Expression of cell cycle regulator p27Kip1 is correlated with survival of patients with astrocytoma.

p27Kip1 is a cyclin-dependent kinase inhibitor that negatively regulates cell proliferation by mediating cell cycle arrest in G1. This study was undertaken to assess the prognostic value of p27Kip1 for astrocytomas. Tissue samples from 130 astrocytomas (WHO grade 1, 5 cases; grade 2, 23 cases; grade 3, 64 cases; grade 4, 38 cases), including 92 primary and 38 recurrent tumors, were examined immunohistochemically for Ki-67 and p27Kip1 expression.

Effect of intracarotid infusion of etoposide: modification of the permeability of the blood-brain barrier and the blood-tumor barrier in rat brain tumor model.

The effect of intracarotid infusion of etoposide on the permeability of the blood-brain barrier (BBB) and brain-tumor barrier (BTB) was investigated using a model of rats injected with C6 glioma cells. Fifty four glioma-bearing rats were divided into 3 groups and treated with 0, 3, or 15 mg/kg of etoposide infused into the internal carotid artery. BBB or BTB permeability was evaluated qualitatively by the leakage of Evans blue (6 animals in each group) or quantitatively by the diffusion of carboplatin [cis-diammine (1,1-cyclobutane-dicarboxylato) platinum(II); CBDCA] (12 animals in each group) into the normal brain or the tumor tissue.

"Kissing" bilateral large carotid-ophthalmic aneurysms. A case report.

A case of unruptured bilateral large carotid-ophthalmic aneurysms, which appear to be adjoining and "kissing" each other when visualized by three-dimensional computed tomographic angiography (3-D CTA), is reported. Although bilateral carotid-ophthalmic aneurysms are not rare, bilateral large ones are quite rare, and direct imaging of "kissing aneurysms" of this portion has not been reported. Since 3-D CTA is becoming a useful tool for the diagnosis of cerebral aneurysms, we propose that these and similar bilateral large carotid-ophthalmic aneurysms are good candidates for the term "kissing aneurysms".

[Clinical results of supratentorial astrocytoma grade II].

At present, there is no consensus concerning the treatment of low-grade gliomas. The authors conducted a retrospective review of surgically treated, histologically verified cases of supratentorial astrocytomas of grade II to evaluate the results of current treatment methods. Thirty-seven patients, 23 males and 14 females, treated from April, 1977 through March, 1997 were analyzed.

Complete nucleotide sequences of cDNAs encoding long chain alpha-neurotoxins from sea krait, Laticauda semifasciata.

This paper presents the nucleotide sequences of the cDNAs encoding two long chain alpha-neurotoxins from Laticauda semifasciata venom gland. The deduced amino acid sequences are Ls-III and its iso-neurotoxin.

Primary brain tumors in children under age 3 years.

During the period from 1966 to 1996 the authors analyzed the clinicopathological characteristics of 46 cases of histologically verified primary brain tumors with symptomatic onset during the first 3 years of life. The patient group included 27 males and 19 females. There were 14 patients during the first year, 13 during the second year, and 19 during the third year.

[A clinical evaluation of combination therapy with radiation, MCNU, carboplatin and IFN-beta or with radiation, MCNU, carboplatin, etoposide and IFN-beta for malignant gliomas].

In this study, we examined the clinical course and prognosis of 32 patients with malignant glioma (17 patients with anaplastic astrocytoma, 15 patients with glioblastoma) treated with the MIC regimen (radiation, MCNU, carboplatin and IFN-beta) or MICE regimen (radiation, MCNU, carboplatin, etoposide and IFN-beta). Ten patients were treated with the MIC regimen and 22 patients with the MICE regimen. The patients treated with the MIC and MICE regimens exhibited no significant difference in clinical background factors.

[Primary malignant lymphoma in the central nervous system treated with high dose methotrexate (MTX)-CHOP (M-CHOP)].

