is expected to be greatly reduced and any quantum coherence destroyed as a result of the screening and electron-electron interactions. Surprisingly, we observe strong quantum coherence between the heavy hole and light hole excitons. Such correlations are revealed by the dominating cross-diagonal peaks in both one-quantum and two-quantum two-dimensional Fourier transform spectra. Theoretical simulations based on the optical Bloch equations where many-body effects are included phenomenologically reproduce well the experimental spectra. Time-dependent density functional theory calculations provide insight into the underlying physics and attribute the observed strong quantum coherence to a significantly reduced screening length and collective excitations of the many-electron system.

Background: Breast cancer commonly metastasises to the brain, but little is known about changes in the molecular profile of the brain secondaries and impact on clinical outcomes., Methods: Patients with samples from brain metastases and matched breast cancers were included. Immunohistochemical analysis for oestrogen receptor, progesterone receptor, p27kip1, cyclin D1, epidermal growth factor receptor, insulin like growth factor 1, insulin like growth factor 1 receptor, vascular endothelial growth factor A, transforming growth factor-β and HER2 receptor was performed. Borderline HER2 results were analysed by fluorescent in situ hybridisation. Levels of expression were compared, with review of effect on clinical outcomes., Results: A total of 41 patients were included. Of the patients, 20% had a change in oestrogen receptor or HER2 in their brain metastasis that could affect therapeutic decisions. There were statistically significant rises in brain metastases for p27kip1 (P=0.023) and cyclin D1 (P=0.030) and a fall in vascular endothelial growth factor A (P=0.012). Overall survival from the time of metastasis increased significantly with oestrogen receptor-positive (P=0.005) and progesterone receptor-positive (P=0.013) brain lesions and with a longer duration from diagnosis of the breast primary (P<0.001)., Conclusions: In this cohort there were phenotypic differences in metastatic brain tumours compared with matched primary breast tumours. These could be relevant for aetiology, and have an impact on prognostication, current and future therapies.

We systematically investigate the excitonic dephasing of three representative transition-metal dichalcogenides, namely, MoS&#95;{2}, MoSe&#95;{2}, and WSe&#95;{2} atomic monolayer thick and bulk crystals, in order to gain a proper understanding of the factors that determine the optical coherence in these materials. Coherent nonlinear optical spectroscopy and temperature dependent absorption, combined with theoretical calculations of the phonon spectra, indicate electron-phonon interactions, to be the limiting factor. Surprisingly, the excitonic dephasing, differs only slightly between atomic monolayers and high quality bulk crystals, which indicates that material imperfections are not the limiting factor in atomically thin monolayer samples. The temperature dependence of the electronic band gap and the excitonic linewidth combined with "ab initio" calculations of the phonon energies and the phonon density of states reveal a strong interaction with the E' and E" phonon modes.

The first withdrawal of certain polybrominated diphenyl ethers flame retardants from the US market occurred in 2004. Since then, use of brominated non-PBDE compounds such as bis(2-ethylhexyl)-2,3,4,5-tetrabromophthalate (BEH-TEBP) and 2-ethylhexyl-2,3,4,5-tetrabromobenzoate (EH-TBB) in commercial formulations has increased. Assessing human exposure to these chemicals requires identifying metabolites that can potentially serve as their biomarkers of exposure. We administered by gavage a dose of 500 mg/Kg bw of Uniplex FRP-45 (>95 % BEH-TEBP) to nine adult female Sprague-Dawley rats. Using authentic standards and mass spectrometry, we positively identified and quantified 2,3,4,5-tetrabromo benzoic acid (TBBA) and 2,3,4,5-tetrabromo phthalic acid (TBPA) in 24-h urine samples collected 1 day after dosing the rats and in serum at necropsy, 2 days post-exposure. Interestingly, TBBA and TBPA concentrations correlated well (R (2) = 0.92). The levels of TBBA, a known metabolite of EH-TBB, were much higher than the levels of TBPA both in urine and serum. Because Uniplex FRP-45 was technical grade and EH-TBB was present in the formulation, TBBA likely resulted from the metabolism of EH-TBB. Taken together, our data suggest that TBBA and TBPA may serve as biomarkers of exposure to non-PBDE brominated flame retardant mixtures. Additional research can provide useful information to better understand the composition and in vivo toxicokinetics of these commercial mixtures.

