Total synthesis and stereochemical assignment of rakicidin F.

Total synthesis of rakicidin F was accomplished in 20 linear steps (0.68% overall yield), which enabled the configural determination of its six stereogenic centers as 2R, 15R, 16R, 17S, 19S, and 21S. The macrolactonization of the rakicidin linear precursor was investigated and the unsuccessful results might be attributed to the steric hindrance near C16-OH.

The well responsiveness of drug-resistant focal seizures in anti-AMPA2 receptor encephalitis to perampanel treatment.

Anti-α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor encephalitis is an anti-neuronal surface antigen autoimmune encephalitis and is relatively rare. Our study evaluated a patient who developed anti-AMPA2 receptor encephalitis with memory deficits and refractory focal seizures as paroxysmal jerking on right face as well as dystonic seizure on right hand. On this patient, the combination treatment of levetiracetam, carbamazepine, and clonazepam, monthly periodic intravenous immunoglobin and immunosuppressive therapies for 5 months was not effective for the focal seizures, while his memory loss was slightly improved. However, adjunctive perampanel treatment led to a rapid relief of seizures. Perampanel is suggested in seizures associated with anti-AMPA receptor encephalitis by directly attenuating nerve hyperexcitability caused by glutamate and Ca2+-permeable GluA4 subunit of AMPA receptors.

Probe Synthesis Reveals Eukaryotic Translation Elongation Factor†1 Alpha†1 as the Anti-Pancreatic Cancer Target of BE-43547A2.

The natural product, BE-43547A2 , decreases pancreatic cancer cell stemness. However, its anticancer molecular mechanisms have not been fully established. Based on structure-activity relationships of BE-43547A2 , we synthesized a probe and investigated its potential targets using an in situ click reaction. We found that BE-43547A2 exerts its anticancer effects by covalently binding the cysteine234 (C234) residue of eukaryotic translation elongation factor 1 alpha 1 (eEF1A1). This binding mode was confirmed by a series of experiments including a xenograft mouse model. We also determined that eEF1A1 plays an important role in regulating pancreatic cancer cell stemness. Analyses of 99 clinical pancreatic cancer samples revealed that eEF1A1 expressions are closely correlated with clinicopathological grade and patient survival. In conclusion, eEF1A1 is involved in pancreatic cancer progression and is therefore, a promising novel covalent target for pancreatic cancer treatment.

Clinical features of patients with anti-leucine-rich glioma inactivated-1 protein associated encephalitis: a Chinese case series.

Purpose: Antibodies against leucine-rich glioma inactivated 1 (LGI1) are associated with limbic encephalitis and faciobrachial dystonic seizures (FBDS). We present a large series of Han Chinese patients for further clinical refinement. Materials and methods: Serum and cerebrospinal fluid samples from patients were tested. Clinical information of patients with serum anti­LGI1antibody positivity was retrospectively reviewed, and descriptive statistical analysis was performed. Results: The median onset age of the 24 patients was 56.9 years. Among these cases, 18 (75%) patients presented with new­onset refractory seizures, 18 (75%) patients had memory deficits, eight (33.3%) patients had a personality changes and five (20.8%) patients had a disturbance of consciousness. FBDS was observed in nine (37.5%) patients and five of them presented with FBDS as the initial symptom. No cancer was detected in any patient by CT scans. Fourteen (58.3%) patients had hyponatremia. Lymphocytic pleocytosis and protein concentration elevation in CSF were detected in four (16.7%) and six (25%) patients, respectively. Twelve (50%) patients showed paroxysmal sharp/spike waves and slow waves on EEG and seven (29.2%) patients showed mesial temporal region abnormalities by MRI scans. All patients received antiepileptic drugs and immunotherapy. After treatments, the modified Rankin scores of all patients were decreased. Conclusions: Our study showed that Han Chinese patients with anti­LGI1 antibody associated encephalitis had prominent clinical manifestations including seizures, memory deficits and FBDS. They showed neurological improvement with timely immunotherapy. Prompt treatments after rapid clinical recognition is important to improve the prognosis of patients.

