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Biomedical subjects

Jun Yoshida

Publications and source records attributed to Jun Yoshida.

At least 73 records · Page 4Linked to original sources
PubMed2003

Effective induction of antiglioma cytotoxic T cells by coadministration of interferon-beta gene vector and dendritic cells.

As type I interferons (IFNs) enhance the stimulatory activity of dendritic cells (DCs), we hypothesized that transfection of glioma cells with the IFN-beta gene in the presence of DCs would provide particularly effective antitumor activity by both facilitating apoptosis of glioma cells and presenting the resulting glioma antigens to T cell by DCs, thereby inducing specific T-cell responses against glioma cells. A mouse glioma cell line 203G was first transfected with cDNA encoding IFN-beta using cationic liposomes, then cocultured with syngeneic bone marrow-derived DCs and naïve splenic T cells. The 203G cells were almost completely killed following 96-hour coculture with DCs and T cells, and strong tumor-specific cytotoxic T-lymphocyte (CTL) activity accompanied by high level interleukin (IL)-12 and IFN-gamma production was observed in culture. In addition, omission of either IFN-beta gene delivery, DCs or T cells from the coculture completely abrogated the induction of the CTL activity, suggesting that the combination of these components was required to elicit an optimal effect. On the basis of these in vitro data, syngeneic animals bearing subcutaneous 203G tumors received intratumoral injections of IFN-beta gene and DCs. Suppression of the tumor growth by this combinational therapy was superior to treatment with DC or IFN-beta gene solely. This combination may constitute a new therapeutic strategy to induce potent antiglioma immune responses.

Animals↗
PubMed2003

Growth inhibition of subcutaneous mouse melanoma and induction of natural killer cells by liposome-mediated interferon-beta gene therapy.

In this study we investigated the antitumour effect and mechanism of action of cationic liposome-mediated murine interferon-beta (IFNbeta) gene therapy in mouse B16F1 melanoma cells in vitro and in vivo. Murine IFNbeta gene transfer by cationic liposome resulted in substantial growth inhibition of B16F1 melanoma cells in culture when compared with phosphate buffered saline or recombinant murine IFNbeta treatment, or lacZ control gene transfer. Use of video-enhanced contrast-differential interference contrast (VEC-DIC) microscopy revealed that liposomes containing the murine IFNbeta gene [lip(pSV2muIFNbeta)], but not recombinant murine IFNbeta, induced dramatic morphological changes that characterize apoptosis, including bleb formation, shrinkage of cells, nuclear condensation and 'ballooning', in approximately 30% of the cells treated. Intratumoral administration of lip(pSV2muIFNbeta) resulted in a 5.5-fold reduction in the mean volume of subcutaneous melanoma lesions in syngeneic mice 15 days after treatment and eradicated the tumour in 18% of the mice treated. Immunocytochemical analysis demonstrated that a larger number of natural killer (NK) cells infiltrated the tumour following lip(pSV2muIFNbeta) treatment than in controls. In vivo depletion of NK cells using the anti-asialoGM1 antibody reduced the efficacy of lip(pSV2muIFNbeta) treatment. Taken together, our data suggest that cationic liposome-mediated IFNbeta gene therapy could be effective against melanoma by directly inducing cell death and stimulating NK cells.

Animals↗
PubMed2003

Surgical management and outcome of tuberculous atlantoaxial dislocation: a 15-year experience.

