Use of a micromanipulator system (NeuRobot) in endoscopic neurosurgery.

NeuRobot, a micromanipulator system with a rigid neuroendoscope and three micromanipulators, was developed for less invasive and telecontrolled neurosurgery. This system can be used to perform sophisticated surgical procedures through a small, 10-mm-diameter, window. The present study was performed to evaluate the feasibility of using NeuRobot in neuroendoscopy. Four different intraventricular neurosurgical procedures were simulated in three fixed cadaver heads using NeuRobot: (1) fenestration of the floor of the third ventricle; (2) fenestration of the septum pellucidum; (3) biopsy of the thalamus; and (4) biopsy of the choroid plexus of the lateral ventricle. Each procedure required less than 2 min, and all procedures were performed accurately. After these surgical simulations, a third ventriculostomy was carried out safely and adequately in a patient with obstructive hydrocephalus due to a midbrain venous angioma. Our results confirmed that NeuRobot is applicable to lesions in which conventional endoscopic neurosurgery is indicated. Furthermore, NeuRobot can perform more complex surgical procedures than a conventional neuroendoscope because of its maneuverability and stability. NeuRobot will become a useful neurosurgical tool for dealing with lesions that are difficult to treat by conventional neuroendoscopic surgery.

Br-DIF-1 accelerates dimethyl sulphoxide-induced differentiation of P19CL6 embryonic carcinoma cells into cardiomyocytes.

BACKGROUND AND PURPOSE: Stem cell transplantation therapy is a promising option for treatment of severe ischaemic heart disease. Dimethyl sulphoxide (DMSO) differentiates P19CL6 embryonic carcinoma cells into cardiomyocyte-like cells, but with low differentiation capacity. To improve the degree of this differentiation, we have assessed several derivatives of the differentiation-inducing factor-1 (DIF-1), originally found in the cellular slime mould Dictyostelium discoideum, on P19CL6 cells. EXPERIMENTAL APPROACH: P19CL6 cells were cultured with each derivative and 1% DMSO for up to 16 days. Differentiation was assessed by measuring the number of beating and non-beating aggregates, and the expression of genes relevant to cardiac tissue. The mechanism of action was investigated using a T-type Ca(2+) channel blocker. KEY RESULTS: Of all the DIF-1 derivatives tested only Br-DIF-1 showed any effects on cardiomyocyte differentiation. In the presence of 1% DMSO, Br-DIF-1 (0.3-3 µM) significantly and dose-dependently increased the number of spontaneously beating aggregates compared with 1% DMSO alone, by day 16. Expression of mRNA for T-type calcium channels was significantly increased by Br-DIF-1 + 1% DMSO compared with 1% DMSO alone. Mibefradil (a T-type Ca(2+) channel blocker; 100 nM) and a small interfering RNA for the T-type Ca(2+) channel both significantly decreased the beating rate of aggregates induced by Br-DIF-1 + 1% DMSO. CONCLUSIONS AND IMPLICATIONS: Br-DIF-1 accelerated the differentiation, induced by 1% DMSO, of P19CL6 cells into spontaneously beating cardiomyocyte-like cells, partly by enhancing the expression of the T-type Ca(2+) channel gene.

Prediction of functional outcome in acute cerebral hemorrhage using diffusion tensor imaging at 3T: a prospective study.

BACKGROUND AND PURPOSE: Early evaluation of the pyramidal tract is a prerequisite in patients with intracerebral hemorrhage (ICH) in order to decide the optimal treatment or to assess appropriate rehabilitation. The aim of this study was to evaluate and predict the neuromotor and functional outcome of an ICH by using diffusion tensor imaging (DTI) in the acute phase. MATERIALS AND METHODS: Eighteen patients with a hemiparetic supratentorial ICH were prospectively studied with DTI within 2 days after onset. A region-of-interest-based analysis was performed for the fractional anisotropy (FA) of the pyramidal tract in the cerebral peduncles. The degree of paresis was assessed at day 0 and day 28 by paresis grading (PG). The functional outcome was evaluated by the modified Rankin Scale (mRS). RESULTS: The FA in the affected side was significantly lower compared with that of the unaffected side (P = .001) with the mean diffusivity remaining unchanged (P = .50). The ratio of the FA (rFA) in the affected side to the unaffected side was significantly correlated with the PG at day 0 and 28 and the mRS score at day 28 (P = .002, r = -0.674; P < .001, r = -0.767; and P = .002, r = -0.676). The rFA for the good and poor outcomes based on the PG was significantly different (P < .001). The cutoff point of the rFA for the good and poor outcomes was set at 0.85 (sensitivity, 100%, specificity, 100%). CONCLUSIONS: We conclude that DTI can evaluate the motor deficit quantitatively and may predict the functional outcome in patients with an ICH who were scanned within 2 days after the ICH onset.

