Incidence of Seizures in Stroke Patients

INTRODUCTION: Stroke is one of the most common causes of seizures in elderly. The relation between seizures and stroke was recognized more than a century ago by John Hughling Jackson. The reported incidence of seizures after stroke varies from 4.1% - 12.5%. This is related to different study population and follow up times. The incidence of post stroke seizures in India is 13%. Despite the relatively low incidence of seizures after cerebral stroke, Post stroke seizures is one of the most common causes of seizures due to the high incidence of stroke. A seizure may occur before, at the onset of, or weeks to months after a stroke. Hence the onset of seizures in adult or elderly population may be a warning sign for further stroke and warrants a study of patients cerebral circulation. An important risk factor for development of seizures after stroke is the involvement of cerebral cortex. Hemorrhagic strokes result in seizures more frequently than do Ischemic strokes. The presence of precipitating factors like hyperglycemia, hypoglycemia, hypernatremia, hypocalcaemia, hypomagnesaemia, renal failure and infections – increase the chance of seizures. Atrial fibrillation and diabetes are found to be associated with increased risk of early seizures. There is a strong link between stroke severity and risk of seizures after stroke. The risk is very low in mild strokes. AIM: Both early and late onset post stroke seizures left sided cortical infarcts, increased stroke severity and recurrent strokes are the risk factors for post stroke late epilepsy. The present study was conducted prospectively to define the clinical features, CT findings and EEG correlation of stroke patients with seizures. MATERIALS AND METHODS: This study was carried out in the Department of General medicine and the Department of Neuromedicine at the Govt. Stanley Hospital, Chennai, India from August 2005 to Jan 2006. The patients in the age group of 30 to 88 yrs with the following criteria were included in the study. Inclusion Criteria: 1. Diagnosis of stroke, 2. With or without seizures. Exclusion Criteria: 1. Previous seizures, 2. Previous brain surgery, 3. Head trauma, 4. Sub arachnoid hemorrhage, 5. Aneurysm, tumor, 6. AVM related bleed, 7. Significant metabolic abnormality, 8. Septicemia. All patients were interviewed using a structured proforma. This includes a detailed history regarding stroke, type of stroke, time and nature of onset, associated with seizures, level of consciousness etc. A detailed past history regarding SHT, DM, RHD were recorded. A detailed clinical examination was performed. The biochemical investigations done in these patients include blood sugar, urea, creatinine, serum electrolytes and LFT. Chest X ray and ECG were taken for all patients. Computerized tomography scan of brain was done to all patients with special emphasize to look for infarct, hemorrhage and the site of lesion. EEG was taken for nearly 50% of patients who presented without seizures and eight out of nine patients who presented with seizures. RESULTS: A total of eighty-one patients who satisfied the inclusion criteria between the ages of 30 and 88 years were included in the study. 17 (21%) of the eighty-one patients were females and 64 (79%) were males. The patients were grouped based on the CT scan findings. There were sixty patients (74%) in group I, seven (8.6%) in group II and fourteen (17.3%) patients in group III. Analysis of Stroke Patients with Seizures: Nine patients (6 males and 3 females) in age range of 47 yrs to 75 yrs (mean age 61 yrs) from 81 patients of stroke who fulfilled the selection criteria had seizures. The incidence of seizures is 11.1%. 5 (55.6%) of the 9 patients who had seizures had infarct in brain, 3(33.3%) patients had hemorrhage in the brain and 1(11.1%) patient showed normal study in CT scan. None of the 5 patients who showed infarct in CT scan brain had an evidence for embolic stroke (vascular disease, atrial fibrillation and myocardial infarction). Of the nine patients who had seizures 5 patients showed left sided cortical involvement 3 pts showed right-sided cortical involvement one showed bilateral cortical involvement. All the 5 patients who had an infarct in the brain showed involvement of cortical areas with or without sub cortical region involvement, but no patient showed pure sub cortical lesion on cranial CT. 2 of the hematoma were in the cerebral cortex and 1 was primarly in the capsulo ganglionic region. None of the hematoma showed an evidence of intraventricular extension. 6 patients (67%) had early immediate seizures (i.e. within 24 hrs of onset of stroke and 3 (33%) had late onset seizures. In patients with early immediate seizures 2(33%) of them presented with focal seizures, 2(33%) presented with GTCS, 1 with focal becoming secondary generalized (17%) and one (17%) patient presented with status epilepticus. Of the 3 patients who presented with late onset seizures 2(67%) had GTCS and 1(33%) had focal seizure, none of 3 patients had history of recurrent seizures. EEG recordings were normal in 6 of them, 2 of them showed diffuse slowing, and in one patient EEG cannot be recorded. None of the patients showed focal slowing or epileptiform discharges. No specific EEG pattern was seen with early versus late seizures. CONCLUSION: 1. Post stroke early onset seizures occur within two weeks of stroke onset, while late onset seizures occur after two weeks. 2. The incidence of seizures in this study is 11.1% 3. The incidence of early onset seizures is 7.4% 4. The incidence of late onset seizures is 3.7% 5. The incidence of focal seizures in early onset post stroke seizures is 33%. 6. The incidence of GTCS (including status epilepticus) in early onset post stroke seizures is 50%. 7. EEG recordings were normal in 78% of patients while 22% showed diffuse slowing. 8. The involvement of cerebral cortex has been emphasized in the pathogenesis of epilepsy caused by stroke. In the present study 100% of infarctions leading to seizure involved cerebral cortex with or without involvement of subcortical region. 9. 67% of hematomas were localized exclusively to the cortical region. 10. 55% of patients showed left side cortical involvement while 33.3% showed right side cortical involvement, and 11.1% showed bilateral involvement