Ovatodiolides: Scalable Protection-Free Syntheses, Configuration Determination, and Biological Evaluation against Hepatic Cancer Stem Cells.

A concise, scalable, six-step (longest linear sequence) synthetic route to ovatodiolide scaffolds was developed for the first time. This protecting-group-free route features tandem ring-opening metathesis/ring-closing metathesis reactions to install the macrocycle-fused butenolide ring and a tandem allylboration/lactonization to build the α-methylene-γ-lactone. Our syntheses have enabled the determination of the hitherto unknown stereochemical configurations of this family of natural products. Preliminary tests of structure-activity relationships were conducted with four natural ovatodiolides and three analogues. Further assays indicated that the synthetic natural product isoovatodiolide can significantly decrease the population of hepatic cancer stem cells and reduce the tumorsphere-forming capability of HepG2 cells.

Seizure detection: do current devices work? And when can they be useful?

PURPOSE OF REVIEW: The unpredictability and apparent randomness of epileptic seizures is one of the most vexing aspects of epilepsy. Methods or devices capable of detecting seizures may help prevent injury or even death and significantly improve quality of life. Here, we summarize and evaluate currently available, unimodal, or polymodal detection systems for epileptic seizures, mainly in the ambulatory setting. RECENT FINDINGS: There are two broad categories of detection devices: EEG-based and non-EEG-based systems. Wireless wearable EEG devices are now available both in research and commercial arenas. Neuro-stimulation devices are currently evolving and initial experiences of these show potential promise. As for non-EEG devices, different detecting systems show different sensitivity according to the different patient and seizure types. Regardless, when used in combination, these modalities may complement each other to increase positive predictive value. Although some devices with high sensitivity are promising, practical widespread use of such detection systems is still some way away. More research and experience are needed to evaluate the most efficient and integrated systems, to allow for better approaches to detection and prediction of seizures. The concept of closed-loop systems and prompt intervention may substantially improve quality of life for patients and carers.

Long non-coding RNA ENST00462717 suppresses the proliferation, survival, and migration by inhibiting MDM2/MAPK pathway in glioma.

Gliomas are the most common and aggressive primary malignant tumor in the central nervous system, and requires new biomarkers and therapeutic methods. Long noncoding RNAs (lncRNAs) are important factors in numerous human diseases, including cancer. But studies on lncRNAs and gliomas are limited. In this study, we investigated the expression patterns of lncRNAs in 3 pairs of glioma samples and adjacent non-tumor tissues via microarray and selected the most down-regulated lnc00462717 to further verify its roles in glioma. We observed that decreased lnc00462717 expression was associated with the malignant status in glioma. In vitro experiment demonstrated that lnc00462717 overexpression suppressed glioma cell proliferation, survival and migration while knockdown of lnc00462717 had an opposite result. Moreover, we identified MDM2 as a direct target of lnc00462717 and lnc00462717 played a role by partially regulating the MDM2/MAPK pathway. In conclusion, lnc00462717 may function in suppressing glioma cell proliferation, survival, migration and may potentially serve as a novel biomarker and therapeutic target for glioma.

Atypical features of benign rolandic epilepsy in Chinese children: Retrospective study.

BACKGROUND: Benign rolandic epilepsy (BRE) is one of the most common focal epilepsies in childhood, but less typical clinical presentations may lead to misdiagnosis and incorrect treatment. The focus of this study was therefore to retrospectively investigate the less typical features of BRE in Chinese children. METHODS: Data on 316 Chinese children with BRE were collected and analyzed. RESULTS: A total of 7.3% of children complained of tension, fear and terror at the onset of a seizure, and 5.4% had been misdiagnosed with mesial temporal lobe epilepsy. Approximately 12.3% had post-ictal Todd's paresis, with 6.6% having been misdiagnosed and given incorrect treatment. Nineteen children (6%) had neuroradiologic abnormalities, which could lead to a diagnosis of symptomatic epilepsy. Twenty-five patients (8.0%) had cognitive deficits. CONCLUSIONS: Greater recognition of, and further investigation into, the spectrum of BRE are needed.