Dural plasmacytoma mimicking meningioma in a young patient with multiple myeloma.

Intracranial involvement in multiple myeloma (MM) is rarely found, especially with dural involvement. There are only a few cases found concerning MM with intracranial involvement. MM usually involves an older group of patients. Cases involving young patients are very rare. The differential diagnosis of a dural plasmacytoma includes meningioma, metastasis, lymphoma and sarcoma of the dura mater. We present a young patient, 33 years old, with MM presenting an intracerebral mass mimicking meningioma on MRI. MM was diagnosed the previous year. The patient presented with headache, balance disturbance and back pain. MRI revealed an occipital extra-axial mass with a dural tail. Histopathological examination after excision showed MM. Published literatures on intracranial involvement of MM are also discussed. Plasmacytoma should be considered in the differential diagnosis of a solitary dural mass, particularly in a patient with MM.

Nationwide surveillance of IC anterior (or dorsal) wall aneurysm: with special reference to its dissecting nature.

Two hundred and twenty-one cases of IC dorsal aneurysm (ICDA) with subarachnoid hemorrhage (SAH) from 365 cases in the nationwide surveillance of ICDA (NSICDA) data bank were studied with special reference to the dissecting type. Dissection of the internal carotid artery (ICA) was confirmed in 50 out of 221 SAH cases. In 193 surgically treated cases, 40 were of the certified dissecting type. Including those with clinical features which strongly suggests the existence of dissecting changes in the ICA wall, 97 cases (55.6% of operated) were thought to be a dissecting type. Incidence of intraoperative bleeding is significantly higher and surgical outcome is significantly worse in the dissecting type than in the non-dissecting type. Treatment options for this peculiar and formidable aneurysm (An) are described.

Telecontrolled micromanipulator system (NeuRobot) for minimally invasive neurosurgery.

BACKGROUND: To perform less invasive neurosurgery, a telecontrolled micromanipulator system has been developed and applied to clinical situations. Basic experiments for telesurgery have also been conducted. METHOD: A cadaver head was used to carry out surgical simulation of the opening of the sylvian fissure and third ventriculostomy. After obtaining permission from the Ethical Committee of Shinshu University School of Medicine, part of the recurrent meningioma in a 45-year-old man was removed. As basic experiment for telesurgery, surgical simulation was also conducted in a rat brain with the operating console transported to a hospital 40 km distant from the University. FINDINGS: Opening of the sylvian fissure and third ventriculostomy were accurately performed. Tumour removal in a patient with recurrent meningioma was safely achieved. Surgical simulation in the rat brain was accurately and correctly carried out, operated on from a hospital 40 km distant. CONCLUSIONS: The NeuRobot, telecontrolled micromanipulator system, can be used as a tool for less invasive neurosurgery.

Expression of proteinase-activated receptors (PAR)-2 in articular chondrocytes is modulated by IL-1beta, TNF-alpha and TGF-beta.

