Force level and strain patterns during bilateral mandibular osteodistraction

PURPOSE

Recent reports have demonstrated that device orientation is important during mandibular distraction osteogenesis. The purpose of this study was to evaluate the force level and strain patterns on the mandible during bilateral osteodistraction with devices oriented either parallel to the body of the mandible or parallel to the sagittal axis of distraction.

MATERIALS AND METHODS

Five unembalmed human cadaver mandibles were placed in a specially designed apparatus for stabilization of the proximal segments during distraction. A force transducer was attached to the lateral aspect of the inferior ramus, and strain gauges were attached to the mandibular bone segments proximal and distal to the distraction device. Lateral force and bone strains were then measured at 5 and 10 mm of distraction. Osteodistraction proceeded first with the devices placed parallel to the mandibular body, then parallel to the axis of distraction.

RESULTS

Significantly greater lateral forces were seen when the devices were oriented parallel to the mandibular body. With this device orientation, increased tensile strains were seen at the labial symphysis and medial ramus, and increased compressive strains were found at the lingual symphysis and lateral ramus. However, when the devices were oriented parallel to the axis of distraction, the forces and strains were not detected.

CONCLUSIONS

The results suggest that device orientation has important biomechanical effects on lateral forces and strain patterns during mandibular osteodistraction.

Molecular analysis for p53 and mdm2 in intracranial germ cell tumors

Intracranial germ cell tumors (ICGTs) are uncommon neoplasms. The histological appearance of ICGTs is indistinguishable from that of the usual testicular germ cell tumors (TGTs). Recently, several reports have associated molecular abnormalities of p53 and mdm2 in TGTs with their malignancies. However, whether ICGTs are associated with molecular abnormalities is still unknown. We analyzed a series of 16 ICGTs for mutations in the TP53 gene by single-strand conformation polymorphisms, and for amplification of the MDM2 gene using differential PCR. In addition, the same 16 tumors were examined for p53 and mdm2 protein overexpression using antibodies directed against p53 [monoclonal antibodies (mAb) 1801 and DO7] and mdm2 (IF2), respectively. Twelve (75%) and 2 (13%) of the 16 ICGTs reacted with DO7 and PAb1801, respectively, and 1 (6%) carried a TP53 gene mutation. Thirteen (81%) of the 16 ICGTs reacted with IF2, and 3 (19%) carried MDM2 gene amplification. The less frequent TP53 gene mutation compared with MDM2 gene amplification, and the frequently expressed p53 and mdm2 protein, are similar to the case for TGTs. It is tempting to speculate that ICGTs might have the same cellular origins as TGTs with abnormalities in p53 and mdm2, which could play an important role of tumorigenesis.

The efficacy of CT arteriography for spinal arteriovenous fistula surgery: technical note

We performed helical computed tomography with contrast injection into feeding arteries through a selectively introduced microcatheter to provide precise definition of the vascular and bony structure of the spine in patients with spinal arteriovenous fistula. This selective CT arteriography reliably showed structures including abnormal epi- and intradural feeding arteries, the fistula, perimedullary draining veins and surrounding vertebrae preoperatively with a minimal contrast medium load. This technique can facilitate safe, minimally invasive surgical obliteration of the fistula and a favorable outcome.

Detection of circulating tumor cells by reverse transcriptase-polymerase chain reaction in patients with resectable non-small-cell lung cancer

OBJECTIVE

We tested whether circulating tumor cells can be detected in the peripheral blood of patients with resectable non-small-cell lung cancer (NSCLC) by reverse transcriptase-polymerase chain reaction (RT-PCR) of carcinoembryonic antigen (CEA) mRNA.

METHODS

We assayed for CEA mRNA by RT-PCR in the peripheral blood, taken at the time of diagnosis before surgical intervention and again 2 to 3 weeks postoperatively, from 103 patients with NSCLC who underwent curative lobectomy. Blood samples taken from 15 patients with interstitial pulmonary fibrosis who underwent an open-lung biopsy and from 32 healthy subjects served as controls.

