Ning Xu’s research while affiliated with Jilin University and other places

Introduction Extracellular vesicles (EVs) are nanosized membrane vesicles that are naturally secreted by almost all cells and have gained considerable attention. Many studies have applied EVs to the treatment of brain diseases and validated their effectiveness. Although only a few EVs can penetrate the blood‒brain barrier (BBB) into the brain after administration, it has been proven that EVs and their cargos exert their effects by interacting with brain cells. PKH dyes are commonly used to stain EVs for distribution studies. However, systematic investigations of imaging characteristics of the PKH-labeled EVs distributed in the brain are still scarce. Methods We stained EVs derived from mesenchymal stem cells with PKH26 or PKH67. PKH26-labeled EVs and PKH67-labeled EVs were administered at the same time into each mouse while PKH26-labeled EVs were given through tail veins and PKH67-labeled EVs were given through intraperitoneal injection. Confocal microscopy was used to explore the distribution difference of two types of EVs given via different routes in the brain. Results The fluorescence of PKH26 and PKH67 had nearly identical distributions in brain slices after 1 h, 6 h, 12 h and 1 day of EV administration. Under the same confocal parameters, brain slices without EVs administration demonstrated the same result. However, liver slices from mice administered with labeled EVs showed obviously different distributions of two types PKH fluorescence. Discussion These findings raise questions about the ability of PKH dyes as labels for EVs when explore the EV brain distribution observed via confocal microscopy.

Background and purpose Favorable wall apposition of a flow diverter (FD) is essential for the treatment of intracranial aneurysms. The irretrievability and final drop point uncertainty of the proximal tail of the FD increase the difficulty of achieving good tail apposition. Therefore, understanding the factors associated with FD tail malapposition would be helpful for clinical practice. Methods A total of 153 patients with 161 FD deployments in the carotid artery between 2020 and 2023 were retrospectively collected from our center’s database for this study. Patient demographics, aneurysm characteristics, FDs, carotid artery anatomy, periprocedural complications, discharge modified Rankin scale (MRS) scores, and follow-up outcomes were investigated by comparing patients with and without FD tail malapposition. Comparisons were made with t tests or Kruskal–Wallis tests for continuous variables and the Pearson χ² or Fisher exact test for categorical variables. Logistic regression was conducted to determine the predictors of malapposition. Results Tail malapposition occurred for 41 out of the 161 FDs (25.5%). Univariate analysis revealed that the FD brand, FD length, FD distal to proximal vessel diameter ratio, FD tail position (straight or curved), and curvature of the vessel curve were significantly associated with FD tail malapposition (p < 0.05). Further multivariate analysis demonstrated that the application of a surpass FD (p = 0.04), the FD distal to proximal vessel diameter ratio (p = 0.022), the FD tail position (straight or curved) (p < 0.001) and the curvature of the vessel curve (p < 0.001) were factors significantly associated with FD tail malapposition. No significant difference was found in periprocedural or follow-up outcomes. The classification of FD tail malapposition was determined from imaging. The two major patterns of FD tail malapposition are unattached tails and protrusive tails. Conclusion FD tail malapposition might be associated with a larger FD distal to the proximal vessel diameter difference, a curved vessel where the FD tail is located, and a larger curvature of the vessel curve. FD tail malapposition can be classified into unattached tails and protrusive tails, which have their own characteristics and should be noted in clinical practice.