OBJECTIVE: To investigate the modulation of expression of proteinase-activated receptor-2 (PAR-2) in articular chondrocytes by inflammatory cytokines. DESIGN: Articular synovium and cartilage tissues were collected from eight patients with osteoarthritis (OA), and three patients without arthropathy ("normal"). Chondrocytes were stimulated with interleukin (IL)-1beta, tumor necrosis factor (TNF)-alpha or transforming growth factor (TGF)-beta1. The expression of PAR-2 was detected using reverse transcriptase-polymerase chain reaction (PCR), Western blotting and immunofluorescence. Quantitative PCR was performed to assess the expression levels of PAR-2 messenger RNA (mRNA). RESULTS: The expression of PAR-2 mRNA was demonstrated in both OA and normal chondrocytes as well as in synovial fibroblasts. However, the level of PAR-2 in OA chondrocytes was much higher than in normal chondrocytes. Long-term culture revealed that PAR-2 mRNA expression was maintained up to three passages in OA but not in normal chondrocytes. IL-1beta and TNF-alpha both upregulated PAR-2 expression in normal and OA chondrocytes. In contrast, TGF-beta1 significantly decreased expression of PAR-2 in OA chondrocytes but increased PAR-2 in normal chondrocytes. CONCLUSIONS: Overexpression of PAR-2 in OA chondrocytes is upregulated by proinflammatory cytokines IL-1beta and TNF-alpha, and down-regulated by regulatory cytokine TGF-beta1. PAR-2 may be involved in the pathogenesis of OA.

The role of subchondral bone resorption pits in osteoarthritis: MMP production by cells derived from bone marrow.

OBJECTIVE: The vascular invasion of bone marrow tissue into the subchondral plate is often observed in articular cartilage and we named it the subchondral bone absorption pit; however, its implication in the pathogenesis of osteoarthritis (OA) has been poorly understood. The purpose of this study was to evaluate its characteristics and roles in osteoarthritic conditions. METHODS: Articular cartilage specimens from 11 patients with medial type knee OA and 7 non-arthritic cadavers were analyzed with HE staining. OA sections were stained with safranin-O, TRAP (tartrate resistant acid phosphatase) and immunostained with anti-MMP-1, MMP-3, MMP-13, vitronectin receptor (VNR)-alpha chain, vimentin and bone morphogenic protein (BMP) 2/4 antibodies. RESULTS: Subchondral bone resorption pits were classified according to the extent of invasion: pits with bone marrow tissue were located within uncalcified cartilage below the tidemark in grade I and invaded beyond the tidemark in grade II, while no invasion was seen in grade 0. Grade II pits were dominant in OA compared to non-arthritic joints, especially medial condyles. Proteoglycan detected with safranin-O staining was lost around the tip of grade II pits and the density of pits was related to the modified Mankin Score. Cells in pits expressed vimentin, MMP-1, MMP-3 and MMP-13. Some polynuclear cells co-expressed VNR-alpha chain and MMP-13, whereas pits showed reparative features expressing BMP. CONCLUSION: These results suggest that subchondral bone resorption pits contribute to cartilage degradation by expressing matrix metalloproteinases in OA.

Chemokines differentially induce matrix metalloproteinase-3 and prostaglandin E2 in human articular chondrocytes.

OBJECTIVE: To explore prostaglandin (PG) E2 production by human articular chondrocytes induced by different chemokines. METHODS: Human chondrocytes were enzymatically isolated from the articular cartilage of patients with rheumatoid arthritis (RA), osteoarthritis (OA) or traumatic fracture (N) who underwent total joint replacement. They were cultured in vitro as monolayers and then exposed to MCP-1, RANTES or SDF-1 for 24 h. Levels of PGE2 and MMP-3 in the culture supernatant were then immunoassayed. RESULTS: PGE2 production was enhanced up to 2.7-fold in a subset of samples. Responses to different chemokines were heterogeneous even within the same disease groups. As previously reported, chemokines induced MMP-3 secretion by chondrocytes, but there was no significant correlation between levels of PGE2 and MMP-3. CONCLUSION: We here document the presence of "responders" among OA, RA and normal chondrocytes that produce enhanced levels of PGE2 upon stimulation by chemokines. The relationship between chemokines and prostaglandins could differentially influence the pathogenic network responsible for cartilage degradation in arthropathy.

Inducible expression of p57KIP2 inhibits glioma cell motility and invasion.

