With the wide development of intra-arterial thrombolysis,the risk factors and the occurrence mechanism of hemorrhagic transformation have drawn great attention.Hemorrhagic tramformation is the most dangerous complication of intra-arterial thrombolysis.The understanding of the occurrence mechanism of hemorrhagic transformation from macroscopic tO microscopic,it is attributed ultimately to the destruction of vascular wall structure or function.The related mechanisms include oxidative stress reaction,leukocyte infiltration and inflammatory reaction,vascular reaction,and extracellular proteolysis.

Remote ischemic postconditioning (RIP) refers to a transient and non-lethal ischemic adaptation in non-vital organs after the vital organs having experienced long-term lethal ischemic injury. Relative to the remote ischemic preconditioning (RIPC),RIP has more value in clinical application. However,RIP is still in the cognitive stage of research. This article reviews the advances in research on RIP of each system.

More than 2 million strokes occur in china each year,most of which are caused by cerebrovascular stenosis. Atherosclerosis is the main reason for cerebrovascular stenosis. The effective treatment of intracranial atherosclerosis can significantly decrease the incidence of stroke. However,at present,about the treatment of intracranial atherosclerotic stenosis has not been standardized. This article reviews about the treatment methods for intracranial atherosclerotic stenosis in recent years and provides the basis for the development of standardized treatment of intracranial atherosclerotic stenosis.

Erythropoietin (EPO) belongs to cytokines.It mainly promotes erythropoiesis in the peripheral blood circulation.Fundamental research shows that EPO can reduce cerebral ischemic injury through a variety of mechanisms,but at the same time,there are many unsolved problems.In addition,the two clinical trial outcomes are also very inconsistent.This article reviews the problems in EPO research.

Currently,thrombolytic therapy is the most effective treatment for acute ischemic stroke.Intravenous recombinant tissue plasminogen activator administered within 3 hours of symptom onset is the only medication approved by U.S.Food and Drug Administration for the treatment of acute ischemic stroke.However,because the time window for intravenous thrombolytic therapy is very short,only a very few patients can reach the hospital for intravenous thrombolytic therapy within 3 hours of onset.Therefore,how to extend the time window of thrombolytic therapy for more patients to have accessed to it and benefit from it have been the concern of researchers.This article reviews about the recent advances in research on extending the time window of thrombolytic therapy.

MiRs display an important role in a variety of biological, physiological and pathological processes, including cell proliferation, differentiation, apoptosis, individual development, occurrence and progress of diseases. Recent studies have discovered that miR?424 is the significant regulatory factor of angiogenesis, and is involved in many diseases such as infectious diseases, vascular diseases, central nervous system diseases and genital system disease. This article reviews the expression, effect and possible mechanisms of miR?424 in non?tumorous diseases.

The pathogenesis of cerebral ischemia is extremely complicated.In vitro models have better controllability.They have important significance for the study of the pathogenesis.This article reviews the commonly used In vitro models and provides references for the future study of the pathogenesis of cerebral ischemia.

A member of miR-16 family, miR-424 has been found to be closely related with tumorigenesis, tumor progrssion, prognosis and therapy.This article reviews the expression changes, roles and possible regulating mechanisms of miR-424 in leukemia and various tumors such as breast, cervical, lung, liver and colorectal cancers.Recent studies have demonstrated that the expression of miR-424 is affected by many factors, and miR-424 could be a biomarker of diagnosis, staging and prognosis in cancers,to identify the area of tumor, and be a target of therapy.

MicroRNA-494 (miR-494) is one of the microRNAs from 14q32.31 miR-gene cluster.Recently, miR-494 was found to closely relate with tumors and other diseases .This article reviews the expression changes , roles and possible regulatory mechanisms of miR-494 in multiple tumors and other hypoxia/ischemia diseases .Recent studies demon-strate that the expression of miR-494 is affected by many factors , and miR-494 could be a biomarker of diagnosis , staging and prognosis in tumors and other diseases , and a target of therapy in future .

AIM: To explore whether the administration of rhG-CSF improve the neurological function after focal cerebral ischemia and observe the expression of fibronectin. METHODS: Injection of 10 ?g?kg -1?d -1 rhG-CSF for 5 days was given subcutaneously to rats undergoing middle cerebral artery occlusion (MCAO). Neurological severity scores (NSS) test was performed. The expression of fibronectin and Brdu were observed by immunohistochemistry. To visualize the cellular colocalization of Brdu and fibronectin, glial fibrillary acidic protein (GFAP) and fibronectin, double fluorescent staining were used. RESULTS: ① NSS at 7th day, 14th day and 21th day of groups undergoing MCAO treated with rhG-CSF were 4.00?0.89, 3.83?1.17, 3.50?1.38, respectively. NSS at 7th day, 14th day and 21th day of the control groups undergoing MCAO were 5.50?1.38, 5.83?1.47,5.66?1.63, respectively. NSS of the treated groups were significantly lower than that of the control groups (P