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Dimensionality reduction using the t-Distributed Stochastic Neighbor Embedding (t-SNE) algorithm has emerged as a popular tool for visualizing high-parameter single-cell data. While this approach has obvious potential for data visualization it remains unclear how t-SNE analysis compares to conventional manual hand-gating in stratifying and quantitating the frequency of diverse immune cell populations. We applied a comprehensive 38-parameter mass cytometry panel to human blood and compared the frequencies of 28 immune cell subsets using both conventional bivariate and t-SNE-guided manual gating. t-SNE analysis was capable of stratifying every general cellular lineage and most sub-lineages with high correlation between conventional and t-SNE-guided cell frequency calculations. However, specific immune cell subsets delineated by the manual gating of continuous variables were not fully separated in t-SNE space thus causing discrepancies in subset identification and quantification between these analytical approaches. Overall, these studies highlight the consistency between t-SNE and conventional hand-gating in stratifying general immune cell lineages while demonstrating that particular cell subsets defined by conventional manual gating may be intermingled in t-SNE space.

Electoral violence has become a recurring challenge in Africa, posing a significant threat to democracy, political stability, and human security. This paper explores the relationship between state security and electoral violence in the African context and draws valuable lessons for Ghana. The objectives of this study include investigating the causes and dynamics of electoral violence in Africa, analyzing the role of state security agencies in preventing and mitigating electoral violence, assessing lessons that Ghana could learn from other African countries' experiences, and proposing recommendations to enhance state security and prevent electoral violence in Ghana's Fourth Republic. The paper adopted an explanatory sequential mixed method design. The approach combined the quantitative data analysis and qualitative data collection through literature reviews, interviews, and focus group discussions. By identifying causes and dynamics of electoral violence, assessing the performance of state security agencies, and drawing lessons from successful strategies employed in other African countries. The aim of the study is to add to the existing literature the development of effective measures for ensuring peaceful and fair elections in Ghana. The results reveal a positive and direct relationship between electoral violence and democratization. Furthermore, the research discloses a positive and direct relationship between electoral violence and state security. Finally, the results reveal that state security has an intermediating effect between electoral violence and democratization. The research findings will inform policymakers, election officials, and relevant stakeholders in designing strategies to reduce electoral violence and promote democratic processes in Ghana and across the African continent. Based on these, the study recommends the provision of trusted security, a constitutional review, and an increment of trust in the electoral space.

Mitochondrial (mt) sequences from cytochrome oxidase subunit I to the subunit II gene (COI, COII) in crustacean talitrid amphipods were analyzed. The COI-NC-COII organizations and preliminary results, based on both COI-COII nucleotide and amino-acid sequence indicated monopoly of these talitrid taxa.

IntroductionGlioblastoma (GBM) is a highly aggressive malignant tumor of the central nervous system that displays varying molecular and morphological profiles, leading to challenging prognostic assessments. Stratifying GBM patients according to overall survival (OS) from H&E-stained whole slide images (WSI) using advanced computational methods is challenging, but with direct clinical implications.MethodsThis work is focusing on GBM (IDH-wildtype, CNS WHO Gr.4) cases, identified from the TCGA-GBM and TCGA-LGG collections after considering the 2021 WHO classification criteria. The proposed approach starts with patch extraction in each WSI, followed by comprehensive patch-level curation to discard artifactual content, i.e., glass reflections, pen markings, dust on the slide, and tissue tearing. Each patch is then computationally described as a feature vector defined by a pre-trained VGG16 convolutional neural network. Principal component analysis provides a feature representation of reduced dimensionality, further facilitating identification of distinct groups of morphology patterns, via unsupervised k-means clustering.ResultsThe optimal number of clusters, according to cluster reproducibility and separability, is automatically determined based on the rand index and silhouette coefficient, respectively. Our proposed approach achieved prognostic stratification accuracy of 83.33% on a multi-institutional independent unseen hold-out test set with sensitivity and specificity of 83.33%.DiscussionWe hypothesize that the quantification of these clusters of morphology patterns, reflect the tumor's spatial heterogeneity and yield prognostic relevant information to distinguish between short and long survivors using a decision tree classifier. The interpretability analysis of the obtained results can contribute to furthering and quantifying our understanding of GBM and potentially improving our diagnostic and prognostic predictions.