The cytokine temporal profile in rat cortex after controlled cortical impact

Cerebral inflammatory responses may initiate secondary cascades following traumatic brain injury (TBI). Changes in the expression of both cytokines and chemokines may activate, regulate, and recruit innate and adaptive immune cells associated with secondary degeneration, as well as alter a host of other cellular processes. In this study, we quantified the temporal expression of a large set of inflammatory mediators in rat cortical tissue after brain injury. Following a controlled cortical impact (CCI) on young adult male rats, cortical and hippocampal tissue of the injured hemisphere and matching contralateral material was harvested at early (4, 12, and 24 hours) and extended (3 and 7 days) time points post-procedure. Naïve rats that received only anesthesia were used as controls. Processed brain homogenates were assayed for chemokine and cytokine levels utilizing an electrochemiluminescence-based multiplex ELISA platform. The temporal profile of cortical tissue samples revealed a multi-phasic injury response following brain injury. CXCL1, IFN-γ, TNF-α levels significantly peaked at four hours post-injury compared to levels found in naïve or contralateral tissue. CXCL1, IFN-γ, and TNF-α levels were then observed to decrease at least 3-fold by 12 hours post-injury. IL-1β, IL-4, and IL-13 levels were also significantly elevated at four hours post-injury although their expression did not decrease more than 3-fold for up to 24 hours post-injury. Additionally, IL-1β and IL-4 levels displayed a biphasic temporal profile in response to injury, which may suggest their involvement in adaptive immune responses. Interestingly, peak levels of CCL2 and CCL20 were not observed until after four hours post-injury. CCL2 levels in injured cortical tissue were significantly higher than peak levels of any other inflammatory mediator measured, thus suggesting a possible use as a biomarker. Fully elucidating chemokine and cytokine signaling properties after brain injury may provide increased insight into a number of secondary cascade events that are initiated or regulated by inflammatory responses

NCI60 Cancer Cell Line Panel Data and RNAi Analysis Help Identify EAF2 as a Modulator of Simvastatin and Lovastatin Response in HCT-116 Cells