RESULTS

No control samples were positive for CEA by RT-PCR. Sixty-two (60%) of the preoperative blood samples from the 103 patients with NSCLC were positive. Of these 62 samples, 27 (44%) remained positive even after surgical intervention, whereas the remaining 35 samples (56%) became negative. The incidence of positive CEA mRNA correlated highly with pathologic TNM stage of disease in both the preoperative and postoperative blood samples.

CONCLUSIONS

Many patients with resectable NSCLC have detectable levels of circulating cells expressing carcinoembryonic antigen even after surgical intervention. Such patients may have a higher rate of relapse.

[Study on CAF + medroxyprogesterone acetate (MPA) therapy for advanced or recurrent breast cancer--comparison between MPA 600 mg and 1,200 mg. Kyushu CAFT Therapy Study Group (Third Study)]

To find the optimal dose of MPA for combined use with CAF therapy for advanced or recurrent breast cancer, a randomized comparative study with a MPA 1,200 mg group and 600 mg group was carried out multi-institutionally. The response rate of complete cases was 37.5% (12/32) in the 1,200 mg group and 36.6% (15/41) in the 600 mg group, showing no difference between the two groups. There were no differences in either the duration of response or the survival term. The major adverse effects and abnormal laboratory test values included alopecia, nausea and vomiting, general fatigue, anorexia and leukopenia, with no difference in incidence between the groups. Moon face, genital hemorrhage and body weight increase, which are thought to be caused by MPA, were found in both groups without a significant difference in incidence. The results of this study revealed no differences in effectiveness or safety between MPA 1,200 mg and 600 mg, suggesting that MPA for combined use with CAF is fully effective at a dose of 600 mg.

Cranionavigator combining a high-speed drill and a navigation system for skull base surgery--technical note

Drilling of the skull base bone without damaging the important inside structures and with the correct orientation is very difficult even with the help of the anatomical landmarks. Monitoring of the location and direction of the drill tip and indications of the removed part of the bone during the drilling procedure enhances safety and achieves less invasive neurosurgery. We have developed a novel cranionavigator by combining a high-speed drill with a neurosurgical navigation system. To reduce the positional error to less than 1.5 mm, the position sensor (magnetic field sensor) must be attached 5 cm from the metallic fan portion of the drill and the sensor kept at least 10 cm away from the operating microscope. Simulation studies with the cranionavigator using two dried skulls and three cadaver heads were performed before clinical application. Clinically, this surgical instrument was used in four patients with the skull base tumor. The cranionavigator helped to safely drill the skull base bone in a shorter time by dynamic and real-time display of the precise operating site and extent of bone drilling on the preoperative computed tomography scans or magnetic resonance images. The cranionavigator is a very helpful instrument for skull base surgery in the hands of neurosurgeons with extensive expertise and anatomical knowledge.

Percutaneous transluminal angioplasty and stent placement for subclavian and brachiocephalic artery stenosis in aortitis syndrome

A 43-year-old man with progressive right common carotid, subclavian artery, and brachiocephalic artery stenoses due to aortitis syndrome is presented. The patient's right common carotid artery had been treated by percutaneous transluminal angioplasty (PTA) four times previously, but it was finally occluded. The right subclavian artery was treated by PTA once, which resulted in restenosis. The stenosis extended to the brachiocephalic artery. For this patient, PTA followed by stent placement was performed for the right subclavian and brachiocephalic artery stenosis. Because arterial stenosis is progressive in cases of aortitis syndrome, simple PTA alone does not appear to be sufficient for treatment. We suggest that PTA followed by stent placement may be an alternative treatment for recurrent stenosis in aortitis syndrome.

Platelet-derived endothelial cell growth factor/thymidine phosphorylase concentrations differ in small cell and non-small cell lung cancer

OBJECTIVE

Platelet-derived endothelial cell growth factor (PD-ECGF)/thymidine phosphorylase (TP) has been implicated in cancer angiogenesis, which is critical for tumor growth and metastasis. We investigated the relationship between the tissue concentration of PD-ECGF/TP and the clinicopathologic status in human lung cancer.

