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SUMMARY: Stroke is the leading cause of acquired physical disability in adults and second leading cause of mortality throughout the world. Treatment strategies to curb the effects of stroke would be of great benefit. Pongamia pinnata is a recent attraction in medicine, owing to its abundant medicinal benefits with minimal side effects. The present study aimed to examine acute and subacute effect of Pongamia pinnata leaf extract on transient cerebral hypoperfusion and reperfusion (tCHR) in Wistar rats. 24 adult Wistar rats (12 each for acute and subacute study) were divided in to four groups each viz normal control group, tCHR + NS group, tCHR + 200mg/kg bw and tCHR + 400mg/kg bw groups. Cerebral ischemia induction was carried out by bilateral common carotid artery occlusion and reperfusion. Ethanolic extract of Pongamia pinnata leaves were orally administered for 7 days and 21 days after the surgical procedure for acute and subacute study respectively. Behavioural analysis, histological assessment, and estimation of mRNA levels of HIF-1, GDNF, BDNF and NF-kB were performed. In both acute and subacute study, there was significant improvement in the beam walking assay, neuronal count, decreased neuronal damage in histological sections and higher mRNA expression of BDNF and GDNF in the treatment groups. There was no significant difference in the expression of HIF1 and NF-kB. Thus, Pongamia pinnata has excellent neurorestorative property reversing many of the effects of ischemic stroke induced by tCHR in rats with the underlying mechanism being an improvement in the expression of neurotrophic factors GDNF and BDNF.

El ataque cerebrovascular es la principal causa de discapacidad física adquirida en adultos y la segunda causa de mortalidad en todo el mundo. Las estrategias de tratamiento para frenar los efectos del ataque cerebrovascular serían de gran beneficio. Pongamia pinnata es una atracción reciente en la medicina, debido a sus abundantes beneficios medicinales con mínimos efectos secundarios. El presente estudio tuvo como objetivo examinar el efecto agudo y subagudo del extracto de hoja de Pongamia pinnata sobre la hipoperfusión y reperfusión cerebral transitoria (tCHR) en ratas Wistar. Se dividieron 24 ratas Wistar adultas (12 cada una para el estudio agudo y subagudo) en cuatro grupos, el grupo control normal, el grupo tCHR + NS, los grupos tCHR + 200 mg/kg de peso corporal y tCHR + 400 mg/kg de peso corporal. La inducción de la isquemia cerebral se llevó a cabo mediante oclusión y reperfusión bilateral de la arteria carótida común. El extracto etanólico de hojas de Pongamia pinnata se administró por vía oral durante 7 días y 21 días después del procedimiento quirúrgico para estudio agudo y subagudo respectivamente. Se realizaron análisis de comportamiento, evaluación histológica y estimación de los niveles de ARNm de HIF-1, GDNF, BDNF y NF-kB. Tanto en el estudio agudo como en el subagudo, hubo una mejora significativa en el ensayo de desplazamiento del haz, el recuento neuronal, una disminución del daño neuronal en las secciones histológicas y una mayor expresión de ARNm de BDNF y GDNF en los grupos con tratamiento. No hubo diferencias significativas en la expresión de HIF1 y NF-kB. Por lo tanto, Pongamia pinnata tiene una excelente propiedad neurorestauradora que revierte muchos de los efectos del ataque cerebrovascular isquémico inducido por tCHR en ratas, siendo el mecanismo subyacente una mejora en la expresión de los factores neurotróficos GDNF y BDNF.

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SUMMARY: Hypoxic preconditioning is known to induce neuroprotection, but its effects and pathways in chronic brain pathology still unknown. The aim was to establish an involvement of a7 subunit of nicotinic acetylcholine receptors (a7nAchRs), and sirtuins of 1 (SIRT1) and 3 (SIRT3) types in the effects of hypoxic hypobaric preconditioning on brain damage in mice with chronic cerebral hypoperfusion caused by the left common carotid artery occlusion. The male C57/6j (C57, wild type) and a7nAchRs(-/-) mice were divided to six experimental groups (10 mice per group): sham-operated C57, C57 with chronic cerebral hypoperfusion, C57 with hypoxic hypobaric preconditioning and chronic cerebral hypoperfusion, sham-operated a7nAchRs(-/-) mice, a7nAchRs(-/-) with chronic cerebral hypoperfusion, a7nAchRs(-/-) with hypoxic hypobaric preconditioning and chronic cerebral hypoperfusion. For preconditioning, mice were exposed to hypoxia by "lifting" in barochamber to simulated altitude of 5600 m a.s.l. for 1 h/day on 3 consecutive days before surgical manipulation. Expressions of SIRT1, SIRT3 in brain tissue, and histopathological changes of the hippocampi were examined. It was shown that 8-week chronic hypoperfusion of the brain, caused by unilateral occlusion of the common carotid artery, was accompanied by injury to the neurons of the hippocampi of both hemispheres, which was more pronounced on the side of the occlusion. This damage, as well as the mechanisms of neuroprotection induced by hypoxic preconditioning, were maintained for at least 8 weeks by mechanisms mediated through a7nAChRs. Deficite of a7nAChRs was accompanied with reduction of neuronal damage caused CCH in 8 weeks, as well as preconditioning effects, and lead to compensatory activation of regulatory and protective mechanisms mediated by SIRT1, in normal conditions and in CCH. In wild-type (C57) mice, protective mechanisms in CCH were realized to a greater extent by increased expression of SIRT3 in both hemispheres of the brain.

