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Biomedical subjects

J Kuratsu

Publications and source records attributed to J Kuratsu.

At least 55 records · Page 3Linked to original sources
PubMed1999

Intraspinal osteogenic meningioma: report of a case.

Dense calcification and psammomatous bodies are common in spinal meningioma, but are rarely reported in osteogenic meningioma. We present a 73-year-old woman with an extramedullary, intradural tumor located at the T5 vertebra. The tumor showed mixed intensity and heterogeneous enhancement on the T1-weighted image and hypointensity on the T2-weighted image, and was situated near the spinal nerve root. The tumor's initial symptom was myelopathy, as is usual with spinal meningioma. We successfully removed the tumor under microscopy and found it to be separated from the vertebral column by the epidural space. The symptoms and signs improved gradually after the operation. Because the pathologic examination revealed areas of lamellar bone with bone marrow in the transitional meningioma, and because these were not related to the psammomatous bodies, osteogenic meningioma was diagnosed. Metaplasia of arachnoid cells is considered to be the putative etiology of osteogenic meningioma.

Aged↗
PubMed1999

Prognostic significance of the MIB-1 labeling index for patient with craniopharyngioma.

Proliferative activity of 17 craniopharyngiomas were determined using an immunohistochemical method with monoclonal antibody MIB-1. A considerable variation of the MIB-1 labeling indices was found between the different tumors with a minimum of 0.4% and a maximum of 32.5% (median, 10.84%). The mean MIB-1 labeling index (LI) for 4 craniopharyngiomas that showed no evidence of recurrence (n=4) was 3.4 +/- 2.3%. This was significantly lower than that for craniopharyngiomas that showed recurrence and regrowth (13.2 +/- 7.7%) (n=13), based on the initial resected tumors. Statistical analysis reveal that craniopharyngiomas with an MIB-1 LI of 7% or more have a significantly high tendency for recurrence and regrowth during clinical course. Our data suggest that a MIB-1 LI greater than 7% may be a useful predictor of regrowth/recurrence of craniopharyngiomas and may be useful for planning of adjuvant therapy.

Adolescent↗
PubMed1998

Kainic acid-induced perirhinal cortical seizures in rats.

Seizures induced in rats by kainic acid microinjection into the perirhinal cortex were studied electrophysiologically and behaviorally and compared with known features of seizures following kainic acid injection into the amygdala. Unlike amygdalar seizures, perirhinal cortical seizures did not generalize to become limbic seizures but rather spread to sensorimotor cortex to become manifest as motor seizures. Perirhinal cortical seizures also required larger kainic acid doses for provocation and were briefer.

Amygdala↗
PubMed1998

Expression of CD44 adhesion molecules in intracranial germinomas.

Adhesion molecules play a role in tumor growth, invasiveness, and the metastatic process. The expression of CD44 adhesion molecules in 11 intracranial germinoma specimens was investigated using anti-CD44 monoclonal antibody and immunohistochemical methods. In six of 11 specimens studied, CD44 antibodies were bound to the membrane of tumor cells; in five of six specimens, CD44 antigen was also present in the cytoplasm of tumor cells. The only three patients who showed CD44-positive expression in tumor cells, lymphocytes, and extracellular matrix (ECM) exhibited either cerebrospinal fluid dissemination or multiple tumors at different locations. In all 11 specimens, no expression of CD44 in normal glial cells or capillary endothelium was detected. According to the authors' findings, the expression of CD44 in intracranial germinomas is similar to that of gonadal seminomas. Analysis of the results further suggests the possibility that the expression of CD44 in intracranial germinoma tumor cells, lymphocytes, and ECM may contribute to tumor cell migration, adhesion to cerebrospinal fluid dissemination, and/or multiple tumor locations.

Journal Article↗
PubMed1998

Pineal germinomas with granulomatous inflammation. Report of two cases and review of the literature.