To examine the role of p57KIP2 in human malignant glioma cells, we studied its expression in a panel of human malignant glioma specimens by western blot and immunohistochemical analysis. To determine the effects of p57KIP2 expression on the phenotype of glioma cells, we analyzed two inducible stably transfected p57KIP2 expressing glioma cell lines. Expression of p57KIP2 was induced in U373 and U87 malignant glioma cells with doxycycline using the tetracycline repressor system. A phagokinetic track assay on gold particles was used to investigate differences in cell migration between p57KIP2 expressing and non-expressing control cells. The effects of the extracellular matrix (ECM) on U373 motility was determined in p57+ and p57-cells on surfaces coated with 5 microg/cm2 of fibronectin, laminin, type I and type IV collagens. The invasion of p57+ and p57- glioma cells across BD Biocoat Matrigel invasion chambers was then determined. p57KIP2 was weakly expressed in 4/6 glioblastoma (GBM) specimens by western blot. By immunohistochemistry, p57KIP2 immunoreactivity was positive in 8/40 GBMs, and was primarily nuclear in location. The motility of U373 glioma cells was significantly reduced after p57KIP2 induction. The presence of ECM proteins did not further alter the motility of p57+ and p57- glioma cells. The results of the invasion chamber assay showed that p57+ cells exhibited a 35% reduction in their invasive capacity as compared to p57- cells. These data suggest that p57KIP2 is expressed in at least some malignant gliomas. Inducible expression of 57KIP2 in cell lines deficient in this cyclin-dependent kinase inhibitor reduces their otility and invasiveness.

Characterisation of cartilage intermediate layer protein (CILP)-induced arthropathy in mice.

OBJECTIVES: To characterise cartilage intermediate layer protein (CILP)-induced arthropathy in mice. METHODS: The first and second halves of the nucleotide triphosphate pyrophosphohydrolase (NTPPHase) non-homologous region of human CILP were prepared as recombinant proteins (C1 and C2, respectively), including three overlapping fragments of C2 (C2F1, C2F2, and C2F3). C57BL/6 mice were immunised with these proteins to induce arthritis. In addition, a separate group of mice were immunised repeatedly with the mixture of C1 and C2 to see the effect of chronic immunisation. Arthritis developed in the mice, and cellular and humoral immune responses against CILP were analysed. RESULTS: Immunisation with C2 and with the mixture C2F1/C2F2/C2F3 caused the severest arthritis to develop in mice. Immunisation with one of C1, C2F1, C2F2, or C2F3 caused milder arthritis, even though each of the fragments carried T cell epitopes. Immunisation either with C1 or C2 alone evoked cellular and humoral immune responses to both the C1 and C2 proteins. Further, the repeated immunisation with the C1/C2 mixture caused tendon calcification and bone irregularity, together with decreased NTPPH activity. CONCLUSIONS: The results show that multiple T cell epitopes are needed for the development of CILP-induced arthritis, and present the characteristic new model of mild arthropathy accompanied by extra-articular calcifications. An immune response to putative murine CILP/NTPPH may be involved in the ectopic calcifications in the arthritic mice.

Characterization of cells from pannus-like tissue over articular cartilage of advanced osteoarthritis.

OBJECTIVE: To identify the characteristics of cells isolated from pannus-like soft tissue on osteoarthritic cartilage (OA pannus cells), and to evaluate the role of this tissue in osteoarthritis (OA). METHODS: OA pannus cells were isolated from pannus-like tissues in five joints obtained during arthroplasty. The phenotypic features of the isolated cells were characterized by safranin-O staining and immunohistochemical studies. Expression of MMP-1, MMP-3 and MMP-13 was also assessed using reverse transcriptase-polymerase chain reactions (RT-PCR), enzyme-linked immunosorbent assay (ELISA) and immunocytochemistry. RESULTS: Foci and plaque formation of pannus-like tissue over cartilage surface were found in 15 of 21 (71.4%) OA joints macroscopically, and among them, only five samples had enough tissue to be isolated. OA pannus cells were positive for type I collagen and vimentin, besides they also expressed type II collagen and aggrecan mRNA. Spontaneous expression of MMP-1, MMP-3 and MMP-13 was detected in OA pannus cells. Similar or higher levels of MMPs were detected in the supernatant of cultured OA pannus cells compared to OA chondrocytes, and among these MMP-3 levels were relatively higher in OA pannus cells. Immunohistochemically, MMP-3 positive cells located preferentially in pannus-like tissue on the border of original hyaline cartilage. CONCLUSION: Our results showed that OA pannus cells shared the property of mesenchymal cells and chondrocytes; however, their origin seemed different from chondrocytes or synoviocytes. The spontaneous expression of MMPs suggests that they are involved in the articular degradation in OA.