Automatic seizure detection using Stockwell transform and boosting algorithm for long-term EEG.

Automatic detection of seizures has vital significance for epileptic diagnosis and can efficiently reduce the workload of the medical staff. In this study, a novel seizure detection method based on Stockwell transform is proposed for intracranial long-term EEG data. The Stockwell transform is employed to obtain the time-frequency representation of the EEG signals, and then the power spectral density is calculated in the time-frequency plane to characterize the behavior of EEG recordings. After that, a classifier based on gradient boosting algorithm is used to make the classification. Finally, the postprocessing is utilized on the outputs of the classifier to obtain more stable and accurate detection results, which includes Kalman filter, threshold judgment, and collar technique. The performance of this method is assessed on the publicly available EEG database which contains approximately 533h of intracranial EEG recordings. The experimental results indicate that the proposed method can achieve a satisfactory sensitivity of 94.26%, a specificity of 96.34%, as well as a very short delay time of 0.56s.

Bifurcation and oscillation in a time-delay neural mass model.

The neural mass model developed by Lopes da Silva et al. simulates complex dynamics between cortical areas and is able to describe a limit cycle behavior for alpha rhythms in electroencephalography (EEG). In this work, we propose a modified neural mass model that incorporates a time delay. This time-delay model can be used to simulate several different types of EEG activity including alpha wave, interictal EEG, and ictal EEG. We present a detailed description of the model's behavior with bifurcation diagrams. Through simulation and an analysis of the influence of the time delay on the model's oscillatory behavior, we demonstrate that a time delay in neuronal signal transmission could cause seizure-like activity in the brain. Further study of the bifurcations in this new neural mass model could provide a theoretical reference for the understanding of the neurodynamics in epileptic seizures.

Löffler endocarditis with multiple cerebral embolism.

Idiopathic hypereosinophilic syndrome is an uncommon leukoproliferative systemic disorder characterized by the sustained eosinophilia and target organ damage. We report the case of a 56-year-old man presenting with multiple cerebral embolism, Löffler endocarditis, and hypereosinophilia. This patient also had pleural, bone marrow, and skin involvement. The unique feature was multifocal embolisms in the brain.

Inhibition of NLRP3 inflammasome alleviates cognitive deficits in a mouse model of anti-NMDAR encephalitis induced by active immunization.

Anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis is a neurological disorder, characterized by cognitive deficits as one of its vital features. The nucleotide-binding oligomerization domain-like receptor (NLRP3) inflammasome is a key contributor to neuroinflammation and cognitive deficits in neurological diseases. However, the underlying mechanism of anti-NMDAR encephalitis remains unclear, and the biological function of the NLRP3 inflammasome in this condition has not been elucidated. In this study, a mouse model of anti-NMDAR encephalitis was induced by active immunization with the GluN1356-385 peptide (NEA model). The NLRP3 inflammasome in the hippocampus and temporal cortex was investigated using real-time quantitative PCR (RT-qPCR), western blotting, and immunofluorescence staining. The impact of MCC950 on cognitive function and NLRP3 inflammation was assessed. Confocal immunofluorescence staining and Sholl analysis were employed to examine the function and morphology of microglia. In the current study, we discovered overactivation of the NLRP3 inflammasome and an enhanced inflammatory response in the NEA model, particularly in the hippocampus and temporal cortex. Furthermore, significant cognitive dysfunction was observed in the NEA model. While, MCC950, a selective inhibitor of the NLRP3 inflammasome, sharply attenuated the inflammatory response in mice, leading to mitigated cognitive deficits of mice and more regular arrangements of neurons and reduced number of hyperchromatic cells were also observed in the hippocampus area. In addition, we found that the excess elevation of NLRP3 inflammasome was mainly expressed in microglia accompanied with the overactivation of microglia, while MCC950 treatment significantly inhibited the increased number and activated morphological changes of microglia in the NEA model. Altogether, our study reveals the vital role of overactivated NLRP3 signaling pathway in aggravating the inflammatory response and cognitive deficits and the potential protective effect of MCC950 in anti-NMDAR encephalitis. Thus, MCC950 represents a promising strategy for anti-inflammation in anti-NMDAR encephalitis and our study lays a theoretical foundation for it to become a clinically targeted drug.