OBJECTIVE: Tuberculous atlantoaxial dislocation is a rare disease entity. However, tuberculosis continues to be endemic in developing countries. Its earliest clinical presentation may be nonspecific, and delay in diagnosis may lead to irreversible neurological deficit. The management of tuberculous atlantoaxial dislocation includes ventral cervicomedullary decompression, occipitocervical arthrodesis, and administration of antituberculous medications. METHODS: Eighteen patients with tuberculous atlantoaxial dislocation who presented with neck pain and/or occipital headache, restriction of neck movement, difficulty swallowing, and signs of myelopathy were studied. Four patients had evidence of associated pulmonary tuberculosis. Plain x-rays of the cervical spine, computed tomographic scans, and magnetic resonance images were obtained in all patients for diagnosis and to assess the degree of dislocation and cervicomedullary compression. Simultaneous anterior neural decompression, via a transcervical retropharyngeal approach, and posterior arthrodesis were performed on all patients while they remained under anesthesia. Antituberculous chemotherapy was continued for 18 months. RESULTS: Histopathological analysis of excised tissue was consistent with tuberculosis in all patients. However, Ziehl-Neelsen staining for acid-fast bacilli was positive in two cases, and culture for Mycobacterium tuberculosis was negative in all patients. Patients with severe myelopathy experienced marked improvement. One patient died of fulminant resistant tuberculous meningitis. CONCLUSION: The transcervical retropharyngeal approach to the craniovertebral junction provides direct access to the lesion and avoids the potential bacterial contamination of the oral and pharyngeal cavity. It also prevents the development of persistent fistulae. Posterior stabilization should be performed directly after anterior neural decompression, while the patient remains under anesthesia, to prevent neurological deterioration before subsequent posterior fixation. This technique also is helpful for early mobilization of patients. The aim of surgical treatment should be to obtain biopsy tissue and to perform radical excision of epidural granulation tissue/abscess and infected bone using microsurgical technique. Antituberculous medication must be continued for 18 months with four drug regimens, and continuous monitoring of drug toxicity should be performed throughout the course of treatment.

Adolescent↗
PubMed2003

Caspase activation in neuronal and glial apoptosis following spinal cord injury in mice.

The involvement of caspases in apoptosis after spinal cord injury (SCI) was investigated in adult mouse spinal cord after contusion. Sections of spinal cord were processed for staining 7 days after SCI with the fluorescent dye Hoechst 33342, terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end-labeling (TUNEL), and immunostaining with an antibody (CM1) recognizing activated caspase-3. Caspase-3- and caspase-8-like enzyme activities were measured colorimetrically at 8 hours to 7 days after SCI using the specific substrates Asp-Glu-Val-Asp-p-nitroanilide and Ile-Glu-Thr-Asp-p-nitroanilide, respectively. Hoechst 33342 staining showed small, bright areas in fragmented nuclei. Double labeling with TUNEL plus immunostaining with cell type-specific markers identified TUNEL-positive neurons stained by anti-neuronal nuclear protein/neurons antibody, and TUNEL-positive oligodendrocytes stained by anti-cyclic nucleotide 3'-phosphohydrolase antibody. Double labeling with CM1 and cell-type specific markers similarly identified CM1-positive neurons and oligodendrocytes. Caspase-8-like enzyme activity was increased significantly on days 3 and 7 (p < 0.01), whereas caspase-3-like activity increased on day 7 (p < 0.01). Intraventricular injection of a nonspecific tetrapeptide caspase inhibitor or a specific tetrapeptide inhibitor of caspase-3 just after SCI reduced enzyme activity at 7 days. Apoptotic cells were identified with TUNEL staining in both neurons and oligodendrocytes in mice after SCI, which also showed activated caspase-3. Increased caspase-3- and caspase-8-like activity was detected in the injured spinal cord on days 3 and 7. Caspase protease activities may be involved in delayed neuronal and glial apoptosis after SCI.

Animals↗
PubMed2003

Schwannoma in the crural cistern removed without permanent functional deficits--case report.

A 33-year-old male presented with a rare intracranial oculomotor schwannoma not associated with neurofibromatosis manifesting as an 8-month history of right oculomotor nerve paresis. Neuroimaging examinations revealed a 4-cm mass in the right crural cistern. The tumor was totally removed. The right oculomotor nerve paresis resolved 7 months after surgery. Removal of the oculomotor or trochlear schwannoma usually results in parent nerve paresis, but subcapsular tumor resection in our case probably allowed complete recovery of the nerve function.

Adult↗
PubMed2003

Morphological assessment of the development of multinucleated giant cells in glioma by using mitosis-specific phosphorylated antibodies.