Se sabe que el precondicionamiento hipóxico induce neuroprotección, pero aún se desconocen sus efectos y vías en la patología cerebral crónica. El objetivo fue establecer la participación de la subunidad a7 de los receptores nicotínicos de acetilcolina (a7nAchR) y las sirtuinas de tipo 1 (SIRT1) y 3 (SIRT3) en los efectos del precondicionamiento hipóxico hipobárico sobre el daño cerebral en ratones con hipoperfusión cerebral crónica causada por la oclusión de la arteria carótida común izquierda. Los ratones macho C57/6j (C57, tipo salvaje) y a7nAchRs(-/-) se dividieron en seis grupos experimentales (10 ratones por grupo): C57 con operación simulada, C57 con hipoperfusión cerebral crónica, C57 con precondicionamiento hipobárico hipóxico y crónica. hipoperfusión cerebral, ratones a7nAchRs(-/-) operados de forma simulada, a7nAchRs(-/-) con hipoperfusión cerebral crónica, a7nAchRs(-/-) con precondicionamiento hipobárico hipóxico e hipoperfusión cerebral crónica. Para el preacondicionamiento, los ratones fueron expuestos a hipoxia "levantándolos" en una cámara de barro a una altitud simulada de 5600 m s.n.m. durante 1 h/día durante 3 días consecutivos antes de la manipulación quirúrgica. Se examinaron las expresiones de SIRT1, SIRT3 en tejido cerebral y los cambios histopatológicos de los hipocampos. Se demostró que la hipoperfusión cerebral crónica de 8 semanas, causada por la oclusión unilateral de la arteria carótida común, se acompañaba de lesión de las neuronas del hipocampo de ambos hemisferios y que era más pronunciada en el lado de la oclusión. Este daño, así como los mecanismos de neuroprotección inducidos por el precondicionamiento hipóxico, se mantuvieron durante al menos 8 semanas mediante mecanismos mediados por a7nAChR. El déficit de a7nAChR se acompañó de una reducción del daño neuronal causado por CCH en 8 semanas, así como de efectos de precondicionamiento, y condujo a una activación compensatoria de mecanismos reguladores y protectores mediados por SIRT1, en condiciones normales y en CCH. En ratones de tipo salvaje (C57), los mecanismos de protección en CCH se realizaron en mayor medida mediante una mayor expresión de SIRT3 en ambos hemisfe- rios del cerebro.

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Interactions between brain-resident and peripheral infiltrated immune cells are thought to contribute to neuroplasticity after cerebral ischemia. However, conventional bulk sequencing makes it challenging to depict this complex immune network. Using single-cell RNA sequencing, we mapped compositional and transcriptional features of peri-infarct immune cells. Microglia were the predominant cell type in the peri-infarct region, displaying a more diverse activation pattern than the typical pro- and anti-inflammatory state, with axon tract-associated microglia (ATMs) being associated with neuronal regeneration. Trajectory inference suggested that infiltrated monocyte-derived macrophages (MDMs) exhibited a gradual fate trajectory transition to activated MDMs. Inter-cellular crosstalk between MDMs and microglia orchestrated anti-inflammatory and repair-promoting microglia phenotypes and promoted post-stroke neurogenesis, with SOX2 and related Akt/CREB signaling as the underlying mechanisms. This description of the brain's immune landscape and its relationship with neurogenesis provides new insight into promoting neural repair by regulating neuroinflammatory responses.

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Purpose: Blackberries are rich in polyphenols and are a human health food continuously consumed to improve health and reduce diseases caused by aging. Herein, we evaluated the effects of daily blackberry administration before and after transient cerebral ischemia in gerbils. Methods: Blackberry extract (BBE) was orally administered twice a day for two weeks to protect against ischemic events during continuous administration. On the seventh day after administration, the bilateral common carotid arteries were transiently occluded for 5 min. To verify its therapeutic effect, BBE was administered after ischemia using a similar protocol without pre-administration. In both experiments, the number of viable neurons in the CA1 region of the hippocampus was assessed seven days after ischemic treatment. Results: The number of neurons in the group treated with BBE before ischemia was higher than that in the group treated with distilled water (p = 0.0601), and similar to that in the control group. In the BBE administration experiments after ischemia, the number of neurons was significantly reduced compared to that in the control group (p < 0.0001). Conclusions: Continuous BBE intake is expected to prevent or ameliorate ischemic events such as transient cerebral ischemia.