METHODS

The concentrations of PD-ECGF/TP in the tumor extracts of 139 primary human lung carcinomas were measured by using a highly specific and sensitive enzyme-linked immunosorbent assay.

RESULTS

PD-ECGF/TP was detected in the extracts from 137 of 139 specimens at concentrations that ranged from 2.0 to 169.5 U/mg protein. PD-ECGF/TP concentrations in patients with adenocarcinoma (n = 73) and squamous cell carcinoma (n = 49) were (mean +/- SD) 30.7+/-22.9 U/mg protein (range, 7.6 to 169.5 U/mg protein) and 32.0+/-19.8 U/mg protein (range, 8.0 to 84.4 U/mg protein), respectively. No significant difference was found in the PD-ECGF/TP concentration between these two types of non-small cell lung cancer (NSCLC). However, a > 8-fold lower mean concentration of PD-ECGF/TP was found in tissue extracts from small cell lung cancer (SCLC) (n = 17; 3.65+/-2.01 U/mg protein, ranging from undetectable to 6.1 U/mg protein) than in those from adenocarcinomas (p = 0.00005) or squamous cell carcinomas (p < 0.00001).

CONCLUSIONS

The striking difference in PD-ECGF/TP concentrations between SCLC and NSCLC suggests that these two types of lung cancer use alternative pathways for angiogenesis. The present study suggests that inhibitors of PD-ECGF/TP, which have been recently developed and are under laboratory investigation to test their effectiveness as treatments for various types of cancer, may not be effective against SCLC.

Down regulation of peroxisome proliferator-activated receptorgamma expression by inflammatory cytokines and its reversal by thiazolidinediones

AIMS/HYPOTHESIS

Previous studies show that inflammatory cytokines play a part in the development of insulin resistance. Thiazolidinediones were developed as insulin-sensitizing drugs and are ligands for the peroxisome proliferator-activated receptory (PPARgamma). We hypothesized that the anti-diabetic mechanism of thiazolidinediones depends on the quantity of PPARgamma in the insulin resistant state in which inflammatory cytokines play a part.

METHODS

We isolated rat PPARgamma1 and gamma2 cDNAs and examined effects of various cytokines and thiazolidinediones on PPARgamma mRNA expression in rat mature adipocytes.

RESULTS

Various inflammatory cytokines, such as tumour necrosis factor-alpha (TNF-alpha), interleukin-1alpha (IL-1alpha), IL-1beta, IL-6 and leukaemia inhibitory factor decreased PPARgamma mRNA expression. In addition, hydrogen peroxide, lysophosphatidylcholine or phorbol 12-myristate 13-acetate also decreased the expression of PPARgamma. The suppression of PPARgamma mRNA expression caused by 10 nmol/l of TNF-alpha was reversed 60% and 55% by treatment with 10(-4) mol/l of troglitazone and 10(-4) mol/l of pioglitazone, respectively. The suppression of glucose transporter 4 mRNA expression caused by TNF-alpha was also reversed by thiazolidinediones. Associated with the change of PPARgamma mRNA expression, troglitazone improved glucose uptake suppressed by TNF-alpha.

CONCLUSION/INTERPRETATION

Our study suggests that inflammatory cytokines could be factors that regulate PPARgamma expression for possible modulation of insulin resistance. In addition, we speculate that the regulation of PPARgamma mRNA expression may contribute to the anti-diabetic mechanism of thiazolidinediones.

The prognostic significance of amplification and overexpression of c-met and c-erb B-2 in human gastric carcinomas

BACKGROUND

The c-met and the c-erb B-2 protooncogenes belong to a family of tyrosine kinase growth factor receptors. Abnormalities of these oncogenes and protein products have been reported in several cancers. The authors investigated the correlation between clinical factors and amplification or overexpression of the c-met and/or c-erb B-2 gene in Japanese patients with gastric carcinoma patients, with a focus on prognostic significance.

