The Landscape of Randomized Clinical Trial Meta-analyses on Statins for Aneurysmal Subarachnoid Hemorrhage: A Scoping Review

INTRODUCTION

Aneurysmal subarachnoid hemorrhage (aSAH) is a type of non-traumatic SAH that can have detrimental effects on the central nervous system, resulting in severe disability or death.

METHODS

Early nimodipine is currently the only strongly recommended pharmacological treatment that has shown efficacy in improving neurological/functional outcomes in aSAH patients. Whether statin treatment is of benefit to aSAH patients is an issue that has generated considerable interest and debate. In the present scoping review, we mapped and analyzed the available literature on metaanalyses of randomized clinical trials (RCTs) examining the effect of statins on aSAH. Seventeen meta-analyses of RCTs, published between 2008 and 2023, were identified.

RESULTS

Treatments in included meta-analyses were based on various regimens of simvastatin, pravastatin, pitavastatin or atorvastatin for up to 21 days. Eleven of the included reports indicated some beneficial effect of statin treatment, reducing rates of at least one of the following: cerebral vasospasm, delayed cerebral ischemia/delayed ischemic neurologic deficit, mortality or functional/ neurological outcome. In contrast, six meta-analyses, showed no such effects.

CONCLUSION

The limitations reported by several meta-analyses, included low patient numbers or disproportionate representation of patients from certain RCTs, differences in drug treatment, patient diagnostic criteria and outcome evaluation between RCTs, as well as poor data quality or lack of RCTs data. Knowledge of the reported limitations may aid the design of future clinical trials and/or their meta-analyses.

Advances on Liquid Biopsy Analysis for Glioma Diagnosis

Gliomas comprise the most frequent primary central nervous system (CNS) tumors, characterized by remarkable genetic and epigenetic heterogeneity, difficulty in monitoring, and increased relapse and mortality rates. Tissue biopsy is an established method of tumor cell collection and analysis that enables diagnosis, classification of different tumor types, and prediction of prognosis upon confirmation of tumor's location for surgical removal. However, it is an invasive and often challenging procedure that cannot be used for frequent patient screening, detection of mutations, disease monitoring, or resistance to therapy. To this end, the minimally invasive procedure of liquid biopsy has emerged, allowing effortless tumor sampling and enabling continuous monitoring. It is considered a novel preferable way to obtain faster data on potential tumor risk, personalized diagnosis, prognosis, and recurrence evaluation. The purpose of this review is to describe the advances on liquid biopsy for glioma diagnosis and management, indicating several biomarkers that can be utilized to analyze tumor characteristics, such as cell-free DNA (cfDNA), cell-free RNA (cfRNA), circulating proteins, circulating tumor cells (CTCs), and exosomes. It further addresses the benefit of combining liquid biopsy with radiogenomics to facilitate early and accurate diagnoses, enable precise prognostic assessments, and facilitate real-time disease monitoring, aiming towards more optimal treatment decisions.

Exosomes as Novel Diagnostic Biomarkers and Therapeutic Tools in Gliomas

Exosomes constitute small extracellular vesicles that contain lipids, proteins, nucleic acids, and glycoconjugates from the secreted cells and are capable of transmitting signals between cells and coordinating cellular communication. By this means, they are ultimately involved in physiology and disease, including development, homeostasis, and immune system regulation, as well as contributing to tumor progression and neurodegenerative diseases pathology. Recent studies have shown that gliomas secrete a panel of exosomes which have been associated with cell invasion and migration, tumor immune tolerance, potential for malignant transformation, neovascularization, and resistance to treatment. Exosomes have therefore emerged as intercellular communicators, which mediate the tumor-microenvironment interactions and exosome-regulated glioma cell stemness and angiogenesis. They may induce tumor proliferation and malignancy in normal cells by carrying pro-migratory modulators from cancer cells as well as many different molecular cancer modifiers, such as oncogenic transcripts, miRNAs, mutant oncoproteins, etc., which promote the communication of cancer cells with the surrounding stromal cells and provide valuable information on the molecular profile of the existing tumor. Moreover, engineered exosomes can provide an alternative system for drug delivery and enable efficient treatment. In the present review, we discuss the latest findings regarding the role of exosomes in glioma pathogenesis, their utility in non-invasive diagnosis, and potential applications to treatment.