Embolization of Arteriovenous Malformation. Efficacy and Safety of Preoperative Embolization Followed by Surgical Resection of AVM.

SUMMARY: Treatment options for cerebral arteriovenous malformation (AVM) are still controversial due to the recent result of stereotactic radiosurgery and the improved result of microsurgical resection. We investigated previously treated AVM cases and discussed the efficacy and safety of preoperative embolization especially for microsurgical resection of high-grade AVM in the Spetzler-Martin grading. Efficacy of preoperative embolization was evaluated based on 126 previously treated AVM cases at Shinshu University Hospital during the last 25 years. The safety of embolization was evaluated based on our previously-embolized 58 AVM cases (91 procedures) in the last 11 years after introduction of preoperative embolization for AVM. In all 126 cases, 82 were treated before introduction of embolization and 44 were treated after introduction of embolization. In 82 cases of the pre-embolization era, 63 lesions were removed totally in 63 AVMs (77%), partially resected in 11 (13%) and untreated in eight (10%). In 74 surgically removed cases, 11 (15%) cases showed severe intra/postoperative bleeding. In 44 cases of the embolization era, lesions were removed totally in 29 AVMs (66%), disappeared only with embolization in one (2%), disappeared with radiosurgery in seven (16%) and were untreated in five (11%). In 32 surgically removed cases, only one (2%) case showed severe intra/postoperative bleeding. In all 58 embolized cases, 44 were surgically removed, six were treated with radiosurgery, one was eliminated with embolization alone and six were partially obliterated and followed up for their location. In 91 procedures for 58 cases, two haemorrhagic and three ischemic complications occurred, three were transient and two remained having neurological deficits. The introduction of preoperative embolization improved the total removal rate and reduced the intra/postoperative bleeding rate in surgical removal of AVM. The total risk of embolization is low and well-designed preoperative embolization makes surgical resection safer even in high-grade AVM in the Spetzler-Martin grading.

Efficacy of daily compared to intermittent administration of IL-1Ra for protection against bone and cartilage destruction in collagen-challenged mice.

OBJECTIVE: To investigate the protective effect of interleukin-1 receptor antagonist (IL-1Ra) on bone and cartilage destruction in the induction phase of collagen-induced arthritis (CIA), an animal model of rheumatoid arthritis (RA). METHODS: DBA/1J mice were immunized with type II collagen for induction of collagen-induced arthritis (CIA) and simultaneously given different intraperitoneal doses of IL-1Ra daily, thrice weekly or once a week. Clinical symptoms of arthritis were noted daily and assessed using a scoring system during the course of disease. Bone and cartilage destruction in the mice was assessed by radiographic and histological methods respectively. RESULTS: Mice injected with IL-1Ra daily were completely protected from the occurrence of arthritis after immunization with type II collagen. Moreover, these mice were also protected against bone and cartilage destruction. However, weekly or thrice weekly treatment with IL-1Ra had no effect on arthritis and bone and cartilage destruction. CONCLUSION: Daily administration of recombinant IL-1Ra, injected at the same time as arthritis induction, is effective in blocking the occurrence of inflammatory as well as destructive changes in CIA. Daily bolus injections of IL-1Ra may therefore be useful for protection against joint damage following minor joint injury, whereas the maintenance of appropriate blood levels of the antagonist may be critical for its therapeutic effect on chronic inflammatory arthritis.

Presence of pannus-like tissue on osteoarthritic cartilage and its histological character.