Background The primitive hypoglossal artery (PHA) is an anastomotic vessel of the carotid-basilar artery system that is prevalent only transiently during the embryonic period. Persistent primitive hypoglossal artery (PPHA) is a rare vessel variation in which PHA exists persistently in adulthood and occurs in approximately 0.02–0.1% of the population. Tortuosity of the extracranial internal carotid artery (ICA) is relatively common, impacting 10–43% of the population, and is caused by either congenital or acquired factors. It is still unknown whether PPHA and tortuosity of extracranial ICA are associated. Here, we present a case report of the concurrence of three types of pathologies of the carotid artery: extreme coiling of the extracranial internal carotid artery, multiple aneurysms and persistent primitive hypoglossal artery. Case description A 66-year-old woman suffered intermittent headaches, dizziness and numbness of the right eyelid for 5 years. Magnetic resonance angiography performed in a local hospital reported an aneurysm of the posterior communicating artery segment of the left ICA and a left PPHA. Digital subtraction angiography conducted after admission showed a PPHA originating from the left cervical ICA and an extremely coiling segment of the ICA distal to the beginning of PPHA. Except for the aneurysm of the posterior communicating artery segment of the left ICA, multiple aneurysms were found at the coiling segment of the ICA. Conclusion To the best of our knowledge, this is the first report of PPHA accompanied by an adjacent, extremely coiling ICA. There are no reports of similar tortuous ICAs to this extent or at this position. Including aneurysms, three types of pathologies suggest their congenital origin, and a review of the literature infers the probable association of these lesions.

Objective: Sentinel headache (SH) is considered as a signal of the impending rupture of an aneurysm. However, it is difficult to diagnose whether the headaches of patients are associated with unstable aneurysms. Therefore, there is some doubt about the importance of headaches in patients with unruptured intracranial aneurysms (UIAs). This study was performed to explore the existence and clinical characteristics of SH associated with aneurysms. Methods: Thirty-six patients with a single UIA were collected in this study. Patients were symptomatically categorized into two groups: SH and non-SH. The PHASES scores and patient and aneurysm characteristics were analyzed. Two independent MRI experts who were blinded to the patients' clinical history conducted the analysis of the SWI results. Results: There were 15 patients with sentinel headache. No significant difference was found in patient's basic information and history. The SH group had a higher PHASES score than the non-SH group (P < 0.05). In univariable analysis, abnormal SWI signals were significantly more frequent in the SH group (P < 0.01) and the inflow angle was significantly lower in the non-SH group (P < 0.05). In multivariable analysis, abnormal signals in SWI were an independent factor associated with SH (P < 0.01). Conclusions: SH exists in patients with UIAs and may indicate a high risk of aneurysm rupture. Abnormal signals on SWI may serve as a clinical feature to identify aneurysm-related SH and be helpful for the formulation of therapeutic strategy. Aneurysm geometry may also be related to SH but need further studies in the future.

Rationale: The incidence of pure arterial malformations is relatively low, and few cases have been reported. Only 2 cases with pure arterial malformation have been reported to receive surgery or endovascular treatment. Patient concerns: We report 3 cases and review the relevant literatures. The head examinations of the patients suggested the presence of high-density shadows in front of the pons and midbrain, the dilation of the supraclinoid segment of the right internal carotid artery, and moyamoya in the left brain with an aneurysm-like expansion located on the left posterior communicating artery respectively. After admission, head digital subtraction angiography (DSA) was performed. Diagnoses: Digital subtraction angiography (DSA) for these 3 patients showed that the left posterior communicating artery, the supraclinoid segment of the right internal carotid artery, and the left posterior communicating artery appeared dilated, tortuous, and spirally elongated. In addition, the lesions in the latter 2 patients were accompanied with local aneurysmal changes. Interventions: Two patients were given conservative treatment, and another patient was given endovascular treatment. A head DSA was reviewed 6 months after therapy. Outcomes: The prognosis status of the 3 patients was good. Two patients in the conservative treatment group showed no changes in the lesions on head DSA examination. The DSA examination of the third patient indicated that the vascular remodeling of the diseased vessels was good, the blood vessels were unobstructed, and the aneurysms had disappeared. Lessons: Pure arterial malformations mostly occur in young women and may involve any blood vessels in the brain. It can be accompanied with local aneurysms and calcification. The patients are often given conservative treatment but need to be reviewed regularly. However, it is beneficial to give endovascular treatment to the patients with local aneurysms.