From December 1995 to July 1997, six patients with primary malignant lymphoma in the central nervous system were treated with 2 to 5 cycles of the M-CHOP regimen (methotrexate 3 g/m2 on day 1, cyclophosphamide 750 mg/m2 on day 1, doxorubicin 40 mg/m2 on day 1, vincristine 1.4 mg/m2 on day 1, and predonisolone 60 mg on day 1 to 14: folic acid was given 3 hours after methotrexate at 10 mg/m2 every 3 hours for 9 doses intravenously). Five patients achieved complete remission (CR) and one experienced partial remission (PR).

[Gene transduction for experimental brain tumors using recombinant adenovirus vector].

Recent advances in molecular biology have permitted significant progress toward the treatment of malignant brain tumors using gene transduction methods. Adenovirus vectors have recently been shown to transduce genes successfully into brain tumor cells both in vitro and in vivo. We have investigated the feasibility of gene transduction for brain tumors using adenovirus vectors.

[Extradural temporopolar approach for giant pituitary adenomas invading the cavernous sinus and parasellar regions].

Objective: An extradural temporopolar approach has recently been used in the treatment of the parasellar, infrachiasmatic, or intracavernous regions. In this approach, the temporal (superficial) dural layer is separated from the deep layer (inner cavernous membrane) to expose the cavernous sinus extradurally. We report our experiences with 5 cases in which a giant pituitary adenoma invading the cavernous sinus and parasellar regions was resected via the extradural temporopolar approach.

Malignant cerebellar astrocytoma developing 15 years after radiation therapy for a medulloblastoma.

A case of malignant cerebellar astrocytoma occurring 15 years after the radiation therapy for a medulloblastoma is reported. The tumor developed at the same site of irradiation after a sufficient latent period and was completely different from medulloblastoma in its histology. This tumor fulfilled the criteria of radiation-induced neoplasm.

Proliferative potential and apoptosis in rat glioma cell lines after hyperthermia.

The proliferative potential of cultured rat glioma cells (C6 and 9L) was evaluated after hyperthermia using immunohistochemical staining with bromodeoxyuridine (BrdU) and Ki-67 monoclonal antibodies. Apoptosis was assessed by in situ end-labeling of deoxyribonucleic acid breaks. Both BrdU and Ki-67 labeling indexes decreased with increasing hyperthermia time.

Molecular evolution of snake toxins: is the functional diversity of snake toxins associated with a mechanism of accelerated evolution?

Recent studies revealed that animal toxins with unrelated biological functions often possess a similar architecture. To tentatively understand the evolutionary mechanisms that may govern this principle of functional prodigality associated with a structural economy, two complementary approaches were considered. One of them consisted of investigating the rates of mutations that occur in cDNAs and/or genes that encode a variety of toxins with the same fold.

Regression of experimental brain tumors with 6-thioxanthine and Escherichia coli gpt gene therapy.

The identification of transgenes with antitumor activity is critical to the development of gene therapy of cancer. Retrovirus-mediated transfer of the Escherichia coli gpt gene into rat C6 glioma cells without subsequent selection still inhibited the proliferation of this mixed polyclonal population upon addition of the prodrug, 6-thioxanthine, with an ID50 of 4.1 microM, whereas parental C6 cells were not affected at a concentration of 500 microM.

Induction of resistance to etoposide and adriamycin in a human glioma cell line treated with antisense oligodeoxynucleotide complementary to the messenger ribonucleic acid of deoxyribonucleic acid topoisomerase II alpha.

Acquisition of resistance to anticancer agents is a serious problem for cancer chemotherapy. The present study analyzed the relationship between expression of the alpha isoform of deoxyribonucleic acid (DNA) topoisomerase II (topo II alpha) and chemosensitivity to topo II inhibitors by modulating the level of topo II alpha expression. A phosphorothioate analogue of an 18-nucleotide oligomer which is complementary to the translation initiation site of the human topo II alpha messenger ribonucleic acid sequence was used to suppress the expression of topo II alpha in a human glioma cell line (U373MG).

[Stereotactic brachytherapy for clival chordoma].

There has recently been interest in the use of high-dose radiation with methods such as radiosurgery and brachytherapy for skull base tumors. Brachytherapy is believed to be effective for clival chordomas, but technical difficulties exist in stereotactic insertion of catheters into the clivus. We assessed the usefulness following improvement of implantation techniques in three patients with clival chordomas.