Simvastatin and lovastatin are statins traditionally used for lowering serum cholesterol levels. However, there exists evidence indicating their potential chemotherapeutic characteristics in cancer. In this study, we used bioinformatic analysis of publicly available data in order to systematically identify the genes involved in resistance to cytotoxic effects of these two drugs in the NCI60 cell line panel. We used the pharmacological data available for all the NCI60 cell lines to classify simvastatin or lovastatin resistant and sensitive cell lines, respectively. Next, we performed whole-genome single marker case-control association tests for the lovastatin and simvastatin resistant and sensitive cells using their publicly available Affymetrix 125K SNP genomic data. The results were then evaluated using RNAi methodology. After correction of the p-values for multiple testing using False Discovery Rate, our results identified three genes (NRP1, COL13A1, MRPS31) and six genes (EAF2, ANK2, AKAP7, STEAP2, LPIN2, PARVB) associated with resistance to simvastatin and lovastatin, respectively. Functional validation using RNAi confirmed that silencing of EAF2 expression modulated the response of HCT-116 colon cancer cells to both statins. In summary, we have successfully utilized the publicly available data on the NCI60 cell lines to perform whole-genome association studies for simvastatin and lovastatin. Our results indicated genes involved in the cellular response to these statins and siRNA studies confirmed the role of the EAF2 in response to these drugs in HCT-116 colon cancer cells

Repair at Single Targeted DNA Double-Strand Breaks in Pluripotent and Differentiated Human Cells

Differences in ex vivo cell culture conditions can drastically affect stem cell physiology. We sought to establish an assay for measuring the effects of chemical, environmental, and genetic manipulations on the precision of repair at a single DNA double-strand break (DSB) in pluripotent and somatic human cells. DSBs in mammalian cells are primarily repaired by either homologous recombination (HR) or nonhomologous end-joining (NHEJ). For the most part, previous studies of DSB repair in human cells have utilized nonspecific clastogens like ionizing radiation, which are highly nonphysiologic, or assayed repair at randomly integrated reporters. Measuring repair after random integration is potentially confounded by locus-specific effects on the efficiency and precision of repair. We show that the frequency of HR at a single DSB differs up to 20-fold between otherwise isogenic human embryonic stem cells (hESCs) based on the site of the DSB within the genome. To overcome locus-specific effects on DSB repair, we used zinc finger nucleases to efficiently target a DSB repair reporter to a safe-harbor locus in hESCs and a panel of somatic human cell lines. We demonstrate that repair at a targeted DSB is highly precise in hESCs, compared to either the somatic human cells or murine embryonic stem cells. Differentiation of hESCs harboring the targeted reporter into astrocytes reduces both the efficiency and precision of repair. Thus, the phenotype of repair at a single DSB can differ based on either the site of damage within the genome or the stage of cellular differentiation. Our approach to single DSB analysis has broad utility for defining the effects of genetic and environmental modifications on repair precision in pluripotent cells and their differentiated progeny

Neurotrophic requirements of human motor neurons defined using amplified and purified stem-cell derived cultures

Neurotrophic requirements of human motor neurons defined using amplified and purified stem-cell derived culturesHuman motor neurons derived from embryonic and induced pluripotent stem cells (hESCs and hiPSCs) are a potentially important tool for studying motor neuron survival and pathological cell death. However, their basic survival requirements remain poorly characterized. Here, we sought to optimize a robust survival assay and characterize their response to different neurotrophic factors. First, to increase motor neuron yield, we screened a small-molecule collection and found that the Rho-associated kinase (ROCK) inhibitor Y-27632 enhances motor neuron progenitor proliferation up to 4-fold in hESC and hiPSC cultures. Next, we FACS-purified motor neurons expressing the Hb9::GFP reporter from Y-27632-amplified embryoid bodies and cultured them in the presence of mitotic inhibitors to eliminate dividing progenitors. Survival of these purified motor neurons in the absence of any other cell type was strongly dependent on neurotrophic support. GDNF, BDNF and CNTF all showed potent survival effects (EC(50) 1-2 pM). The number of surviving motor neurons was further enhanced in the presence of forskolin and IBMX, agents that increase endogenous cAMP levels. As a demonstration of the ability of the assay to detect novel neurotrophic agents, Y-27632 itself was found to support human motor neuron survival. Thus, purified human stem cell-derived motor neurons show survival requirements similar to those of primary rodent motor neurons and can be used for rigorous cell-based screening.This work was funded by Project A.L.S., P2ALS and NYSTEM grant number CO24415. The work of N.J.L. was supported by the Portuguese Foundation for Science and Technology SFRH/BD/33421/2008 and the Luso-American Development Foundation. B.J.-K. was supported by the National Institute of Neurological Disorders and Stroke (NINDS). L.R. was supported by the Swedish Brain Foundation/Hjarnfonden. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript

Anti-cancer potential of MAPK pathway inhibition in paragangliomas-effect of different statins on mouse pheochromocytoma cells.