METHODS

Amplification and overexpression of c-met and c-erb B-2 were investigated retrospectively in 128 gastric carcinoma patients by using immunohistochemistry and Southern blot hybridization. Survival analysis was performed with the Kaplan-Meier test, and the log rank test was used for statistical analysis.

RESULTS

Overexpression of c-met and c-erb B-2 was observed in 46.1% and 16.4% of gastric carcinoma cases, respectively. Gene amplification of c-met and c-erb B-2 was detected in 10.2% and 11.7% of gastric carcinoma cases, respectively. Amplification and overexpression of c-met were correlated significantly with depth of tumor invasion and lymph node metastasis, whereas amplification and overexpression of c-erb B-2 were correlated significantly with histologic type. The survival rate of patients with amplification and/or overexpression of c-met or c-erb B-2 was significantly poorer than that of patients with no amplification or overexpression. Multivariate analysis revealed that c-met overexpression and lymph node metastasis were independent prognostic factors.

CONCLUSIONS

These data suggest that overexpression and/or gene amplification of c-met and c-erb B-2 may be prognostic factors in gastric carcinoma.

The prognostic significance of amplification and overexpression of c-met and c-erb B-2 in human gastric carcinomas

BACKGROUND

The c-met and the c-erb B-2 protooncogenes belong to a family of tyrosine kinase growth factor receptors. Abnormalities of these oncogenes and protein products have been reported in several cancers. The authors investigated the correlation between clinical factors and amplification or overexpression of the c-met and/or c-erb B-2 gene in Japanese patients with gastric carcinoma patients, with a focus on prognostic significance.

METHODS

Amplification and overexpression of c-met and c-erb B-2 were investigated retrospectively in 128 gastric carcinoma patients by using immunohistochemistry and Southern blot hybridization. Survival analysis was performed with the Kaplan-Meier test, and the log rank test was used for statistical analysis.

RESULTS

Overexpression of c-met and c-erb B-2 was observed in 46.1% and 16.4% of gastric carcinoma cases, respectively. Gene amplification of c-met and c-erb B-2 was detected in 10.2% and 11.7% of gastric carcinoma cases, respectively. Amplification and overexpression of c-met were correlated significantly with depth of tumor invasion and lymph node metastasis, whereas amplification and overexpression of c-erb B-2 were correlated significantly with histologic type. The survival rate of patients with amplification and/or overexpression of c-met or c-erb B-2 was significantly poorer than that of patients with no amplification or overexpression. Multivariate analysis revealed that c-met overexpression and lymph node metastasis were independent prognostic factors.

CONCLUSIONS

These data suggest that overexpression and/or gene amplification of c-met and c-erb B-2 may be prognostic factors in gastric carcinoma.

The prognostic significance of amplification and overexpression of c-met and c-erb B-2 in human gastric carcinomas

BACKGROUND

The c-met and the c-erb B-2 protooncogenes belong to a family of tyrosine kinase growth factor receptors. Abnormalities of these oncogenes and protein products have been reported in several cancers. The authors investigated the correlation between clinical factors and amplification or overexpression of the c-met and/or c-erb B-2 gene in Japanese patients with gastric carcinoma patients, with a focus on prognostic significance.

METHODS

Amplification and overexpression of c-met and c-erb B-2 were investigated retrospectively in 128 gastric carcinoma patients by using immunohistochemistry and Southern blot hybridization. Survival analysis was performed with the Kaplan-Meier test, and the log rank test was used for statistical analysis.

RESULTS

Overexpression of c-met and c-erb B-2 was observed in 46.1% and 16.4% of gastric carcinoma cases, respectively. Gene amplification of c-met and c-erb B-2 was detected in 10.2% and 11.7% of gastric carcinoma cases, respectively. Amplification and overexpression of c-met were correlated significantly with depth of tumor invasion and lymph node metastasis, whereas amplification and overexpression of c-erb B-2 were correlated significantly with histologic type. The survival rate of patients with amplification and/or overexpression of c-met or c-erb B-2 was significantly poorer than that of patients with no amplification or overexpression. Multivariate analysis revealed that c-met overexpression and lymph node metastasis were independent prognostic factors.