Rapamycin alleviates mitochondrial dysfunction in anti-NMDAR encephalitis mice.

Anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis is one of the most prevalent forms of autoimmune encephalitis, characterized by a series of neurological and psychiatric symptoms, including cognitive impairment, seizures and psychosis. The underlying mechanism of anti-NMDAR encephalitis remains unclear. In the current study, the mouse model of anti-NMDAR encephalitis with active immunization was performed. We first uncovered excessive mitochondrial fission in the hippocampus and temporal cortex of anti-NMDAR encephalitis mice, indicated by elevated level of Phospho-DRP1 (Ser616) (p-Drp1-S616). Moreover, blockade of the autophagic flux was also demonstrated, leading to the accumulation of fragmented mitochondria, and elevated levels of mitochondrial reactive oxygen species (mtROS) and mitochondrial DNA (mtDNA) in anti-NMDAR encephalitis. More importantly, we found that the mTOR signaling pathway was overactivated, which could aggravate mitochondrial fission and inhibit autophagy, resulting in mitochondrial dysfunction. While rapamycin, the specific inhibitor of the mTOR signaling pathway, significantly alleviated mitochondrial dysfunction by inhibiting mitochondrial fission and enhancing autophagy. Levels of mtROS and mtDNA were markedly reduced after the treatment of rapamycin. In addition, rapamycin also significantly alleviated cognitive dysfunction and anxious behaviors found in anti-NMDAR encephalitis mice. Thus, our study reveals the vital role of mitochondrial dysfunction in pathological mechanism of anti-NMDAR encephalitis and lays a theoretical foundation for rapamycin to become a clinically targeted drug for anti-NMDAR encephalitis.

The miR-23b-3p from adipose-derived stem cell exosomes alleviate inflammation in mice experiencing kainic acid-induced epileptic seizures.

Epilepsy is a common neurologic disorder. While a good clinical solution is still missing, studies have confirmed that exosomes (Exos) derived from adipose-derived stem cells (ADSCs) had a therapeutic effect on various diseases, including neurological diseases. Therefore, this study aimed to reveal whether ADSC-Exo treatment could improve kainic acid (KA)-induced seizures in epileptic mice. ADSCs and Exos were isolated. Mice were generated with KA-induced epileptic seizures. ELISA was used to detect inflammatory factor expression. Luciferase reporter analysis detection showed a relationship among miR-23b-3p, STAT1, and glyoxylate reductase 1 (GlyR1). ADSC-Exos had a protective effect on KA-induced seizures by inhibiting inflammatory factor expression and the M1 microglia phenotype. The result showed that miR-23b-3p played an important role in the Exo-mediated protective effect in KA-induced seizures in epileptic mice by regulating STAT1 and GlyR1. Luciferase reporter analysis confirmed that miR-23b-3p interacted with the 3'-UTR of STAT1 and GlyR1. The miR-23b-3p inhibited M1 microglia-mediated inflammatory factor expression in microglial cells by regulating STAT1 and GlyR1. The downregulation of miR-23b-3p decreased the protective effect of ADSC-Exos on KA-induced seizures in epileptic mice. The miR-23b-3p from ADSC-Exos alleviated inflammation in mice with KA-induced epileptic seizures.

Clinical features of epileptic seizures in patients with mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes.

