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Background Recurrent hydrocephalus may occur as a complication of neurosarcoidosis with chronic inflammation. We present a case that required a combination of multistage endoscopic diversion of the cerebrospinal fluid pathway and shunt surgery. Case Description A 34-year-old man presented with progressive nausea and vomiting. Magnetic resonance imaging revealed hydrocephalus with leptomeningeal enhancement along the base of the fourth ventricle and the bilateral foramina of Luschka. Concurrent endoscopic third ventriculostomy and biopsy were performed. The diagnosis was neurosarcoidosis. Immediately after the procedure, the endoscopic third ventriculostomy stoma was occluded, and a right ventriculoperitoneal shunt was urgently performed. However, left unilateral hydrocephalus developed during the late phase of immunosuppressive therapy for neurosarcoidosis. Endoscopic septostomy with repositioning of the ventricular catheter was indicated. Intraoperative findings included a white pasty tissue with nodules that covered the ventricular wall close to the foramen of Monro and sealed the side holes of the catheter. Chemotherapy with a tumor necrosis factor–α inhibitor was initiated after the surgical procedure. The patient had an uneventful course without recurrence of hydrocephalus for >6 months. Conclusions Endoscopic diversion of the cerebrospinal fluid pathway should be actively considered for treating hydrocephalus without a shunt and performing biopsy simultaneously. Even if a subsequent shunt is needed, complex hydrocephalus can be avoided with a combination of endoscopic techniques.

Author, Orthovanadate (OV), an inhibitor of protein tyrosine phosphatases, affects various biological processes in a cell-type-specific manner. In this study, we investigated the effect of OV on hepatic stellate cells (HSCs). When primary rat HSCs were cultured in the presence of 10% serum, they spontaneously lost characteristic stellate morphology, proliferated, and were transformed into an activated state with the formation of abundant stress fibers and increased expression of both alpha-smooth muscle actin and collagen type I mRNA. OV treatment inhibited proliferation and activation of HSCs and partially reversed the phenotype of activated HSCs. Among the signaling molecules investigated, phosphorylation of the Src protein at tyrosine 416 was the most striking in OV-treated HSCs. Treatment of cells with Src family inhibitors partially abrogated the effects of OV. Furthermore, transfection of v-Src into activated HSCs induced a stellate morphology similar to that in the quiescent state. We then examined whether OV could effectively suppress HSC activation in vivo after liver injury induced by either carbon tetrachloride or dimethylnitrosamine. OV significantly reduced the appearance of alpha-smooth muscle actin-positive cells and decreased collagen deposition, concomitant with an improvement in liver function. Our study showed for the first time that OV was able to suppress the activation of HSCs, possibly through the modulation of Src activity, and attenuated fibrosis after chronic liver injury.

To elucidate the mechanism of apoptosis of liver sinusoidal endothelial cells (SECs), we examined the phosphorylation status of Bad and its upstream signaling molecules during apoptosis in culture and after ischemia-reperfusion injury. Rat SECs were isolated by the immunomagnetic method, and 2 days after culture, most SECs underwent apoptosis, which was associated with decreased tyrosine phosphorylation of cellular proteins. Addition of orthovanadate (OV), a protein tyrosine phosphatase inhibitor, sustained cellular protein phosphorylation and strongly inhibited apoptosis. Bad was dephosphorylated at Ser-112 and Ser-136 during apoptosis, but the phosphorylation status of Bad was maintained in the presence of OV. OV activated the Akt, extracellular signal-regulated protein kinase, and p38 mitogen-activated protein kinase pathways, which are involved in Bad phosphorylation. In the absence of OV, depletion of Bad by RNA interference conferred resistance to apoptosis. Hepatic injury after ischemia-reperfusion was alleviated by OV treatment, with significant inhibition of SEC apoptosis. SEC apoptosis in vivo was associated with dephosphorylation of Bad, Akt, and extracellular signal-regulated protein kinase, which was blocked by OV treatment. Our data suggest that maintenance of Bad phosphorylation is important in the prevention of SEC apoptosis and that the anti-apoptotic property of OV might have therapeutic utility.

Background/Aims : To develop a specific isolation method of hepatic sinusoidal endothelial cells (SEC), we applied the immunomagnetic method using a monoclonal antibody (SE-1) that recognizes a membranous antigen expressed only in rat SEC. Methods : Cells were isolated by incubating mixed non-parenchymal cells, which were obtained by collagenase digestion of the liver, with SE-1-conjugated superparamagnetic polystyrene beads. The conventional Percoll method was also performed in parallel to compare with the immunomagnetic method. The isolated cells were cultured on glass coverslips coated with type I collagen in the presence of various growth factors for 6 days. Results : Approximately 98% of the isolated cells were positive for SE-1 and the contamination of Kupffer cells or stellate cells was less than 1%. The purity was significantly better than that obtained by the Percoll method. The cultured cells showed typical SEC features, such as sieve plates and uptake of acetylated low-density lipoprotein. Although the cells continuously underwent apoptotic cell death after 2 days, they started robust cell growth after 3 days and were well maintained during the culture period. Conclusions : Our simple and specific isolation method enables us to culture SEC with high purity and should be useful for the biological analysis of SEC.