Abstract Organoids are becoming increasingly relevant in biology and medicine for their physiological complexity and accuracy in modeling human disease. To fully assess their biological profile while preserving their spatial information, spatiotemporal imaging tools are warranted. While previously developed imaging techniques, such as four‐dimensional (4D) live imaging and light‐sheet imaging have yielded important clinical insights, these technologies lack the combination of cyclic and multiplexed analysis. To address these challenges, bioorthogonal click chemistry is applied to display the first demonstration of multiplexed cyclic imaging of live and fixed patient‐derived glioblastoma tumor organoids. This technology exploits bioorthogonal click chemistry to quench fluorescent signals from the surface and intracellular of labeled cells across multiple cycles, allowing for more accurate and efficient molecular profiling of their complex phenotypes. Herein, the versatility of this technology is demonstrated for the screening of glioblastoma markers in patient‐derived human glioblastoma organoids while conserving their viability. It is anticipated that the findings and applications of this work can be broadly translated into investigating physiological developments in other organoid systems.

Introduction Arteriovenous shunting has been described in glioblastoma multiforme (GBM), also known as WHO grade 4 astrocytoma. This case report demonstrates the diagnostic dilemma of GBM, which was subsequently found to have macrovascular arteriovenous shunting. The lesion was initially treated as an ischemic stroke for months. Methods A 65‐year‐old‐man with a past medical history of hypertension, hyperlipidemia, and diabetes presented to a community hospital in February 2023 with worsening left‐sided weakness. The patient started having left‐sided weakness around December 2023, but no work‐up had been completed. The exam was notable for spastic hemiparesis. Results At the time of initial presentation, a non‐contrasted head computed tomography (NCHCT) was interpreted as normal. Magnetic resonance imaging (MRI) of the brain showed diffusion restriction and fluid attenuated inversion recovery (FLAIR) hyperintensity in the right corona radiata and was interpreted as a subacute right corona radiata and gangliocapsular infarct. Computed tomography angiogram (CTA) of the head and neck was unremarkable. He was discharged on aspirin and a high‐intensity statin. He re‐presented in April 2023 with sepsis and was found to have multiple pressure ulcers; his left‐sided weakness had worsened despite a course of inpatient rehabilitation. A repeat NCHCT demonstrated hyperdensity within the suspected infarct, interpreted as hemorrhagic transformation. The next day, he was found to be difficult to arouse and dysarthric. He was subsequently transferred to our institution for further management. On arrival, a CTA of the head and neck was performed, which suggested that the previously described hyperdensity was possibly a venous varix, and a thrombosed developmental venous anomaly or arteriovenous malformation was suggested. The patient then underwent an MRI brain with and without contrast, which noted that there was an increase in size of a heterogeneously enhancing mass centered in the posterior right basal ganglia/corona radiata with extension into right thalamus, right cerebral peduncle, and posterior right body of corpus callosum. The MRI findings were most consistent with GBM. Given the diagnostic uncertainty, the patient underwent a cerebral angiogram, which demonstrated a hypervascular posterior right basal ganglia mass with arteriovenous shunting from the middle cerebral artery to the internal cerebral veins. Shortly after, the patient underwent a brain biopsy, which demonstrated GBM (IDH‐wildtype, WHO grade 4). The patient was ultimately transitioned to hospice. Conclusion This case highlights the presence of macrovascular shunting in GBM. Intratumoral arteriovenous shunting in GBM has been described, and when present, can lead to delay in treatment due to the broadened differential diagnosis. This patient was first treated for an ischemic stroke with subsequent hemorrhagic transformation. Further imaging suggested a venous varix, thrombosed developmental venous anomaly, or arteriovenous malformation, but the combination of the cerebral angiogram and MRI led to the definitive diagnosis in a patient with a short survival period.