BACKGROUND AND PURPOSE: This study aimed to characterize the clinical features of epilepsy in mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS) and analyze the clinical determinants for drug-resistant epilepsy in MELAS. METHODS: A single-center, retrospective study was conducted to investigate the clinical features of epilepsy in patients with MELAS. Collected variables included seizure semiology, electroencephalography (EEG), muscle biopsy, genetic testing, neuroimaging findings, resting serum lactic value and modified Rankin scale (mRS) of patients with MELAS. We also investigated the differences between the adult-onset group and the child-onset group and analyzed the risk factors for drug-resistant epilepsy in MELAS. RESULTS: We studied 97 patients (56 males: 41 females) with confirmed MELAS. Epileptic seizure occurred in 100.0% of patients and the initial symptom of 69.1% patients was epileptic seizure. The average age of disease onset was 21.0 years, ranging from 2 to 60 years. The seizure types of these patients with MELAS were variable, with generalized onset (51.5%) to be the most common type. The EEG changes in the patients with MELAS were mainly slow wave (90.9%) and epileptiform discharge (68.2%). The child-onset group with earlier seizure onset presented significantly higher resting serum lactic value (p = 0.0048) and lower incidence of stroke-like lesion in the brain (p = 0.003), especially in the temporal lobe (p < 0.001), compared with the adult-onset group. Importantly, drug-resistant epilepsy in MELAS was demonstrated to be closely related to the earlier age of seizure onset (p = 0.013), as well as the higher mRS score (p < 0.001) and higher resting serum lactic value (p = 0.009). CONCLUSION: Early identification of MELAS should be considered among individuals with recurrent epilepsy through clinical screening. Age of seizure onset and resting serum lactic value may predict the development of drug-resistant epilepsy in MELAS. Close observation and appropriate anti-epileptic treatment are indispensable for individuals with MELAS to improve the prognosis. Further studies with larger sample size are required to further evaluate the risk factors of drug-resistant epilepsy in MELAS and provide guidance on treatment of MELAS.

Elevated cerebrospinal fluid YKL-40 levels in patients with anti-gamma-aminobutyric- acid-B receptor encephalitis.

OBJECTIVE: Anti-gamma-aminobutyric-acid-B receptor (GABAbR) encephalitis is a rare form of autoimmune encephalitis. Until now, there are few biomarkers that can indicate the severity and prognosis of patients with anti-GABAbR encephalitis. The objective of this study was to exam the changes of chitinase-3-like protein 1 (YKL-40) in patients with anti-GABAbR encephalitis. In addition, whether YKL-40 could indicate the disease severity was also evaluated. METHODS: The clinical features of 14 patients with anti-GABAbR encephalitis and 21 patients with anti-N-methyl-d-aspartate receptor (NMDAR) encephalitis were retrospectively studied. YKL-40 levels in serum and cerebral fluid (CSF) of patients were detected by enzyme-linked immunosorbent assay. The correlation of modified Rankin Scale (mRS) score of encephalitis patients and YKL40 levels were analyzed. RESULTS: YKL-40 levels in CSF were significantly higher in patients with anti-GABAbR encephalitis or anti-NMDAR encephalitis than those in controls. YKL-40 levels between these two encephalitis groups were not different. Moreover, YKL-40 levels in CSF from patients with anti-GABAbR encephalitis were positively correlated with the mRS score at admission and at 6-month follow-up. CONCLUSION: YKL-40 level is elevated in CSF from patients with anti-GABAbR encephalitis at early disease stage. YKL-40 may be a potential biomarker indicating the prognosis of patients with anti-GABAbR encephalitis.

Dual hypoxia-responsive supramolecular complex for cancer target therapy.

The prognosis with pancreatic cancer is among the poorest of any human cancer. One of the important factors is the tumor hypoxia. Targeting tumor hypoxia is considered a desirable therapeutic option. However, it has not been translated into clinical success in the treatment of pancreatic cancer. With enhanced cytotoxicities against hypoxic pancreatic cancer cells, BE-43547A2 (BE) may serve as a promising template for hypoxia target strategy. Here, based on rational modification, a BE prodrug (NMP-BE) is encapsulated into sulfonated azocalix[5]arene (SAC5A) to generate a supramolecular dual hypoxia-responsive complex NMP-BE@SAC5A. Benefited from the selective load release within cancer cells, NMP-BE@SAC5A markedly suppresses tumor growth at low dose in pancreatic cancer cells xenograft murine model without developing systemic toxicity. This research presents a strategy for the modification of covalent compounds to achieve efficient delivery within tumors, a horizon for the realization of safe and reinforced hypoxia target therapy using a simple approach.