The analytical characterization of biopharmaceuticals is a fundamental step in the early stages of development and prediction of their behavior in bioprocesses. Protein aggregation in particular is a common issue as it affects all stages of product development. In the present work, we investigate the stability and the aggregation kinetics of A33Fab, a therapeutically relevant humanized antibody fragment at a wide range of pH, ionic strength, and temperature. We show that the propensity of A33Fab to aggregate under thermally accelerated conditions is pH and ionic-strength dependent with a stronger destabilizing effect of ionic strength at low pH. In the absence of added salts, A33Fab molecules appear to be protected from aggregation due to electrostatic colloidal repulsion at low pH. Analysis by transmission electron microscopy identified significantly different aggregate species formed at low and high pH. The correlations between apparent midpoints of thermal transitions (Tm,app values), or unfolded mole fractions, and aggregation rates are reported here to be significant only at the elevated incubation temperature of 65 °C, where aggregation from the unfolded state predominates. At all other conditions, particularly at 4-45 °C, aggregation of A33 Fab was predominantly from a native-like state, and the kinetics obeyed Arrhenius behavior. Despite this, the rank order of aggregation rates observed at 45 °C, 23 and 4 °C still did not correlate well to each other, indicating that forced degradation at elevated temperatures was not a good screen for predicting behavior at low temperature.

As a well-known source of nutrition and pleasure, meat plays an important role in most people's diet. However, awareness of the "meat paradox"-the association of liking to eat meat but not wanting to kill animals-often implies the experience of cognitive dissonance. In two studies, focusing on meat production and meat consumption respectively, we examined whether participants used reduction of willingness to eat meat and reduction of mind attribution to food animals as strategies to reduce cognitive dissonance from the meat paradox in the Chinese and French cultural contexts. Focusing on meat production (slaughtering of an animal to produce meat; Study 1, n = 520), participants reported lower willingness to eat beef in a condition that emphasized the slaughter of a cow compared to a condition that presented a diagram of a cow as meat. In addition, French but not Chinese participants attributed less mind to cows when the relation between meat and its animal origin was made salient. Focusing on meat consumption (the transformation of meat into food; Study 2, n = 518), participants reported lower willingness to eat beef and attributed less mind to cows in a condition that emphasized the animal origin of meat compared to a condition that presented a recipe. These results suggest that the use of different strategies to resolve cognitive dissonance from the meat paradox depends on different contexts of the meat-animal link as well as on cultural context., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Amyloidoma is a rare cause for intracranial space-occupying lesions diagnosed on brain imaging. Histology of excised tissue usually reveals the presence of a discrete, λ-light chain secreting plasmacytoma adjacent to an amyloid mass comprising aggregated monoclonal immunoglobulin light chains. We described a patient with intracerebral amyloidoma associated with a localised lymphoplasmacytic lymphoma and no systemic paraproteinaemia, tumour or amyloid deposits., (Copyright © 2015 Elsevier B.V. All rights reserved.)

A 70-year-old man presented with respiratory distress and proximal muscle weakness shortly after biopsy of a left forearm mass. The biopsy showed giant cell myositis, and serological investigations identified a grossly elevated serum creatine kinase level, suggesting skeletal muscle damage. Serum troponin T was also high, but troponin I was normal. Serum antiacetylcholine receptor antibodies were positive, and imaging showed a thymoma. He recovered well following intravenous immunoglobulin and corticosteroids, and later underwent thymectomy. He is currently in sustained remission, with no clinically detectable myasthenia, but subsequently, developed hypogammaglobulinaemia. Neurologists should remember giant cell myositis/myocarditis can occur in patients who have myasthenia gravis with thymoma, as it is potentially fatal, but may respond to immunosuppression., (Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/)

Nonlinear two-dimensional Fourier transform (2DFT) and linear absorption spectroscopy are used to study the electronic structure and optical properties of excitons in the layered semiconductor GaSe. At the 1s exciton resonance, two peaks are identified in the absorption spectra, which are assigned to splitting of the exciton ground state into the triplet and singlet states. 2DFT spectra acquired for co-linear polarization of the excitation pulses feature an additional peak originating from coherent energy transfer between the singlet and triplet. At cross-linear polarization of the excitation pulses, the 2DFT spectra expose a new peak likely originating from bound biexcitons. The polarization dependent 2DFT spectra are well reproduced by simulations using the optical Bloch equations for a four level system, where many-body effects are included phenomenologically. Although biexciton effects are thought to be strong in this material, only moderate contributions from bound biexciton creation can be observed. The biexciton binding energy of ∼2 meV was estimated from the separation of the peaks in the 2DFT spectra. Temperature dependent absorption and 2DFT measurements, combined with "ab initio" theoretical calculations of the phonon spectra, indicate strong interaction with the A1 (') phonon mode. Excitation density dependent 2DFT measurements reveal excitation induced dephasing and provide a lower limit for the homogeneous linewidth of the excitons in the present GaSe crystal.