CONCLUSIONS

These data suggest that overexpression and/or gene amplification of c-met and c-erb B-2 may be prognostic factors in gastric carcinoma.

The prognostic significance of amplification and overexpression of c-met and c-erb B-2 in human gastric carcinomas

BACKGROUND

The c-met and the c-erb B-2 protooncogenes belong to a family of tyrosine kinase growth factor receptors. Abnormalities of these oncogenes and protein products have been reported in several cancers. The authors investigated the correlation between clinical factors and amplification or overexpression of the c-met and/or c-erb B-2 gene in Japanese patients with gastric carcinoma patients, with a focus on prognostic significance.

METHODS

Amplification and overexpression of c-met and c-erb B-2 were investigated retrospectively in 128 gastric carcinoma patients by using immunohistochemistry and Southern blot hybridization. Survival analysis was performed with the Kaplan-Meier test, and the log rank test was used for statistical analysis.

RESULTS

Overexpression of c-met and c-erb B-2 was observed in 46.1% and 16.4% of gastric carcinoma cases, respectively. Gene amplification of c-met and c-erb B-2 was detected in 10.2% and 11.7% of gastric carcinoma cases, respectively. Amplification and overexpression of c-met were correlated significantly with depth of tumor invasion and lymph node metastasis, whereas amplification and overexpression of c-erb B-2 were correlated significantly with histologic type. The survival rate of patients with amplification and/or overexpression of c-met or c-erb B-2 was significantly poorer than that of patients with no amplification or overexpression. Multivariate analysis revealed that c-met overexpression and lymph node metastasis were independent prognostic factors.

CONCLUSIONS

These data suggest that overexpression and/or gene amplification of c-met and c-erb B-2 may be prognostic factors in gastric carcinoma.

The prognostic significance of amplification and overexpression of c-met and c-erb B-2 in human gastric carcinomas

BACKGROUND

The c-met and the c-erb B-2 protooncogenes belong to a family of tyrosine kinase growth factor receptors. Abnormalities of these oncogenes and protein products have been reported in several cancers. The authors investigated the correlation between clinical factors and amplification or overexpression of the c-met and/or c-erb B-2 gene in Japanese patients with gastric carcinoma patients, with a focus on prognostic significance.

METHODS

Amplification and overexpression of c-met and c-erb B-2 were investigated retrospectively in 128 gastric carcinoma patients by using immunohistochemistry and Southern blot hybridization. Survival analysis was performed with the Kaplan-Meier test, and the log rank test was used for statistical analysis.

RESULTS

Overexpression of c-met and c-erb B-2 was observed in 46.1% and 16.4% of gastric carcinoma cases, respectively. Gene amplification of c-met and c-erb B-2 was detected in 10.2% and 11.7% of gastric carcinoma cases, respectively. Amplification and overexpression of c-met were correlated significantly with depth of tumor invasion and lymph node metastasis, whereas amplification and overexpression of c-erb B-2 were correlated significantly with histologic type. The survival rate of patients with amplification and/or overexpression of c-met or c-erb B-2 was significantly poorer than that of patients with no amplification or overexpression. Multivariate analysis revealed that c-met overexpression and lymph node metastasis were independent prognostic factors.

CONCLUSIONS

These data suggest that overexpression and/or gene amplification of c-met and c-erb B-2 may be prognostic factors in gastric carcinoma.