Alternating hemiplegia of childhood in chinese following long-term treatment with flunarizine or topiramate.

OBJECTIVE: Alternating hemiplegia of childhood (AHC) is a rare and intractable disorder. The etiology and standard therapy of AHC remain unknown. The long-term effects of flunarizine or topiramate on patients with AHC are still not clear. METHODS: Fifteen patients were investigated in this study. Their neurological disturbance and mental retardation after drug therapy were evaluated. RESULTS: Nine patients treated with flunarizine therapy and three children with topimarate treatment presented with shorter duration or less frequency of the hemiplegic attacks. These drug responsive patients also showed improvements on neurological disturbance including eye movement disorder, choreoathetotic movements, dystonia, and ataxia. However, seizure episodes and cognitive impairments were not alleviated in AHC with long-term drug therapy. CONCLUSIONS: The findings from the present study support flunarizine or topitamate as the rational treatment for AHC.

Risk factors for postictal generalized EEG suppression in generalized convulsive seizure: A systematic review and meta-analysis.

BACKGROUND AND PURPOSE: Postictal generalized EEG suppression (PGES) has been suggested as a pathophysiological hallmark for sudden unexpected death in epilepsy (SUDEP). We aimed to characterize the clinical determinants for PGES occurrence after generalized convulsive seizures (GCS). METHODS: We systematically searched Pubmed, Embase and Medline databases up to 30 August 2021. Eligibility screening, data extraction, and quality assessment of the retrieved articles were conducted by two independent reviewers. Studies reporting potential risk factors of PGES occurrence in GCS were included for subsequent meta-analysis and PGES was defined as a generalized EEG attenuation of any duration >1s below 10µV, immediately or within 30s after an ictal EEG pattern has terminated. A fixed-effects model was applied when the heterogeneity is low (I2 values < 50%). Otherwise, a random-effects model was used (I2 values ≥ 50%). We assessed the odds ratio (OR) as outcome measure for dichotomous variables and the STD Mean Difference (SMD) for continuous variables. The Begg test and the Egger test was applied in the assessment of publication bias. RESULTS: A total of 15 relevant studies were identified, enrolling 2057 GCSs. The incidence of PGES in GCS from 15 studies varied from 23% to 86%. The longer tonic phase duration (SMD, 0.26; 95%CI, 0.13 to 0.39; p < 0.001), sleep state at GCS onset (OR,1.63; 95%CI, 1.24 to 2.16; p = 0.001), older age of epilepsy onset (SMD, 0.48; 95%CI, 0.21 to 0.75; p = 0.001), the presence of postictal immobility (OR, 78.05; 95%CI, 32.31 to 188.53; p < 0.001) and oxygen desaturation nadir (SMD, -0.54; 95%CI, -0.76 to -0.33; p < 0.001) showed significant association with the likelihood of having PGES in GCS, but not total seizure duration (SMD, -0.06; 95%CI, -0.20 to 0.08; p = 0.385), tonic-clonic duration (SMD, -0.12; 95%CI, -0.26 to 0.01; p = 0.071), clonic phase duration (SMD, -0.09; 95%CI, -0.27 to 0.08; p = 0.293), epilepsy duration of patients (SMD, -0.09; 95%CI, -0.27 to 0.08; p = 0.293) or lack of early O2 administration (OR, 1.59; 95%CI, 0.80 to 3.17; p = 0.184). CONCLUSION: The current study informed that PGES is common after GCS. Early identification should be considered among individuals with GCS at high risk of PGES through clinical screening. Further studies with larger sample size are required for individualized evaluation of the risk of PGES in GCS and more effort is needed to further evaluate the risk of SUDEP.