The authors report on two cases of pineal germinomas with granulomatous inflammation (granulomatous germinomas). Macroscopically, both tumors were relatively hard and grayish in color. Histological examination revealed a germinoma with multinucleated giant cells and Schaumann bodies in one case, and a germinoma with the background of acellular fibrillated matrix in the other. On immunohistochemical analysis, the granulomatous germinomas were shown to contain many macrophages, T- and B-lymphocytes, and glial fibrillary acid protein-positive cells infiltrating the specimens, compared to nongranulomatous germinomas. Analysis of Masson's trichrome staining tests showed that large areas of the granulomatous germinomas were occupied by a collagenous component; this was not the case in cases of nongranulomatous germinomas. Analysis of monoclonal anti-human Ki-67 results showed that the granulomatous germinomas had a lower score than nongranulomatous germinomas (p < 0.05, unpaired t-test), indicating that germinomas with granulomatous inflammation may have a better prognosis.

Journal Article↗
PubMed1998

Identification of a human homolog of the Drosophila neuralized gene within the 10q25.1 malignant astrocytoma deletion region.

The loss of chromosome 10 is the most frequent genetic alteration found in malignant astrocytomas. In particular, the long arm of chromosome 10 was previously reported to have two or more common deletion regions where tumor suppressor genes may be located. In this study, we performed deletion mapping of 44 malignant astrocytomas using 12 microsatellite markers on chromosome 10q and demonstrated that the minimal common region of loss of heterozygosity (LOH) was present between D10S192 and D10S566 localized at 10q25.1. Subsequently, we have identified a novel gene, termed h-neu, within the region frequently deleted and found that h-neu encodes a protein with strong homology to the Drosophila neuralized (D-neu) protein. Northern blot and RT-PCR analyses revealed that h-neu mRNA was expressed at very low levels in human malignant astrocytoma tissues and the majority of glioma cell lines examined, while normal brains expressed h-neu transcript. Furthermore, DNA sequencing analysis of the h-neu transcript revealed one of the glioma cell lines, U251MG, had a single nucleotide substitution which resulted in an amino acid change from glycine (GGC) to serine (AGC) at codon 253. The D-neu gene is known to serve a critical function in neurogenesis in Drosophila, and loss-of-function mutations produce hyperplasia of primitive neuronal cells. These observations led us to hypothesize that h-neu gene plays a role in determination of cell fate in the human central nervous system and may act as a tumor suppressor whose inactivation could be associated with malignant progression of astrocytic tumors.

Amino Acid Sequence↗
PubMed1998

Intradermal injection of monocyte chemoattractant protein-1 induces emigration and differentiation of blood monocytes in rat skin.

BACKGROUND: Monocyte chemoattractant protein-1 (MCP-1) is a potent chemoattractant for blood monocytes in vitro. Recent studies in MCP-1-transgenic mice revealed that the local production of MCP-1 caused monocyte infiltration. However, the kinetics of monocyte infiltration after the production of MCP-1 or the amount of MCP-1 necessary for monocyte recruitment are not known. METHODS: We purified recombinant rat MCP-1 expressed in COS-7 cells, and injected it into rat skin. The infiltrating cells were examined by immunohistochemistry and ultrastructural peroxidase cytochemistry. RESULTS: Rat recombinant MCP-1 had a molecular mass of approximately 30 kD and exhibited the peak monocyte chemotactic activity at 10(-9) M. One microgram of MCP-1 caused intra- and extravascular accumulation of mononuclear cells 3 h after injection. The cells were ED1+, indicating they were blood monocytes. The infiltration of mononuclear cells peaked at 12-24 h, and most of them were TRPM-3+ and ED3+, characteristic to exudate macrophages. None of the cells expressed ED2 or Ki-M2R antigens, markers for resident macrophages, until 3 days after injection. There was no uptake of [3H]thymidine by the infiltrating cells. Ultrastructural peroxidase cytochemistry confirmed that the infiltrating cells were monocytes and exudate macrophages. The number of OX8+ lymphocytes also peaked at 12 h, consisting of approximately 9% of the total infiltrating cells. CONCLUSION: These results indicate that MCP-1 attracts blood monocytes as early as 3 h and the infiltrating monocytes differentiate into exudate macrophages in loco. However, this effect was transient and the infiltration of monocytes did not result in tissue damage.