OBJECT: The nature and origin of multinucleated giant cells in glioma have not been made clear. To investigate the phosphorylation of intermediate filaments, the authors studied multinucleated giant cells in vitro and in vivo by using mitosis-specific phosphorylated antibodies. METHODS: Cultured human glioma cells were immunostained with monoclonal antibodies (mAbs) 4A4, KT13, and TM71, which recognized the phosphorylation of vimentin at Ser55, glial fibrillary acidic protein at Serl3, and vimentin at Ser71, respectively. Subsequently, the nature of multinucleated giant cells was investigated using laser scanning confocal microscopy. In addition, paraffin-embedded tissue sections obtained in three patients with giant cell glioblastoma were also investigated. Multinucleated giant cells were immunoreacted with the mAb 4A4 and not with KT13 and TM71 in vitro and in vivo. In addition, the authors obtained these results in multinucleated giant cells under natural conditions, without drug treatments. CONCLUSIONS: Findings in this investigation indicated that multinucleated giant cells are those remaining in mitosis between metaphase and telophase, undergoing neither fusion nor degeneration.

Antibodies, Neoplasm↗
PubMed2003

Age at symptom onset and long-term survival in patients with neurofibromatosis Type 2.

OBJECT: Neurofibromatosis Type 2 (NF2) is an intractable disorder predisposing to multiple, recurrent tumors of the central nervous system (CNS). To clarify the survival rate and characteristics that predict poor survival, we retrospectively reviewed clinical data in cases of NF2. METHODS: From among 283 patients with neurofibromatosis who had been registered in a nationwide study in Japan between 1986 and 1987, 74 patients with bilateral vestibular schwannomas were analyzed. The mean duration of follow up after diagnosis was 121 months (range 2-287 months). Results of a Kaplan-Meier product-limit analysis indicated that overall 5-, 10-, and 20-year patient survival rates following diagnosis of NF2 were 85, 67, and 38%, respectively. Early onset of the initial symptom significantly compromised survival; 5-, 10-, and 20-year survival rates in patients with symptom onset at an age younger than 25 years were 80, 60, and 28%, respectively, whereas in patients with symptom onset at an age of 25 years or older the rates were 100, 87, and 62%, respectively. Patients with small vestibular schwannomas at diagnosis (< 2 cm in diameter) had better rates of survival. Other variables such as sex, additional tumors in the CNS, or dermal abnormalities did not significantly affect survival. CONCLUSIONS: This first report of long-term follow-up results concerning the survival of patients with NF2 indicates an adverse effect of early symptom onset.

Adult↗
PubMed2003

Transarticular screw fixation in the middle and lower cervical spine. Technical note.

Although atlantoaxial transarticular screw fixation is technically demanding and there is a significant risk of vertebral artery (VA) injury, transarticular screw insertion in the middle and lower cervical spine is simple and can be performed safely with the aid of lateral fluoroscopic guidance. The authors describe the surgical techniques and outcome of transarticular screw fixation in the middle and lower cervical spine. Transarticular screw insertion into C2-3 or caudal cervical joints was performed from the articular pillar, directing the screw anterocaudally to penetrate the facet joint and the anterior cortex of the articular pillar, parallel to the sagittal plane. Because the VA and the nerve roots are anterior to the articular pillar at these levels, the screw can be placed safely with the assistance of lateral fluoroscopic guidance. Twenty-five patients ranging in age from 15 to 84 years underwent transarticular screw fixation, with a total of 81 screws. The transarticular screw was used as an anchor screw in combination with posterior cervical instrumentation in 19 patients and for facet screw fixation itself in six patients. Screw placement was successful and uncomplicated in all cases. The follow-up period ranged from 3 months to 5 years. No instance of screw backout or loosening was identified radiographically; fusion was achieved in all patients. Biomechanical strength is maintained by penetrating four cortical layers. When performed appropriately, this method is safe and reliable and deserves more widespread use.

Adolescent↗
PubMed2003

Significant antitumoral activity of cationic multilamellar liposomes containing human IFN-beta gene against human renal cell carcinoma.