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La Enfermedad Cerebrovascular Isquémica (ECV-Isquémica) provoca alteraciones neurológicas agudas, causadas por la dis-función del flujo sanguíneo cerebral, lo que determina la pre-sencia de injuria neuronal.1Los factores de riesgo se clasifican en modificables y no modi-ficables entre estos últimos, los más frecuentes son: la hiperten-sión arterial, diabetes mellitus, obesidad, tabaco y sedentarismo, y su frecuencia es notablemente mayor después de los 65 años de edad (Anexo 1).1La Enfermedad Cerebrovascular Isquémica se caracteriza por ser la segunda causa de mortalidad a nivel mundial, y la ter-cera en causar discapacidad. En 2019, según el reporte del Ins-tituto Nacional de Estadísticas y Censos (INEC), se registraron 4577 fallecimientos producto de esta patología; y se reportó como la tercera causa de fallecimiento en hombres y mujeres en Ecuador.2El impacto económico que genera la ECV-Isquémica es con-siderable, puesto que se ha evidenciado que aproximadamente supone un gasto promedio de 4330 dólares en los primeros 3 meses posterior a presentar esta patología, sin considerar otras consecuencias como la pérdida laboral.3

Ischemic Cerebrovascular Disease (Ischemic-CVD) causes acute neurological alterations, caused by cerebral blood flow dysfunction, which determines the presence of neuronal injury.1Risk factors are classified as modifiable and non-modifiable, among the latter, the most frequent are: arterial hypertension, diabetes mellitus, obesity, smoking and sedentary lifestyle, and their frequency is notably higher after 65 years of age (Anexo 1).1Ischemic Cerebrovascular Disease is characterized as the second leading cause of mortality worldwide, and the third leading cause of disability. In 2019, according to the report of the National Ins-titute of Statistics and Census (INEC), 4577 deaths were regis-tered as a result of this pathology; and it was reported as the third leading cause of death in men and women in Ecuador.2The economic impact of CVD-ischemic stroke is considerable, since it has been shown that approximately US$ 4330 is spent on average in the first 3 months after the onset of this pathology, without considering other consequences such as loss of work.3

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Abstract Background The precise underlying mechanism of antioxidant effects of dexmedetomidine-induced neuroprotection against cerebral ischemia has not yet been fully elucidated. Activation of Nuclear factor erythroid 2-related factor (Nrf2) and Heme Oxygenase-1 (HO-1) represents a major antioxidant-defense mechanism. Therefore, we determined whether dexmedetomidine increases Nrf2/HO-1 expression after global transient cerebral ischemia and assessed the involvement of Protein Kinase C (PKC) in the dexmedetomidine-related antioxidant mechanism. Methods Thirty-eight rats were randomly assigned to five groups: sham (n = 6), ischemic (n = 8), chelerythrine (a PKC inhibitor; 5 mg.kg-1 IV administered 30 min before cerebral ischemia) (n = 8), dexmedetomidine (100 µg.kg-1 IP administered 30 min before cerebral ischemia (n = 8), and dexmedetomidine + chelerythrine (n = 8). Global transient cerebral ischemia (10 min) was applied in all groups, except the sham group; histopathologic changes and levels of nuclear Nrf2 and cytoplasmic HO-1 were examined 24 hours after ischemia insult. Results We found fewer necrotic and apoptotic cells in the dexmedetomidine group relative to the ischemic group (p< 0.01) and significantly higher Nrf2 and HO-1 levels in the dexmedetomidine group than in the ischemic group (p< 0.01). Additionally, chelerythrine co-administration with dexmedetomidine attenuated the dexmedetomidine-induced increases in Nrf2 and HO-1 levels (p< 0.05 and p< 0.01, respectively) and diminished its beneficial neuroprotective effects. Conclusion Preischemic dexmedetomidine administration elicited neuroprotection against global transient cerebral ischemia in rats by increasing Nrf2/HO-1 expression partly via PKC signaling, suggesting that this is the antioxidant mechanism underlying dexmedetomidine-mediated neuroprotection.

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RESUMEN INTRODUCCIÓN: La COVID-19 se acompaña de eventos tromboembólicos venosos y arteriales en pacientes con historia de hipertensión y aterosclerosis. Se reporta el caso de una paciente joven y sin factores de riesgo cardiovascular que adquirió la infección por el SARS-COV2 y luego presentó un accidente cerebrovascular isquémico. CASO: Paciente de 44 años hospitalizada por la covid-19 en tratamiento protocolario con anticoagulación, esteroide y oxígeno suplementario. Al día 7 del inicio de los síntomas respiratorios presentó infarto cerebral por trombosis de arteria carótida derecha, arteria cerebral media derecha e izquierda y edema cerebral hemisférico derecho, tras lo cual fue diagnosticada con muerte encefálica. El estudio vascular no documentó una etiología diferente a la covid-19. DISCUSIÓN: Se plantea que la infección condiciona un estado inflamatorio sistémico, endotelialitis, ulceración de placas ateroscleróticas preexistentes e hipercoagulabilidad. Lo anterior facilita la aparición de trombosis vascular. Es frecuente encontrar elevación de reactantes de fase aguda y de los productos del metabolismo de la fibrina. El accidente cerebrovascular (ACV) isquémico se ha descrito en el 1 al 5 % de los pacientes con la covid-19. En pacientes con factores de riesgo cardiovascular, durante las primeras 2 semanas desde el inicio de los síntomas respiratorios, el compromiso isquémico suele afectar a múltiples territorios vasculares. CONCLUSIÓN: La covid-19 por sí sola es un factor de riesgo para trombosis arterial secundaria a la inflamación sistémica y estados de hipercoagulabilidad, por lo que debe ser tenida en cuenta en el estudio de ACV isquémico en pacientes jóvenes.