Animals↗
PubMed1998

Primary malignant lymphoma of the brain in childhood.

A 5-year-old boy presented with a 1-year history of frontal headache and nausea. Neurological examination showed left abducens nerve palsy, left facial nerve palsy, Bruns' nystagmus, and wide-based gait. Neuroimaging demonstrated a lesion with moderate linear enhancement in the left cerebellar hemisphere. He underwent stereotactic needle biopsy. The histological diagnosis was well-differentiated small lymphocytic type of malignant lymphoma. Following the biopsy, the patient underwent radiotherapy (whole brain 30 Gy, local 20 Gy). He has been in good condition for more than 5 years. The long-term survival is attributable to the absence of aggressiveness and the good response to radiation of this subtype of malignant lymphoma.

Brain Neoplasms↗
PubMed1997

Intracranial intraparenchymal schwannoma: report of three cases.

Intracranial intraparenchymal schwannomas are rare. We report three patients with an intracranial intraparenchymal schwannoma and discuss the clinical and neuroradiological aspects of this particular tumour. The patients were a 21-year-old male, a 64-year-old female and a 17-year-old male. The tumours were located in cerebrum in two patients and the cerebellum in one patient. Computerized tomography (CT) scans demonstrated a slightly high density area with homogeneous enhancement by contrast medium. Magnetic resonance imaging (MRI) showed slightly low signal intensity on the T1-weighted image, high or mixed signal intensity on the T2-weighted image and homogeneous enhancement by gadolinium diethylene triamine penta-acetic acid (Gd-DTPA). Radiological studies revealed cystic components in 2 of the 3 patients. All tumours were firm, well-demarcated, and completely removed. The diagnosis of schwannoma was derived from histological and immunohistochemical studies in all 3 cases; 2 cases were also examined by electron microscopy.

Adolescent↗
PubMed1997

Dynamic MRI of meningiomas and schwannomas: is differential diagnosis possible?

We studied 23 patients with meningiomas and 14 with schwannomas using dynamic spin-echo (TR/TE 200/15 ms) MRI. Histologically the meningiomas were classified according to the 1993 WHO classification. Serial images were obtained every 30s for 210s after rapid injection of gadopentetate dimeglumine (0.1 mmol/kg). The contrast-enhancement ratio (CER) was divided into three patterns; a sharp rise with a peak within 60 s (A), a relatively rapid increase with a peak between 60 and 210s (B), a slow increase without a peak (C). The patterns were correlated with the histology of the tumors. The signal intensities of the tumours on T2-weighted images were also analyzed and correlated with the dynamic patterns. Meningiomas had more varied dynamic patterns than schwannomas. Almost half of the meningiomas showed pattern A, and one third pattern C. Of six meningiothelial meningiomas showed pattern A; all schwannomas and fibrous meningiomas showed pattern C. Various patterns were observed in transitional meningiomas. Of the 8 meningiomas showing pattern C, only one gave high signal on T2-weighted images, and could not be differentiated from the schwannomas. Thus, one third of meningiomas could not be differentiated from schwannomas by the dynamic contrast enhancement alone. However, when this was combined with the signal intensity on T2-weighted images, most meningiomas could be differentiated from schwannomas.

Brain↗
PubMed1997

Epidemiological study of primary intracranial tumours in elderly people.