Cervical lymph nodes play the role of regional lymph nodes in brain tumour immunity in rats

Recent physiological and anatomical studies have demonstrated that a major fraction of brain interstitial and cerebrospinal fluid drains into cervical lymph nodes (CLN) in a number of experimental animals. To investigate the role of CLN in brain tumour immunity, temporal profiles of MHC class II molecule expression and T lymphocyte subsets in brain tumours, CLN and other lymphoid tissues were analysed by immunocytochemistry. A total of 64 Wistar rats weighing 250 g were used. Two weeks after the transplantation of C6 glioma cells (10(6) cells/1 microl) into a rat brain, expression of MHC class II molecules was induced in the brain and all systemic lymphoid tissues examined. However, the subsequent appearance of CD4 or CD8 positive cells was strictly confined to CLN, and coincided with the infiltration of such cells into the brain tumour 2 weeks after transplantation. In the group of animals in which cervical lymphadenectomy was followed by intracerebral transplantation of C6 glioma cells, infiltration of CD4 or CD8 positive cells into the brain tumour was delayed until 3 weeks after the transplantation, and the production of such cells was by the spleen. These results suggest that CLN act as regional lymph nodes in brain tumour immunity.

Ets-1 positively regulates expression of urokinase-type plasminogen activator (uPA) and invasiveness of astrocytic tumors

Acquisition of invasive/metastatic potential through protease expression is an essential event in tumor progression. Urokinase-type plasminogen activator (uPA) is often expressed in human tumors including astrocytic tumors. To elucidate the possible regulation mechanism of uPA gene expression in astrocytic tumors, quantitative RT-PCR was performed to monitor the gene expression of uPA and the transcription factor Ets-1. Expression of uPA and Ets-1 genes was up-regulated in astrocytic tumors, but was not detected in normal brain. Expression levels of uPA correlated with those of Ets-1, and also with the degree of malignancy of the tumors. Glioma cell lines U251, U87, and T98G also expressed both uPA and Ets-1 genes. Expression of a dominant negative mutant of Ets-1, which competitively inhibits Ets-1 function, abolished uPA expression in U251 cells. Parental U251 cells showed invasive growth in 3-dimensional collagen gel, however, cells expressing dominant negative Ets-1 failed to grow invasively in the collagen gel. Treatment of U251 cells with the uPA inhibitor aprotinin also inhibited spreading of cells into collagen gel. These results suggest that Ets-1 plays an essential role in regulation of uPA gene expression, which in turn contributes to the invasive growth of astrocytic tumors.

Endovascular embolization of unruptured vertebral dissection using Guglielmi electrolytically detachable coils: case report

We present a patient with unruptured vertebral dissection whose angiograph showed further enlargement of the aneurysm, after a transient reduction in the size of the fusiform dilatation. Tolerance of parent artery occlusion was first confirmed by a balloon occlusion test. Both proximal and distal portions of the vertebral artery, including the dissected site, were occluded using Guglielmi electrolytically detachable coils; there were no complications. No new symptoms occurred during a 9-month follow-up period. For cases presenting with angiographic aneurysmal enlargement, embolization of the lesion using electrolytically detachable coils may be effective.

Postictal blockade of ischemic hippocampal neuronal death in primates using selective cathepsin inhibitors

This paper is to study the participation of cathepsin in ischemic neuronal death of the monkey hippocampal cornu ammonis (CA) 1 sector and also to clarify whether its selective inhibitor epoxysuccinyl peptides such as CA-074 and E-64c can inhibit the neuronal death or not. In the preceding reports, we demonstrated mu-calpain activation and subsequent rupturing of the lysosomal membrane of postischemic CA1 neurons and also increase of enzyme activity of cathepsins B and L in monkeys undergoing a complete 20-min whole brain ischemia. Here, morphological, immunohistochemical and enzymatical analyses were performed to examine the efficacy of two selective cathepsin inhibitors in the postictal blockade of delayed neuronal death in the monkey hippocampus. Both inhibitors could significantly decrease enzyme activities of cathepsins B and L in all hippocampal sectors. When CA-074 was intravenously administered immediately after the ischemic insult, approximately 67% of CA1 neurons were saved from delayed neuronal death on day 5 after ischemia. In contrast, when E-64c was similarly administered, approximately 84% of CA1 neurons were saved from delayed neuronal death on day 5. The surviving neurons showed mild central chromatolysis and negligible immunoreactivity for cathepsins B and L. These observations indicate that the use of cathepsin inhibitors may become novel strategy for prevention of ischemic delayed neuronal death in the primate hippocampus.