ABSTRACT INTRODUCTION: It is known that COVID-19 is associated with venous and arterial thromboembolic events in patients with history of hypertension and atherosclerosis. Herein, it is presented a case of a young woman without known cardiovascular risk, who was infected by SARS-COV 2 and then an ischemic stroke. CASE: 44 years-old woman with moderate COVID-19 in protocolary treatment with anticoagulants, steroid and oxygen. In the seventh day since symptoms onset, she presented acute ischemic stroke due to acute thrombosis of right carotid artery, and right and left medial cerebral arteries, then rapidly developed malignant cerebral edema and brain death. Vascular study failed to report and etiology other than COVID-19. DISCUSSION: It is suggested that the infection produces a systemic inflammatory state, endothelialitis, ulceration of preexisting atherosclerotic plaques, and hypercoagulability that facilitate thrombosis. Ischemic stroke is described in 1 to 5% of COVID-19, it is common to find an elevation of acute phase reactants and products of fibrin metabolism. Multiple vascular territories are usually compromised in patients with known cardiovascular risk factors and 12 days after the onset of symptoms. CONCLUSION: COVID-19 by itself is a risk factor for arterial thrombosis secondary to systemic infection and hypercoagulability states and it should be taken into account in the study of ischemic stroke in young patients.

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La ocurrencia de complicaciones afecta la evolución y ensombrece el pronóstico de los pacientes con hemorragia subaracnoidea espontánea. El estudio tuvo como objetivo determinar la incidencia de complicaciones neurológicas y no neurológicas en una serie de pacientes con hemorragia subaracnoidea espontánea. Se realizó un estudio observacional, descriptivo-correlacional y retrospectivo, que abarcó 96 pacientes con hemorragia subaracnoidea espontánea entre 2016 y 2021. Se determinó la frecuencia de distintas complicaciones neurológicas y no neurológicas, así como la relación entre la presencia de complicaciones neurológicas y otras variables mediante análisis bivariado (Odds Ratio y su intervalo de confianza). Entre los resultados se destacan que el 53% de los pacientes presentó algún tipo de complicación neurológica, lo cual predominó en los de 60 años o más (62% vs 45%), en la etiología aneurismática (54% vs 27%) y cuando el diagnóstico fue realizado en las primeras 48 horas de iniciados los síntomas (56% vs 43%). La frecuencia de pacientes complicados aumentó desde el grado I hasta el grado V de la escala de Hunt y Hess (OR 30,6[8,2;113]), al igual que en la escala de Fisher (OR 11,6[3,1;43,2]). La complicación neurológica más frecuente fue la hipertensión endocraneana (39%), mientras que la no neurológica fue la neumonía (24%). Se concluye que la serie de pacientes estuvo caracterizada por una elevada frecuencia de complicaciones neurológicas, entre las que predominó la hipertensión endocraneana. Se demostró evidente relación entre los peores grados de las escalas de Hunt y Hess e imagenológica de Fisher, obtenidos en la valoración del paciente al ingreso, y la mayor incidencia de complicaciones neurológicas.

The occurrence of complications affects the evolution and darkens the prognosis of patients with spontaneous subarachnoid hemorrhage. The objective was to determine the incidence of neurological and non-neurological complications in a series of patients with spontaneous subarachnoid hemorrhage. An observational, descriptive-correlational and retrospective study of 96 patients with spontaneous subarachnoid hemorrhage between 2016 and 2021 was carried out. The frequency of different neurological and non-neurological complications was determined, as well as the relationship between the presence of neurological complications and other variables through analysis. bivariate (Odds Ratio and its confidence interval). Among the results it is found that 53% of the patients presented some type of neurological complication, which prevailed in those 60 years of age or older (62% vs 45%), in aneurysmal etiology (54% vs 27%) and when the diagnosis was made. in the first 48 hours of the onset of symptoms (56% vs 43%). The frequency of complicated patients increased from grade I to grade V on the Hunt and Hess scale (OR 30.6[8.2;113]), the same as on the Fisher scale (OR 11.6[3 ,1;43,2]). The most frequent neurological complication was intracranial hypertension (39%), while the non-neurological one was pneumonia (24%). It is concluded that the series of patients was characterized by a high frequency of neurological complications, among which intracranial hypertension predominated. An evident relationship was demonstrated between the worst grades on the Hunt and Hess and Fisher imaging scales, obtained in the patient's assessment on admission, and the higher incidence of neurological complications.