The incidence of primary intracranial tumours in a well defined population of persons older than 70 years (elderly) who resided in Kumamoto prefecture was examined. During the period from 1989 to 1995, primary intracranial tumours were diagnosed in 271 elderly people; of these, 155 (57.2%) tumours were confirmed microscopically. In a mean population of 216,000 people over the age of 70 years, this yields an average annual incidence rate of 18.1 cases/100,000 population/year. The incidence was lower in men (15.2/100,000 population) than women (20.3/100,000 population). The age specific incidence/100,000/year was 23.2 for the 70-74 year age group, 18.1 for the 75-79 year age group, 15.1 for the 80-84 year age group, and 7.6 for persons older than 85 years. The most common tumours were meningiomas (50.6%), followed by malignant gliomas (13.3%), pituitary adenomas (12.9%), schwannomas (6.6%), malignant lymphomas (3.7%), and benign astrocytomas (3.7%).

Age Distribution↗
PubMed1997

Cerebellar mutism after posterior fossa surgery--two case reports.

Two adults (aged 71 and 74 years) developed cerebellar mutism after posterior fossa surgery for a mass lesion in the superior cerebellar hemisphere or upper vermis. Histological examination showed one was a hemangioblastoma, the other a metastatic brain tumor. The tumors were totally removed via the occipital transtentorial approach. Both patients developed mutism on the 2nd postoperative day, which persisted for 3-4 weeks and was followed within 2-4 months by cerebellar dysarthria. Thereafter, their condition improved. Transient cerebellar mutism usually occurs in pediatric patients after the removal of a mass lesion in the upper vermis. Cerebellar mutism in adults is rare. The predominance of cerebellar mutism in children may be attributable to the predilection for vermian tumor and their tendency to experience personality and behavioral changes after posterior fossa surgery.

Aged↗
PubMed1997

Treatment of cancer using pulsed electric field in combination with chemotherapeutic agents or genes.

Electroporation is a standard laboratory technique originally developed for in vitro transfer of molecules into cells. It involves application of electrical pulses ranging from micro- to milliseconds that create transient pores in the cell membrane allowing intracellular access of exogenous molecules. This technique has been successfully applied to regress tumors in animal models by combining electroporation with chemotherapeutic agents--a process known as electrochemotherapy (ECT) which substantially enhance cytotoxicity of some antineoplastic agents. Recently ECT has moved into clinical arena and patients with cutaneous tumors and head and neck cancers have been treated very effectively with ECT. Parallel to ECT, a technique has also been developed which makes it possible to inject plasmid DNA and combine it with in vivo electroporation--electro--genetherapy (EGT)--to deliver in a highly efficient manner both marker and functional genes into target tissue and achieve gene expression. Thus, in vivo electroporation is contributing to the development of a new strategy for cancer treatment with both drugs and genes.

Animals↗
PubMed1996

Intrathecal chemotherapy with 1,3-bis(2-chloroethyl)-1-nitrosourea encapsulated into hybrid liposomes for meningeal gliomatosis: an experimental study.

