Yongjie Yuan

Biocompatible PEGylated Fe3O4 nanoparticles as photothermal agents for near-infrared light modulated cancer therapy.

In accordance with the World Cancer Report, cancer has become the leading cause of mortality worldwide, and various therapeutic strategies have been developed at the same time. In the present study, biocompatible magnetic nanoparticles were designed and synthesized as high-performance photothermal agents for near-infrared light mediated cancer therapy in vitro. Via a facile one-pot solvothermal method, well-defined PEGylated magnetic nanoparticles (PEG–Fe3O4) were prepared with cheap inhesion as a first step. Due to the successful coating of PEG molecules on the surface of PEG–Fe3O4, these nanoparticles exhibited excellent dispersibility and dissolvability in physiological condition. Cytotoxicity based on MTT assays indicated these nanoparticles revealed high biocompatibility and low toxicity towards both Hela cells and C6 cells. After near-infrared (NIR) laser irradiation, the viabilities of C6 cells were effectively suppressed when incubated with the NIR laser activated PEG–Fe3O4. In addition, detailed photothermal anti-cancer efficacy was evaluated via visual microscope images, demonstrating that our PEG–Fe3O4 were promising for photothermal therapy of cancer cells.

Research progress on vertebrobasilar dolichoectasia.

Vertebrobasilar dolichoectasia (VBD) is a rare disease characterized by significant expansion, elongation, and tortuosity of the vertebrobasilar arteries. Current data regarding VBD are very limited. Here we systematically review VBD incidence, etiology, characteristics, clinical manifestations, treatment strategies, and prognosis. The exact incidence rate of VBD remains unclear, but is estimated to be 1.3% of the population. The occurrence of VBD is thought to be due to the cooperation of multiple factors, including congenital factors, infections and immune status, and degenerative diseases. The VBD clinical manifestations are complex with ischemic stroke as the most common, followed by progressive compression of cranial nerves and the brain stem, cerebral hemorrhage, and hydrocephalus. Treatment of VBD remains difficult. Currently, there are no precise and effective treatments, and available treatments mainly target the complications of VBD. With the development of stent technology, however, it may become an effective treatment for VBD.

Application of the Chick Embryo Chorioallantoic Membrane in Neurosurgery Disease

The chick embryo chorioallantoic membrane (CAM) is a highly vascularized extraembryonic membrane. Because of its ease of accessibility, extensive vascularization and immunodeficient environment, the CAM has been broadly used in the oncology, biology, pharmacy, and tissue regeneration research. The present review summarizes the application of the CAM in neurosurgery disease research. We focused on the use of the CAM as an assay for the research of glioma, vascular anomalies, Moyamoya Disease, and the blood-brain barrier.

Current Status of the Application of Intracranial Venous Sinus Stenting.

The intracranial venous sinus is an important component of vascular disease. Many diseases involve the venous sinus and are accompanied by venous sinus stenosis (VSS), which leads to increased venous pressure and high intracranial pressure. Recent research has focused on stenting as a treatment for VSS related to these diseases. However, a systematic understanding of venous sinus stenting (VS-Stenting) is lacking. Herein, the literature on idiopathic intracranial hypertension (IIH), venous pulsatile tinnitus, sinus thrombosis, high draining venous pressure in dural arteriovenous fistula (AVF) and arteriovenous malformation (AVM), and tumor-caused VSS was reviewed and analyzed to summarize experiences with VS-Stenting as a treatment. The literature review showed that satisfactory therapeutic effects can be achieved through stent angioplasty. Thus, the present study suggests that selective stent release in the venous sinus can effectively treat these diseases and provide new possibilities for treating intracranial vascular disease.

Calcitonin gene-related peptide protects rats from cerebral ischemia/reperfusion injury via a mechanism of action in the MAPK pathway

The aim of the present study was to investigate the protective function and underlying mechanism of calcitonin gene-related peptide (CGRP) on cerebral ischemia/reperfusion damage in rats. Adult male Wistar rats were selected for the establishment of an ischemia/reperfusion injury model through the application of a middle cerebral artery occlusion. Animals were randomly divided into 6 groups of 24 animals. Drugs were administered according to the design of each group; animals were administered CGRP, CGRP8–37, PD98059 and SB20358. The neurobehavioral scores of the rat cerebral ischemia model in each group were calculated. The infarction range of the rat brain tissues was observed by 2,3,5-triphenyltetrazolium chloride staining. The expression levels of three proteins, phosphorylated c-Jun N-terminal kinase (JNK)/JNK, phosphorylated extracellular signal-regulated protein kinase (ERK)/ERK and p-p38/p38, in the mitogen-activated protein kinase (MAPK) pathway in the brain tissues was detected by western blotting. The results showed that CGRP could improve the neurobehavioral function of the ischemic rats and reduce the infarction range. Western blotting results confirmed that the function of the CGRP was mediated mainly through the reduction of the JNK and p38 phosphorylation and the promotion of ERK phosphorylation. Therefore, the present study confirmed that an increase in the exogenous CRGP could effectively improve ischemia/reperfusion injury of the brain tissue. The mechanisms of action were achieved through a reduction in JNK and p38 phosphorylation and an increase in ERL phosphorylation in the MAPK pathway. These mechanisms were interdependent.