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INTRODUCTION@#Normal stress myocardial perfusion imaging (MPI) carries a favourable prognosis. Conversely, elevated coronary artery calcium (CAC) is associated with increased major adverse cardiovascular events (MACE). There is limited information on the prognosis and management of patients with elevated CAC and normal MPI. We aimed to assess the outcomes of patients with elevated CAC and normal MPI in relation to post-MPI statin use.@*METHODS@#A retrospective review of normal MPI with CAC score >300 was performed between 1 March 2016 and 31 January 2017 in a Singapore tertiary hospital. Patients with known atherosclerotic cardiovascular disease or left ventricular ejection fraction <50% on MPI were excluded. Patient demographics, prescriptions and MACE (cardiac death, nonfatal myocardial infarction and/or ischaemic stroke) at 24 months after MPI were traced using electronic records. Binary logistic regression was used to evaluate for independent predictors of MACE.@*RESULTS@#We included 311 patients (median age 71 years, 56.3% male), of whom 65.0% were on moderate to high-intensity statins (MHIS) after MPI. MACE was significantly lower in the post-MPI MHIS group (3.5% vs. 9.2%, P = 0.035). On univariate binary logistic regression, post-MPI MHIS use was the only significant predictor for MACE (odds ratio [OR] 0.355 [95% confidence interval (CI) 0.131-0.962], P = 0.042), even after multivariate adjustment (adjusted OR 0.363, 95% confidence interval 0.134-0.984, P = 0.046).@*CONCLUSION@#Post-MPI MHIS use is associated with lower MACE and is an independent negative predictor for 24-month MACE among patients with normal MPI and CAC >300.

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OBJECTIVE@#To explore the effect of electroacupuncture (EA) intervention on the vasoconstriction of cerebral artery smooth muscle cells after cerebral infarction.@*METHODS@#Male Wistar rats were randomly divided into 3 groups by a random number table: the model group (n=24), the EA group (n=24), and the normal group (n=6). The model and the EA groups were divided into different time subgroups at 0.5, 1, 3, and 6 h after middle cerebral artery occlusion (MCAO), with 6 rats in each subgroup. MCAO model was established using intraluminal suture occlusion method. The EA group was given EA treatment at acupoint Shuigou (GV 26) instantly after MCAO for 20 min. The contents of cerebrovascular smooth muscle MLCK, the 3 subunits of myosin light chain phosphatase (MLCP) MYPT1, PP1c-δ and M20, as well as myosin-ATPase activity were detected using immunohistochemistry and Western blotting.@*RESULTS@#The overall expression level of the MYPT1 and PP1c-δ in the model group was significantly higher (P<0.01). After EA intervention, the 0.5 h group expression level was close to that of the normal group (P>0.05), and the other subgroups were still significantly higher than the normal group (P<0.01). After EA intervention, the expression level of each subgroup was significantly lower than the corresponding model group. There was a significant difference between the 0.5 and 1 h subgroups (P<0.01), while a difference was also observed between the 3 and 6 h subgroups (P<0.05). The dynamic change rule gradually increased with the prolongation of infarction time within 6 h after infarction.@*CONCLUSION@#EA intervention can inhibit contraction of cerebral vascular smooth muscle cells and regulate smooth muscle relaxation by regulating MLCK pathway.

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OBJECTIVE@#To study the protective effect of forsythiaside B (FB) against cerebral oxidative stress injury induced by cerebral ischemia/reperfusion (I/R) in mice and explore the underlying mechanism.@*METHODS@#Ninety C57BL/6 mice were randomized into sham-operated group, middle cerebral artery occlusion (MCAO) model group, and low-, medium and highdose (10, 20, and 40 mg/kg, respectively) FB groups. The expression levels of MDA, ROS, PCO, 8-OHdG, SOD, GSTα4, CAT and GPx in the brain tissue of the mice were detected using commercial kits, and those of AMPK, P-AMPK, DAF-16, FOXO3 and P-FOXO3 were detected with Western blotting. Compound C (CC), an AMPK inhibitor, was used to verify the role of the AMPK pathway in mediating the therapeutic effect of FB. In another 36 C57BL/6 mice randomized into 4 sham-operated group, MCAO model group, FB (40 mg/kg) treatment group, FB+CC (10 mg/kg) treatment group, TTC staining was used to examine the volume of cerebral infarcts, and the levels of ROS and SOD in the brain were detected; the changes in the protein expressions of AMPK, P-AMPK, DAF-16, FOXO3 and P-FOXO3 in the brain tissue were detected using Western blotting.@*RESULTS@#In mice with cerebral IR injury, treatment with FB significantly reduced the levels of ROS, MDA, PCO and 8-OHdG, increased the activities of antioxidant enzymes SOD, GSTα4, CAT and GPx, and enhanced phosphorylation of AMPK and FOXO3 and DAF-16 protein expression in the brain tissue (P < 0.01). Compared with FB treatment alone, the combined treatment with FB and CC significantly reduced phosphorylation of AMPK and FOXO3, lowered expression of DAF-16 and SOD activity, and increased cerebral infarction volume and ROS level in the brain tissue of the mice (P < 0.01).@*CONCLUSION@#FB inhibits oxidative stress injury caused by cerebral I/R in mice possibly by enhancing AMPK phosphorylation, promoting the downstream DAF-16 protein expression and FOXO3 phosphorylation, increasing the expression of antioxidant enzymes, and reducing ROS level in the brain tissue.