1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU), one of the chloroethyl nitrosoureas, is effective against malignant glioma. To develop its use in intrathecal chemotherapy, we encapsulated BCNU in hybrid liposomes composed of dimyristoylphosphatidylcholine and micellar surfactants (Tween 20) and dissolved it in artificial cerebrospinal fluid (lipo-BCNU). We then studied the toxicity of hybrid liposomes and cellular proliferation inhibition of lipo-BCNU in vitro. We found that 3 mM hybrid liposomes did not affect the viability of human endothelial cells and that lipo-BCNU inhibited the proliferation of human glioma cell lines U-105MG, U-251MG, and U-373MG, and rat glioma cell lines C6 and 9L in a concentration-dependent fashion. Wistar rats that were administered lipo-BCNU intracisternally showed no weight loss, neurological symptoms, or histological changes of the brain and spinal cord. A Wistar rat model of meningeal gliomatosis was established by intracisternal inoculation of 0.1 ml cell suspension containing 1 x 10(6) or 5 x 10(6) viable C6 glioma cells. Two days after inoculation, lipo-BCNU (BCNU, 2.5 mg/kg) was administered intracisternally. When 1 x 10(6) glioma cells were inoculated (experiments 1 and 2), the median survival times were 24.5 and 26 days in the control groups and 32 and 45 days in the lipo-BCNU-treated groups. respectively. When 5 x 10(6) glioma cells were inoculated (experiments 3-6), the median survival times were 17-29.5 days in the control groups and 23-44 days in the treated groups, respectively. Significantly prolonged survival was obtained in three of six experimental groups. After the administration of 1 ml lipo-BCNU (BCNU, 4.67 mM) or 1 ml BCNU solubilized with 5% dextrose/water (BCNU, 4.67 mM) into the cisterna magna of dogs, the cisterna magna cerebrospinal fluid was sampled, and the BCNU concentrations were assayed by high-performance liquid chromatography. The half-life of the lipo-BCNU was longer than that of BCNU solubilized with 5% dextrose/water. These results suggest that the intrathecal administration of lipo-BCNU may be possible for the treatment of meningeal gliomatosis.

Animals↗
PubMed1996

Expression of tissue factor correlates with grade of malignancy in human glioma.

BACKGROUND: Tissue factor (TF), a cell surface receptor of factor VII/VIIa, was initially recognized as an initiator of the extrinsic coagulation pathway. TF has recently been found to be expressed highly in certain types of malignant tumors. In addition, TF belongs to the interferon receptor family and is one of the immediate early genes, suggesting that TF may participate in the regulation of cell growth. However, the correlation between the expression of TF and cell growth is still unclear. METHODS: Expression of TF in 6 glioma cell lines and 44 glioma surgical specimens was studied by Northern blot analysis, Western blot analysis, immunohistochemistry, and in situ hybridization. RESULTS: Northern blot analysis showed that glioma cells expressed minor novel transcripts of 3.3 kb and 1.6 kb, in addition to the transcripts of 2.2 kb and 3.1 kb that were previously reported. Western blot analysis revealed that the level of TF protein did not correlate with that of TF transcripts. Although immunohistochemical analysis of surgical specimens showed that all gliomas were positive for TF, it was interesting that 1 of 10 benign gliomas (10%) was positive for TF (malignancy Grade I-II), 13 of 14 anaplastic astrocytomas (86%) (malignancy grade III) and 19 of 20 glioblastomas (95%) (malignancy grade IV) were moderately or strongly positive for TF. In situ hybridization showed the expression of TF mRNA in glioma cells. CONCLUSIONS: TF is expressed in glioma and the level of expression correlates with the histologic grade of malignancy.

Astrocytoma↗
PubMed1996

High-efficiency in vivo gene transfer using intraarterial plasmid DNA injection following in vivo electroporation.

A novel method for high-efficiency and region- controlled in vivo gene transfer was developed by combining in vivo electroporation and intraarterial plasmid DNA injection. A mammalian expression plasmid for the Escherichia coli lacZ gene (driven with a SV40 early promoter) was injected into the internal carotid artery of rats whose brain tumors (from prior inoculation) had been electroporated between two electrodes. The lacZ gene was efficiently transferred and expressed in the tumor cell 3 days after plasmid injection. However, neither any gene transfers nor any elevated lacZ activity was detected in tissues outside the electrodes. The plasmid was not transferred without electroporation. Human monocyte chemoattractant protein-1 cDNA was also transferred by this method, and its long-lasting (3 weeks) expression was confirmed by using the Epstein-Barr virus episomal replicon system. The expressed monocyte chemoattractant protein-1 protein was functional, as evident by the presence of a large number of monocytes in tumor tissue. This method, electrogene therapy, which does not require viral genes or particles, allows genes to be transferred and expressed in desired organs or tissues, and it may lead to the development of a new type of highly effective gene therapy.

Animals↗