Trigeminal neuralgia caused by brain arteriovenous malformations: A case report and literature review

Few cases of trigeminal neuralgia (TGN) induced by brain arteriovenous malformations (bAVMs) have previously been reported. The present case report described one case of TGN caused by bAVMs in a 32-year-old male patient who suffered from recurrent pain in his right cheek for a period of two years, for whom the seizure frequency and duration of pain increased for 6 months. Magnetic resonance imaging was performed, which demonstrated flow-void signals in the abnormal vessels in the right cerebellopontine angle. Subsequent digital subtraction angiography confirmed the diagnosis of bAVMs, and showed the nidus was fed by the right superior cerebellar and the right anterior inferior cerebellar, and drained into the adjacent venous sinuses on the same side. The patient underwent an interventional embolization treatment. TGN was completely relieved following embolization of the majority of the bAVMs. Pain relief may be associated with blocking of the pulsatile compression of the feeding arteries of the bAVMs, the arterialized draining veins or the malformed niduses following embolization, which is similar to the effects induced by microvascular decompression surgery of the trigeminal nerve. In the present case study and review, the underlying mechanism and treatment strategy of TGN caused by bAVMs were discussed in the context of present case, and a literature review was carried out.

Moyamoya disease associated with arteriovenous malformation and anterior communicating artery aneurysm: A case report and literature review.

Moyamoya disease (MMD) can be associated with an aneurysm or arteriovenous malformation (AVM). However, no case of MMD simultaneously associated with both intracranial aneurysm and AVM has been previously reported. The present study reports the case of a patient with MMD simultaneously associated with both aneurysm and AVM. The patient was a 46-year-old woman presenting with a subarachnoid hemorrhage whose imaging diagnosis of MMD was associated with an aneurysm and AVM. The aneurysm was located in the anterior communicating artery, which was similar to a berry aneurysm caused by hemodynamics. The AVM was located in the posterior circulation. Beyond the presentation of the posterior cerebral artery, the appearance of an artery supplying blood from the middle cerebral artery supported the view that the AVM was congenital and unruptured. Conservative treatment was provided and examination of the patient at follow-up showed good recovery. In addition to the case report, the present study also reviewed the relevant literature in order to compile information on MMD associated with both an aneurysm and AVM.

Effect of recombinant adeno‑associated virus expressing calcitonin gene‑related peptide on chick embryo umbilical artery vasospasm model

In the present study, a recombinant adeno-associated virus vector containing the calcitonin gene related peptide gene (rAAV-CGRP) was constructed and the therapeutic effect of rAAV-CGRP on a chick umbilical artery vasospasm model induced by chick embryo allantoic cavity hemorrhage was investigated. Fresh specific pathogen-free fertilized chicken eggs were randomly divided into a rAAV-CGRP group, an empty vector virus (AAV) group, and a control group, with 24 eggs in each group. An umbilical arterial vasospasm model was established using a needle puncture method on a vein in the chorioallantoic membrane to induce a hemorrhage in the allantoic cavity of 11-day-old chicken embryonated eggs. A total of 24 h after model establishment, 1 ml of rAAV-CGRP and empty vector virus solution of rAAV-CGRP and empty vector virus solution was, respectively, injected into the allantoic cavity in the rAAV-CGRP and AAV groups. Experimental results showed that after 72 h of model establishment, the mortality rates of the 3-, 5- and 7-day subgroups in the rAAV-CGRP group were lower than in the subgroups of the AAV injection group. After 3, 5 and 7 days of model establishment in the rAAV-CGRP group, the cross-sectional area of the inner diameter of the umbilical arteries was larger than that of the AAV group; the vessel wall thicknesses of the rAAV-CGRP group were thinner than in the AAV group. In addition, the concentration of CGRP in chick embryo allantoic fluid significantly increased and was several times higher than in the AAV group (P<0.05). In conclusion, administration of rAAV-CGRP through the allantoic cavity may increase the viability of a vasospasm model induced by chick allantoic cavity hemorrhage, significantly improve umbilical artery vasospasm, and increase CGRP expression in the chick embryo allantoic cavity. This approach also provides a novel experimental model for identifying other target genes for the gene therapy of vasospasm.

Moyamoya disease manifested as multiple simultaneous intracerebral hemorrhages: A case report and literature review

Multiple simultaneous intracerebral hemorrhages (MSIH) caused by Moyamoya disease (MMD) is extremely rare. To date, the clinical manifestations, imaging characteristics and mechanism of MMD-induced MSIH have not yet been elucidated. In order to improve the understanding on such cases, the present study described a rare case of MSIH caused by MMD. A 40-year-old female patient with no history of hypertension or diabetes mellitus experienced a sudden headache followed by coma. Cranial computed tomography (CT) examination revealed MSIH in the left frontal area, temporal lobe and basal ganglia. CT angiography and digital subtraction angiography examinations revealed typical characteristics of MMD. Subsequent to excluding disorders of the blood system and blood coagulation, we concluded that the present case of MSIH was caused by MMD. Hematoma evacuation and decompressive craniectomy were performed with satisfactory results. In addition, after reviewing previous MSIH cases in the literature, potential mechanisms of MMD-mediated MSIH were considered. In conclusion, MMD should be considered as a possible cause of MSIH during diagnosis and treatment. MMD can lead to pathological changes in the fragility of small arteries; therefore, rupture and hemorrhage at one site may induce a transient increase in blood pressure, causing the rupture of small arteries at other sites, and thus leading to MSIH. Hematoma evacuation and decompression should be conducted in selective cases of MMD-induced MSIH in order to achieve a good prognosis.