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OBJECTIVE@#To explore the relationship between serum lipoprotein-associated phospholipase A2 (Lp-PLA2) level and the risk of acute ischemic stroke (AIS) recurrence in hypertensive patients.@*METHODS@#This retrospective case-control study was conducted among 211 hypertensive patients with AIS treated in Foshan First People's Hospital, including 35 patients with recurrence of AIS during the 1-year follow-up as confirmed by head CT/MR. In the overall patients, 60 had grade 1 hypertension (including 5 recurrent cases), 76 had grade 2 hypertension (with 11 recurrent cases), and 75 had grade 3 hypertension (with 19 recurrent cases). Univariate analysis, multivariate logistic regression analysis, trend analysis, and smooth curve fitting analysis were performed to explore the correlation between serum Lp-PLA2 level within 24 h after admission and the risk of AIS recurrence. The predictive efficacy of serum Lp-PLA2 level for AIS recurrence in different hypertension grades was evaluated using ROC curve analysis.@*RESULTS@#Serum Lp-PLA2 level, age, NIHSS score at admission, mRS scores at 7 days, homocysteine level and smoking status differed significantly between patients with and without AIS recurrence (P < 0.05). After adjustment for confounding factors, multivariate regression analysis showed that the highest tertile of Lp-PLA2 level was associated with a 4.13-fold increase of AIS recurrence risk compared with the lowest tertile (OR=5.13, 95% CI: 1.35-19.40), and each 1 ng/mL increase of Lp-PLA2 level was associated with a 1% increase of AIS recurrence risk (OR= 1.01, 95% CI: 1.01-1.02). Serum Lp-PLA2 level was shown to positively correlate with AIS recurrence risk, and in patients with grade 3 hypertension, its areas under the ROC curve for predicting AIS recurrence was 0.869 with a specificity of 0.893 and a sensitivity of 0.737.@*CONCLUSION@#Serum Lp-PLA2 concentration is an independent risk factor and potentially an effective predictor for AIS recurrence in patients with grade 3 hypertension.

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OBJECTIVE@#To explore the mechanism that mediates the effect of soybean isoflavones (SI) against cerebral ischemia/reperfusion (I/R) injury in light of the regulation of regional cerebral blood flow (rCBF), ferroptosis, inflammatory response and blood-brain barrier (BBB) permeability.@*METHODS@#A total of 120 male SD rats were equally randomized into sham-operated group (Sham group), cerebral I/R injury group and SI pretreatment group (SI group). Focal cerebral I/R injury was induced in the latter two groups using a modified monofilament occlusion technique, and the intraoperative changes of real-time cerebral cortex blood flow were monitored using a laser Doppler flowmeter (LDF). The postoperative changes of cerebral pathological morphology and the ultrastructure of the neurons and the BBB were observed with optical and transmission electron microscopy. The neurological deficits of the rats was assessed, and the severities of cerebral infarction, brain edema and BBB disruption were quantified. The contents of Fe2+, GSH, MDA and MPO in the ischemic penumbra were determined with spectrophotometric tests. Serum levels of TNF-α and IL-1βwere analyzed using ELISA, and the expressions of GPX4, MMP-9 and occludin around the lesion were detected with Western blotting and immunohistochemistry.@*RESULTS@#The rCBF was sharply reduced in the rats in I/R group and SI group after successful insertion of the monofilament. Compared with those in Sham group, the rats in I/R group showed significantly increased neurological deficit scores, cerebral infarction volume, brain water content and Evans blue permeability (P < 0.01), decreased Fe2+ level, increased MDA level, decreased GSH content and GPX4 expression (P < 0.01), increased MPO content and serum levels of TNF-α and IL-1β (P < 0.01), increased MMP-9 expression and lowered occludin expression (P < 0.01). All these changes were significantly ameliorated in rats pretreated with IS prior to I/R injury (P < 0.05 or 0.01).@*CONCLUSION@#SI preconditioning reduces cerebral I/R injury in rats possibly by improving rCBF, inhibiting ferroptosis and inflammatory response and protecting the BBB.

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Objective To evaluate the effect of surgical reconstruction of extracranial vertebral artery and to summarize the experience. Methods The clinical data of 15 patients undergoing surgical reconstruction of extracranial vertebral artery from September 2018 to June 2022 were collected.The operation methods,operation duration,intraoperative blood loss,operation complications,and relief of symptoms were retrospectively analyzed. Results Eleven patients underwent vertebral artery (V1 segment) to common carotid artery transposition,two patients underwent endarterectomy of V1 segment,two patients underwent V3 segment to external carotid artery bypass or transposition.The operation duration,intraoperative blood loss,and blocking time of common carotid artery varied within 120-340 min,50-300 ml,and 12-25 min,with the medians of 240 min,100 ml,and 16 min,respectively.There was no cardiac accident,cerebral hyperperfusion syndrome,cerebral hemorrhage or lymphatic leakage during the perioperative period.One patient suffered from cerebral infarction and three patients suffered from incomplete Horner's syndrome after the operation.During the follow-up (4-45 months,median of 26 months),there was no anastomotic stenosis,new cerebral infarction or cerebral ischemia. Conclusion Surgical reconstruction of extracranial vertebral artery is safe and effective,and individualized reconstruction strategy should be adopted according to different conditions.