Expression and tissue localization of membrane-type 1, 2, and 3 matrix metalloproteinases in human astrocytic tumors

Three different membrane-type matrix metalloproteinases (MT1-, MT2-, and MT3-MMPs) are known to activate in vitro the zymogen of MMP-2 (pro-MMP-2, progelatinase A), which is one of the key MMPs in invasion and metastasis of various cancers. In the present study, we have examined production and activation of pro-MMP-2, expression of MT1-, MT2-, and MT3-MMPs and their correlation with pro-MMP-2 activation, and localization of MMP-2, MT1-MMP, and MT2-MMP in human astrocytic tumors. The sandwich enzyme immunoassay demonstrates that the production levels of pro-MMP-2 in the anaplastic astrocytomas and glioblastomas are significantly higher than that in the low-grade astrocytomas (P<0.05 and P<0.01, respectively), metastatic brain tumors (P<0.05), or normal brains (P<0.01). Gelatin zymography indicates that the pro-MMP-2 activation ratio is significantly higher in the glioblastomas than in other astrocytic tumors (P<0.01), metastatic brain tumors (P<0.01), and normal brains (P<0.01). The quantitative reverse transcription polymerase chain reaction analyses demonstrate that MT1-MMP and MT2-MMP are expressed predominantly in glioblastoma tissues (17/17 and 12/17 cases, respectively), and their expression levels increase significantly as tumor grade increases. MT3-MMP is detectable in both astrocytic tumor and normal brain tissues, but the mean expression level is approximately 50-fold lower compared with that of MT1-MMP and MT2-MMP in the glioblastomas. The activation ratio of pro-MMP-2 correlates directly with the expression levels of MT1-MMP and MT2-MMP but not MT3-MMP. In situ hybridization indicates that neoplastic astrocytes express MT1-MMP and MT2-MMP in the glioblastoma tissues (5/5 cases and 5/5 cases, respectively). Immunohistochemically, MT1-MMP and MT2-MMP are localized to the neoplastic astrocytes in glioblastoma samples (17/17 cases and 12/17 cases, respectively), which are also positive for MMP-2. In situ zymography shows gelatinolytic activity in the glioblastoma tissues but not in the normal brain tissues. These results suggest that both MT1-MMP and MT2-MMP play a key role in the activation of pro-MMP-2 in the human malignant astrocytic tumors and that the gelatinolytic activity is involved in the astrocytic tumor invasion.

Olivary degeneration after intracranial haemorrhage or trauma: follow-up MRI

We studied serial MRI appearances of transneuronal degeneration in the inferior olives, retrospectively analysing follow-up images of five patients, three with head injury and two with brain stem haemorrhage. We performed 13 MRI studies 4 days to 2 years 7 months after the accident. All but one of the patients exhibited bilateral olivary high signal on T2-weighted images. The interval between causal event and appearance of olivary changes was 2-4 months, images 4 days to 1.5 months after the accidents revealing no changes. Olivary enlargement was observed in four patients 2-4 months after ictus.

Real-time 3-D model-based navigation system for endoscopic paranasal sinus surgery

This paper presents a three-dimensional (3-D)-model-based navigation system for endoscopic sinus surgery treating paranasal sinusitis. Endoscopic surgery is becoming more common because of its low invasiveness. Its problem with disorientation, however, is one of the toughest barriers for the novice and may lead even an expert to commit serious surgical errors, e.g., causing cerebrospinal fluid (CSF) leakage or blinding the patient. To prevent such complications and optimize training, our system aids in navigation by showing a single perspective view of the patient and the endoscope models. This virtual endoscope has a viewing cone with a simulated light to indicate the viewing direction and visual field in real-time. The system's three clipping planes automatically follow the endoscope and help keep the surgeon aware of the endoscope's actual position. An experiment comparing the system to conventional navigation using a triplanar display showed that the perspective view was referenced very frequently, giving a positive impressions, while the triplanar display was almost completely ignored, apparently because it was too difficult to interpret immediately.