OBJECTIVE: To investigate and characterize pannus-like tissue which is often present on osteoarthritic articular cartilage. DESIGN: Cartilage specimens from 15 knee and five hip joints of patients with osteoarthritis (OA) undergoing arthroplasty were stained for HE and Safranin-O. They were also immunostained by antitype I collagen, type II collagen, CD68, IL-1beta and MMP3 antibodies. RESULTS: Ninety percent of joints have pannus-like tissue on the articular surface, preferentially in a marginal area. The articular cartilage was divided into three regions according to the location: the marginal zone, the intermediate zone and the paraeburnated zone. Pannuslike tissue in OA knee joint occurred 45.9%, 27.5% and 11.1% of the surface of each region respectively. Histologically, pannus-like tissue could be classified into the vascular type and the fibrous type. Extracellular matrix of both types of tissues were negative for Safranin-O and type II collagen, but positive for type I collagen. IL-1beta and MMP3 expressing cells are predominant in pannus-like tissue, whereas CD68 positive cells were infiltrated in only a few samples. Vascular type tissue kept continuity with bone marrow suggesting mesenchymal origin. CONCLUSION: Pannus-like tissue exists in advanced OA cartilage, preferentially in the marginal zone. It expressed IL-1beta and MMP3, which strongly suggests that it contributes to cartilage degradation.

Clinical results and pathological findings of stent-assisted coil embolization for basilar artery trunk dissecting aneurysms.

SUMMARY: Stent-assisted coil embolization is a new method for treating dissecting or fusiform aneurysm, especially the aneurysms arising from the basilar artery trunk or dominant vertebral artery. At present, this technique is considered as an effective treatment option to obliterate such aneurysm keeping the parent artery patent. Several authors reported the effectiveness and excellent radiological result of this treatment, but fewer reports focus on the limitations of this technique. We treated two patients with a basilar artery trunk dissecting aneurysm with this technique. Transient ischemic symptoms were observed in one patient and haemorrhagic and thromboembolic complications were observed the other.We lost the latter patient due to postoperative complications, and the pathological finding was achieved by autopsy. We report the clinical and pathological findings in the two cases and investigate the efficacy and limitations of this technique.

Osteoarthritic articular chondrocytes stimulate autologous T cell responses in vitro.

OBJECTIVE: To clarify the presence of specific T cell immune response to autologous chondrocytes in patients with osteoarthritis (OA). METHODS: Peripheral blood mononuclear cells obtained from OA or post-traumatic patients were co-cultured with irradiated autologous chondrocytes, and their proliferative response was assessed using 3H-thymidine incorporation. Expression of HLA-class II molecules was also assessed on chondrocytes by immunohistochemistry or flow cytometry. RESULTS: T cell responses to autologous chondrocytes in OA yielded a significantly greater mean stimulation index (6.35 +/- 1.63) compared to controls (1.21 +/- 0.09, p < 0.01). This response was partially blocked by antibodies against HLA class I, class II, CD4 or CD8. Increased expression of HLA-DP, -DQ, and -DR was observed. CONCLUSION: This study showed the autologous T cell-stimulating property of OA chondrocytes in vitro. The elucidation of the autoimmune responses may contribute to the understanding of immune-mediated mechanisms in OA.

YKL-39, a human cartilage-related protein, induces arthritis in mice.

OBJECTIVE: To determine whether YKL-39, a recently cloned secretory protein of articular chondrocytes, is arthritogenic in mice. METHODS: Recombinant YKL-39 (rYKL-39) was expressed and purified from E. coli. To induce arthritis in mice, rYKL-39 (1, 10 or 50 g in Freund's incomplete adjuvant) was injected into the right footpad of mice from four different strains (BALB/c, DBA/1J, C57BL/6 and ICR). The mice received a second immunization with rYKL-39 by intradermal injection into the root of the tail 10 days after the first immunization. Severity of arthritis was assessed by scoring each paw on a scale from 0 to 4. Sixty days after thefirst immunization, the mice were sacrificed and the joints were examined by immunohistochemistry and radiography. The anti-YKL-39 and anti type II-collagen (CII) antibody titres were also assayed using ELISA. RESULTS: Immunization with YKL-39 induced arthritis in all strains of mice tested, among which BALB/c was most susceptible. Histological examination showed synovial proliferation and irregularity of the cartilage surface in YKL-39-injected BALB/c mice. Moreover radiographic analysis revealed pathological changes in these mice. The YKL-39-immunised mice produced not only anti-YKL-39 antibody but also antibody against type II collagen, suggesting a spreading of autoimmunity after YKL-39. CONCLUSIONS: YKL-39, a cartilage-related protein, is found to induce arthritis accompanied by pathologic changes in bone and cartilage. A better understanding of the immune response against cartilage-related components including YKL-39 may help to elucidate the pathological processes of arthritic disorders.