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This study aims to explore the effect of Xiaoxuming Decoction on synaptic plasticity in rats with acute cerebral ischemia-reperfusion. A rat model of cerebral ischemia-reperfusion injury was established by middle cerebral artery occlusion(MCAO). Rats were randomly assigned into a sham group, a MCAO group, and a Xiaoxuming Decoction(60 g·kg~(-1)·d~(-1)) group. The Longa score was rated to assess the neurological function of rats with cerebral ischemia for 1.5 h and reperfusion for 24 h. The 2,3,5-triphenyltetrazolium chloride(TTC) staining and hematoxylin-eosin(HE) staining were employed to observe the cerebral infarction and the pathological changes of brain tissue after cerebral ischemia, respectively. Transmission electron microscopy was employed to detect the structural changes of neurons and synapses in the ischemic penumbra, and immunofluorescence, Western blot to determine the expression of synaptophysin(SYN), neuronal nuclei(NEUN), and postsynaptic density 95(PSD95) in the ischemic penumbra. The experimental results showed that the modeling increased the Longa score and led to cerebral infarction after 24 h of ischemia-reperfusion. Compared with the model group, Xiaoxuming Decoction intervention significantly decreased the Longa score and reduced the formation of cerebral infarction area. The modeling led to the shrinking and vacuolar changes of nuclei in the brain tissue, disordered cell arrangement, and severe cortical ischemia-reperfusion injury, while the pathological damage in the Xiaoxuming Decoction group was mild. The modeling blurred the synaptic boundaries and broadened the synaptic gap, while such changes were recovered in the Xiaoxuming Decoction group. The modeling decreased the fluorescence intensity of NEUN and SYN, while the intensity in Xiaoxuming Decoction group was significantly higher than that in the model group. The expression of SYN and PSD95 in the ischemic penumbra was down-regulated in the model group, while such down-regulation can be alleviated by Xiaoxuming Decoction. In summary, Xiaoxuming Decoction may improve the synaptic plasticity of ischemic penumbra during acute cerebral ischemia-reperfusion by up-regulating the expression of SYN and PSD95.

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Ischemic stroke is a major public health problem worldwide. Although the circadian clock is involved in the process of ischemic stroke, the exact mechanism of the circadian clock in regulating angiogenesis after cerebral infarction remains unclear. In the present study, we determined that environmental circadian disruption (ECD) increased the stroke severity and impaired angiogenesis in the rat middle cerebral artery occlusion model, by measuring the infarct volume, neurological tests, and angiogenesis-related protein. We further report that Bmal1 plays an irreplaceable role in angiogenesis. Overexpression of Bmal1 promoted tube-forming, migration, and wound healing, and upregulated the vascular endothelial growth factor (VEGF) and Notch pathway protein levels. This promoting effect was reversed by the Notch pathway inhibitor DAPT, according to the results of angiogenesis capacity and VEGF pathway protein level. In conclusion, our study reveals the intervention of ECD in angiogenesis in ischemic stroke and further identifies the exact mechanism by which Bmal1 regulates angiogenesis through the VEGF-Notch1 pathway.

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Chronic cerebral hypoperfusion leads to white matter injury (WMI), which subsequently causes neurodegeneration and even cognitive impairment. However, due to the lack of treatment specifically for WMI, novel recognized and effective therapeutic strategies are urgently needed. In this study, we found that honokiol and magnolol, two compounds derived from Magnolia officinalis, significantly facilitated the differentiation of primary oligodendrocyte precursor cells (OPCs) into mature oligodendrocytes, with a more prominent effect of the former compound. Moreover, our results demonstrated that honokiol treatment improved myelin injury, induced mature oligodendrocyte protein expression, attenuated cognitive decline, promoted oligodendrocyte regeneration, and inhibited astrocytic activation in the bilateral carotid artery stenosis model. Mechanistically, honokiol increased the phosphorylation of serine/threonine kinase (Akt) and mammalian target of rapamycin (mTOR) by activating cannabinoid receptor 1 during OPC differentiation. Collectively, our study indicates that honokiol might serve as a potential treatment for WMI in chronic cerebral ischemia.

