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The pathogenesis and development of Moyamoya disease are still unclear. This study aimed to investigate the effect of desmoglein-2 (DSG2) on Moyamoya disease and determine the inhibitory effect of DSG2 in vascular remodeling in Moyamoya disease. RNA sequencing, immunohistochemistry (IHC), and western blotting were used to detect the expression of DSG2 in the superficial temporal artery (STA) tissues of Moyamoya disease. The association between DSG2 and endothelial cells' biological activities was investigated by cell counting kit-8 (CCK-8), migration assay, tube formation assay, flow cytometry with Annexin V-FITC/PI staining, and TUNEL apoptotic cell detection kit. Pathways affected by overexpression or knockdown of DSG2 were identified in endothelial cells. The expression of DSG2 in the STA tissues of Moyamoya disease was lower than that in normal controls. Overexpression of DSG2 inhibits the proliferation and migration but promotes apoptosis in endothelial cells, and low DSG2 levels result in impaired angiogenesis. In addition, there was an interaction between DSG2 and MMP-9, and DSG2 acted through the PI3K signaling in endothelial cells. Our results indicate that DSG2 affects PI3K signaling in vascular endothelial cells, and MMP-9 is involved in DSG2-mediated vascular changes in Moyamoya disease. [ABSTRACT FROM AUTHOR]

Background: Samii Type-D jugular foramen schwannomas (JFSs) are the most challenging for neurosurgeons because of anatomical complexity. Various neurosurgical approaches have been described to gain access to JF. Methods: We present a female with incidental diagnosis of the Type-D JFS. Complete radical resection was achieved via the carotid triangle approach without any bony structure removal. And the patient was discharged asymptomatic and without new-developed neurological deficits. Conclusions: The carotid triangle is a secure and appropriate approach for some cases of selected Type-D JFSs. However, the specific indications of this approach should be further explored and investigated. [ABSTRACT FROM AUTHOR]

To study the working mechanism and failure causes of semi-sealed ram blowout preventer, the full-size simulation model of semi-sealed ram is established in this paper. The failure analysis and strength evaluation of semi-sealing ram are carried out. The simulation of the blowout preventer ram in the process of well sealing under different well pressure impacts is studied, and the stress and strain distribution law is found out, and the causes of rubber core seal failure are analyzed. The analysis results show that the groove root of the ram body just enters the yield deformation when the oil cylinder pressure exceeds a certain value, and the maximum von Mises stress occurs at the groove root of the ram body, and the stress concentration and fluid impact pressure lead to the premature fracture failure of the ram. It is also found that the stress concentration in the contact area between the rubber core and the upper end of the ram is the most obvious, indicating that the upper part of the rubber core is severely deformed due to extrusion because of well pressure, which will cause fatigue damage to the rubber core over time. Finally, the extrusion behavior of the contact part between the ram and the drill pipe is highly consistent with the shape of the high-stress zone in the simulation analysis, which proves that the simulation result is reliable. [ABSTRACT FROM AUTHOR]

Whether surgical revascularization can prevent recurrent hemorrhage in hemorrhagic moyamoya disease (HMD) patients remains a matter of debate. This study mainly aims at the comparison of treatment effect between surgical revascularization and conservative treatment of adult HMD patients. We retrospectively enrolled 322 adult HMD patients, including 133 in revascularization group and 189 in conservative group. The revascularization group included patients who underwent combined (n = 97) or indirect revascularization alone (n = 36). Ninety-two and forty-one patients underwent unilateral and bilateral revascularization respectively. The modified Rankin scale (mRS) was used to assess the functional status. The comparison was made based on initial treatment paradigm among two categories: (1) revascularization vs. conservative, (2) unilateral vs. bilateral revascularization. The rebleeding rate was significantly lower in revascularization group than that in conservative group (14.3% vs. 27.0%, P = 0.007). As for the functional outcomes, the average mRS was significantly better in revascularization group (1.7 ± 1.5) than that in conservative group (2.8 ± 1.9) (P < 0.001). The death rate in revascularization group was 8.3% (11/133), comparing to 20.1% (38/189) in conservative group (P = 0.004). While comparing between unilateral and bilateral revascularization within the revascularization group, the result demonstrated lower annual rebleeding rate in bilateral group (0.5%/side-year) than that in unilateral group (3.3%/side-year) (P = 0.001). This study proved the better treatment efficacy of surgical revascularization than that of conservative treatment in HMD patients, regarding both in rebleeding rate and mortality rate. Furthermore, bilateral revascularization seems more effective in preventing rebleeding than unilateral revascularization. [ABSTRACT FROM AUTHOR]