Introduction Treatment-resistant hypertension (RH), defined as uncontrolled blood pressure (≥140/90 mm Hg) despite treatment with ≥3 medications of different classes (including diuretics) at optimal doses, is associated with poor prognosis and an elevated risk of end-organ damage. In areas where HIV is endemic, such as sub-Saharan Africa, the risk of hypertension is high in people living with HIV. It remains unknown if HIV infection further increases the risk of RH. This study seeks to determine the association between HIV and RH as well as investigate other factors associated with RH in hypertensive Malawian adults.Methods and analysis A case–control study will be conducted among adult hypertensive patients attending a clinic at a referral hospital in Malawi. The cases will be hypertensive patients with a confirmed diagnosis of RH. For each case, two controls (hypertensive patients without RH), frequency matched for age group and sex, will be selected from among hospital clients attending the same hypertension clinic as the case. In both groups, HIV status will be ascertained. Additionally, information on other potential risk factors of RH, such as chronic kidney disease, obesity, hypercholesteraemia, diabetes, smoking, alcohol use, antiretroviral therapy regimen and duration, will be collected in both cases and controls. For each of the potential risk factors, ORs will be calculated to quantify the strength of their association with RH. In a multivariate analysis, conditional logistic regression will be used to assess the independent association between HIV and RH as well as the influence of the other potential drivers of RH.Ethics and dissemination This protocol has been approved by the College of Medicine Research Ethics Committee (COMREC) in Malawi (P.05/22/3637). Findings from this study will be disseminated through a peer-reviewed publication in an open-access international journal. Furthermore, anonymised data will be available on request from the authors.

Research has been conducted on well-separated populations of the butterfly Danaus chrysippus. The authors have examined the congruence between the nuclear genotype and haplotype within the species from both allopatric and sympatric ranges in an attempt to gather evidence for sexual isolation of these populations, and they present the results.

Metastatic medullary thyroid cancer (MTC) is a rare but often aggressive thyroid malignancy with a 5-year survival rate of less than 40% and few effective therapeutic options. Adoptive T cell immunotherapy using chimeric antigen receptor (CAR)-modified T cells (CAR Ts) is showing encouraging results in the treatment of cancer, but development is challenged by the availability of suitable target antigens. We identified glial-derived neurotrophic factor (GDNF) family receptor alpha 4 (GFRα4) as a putative antigen target for CAR-based therapy of MTC. We show that GFRα4 is highly expressed in MTC, in parafollicular cells within the thyroid from which MTC originates, and in normal thymus. We isolated two single-chain variable fragments (scFvs) targeting GFRα4 isoforms a and b by antibody phage display. CARs bearing the CD3ζ and the CD137 costimulatory domains were constructed using these GFRα4-specific scFvs. GFRα4-specific CAR Ts trigger antigen-dependent cytotoxicity and cytokine production in vitro, and they are able to eliminate tumors derived from the MTC TT cell line in an immunodeficient mouse xenograft model of MTC. These data demonstrate the feasibility of targeting GFRα4 by CAR T and support this antigen as a promising target for adoptive T cell immunotherapy and other antibody-based therapies for MTC.

IntroductionSpinal osteoblastomas are primary benign bone tumors most commonly presenting as diffuse back pain in young adults. Rarely, spinal osteoblastoma is associated with ossification of the ligamentum flavum (OLF), a form of ectopic bone formation, which can present with myelopathy. This report highlights a unique case of a patient with spinal osteoblastoma, associated OLF, and thoracic myelopathy.Case DescriptionThe patient presented with subtle myelopathy consisting of mid-thoracic back pain, paresthesias, and gait instability. Imaging findings were suggestive of spinal osteoblastoma with multifocal OLF. The patient was consented for thoracic decompression and stabilization at the T6-10 levels. Histopathology confirmed osteoblastoma with associated OLF. At follow up, the patient’s neurological symptoms had completely resolved.ConclusionThis case describes management for a rare presentation of osteoblastoma with associated OLF and myelopathy. Surgeons should be wary of disproportionate neurological compromise when spinal osteoblastoma is associated with OLF. Further study is required to elucidate the pathogenesis of this condition.