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OBJECTIVE@#To establish a machine learning model to predict the risk of early neurological deterioration (END) based on the clinical and laboratory data of patients with acute ischemic stroke (AIS) before intravenous thrombolysis.@*METHODS@#The clinical data of AIS patients who received intravenous thrombolytic with recombinant tissue plasminogen activator (rt-PA) at the Stroke Center of the First Hospital of Qinhuangdao City from January 2019 to July 2022 were retrospectively analyzed. Patients were divided into END group and non-END group according to whether END appeared after intravenous thrombolytic. Clinical data of patients at admission were collected, including demographic characteristics, clinical evaluation, comorbidification, drug use history, laboratory tests, etc. Univariate and multivariate Logistic regression analysis were performed to screen out the independent predictors of the END of AIS patients after intravenous thrombolytic. The study subjects were randomly divided into a training set and a test set in a 7 : 3 ratio. Four machine learning prediction models, including Logistic regression (LR), K-nearest neighbor (KNN), support vector machine (SVM) and random forest (RF), were established based on independent predictors. The receiver operator characteristic curve (ROC curve) was used to evaluate the predictive ability of each model in END.@*RESULTS@#A total of 704 patients were enrolled, of whom 99 were identified as END and 605 as non-END. Univariate and multivariate Logistic regression analysis was used to screen out the National Institutes of Health stroke scale [NIHSS, odds ratio (OR) = 1.049, 95% confidence interval (95%CI) was 1.015-1.082, P = 0.004], systolic blood pressure (OR = 1.013, 95%CI was 1.004-1.022, P = 0.004), lymphocyte percentage (LYM%, OR = 0.903, 95%CI was 0.853-0.953, P < 0.001), platelet to lymphocyte ratio (PLR, OR = 1.007, 95%CI was 1.002-1.014, P = 0.013) were the independent predictors of END in AIS patients after intravenous thrombolysis. The area under the curve (AUC) of LR, KNN, SVM, and RF machine learning models in the test dataset were 0.789 (95%CI was 0.675-0.902), 0.797 (95%CI was 0.685-0.910), 0.851 (95%CI was 0.751-0.952) and 0.809 (95%CI was 0.699-0.919), respectively. The RF model had the highest sensitivity (95.7%). The accuracy (0.736), specificity (72.0%) and AUC of SVM model were the highest, and its overall prediction ability was better than the other three models.@*CONCLUSIONS@#Machine learning models have a potential role in early predicting the risk of END after intravenous thrombolysis in AIS patients, and can provide help in clinical decision-making for intravenous thrombolysis.

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OBJECTIVE@#To observe the effects of Xingnao Kaiqiao (regaining consciousness and opening orifices) acupuncture therapy on the expression of hypoxia-inducible factor 1α (HIF-1α) and Nod-like receptor protein 3 (NLRP3) in cerebral ischemia-reperfusion rats, and to explore the mechanism of acupuncture against cerebral ischemia-reperfusion injury.@*METHODS@#Seventy-two male SD rats were randomly divided into a sham-operation group, a model group, an acupuncture group and a non-point acupuncture group, with 18 rats in each one. Using modified Longa thread embolization method, the rat model of acute focal cerebral ischemia was prepared; and after 2 h ischemia, the reperfusion was performed to prepared the model of cerebral ischemia-reperfusion. Immediately after reperfusion, Xingnao Kaiqiao acupuncture method was applied to bilateral "Neiguan" (PC 6) and "Shuigou" (GV 26) in the acupuncture group, while in the non-point acupuncture group, acupuncture was delivered at non-points and all of the needles were retained for 30 min in these two groups. The samples were collected 24 h after reperfusion in the rats of each group. Zea-Longa neurological deficit score was used to evaluate the degree of cerebral neurological impairment, TTC staining was adopted to observe the volume percentage of cerebral infarction, HE staining was provided to observe the morphological changes of brain, and Western blot was applied for detecting the expression of HIF-1α and NLRP3 proteins in the cerebral cortex on the right side.@*RESULTS@#Compared with the sham-operation group, neurological deficit score and volume percentage of cerebral infarction were increased in the model group (P<0.01), and HIF-1α and NLRP3 protein expression was elevated (P<0.01). Compared with the model group, neurological deficit score and volume percentage of cerebral infarction were decreased (P<0.01), and HIF-1α and NLRP3 protein expression was lower (P<0.01) in the acupuncture group. There was no significant difference in above indexes in the non-point acupuncture group compared with the model group (P>0.05). Compared with the sham-operation group, the brain tissue of the rats in the model group and the non-point acupuncture group was loose and edema, and the nuclei were shriveled. The brain tissue morphology in the acupuncture group was similar to that of the sham-operation group.@*CONCLUSION@#Acupuncture can alleviate cerebral ischemia-reperfusion injury, and its mechanism may be related to the regulation of HIF-1α/NLRP3 signaling pathway to attenuate inflammatory response.

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Ischemic stroke caused by acute large vessel occlusion is associated with high rates of disability and mortality. Endovascular interventional therapy is evidently an effective treatment for occlusion of large cerebral vessels within the relevant time window, but there is no established methodological standard for recanalization interventional therapy. The Professional Committee of Interventional Neurology in Chinese Research Hospital Association organized cerebrovascular disease experts in China and developed the expert consensus described herein, to provide a reference for clinicians to formulate technical strategies for recanalization of acute cerebral vascular occlusion.