To date, malignant pheochromocytomas and paragangliomas (PHEOs/PGLs) cannot be effectively cured and thus novel treatment strategies are urgently needed. Lovastatin has been shown to effectively induce apoptosis in mouse PHEO cells (MPC) and the more aggressive mouse tumor tissue-derived cells (MTT), which was accompanied by decreased phosphorylation of mitogen-activated kinase (MAPK) pathway players. The MAPK pathway plays a role in numerous aggressive tumors and has been associated with a subgroup of PHEOs/PGLs, including K-RAS-, RET-, and NF1-mutated tumors. Our aim was to establish whether MAPK signaling may also play a role in aggressive, succinate dehydrogenase (SDH) B mutation-derived PHEOs/PGLs. Expression profiling and western blot analysis indicated that specific aspects of MAPK-signaling are active in SDHB PHEOs/PGLs, suggesting that inhibition by statin treatment could be beneficial. Moreover, we aimed to assess whether the anti-proliferative effect of lovastatin on MPC and MTT differed from that exerted by fluvastatin, simvastatin, atorvastatin, pravastatin, or rosuvastatin. Simvastatin and fluvastatin decreased cell proliferation most effectively and the more aggressive MTT cells appeared more sensitive in this respect. Inhibition of MAPK1 and 3 phosphorylation following treatment with fluvastatin, simvastatin, and lovastatin was confirmed by western blot. Increased levels of CASP-3 and PARP cleavage confirmed induction of apoptosis following the treatment. At a concentration low enough not to affect cell proliferation, spontaneous migration of MPC and MTT was significantly inhibited within 24 hours of treatment. In conclusion, lipophilic statins may present a promising therapeutic option for treatment of aggressive human paragangliomas by inducing apoptosis and inhibiting tumor spread

Association of Variants in the SPTLC1 Gene With Juvenile Amyotrophic Lateral Sclerosis

Importance: Juvenile amyotrophic lateral sclerosis (ALS) is a rare form of ALS characterized by age of symptom onset less than 25 years and a variable presentation.Objective: To identify the genetic variants associated with juvenile ALS.Design, Setting, and Participants: In this multicenter family-based genetic study, trio whole-exome sequencing was performed to identify the disease-associated gene in a case series of unrelated patients diagnosed with juvenile ALS and severe growth retardation. The patients and their family members were enrolled at academic hospitals and a government research facility between March 1, 2016, and March 13, 2020, and were observed until October 1, 2020. Whole-exome sequencing was also performed in a series of patients with juvenile ALS. A total of 66 patients with juvenile ALS and 6258 adult patients with ALS participated in the study. Patients were selected for the study based on their diagnosis, and all eligible participants were enrolled in the study. None of the participants had a family history of neurological disorders, suggesting de novo variants as the underlying genetic mechanism.Main Outcomes and Measures: De novo variants present only in the index case and not in unaffected family members.Results: Trio whole-exome sequencing was performed in 3 patients diagnosed with juvenile ALS and their parents. An additional 63 patients with juvenile ALS and 6258 adult patients with ALS were subsequently screened for variants in the SPTLC1 gene. De novo variants in SPTLC1 (p.Ala20Ser in 2 patients and p.Ser331Tyr in 1 patient) were identified in 3 unrelated patients diagnosed with juvenile ALS and failure to thrive. A fourth variant (p.Leu39del) was identified in a patient with juvenile ALS where parental DNA was unavailable. Variants in this gene have been previously shown to be associated with autosomal-dominant hereditary sensory autonomic neuropathy, type 1A, by disrupting an essential enzyme complex in the sphingolipid synthesis pathway.Conclusions and Relevance: These data broaden the phenotype associated with SPTLC1 and suggest that patients presenting with juvenile ALS should be screened for variants in this gene.</p