Rationale: Fenestration of the basilar artery is most common in the proximal portion near the vertebrobasilar artery junction. Conversely, fenestration of the middle and distal portions of the basilar artery is not common, and fenestration of the basilar artery with an aneurysm is even less common. Patient concerns: This study reports the case of a 37-year-old woman with basilar artery fenestration malformation and an aneurysm at the mid-distal junction; her symptoms included sudden headaches with nausea and vomiting. Diagnoses: Head digital subtraction angiography showed fenestration at the junction of the middle and upper portions of the basilar artery associated with an aneurysm, and spontaneous pseudoaneurysm formation could not be excluded. Interventions: The patient underwent stent-assisted fenestration and channel occlusion. Outcomes: Five months later, no abnormalities were found by head magnetic resonance imaging. The stents were well positioned, and no occluded branches or aneurysms were present. Lessons: For mid-distal basilar artery fenestration malformation with an aneurysm, occlusion of the lesion channel is relatively safe when there are no perforating vessels in the fenestration channel and the lesion channel is a nondominant channel. Overall, more attention should be paid to the possibility of pseudoaneurysm formation in the diagnosis and treatment of this type of aneurysm.

The primitive trigeminal artery is an anastomotic vessel of the carotid–basilar artery system that occurs only transiently during the embryonic period. Persistent primitive trigeminal artery occurs in approximately 0.1–0.6% of the population. Here, we report the case of a 60-year-old woman with Fisher II grade subarachnoid haemorrhage. Computed tomography angiography demonstrated a lateral, Saltzman type I persistent primitive trigeminal artery with three cerebral aneurysms, including one anterior communicating artery aneurysm, one suspicious right anterior choroidal artery aneurysm and one distal basilar artery aneurysm supplied by the persistent primitive trigeminal artery. All three aneurysms were treated with coil embolisation. At the 8-month follow-up, the anterior communicating artery aneurysm had a neck remnant, the other two aneurysms exhibited complete occlusion. Persistent primitive trigeminal artery with multiple cerebral aneurysms is extremely rare, and only seven cases of persistent primitive trigeminal artery with multiple cerebral aneurysms have previously been reported in publications that included information on treatment. Most aneurysms were treated by open surgery. This is the first report of coil embolisation treatment of multiple aneurysms in persistent primitive trigeminal artery patients with follow-up results, and provides relevant and valuable information about the persistent primitive trigeminal artery and the endovascular treatment of multiple aneurysms in persistent primitive trigeminal artery patients.

Background: Stent-jailing and stent-jack are used for stent-assisted coil embolism (SCE) in intracranial aneurysm (IA) therapy, and cause different incidences of IA recurrence. Angiogenesis strongly correlates with aneurysm accumulation. Stent-jack causes higher mechanical forces in cerebral vessels than stent-jailing. Mechanical forces, as well as TGF-β/Smad2,3,4 signaling pathway, may play an important factor in IA recurrence by affecting angiogenesis. Methods: We explored the effects of stent-jailing or stent-jack technique on IA recurrence by investigating mechanical forces, TGF-β/Smad2,3,4 signaling pathway and the incidence of angiogenesis in IA patients. One-hundred-eighty-one IA patients were assigned into stent-jailing (n = 93) and stent-jacket groups (n = 88). The clinical outcome was evaluated using Glasgow Outcome Score (GOS) and aneurysm occlusion grades. The percentage of CD34⁺EPCs (releasing pro-angiogenic cytokines) in peripheral blood was measured by flow cytometer. Endothelial cells were separated from cerebral aneurysm and malformed arteries via immunomagnetic cell sorting. Angiogenesis was measured by microvessel density (MVD) using anti-CD34 monoclonal antibody staining before using the stent, immediately after surgery and 2 years later. Meanwhile, the mechanical forces in cerebral vessels were determined by measuring endothelial shear stress (ESS) via a computational method. TGF-β and Smad2,3,4 were measured by real-time qPCR and Western Blot. Tube formation analysis was performed to test the relationship between angiogenesis and TGF-β, and the effects of different techniques on angiogenesis. Results: After a 2-year follow-up, 85 and 81 patients from stent-jailing and stent-jack groups, respectively, completed the experiment. Stent-jailing technique improved GOS and reduced aneurysm occlusion grades higher than the stent-jack technique (P < 0.05). The counts of CD34⁺EPCs and MVD values in the stent-jailing group were lower than the stent-jack group (P < 0.05). ESS values in sent-jailing group were lower than the stent-jack group (P < 0.05), and positively correlated with MVD values (P < 0.05). TGF-β and Smad2,3,4 levels in sent-jailing group were also lower than the stent-jack group (P < 0.05). TGF-β was associated with angiogenesis incidence and stent-jack caused angiogenesis incidence more than stent-jailing. Conclusion: Stent-jailing technique reduces IA recurrence more than stent-jack by causing less mechanical forces, angiogenesis and inhibiting TGF-β/Smad2,3,4 signaling in IA patients.