Medial Pulvinar Stimulation in Temporal Lobe Epilepsy: A Literature Review and a Hypothesis Based on Neuroanatomical Findings

While bilateral stimulation of the anterior thalamic nuclei remains the only approved deep brain stimulation (DBS) option for focal epilepsy, two additional thalamic targets have been proposed. Earlier work indicated the potential of centromedian thalamic nucleus stimulation with recent findings highlighting the medial pulvinar nucleus. The latter has been shown to exhibit electrophysiological and imaging alterations in patients with partial status epilepticus and temporal lobe epilepsy. On this basis, recent studies have begun assessing the feasibility and efficacy of pulvinar stimulation, with encouraging results on the reduction of seizure frequency and severity. Building on existing neuroanatomical knowledge, indicating that the medial pulvinar is connected to the temporal lobe via the temporopulvinar bundle of Arnold, we hypothesize that this is one of the routes through which medial pulvinar stimulation affects temporal lobe structures. We suggest that further anatomic, imaging, and electrophysiologic studies are warranted to deepen our understanding of the subject and guide future clinical applications.

Pesticides and tremor: An overview of association, mechanisms and confounders

Pesticides are a heterogeneous class of chemicals mainly used for the protection of crops from pests. Because of their very widespread use, acute or/and chronic exposure to these chemicals can lead to a plethora of sequelae inflicting diseases, many of which involve the nervous system. Tremor has been associated with pesticide exposure in human and animal studies. This review is aimed at assessing the studies currently available on the association between the various types of pesticides/insecticides and tremor, while also accounting for potential confounding factors. To our knowledge, this is the first coherent review on the subject. After appraising the available evidence, we call for more intensive research on this topic, as well as intonate the need of implementing future preventive measures to protect the exposed populations and to reduce potential disabilities and social drawbacks.

Advances on Epigenetic Drugs for Pediatric Brain Tumors

Pediatric malignant brain tumors represent the most frequent cause of cancer-related deaths in childhood. The therapeutic scheme of surgery, radiotherapy and chemotherapy has improved patient management, but with minimal progress in patients' prognosis. Emerging molecular targets and mechanisms have revealed novel approaches for pediatric brain tumor therapy, enabling personalized medical treatment. Advances in the field of epigenetic research and their interplay with genetic changes have enriched our knowledge of the molecular heterogeneity of these neoplasms and have revealed important genes that affect crucial signaling pathways involved in tumor progression. The great potential of epigenetic therapy lies mainly in the widespread location and the reversibility of epigenetic alterations, proposing a wide range of targeting options, including the possible combination of chemoand immunotherapy, significantly increasing their efficacy. Epigenetic drugs, including inhibitors of DNA methyltransferases, histone deacetylases and demethylases, are currently being tested in clinical trials on pediatric brain tumors. Additional novel epigenetic drugs include protein and enzyme inhibitors that modulate epigenetic modification pathways, such as Bromodomain and Extraterminal (BET) proteins, Cyclin-Dependent Kinase 9 (CDK9), AXL, Facilitates Chromatin Transcription (FACT), BMI1, and CREB Binding Protein (CBP) inhibitors, which can be used either as standalone or in combination with current treatment approaches. In this review, we discuss recent progress on epigenetic drugs that could possibly be used against the most common malignant tumors of childhood, such as medulloblastomas, high-grade gliomas and ependymomas.

Transmission of Potato virus Y in Tobacco Plants by Myzus persicae nicotianae and M. persicae s.str

The transmission efficiency of Potato virus Y ^N (PVY^N) from and to tobacco plants by Myzus persicae nicotianae, a tobacco specialist, and M. persicae s.str. (Hemiptera: Aphididae), a generalist, was evaluated. In direct transmission tests, 1,004 spring migrants collected as nymphs from peach and 1,434 wingless females from 12 clonal lineages of both taxa were examined. Both the winged and wingless females were starved before being transferred individually for a 3-min acquisition period on infected plants and then moved to healthy plants for a 10-min inoculation access period. Little variation in transmission efficiency was observed. Although not statistically significant, M. persicae nicotianae was slightly more effective. This may suggest similar genetic properties (e.g., virion receptors in mouthparts) between the taxa in relation to virus transmission. M. persicae s.str. transmitted the virus less efficiently when a shorter inoculation period was given. This may indicate differences in probing behavior during the early phase of host selection. Nevertheless, behavioral differences related to host selection have been found using arena tests with infected and healthy tobacco plants where 180 winged females from each taxon were tested. M. persicae s.str. had significantly higher propensity to transmit PVY^N than M. persicae nicotianae (31.9 versus 15.3%).