Direct clip obliteration of a ruptured giant aneurysm of the posterior communicating artery: case report.

Objective And Importance: A review of the literature documents that giant posterior communicating artery (PCoA) aneurysms are rare. To our knowledge, this report is the first to describe a ruptured giant aneurysm arising from a PCoA that was successfully clipped.

Clinical Presentation: A 27-year-old man had a left oculomotor palsy and then suffered a subarachnoid hemorrhage.

Accumulation of wild-type p53 in astrocytomas is associated with increased p21 expression.

Approximately one quarter of human astrocytomas show immunohistochemical positivity for p53 protein but lack p53 gene mutations, which could reflect either an accumulation of wild-type p53 protein or an inadequate sensitivity of mutation detection. Since wild-type p53 up-regulates p21 expression, increased p21 expression in those astrocytomas with p53 accumulation in the absence of mutations would argue that the protein was wild type in these tumors. We therefore compared p21 expression with p53 gene and protein status in 48 primary human astrocytomas.

[Clinical study of primary central nervous system lymphoma: the role of chemotherapy].

We conducted a retrospective study of 32 patients with histologically confirmed primary central nervous system lymphoma treated in our institute between 1971 and 1995 with an emphasis on the role of chemotherapy. Thirty of the 32 patients underwent tumor resection, whereas 2 patients had biopsies only. Twenty-eight patients received adjuvant therapy, 9 of whom received radiation therapy alone, 2 received chemotherapy alone, and 17 received both radiation therapy and chemotherapy.

Malignant astrocytomas with homozygous CDKN2/p16 gene deletions have higher Ki-67 proliferation indices.

p16 is involved in a cell-cycle regulatory cascade that includes cyclin-dependent kinase 4 (cdk4), cyclin D1 and pRb. Alterations of each of these components have been described in primary human glioblastoma multiforme (GBM) or GBM cell lines, and alterations of the individual components of this pathway appear inversely correlated with one another. While this suggests that disruption of any individual component has similar oncogenic effects, homozygous deletions of the CDKN2/p16 gene are the most common genetic alteration.

Escherichia coli gpt gene sensitizes rat glioma cells to killing by 6-thioxanthine or 6-thioguanine.

Genes that encode enzymes that convert inactive "prodrugs" into anticancer metabolites may be therapeutically useful against brain tumors. Unlike other genes tested to date in brain tumor models, the Escherichia coli gpt gene is unique in that it not only sensitizes cells to the prodrug 6-thioxanthine (6TX) but also encodes resistance to a different regimen (mycophenolic acid, xanthine, and hypoxanthine), thus providing a means to select for gpt-positive cells. In the present study, rat C6 glioma cells were infected with a retrovirus vector that transduces this gene.

Selective fallopian tube catheterisation in female infertility: clinical results and absorbed radiation dose.

Clinical results of fluoroscopic fallopian tube catheterisation and absorbed radiation doses during the procedure were evaluated in 30 infertility patients with unilateral or bilateral tubal obstruction documented on hysterosalpingography. The staged technique consisted of contrast injection through an intrauterine catheter with a vacuum cup device, ostial salpingography with the wedged catheter, and selective salpingography with a coaxial microcatheter. Of 45 fallopian tubes examined, 35 (78%) were demonstrated by the procedure, and at least one tube was newly demonstrated in 26 patients (87%).

Diffusible cytotoxic metabolites contribute to the in vitro bystander effect associated with the cyclophosphamide/cytochrome P450 2B1 cancer gene therapy paradigm.

Tumor cells become sensitive to the inert prodrug cyclophosphamide (CPA) after transfer of the gene encoding cytochrome P450 2B1. This enzyme activates CPA into 4-hydroxycyclophosphamide, which ultimately degrades into acrolein and phosphoramide mustard, the anticancer and DNA-alkylating metabolite. It is imperative that any prodrug-activating gene therapy strategy against cancer possess the capacity to affect the proliferation of tumor cells even when they do not express the transgene (bystander effect), because current methodologies cannot achieve gene transduction in all tumor cells.