A 45-year-old Chinese man presented with acute severe headache for 2 days. He was diagnosed as subarachnoid hemorrhage. Head CT and subsequent head digital subtraction angiography (DSA) showed left internal carotid artery (ICA) aneurysm in the supraclinoid segment. Stent-assisted coil embolization of aneurysm was performed. Three hours after the surgery, the patient was found to be drowsy and with paralysis of the right limb and slurred speech. Urgent head CT examination ruled out acute hemorrhage; however, DSA showed acute thrombosis in the left ICA between the branches of the ophthalmic artery and middle cerebral artery, which was probably from an acute in-stent thrombosis. Urokinase (100,000 units) was given through a micro-tube but failed to dissolve the thrombus; thus, stent embolectomy was performed, which successfully removed the thrombus. Repeat angiography showed that the left ICA was completely recanalized. Postoperatively, the patient regained consciousness and was well-limbed and fluent in speech. No neurological symptoms or signs were found at 6-, 12-, and 24-month follow-up.

Background/Aims: Transient receptor potential cation channel 1 (TRPC1)-mediated the calcium (Ca²⁺) influx plays an important role in several brain disorders. However, the function of TRPC1 in ischemia/reperfusion (I/R)-induced neurological injury is unclear. Methods: Wild-type or TRPC1 knockout mice underwent middle cerebral artery occlusion for 90 min followed by 24 h of reperfusion. In an in vitro study, neuronal cells were treated with oxygen-glucose deprivation and reoxygenation (OGD/R) to mimic I/R. The intracellular Ca²⁺ concentration [Ca²⁺]i was measured by Fura 2-AM under a microscope. Cerebral infarct volume was measured by triphenyltetrazolium chloride staining. Neurological function was examined by neurological severity score, Morris water maze test, rotarod test and string test. Oxidative parameters were detected by malondialdehyde, glutathione peroxidase, and superoxide dismutase commercially available kits. The protein expression levels of TRPC1, Nox4, p22phox, p47phox, and p67phox were analyzed by western blotting. Results: Brain tissues from cerebral I/R mice showed decreased TRPC1 expression. Similarly, TRPC1 expression was reduced in HT22 cells upon exposure to OGD/R treatment, followed by decreased Ca²⁺ influx. However, TRPC1 overexpression reversed the OGD/R-induced decrease in [Ca²⁺]i. TRPC1 knockout significantly exacerbated I/R-induced brain infarction, edema, neurological severity score, memory impairment, neurological deficits, and oxidative stress. In contrast, TRPC1 upregulation inhibited the increase in reactive oxygen species (ROS) generation induced by OGD/R. Analysis of key subunits of the Nox family and mitochondrial ROS revealed that the effects of TRPC1 downregulation on oxidative stress were associated with activation of Nox4-containing NADPH oxidase. TRPC1 interacted with Nox4 and facilitated Nox4 protein degradation under OGD/R conditions. In addition, TRPC1 inhibition potentiated the OGD/R-induced translocation of p47phox and p67phox as well as the interaction between Nox4 and p47phox or p67phox, whereas TRPC1 overexpression had the opposite effects. Conclusion: TRPC1 deficiency potentiates ROS generation via Nox4-containing NADPH oxidase, which exacerbates cerebral I/R injury. TRPC1 may be a promising molecular target for the treatment of stroke.