The dephasing of the Fermi edge singularity excitations in two modulation doped single quantum wells of 12 nm and 18 nm thickness and in-well carrier concentration of ∼4 × 10(11) cm(-2) was carefully measured using spectrally resolved four-wave mixing (FWM) and two-dimensional Fourier transform (2DFT) spectroscopy. Although the absorption at the Fermi edge is broad at this doping level, the spectrally resolved FWM shows narrow resonances. Two peaks are observed separated by the heavy hole/light hole energy splitting. Temperature dependent "rephasing" (S1) 2DFT spectra show a rapid linear increase of the homogeneous linewidth with temperature. The dephasing rate increases faster with temperature in the narrower 12 nm quantum well, likely due to an increased carrier-phonon scattering rate. The S1 2DFT spectra were measured using co-linear, cross-linear, and co-circular polarizations. Distinct 2DFT lineshapes were observed for co-linear and cross-linear polarizations, suggesting the existence of polarization dependent contributions. The "two-quantum coherence" (S3) 2DFT spectra for the 12 nm quantum well show a single peak for both co-linear and co-circular polarizations.

Polyglutamine expansions in the ataxin-2 gene (ATXN2) cause autosomal dominant spinocerebellar ataxia type 2 (SCA2), but have recently also been associated with amyotrophic lateral sclerosis (ALS). We present clinical and pathological features of a family in which a pathological ATXN2 expansion led to frontotemporal lobar degeneration with ALS (FTLD-ALS) in the index case, but typical SCA2 in a son, and compare the neuropathology with a case of typical SCA2. The index case shares the molecular signature of SCA2 with prominent polyglutamine and p62-positive intranuclear neuronal inclusions mainly in the pontine nuclei, while harbouring more pronounced neocortical and spinal TDP-43 pathology. We conclude that ATXN2 mutations can cause not only ALS, but also a neuropathological overlap syndrome of SCA2 and FTLD presenting clinically as pure FTLD-ALS without ataxia. The cause of the phenotypic heterogeneity remains unexplained, but the presence of a CAA-interrupted CAG repeat in the FTLD case in this family suggests that one potential mechanism may be variation in repeat tract composition between members of the same family.

Despite being a canonical presenting feature of mitochondrial disease, the genetic basis of progressive external ophthalmoplegia remains unknown in a large proportion of patients. Here we show that mutations in SPG7 are a novel cause of progressive external ophthalmoplegia associated with multiple mitochondrial DNA deletions. After excluding known causes, whole exome sequencing, targeted Sanger sequencing and multiplex ligation-dependent probe amplification analysis were used to study 68 adult patients with progressive external ophthalmoplegia either with or without multiple mitochondrial DNA deletions in skeletal muscle. Nine patients (eight probands) were found to carry compound heterozygous SPG7 mutations, including three novel mutations: two missense mutations c.2221G>A; p.(Glu741Lys), c.2224G>A; p.(Asp742Asn), a truncating mutation c.861dupT; p.Asn288*, and seven previously reported mutations. We identified a further six patients with single heterozygous mutations in SPG7, including two further novel mutations: c.184-3C>T (predicted to remove a splice site before exon 2) and c.1067C>T; p.(Thr356Met). The clinical phenotype typically developed in mid-adult life with either progressive external ophthalmoplegia/ptosis and spastic ataxia, or a progressive ataxic disorder. Dysphagia and proximal myopathy were common, but urinary symptoms were rare, despite the spasticity. Functional studies included transcript analysis, proteomics, mitochondrial network analysis, single fibre mitochondrial DNA analysis and deep re-sequencing of mitochondrial DNA. SPG7 mutations caused increased mitochondrial biogenesis in patient muscle, and mitochondrial fusion in patient fibroblasts associated with the clonal expansion of mitochondrial DNA mutations. In conclusion, the SPG7 gene should be screened in patients in whom a disorder of mitochondrial DNA maintenance is suspected when spastic ataxia is prominent. The complex neurological phenotype is likely a result of the clonal expansion of secondary mitochondrial DNA mutations modulating the phenotype, driven by compensatory mitochondrial biogenesis.