PURPOSE: Immunotherapy is the most effective treatment against metastatic renal cell carcinoma (RCC). However, the response rate is approximately 15%. More effective therapy is, therefore, needed for patients with metastatic RCC. We then examined the antitumor effect of cationic multilamellar liposome containing human IFN-beta (huIFN-beta) gene (IAB-1) against RCC. EXPERIMENTAL DESIGN: Concentrations of huIFN-beta protein were measured by ELISA. The cytotoxicity of IAB-1 against human RCC (NC65, ACHN, and freshly isolated RCC cells), prostate and bladder cancer cell lines, and renal proximal tubule endothelial cells (RPTEC5899) was examined by the colorimetric method using tetrazolium salt. Apoptosis was assessed by the acridine-orange staining. For in vivo study, we used NC65 cells inoculated into severe combined immunodeficiency mouse. RESULTS: The RCC cells treated with IAB-1 secreted significant amounts of huIFN-beta protein continuously. Drastic in vitro cytotoxic effect of IAB-1 against RCC was observed. In contrast, treatment with 1000 IU/ml recombinant huIFN-beta protein resulted in weak cytotoxicity. The cytotoxic effect against prostate and bladder cancer cell lines was less than that against RCC. Furthermore, no significant cytotoxicity was observed in RPTEC5899 cells. Apoptosis was observed in the cells treated with IAB-1, but recombinant huIFN-beta failed to induce apoptosis. The size of NC65 tumors transfected with IAB-1 in mice was significantly smaller than that receiving injection of empty liposome or recombinant huIFN-beta protein. CONCLUSION: These findings indicate that IAB-1 may have an antitumor activity against human RCC by inducing apoptosis, suggesting its potential clinical application for gene therapy against RCC.

Acridine Orange↗
PubMed2003

[Brain tumors].

Brain tumors generally arise as the culmination of a multistep process that involves a variety of genetic abnormalities. Theoretically, replacement of abnormal genes with normal genes is essential to brain tumor treatment. However, it is very difficult to replace all damaged genes. Currently, most clinical protocols for gene therapy in brain tumors include transfer of a gene which can induce tumor cells to die or which can enhance the environment to generate a systemic immune response against the tumor. The former strategy includes suicide gene therapies, tumor suppressor gene therapy and oncolytic virus therapy. The latter adopts immunogene therapy. In this report, we also focus on other gene therapies, such as therapies to control the cell cycle or apoptosis, and promote antiangiogenesis. Gene therapy is generally accepted to be rather safe in recent years. In fact, the current single-gene therapies for brain tumor are limited and probably restricted to a few tumors. Several agents with different mechanisms of action would be necessary to kill heterogenously mixed tumor cells. Further molecular techniques and basic studies may overcome the malignancy of cancers.

Adenoviridae↗
PubMed2003

Endovascular treatment strategy for direct carotid-cavernous fistulas resulting from rupture of intracavernous carotid aneurysms.

BACKGROUND AND PURPOSE: Reported treatments and outcomes in aneurysmal carotid-cavernous fistulas (CCFs) have been admixed with those of cases considered to be symptomatic of intracavernous aneurysm. However, aneurysmal CCFs have clinical features distinct from those of dural arteriovenous fistulas, and treatment strategies similar to those of traumatic CCF are required. We evaluated our experience in placing detachable balloons in the management of spontaneous CCFs due to rupture of an intracavernous aneurysm. METHODS: Six patients (one man, five women; mean age, 64.7 years) were treated for spontaneous direct CCF at our institution between 1995 and 2001. All patients presented with sudden ocular symptoms including exophthalmos, conjunctival injection, chemosis, and ocular motor palsies. Detachable latex balloons were used as the embolic material in five patients, and in one patient the cavernous sinus was packed transarterially with coils. RESULTS: All six patients were successfully treated by means of transarterial embolization, and symptoms improved within a week. CONCLUSION: Although other techniques using a transvenous approach and/or detachable coils may also be useful, embolization with detachable balloons should be a safe and effective method to immediately occlude the fistula.

Aged↗
PubMed2003

Cell death of human oral squamous cell carcinoma cell line induced by herpes simplex virus thymidine kinase gene and ganciclovir.

Suicide gene therapy combining herpes simplex virus thymidine kinase gene (HSVtk) and ganciclovir (GCV) is one strategy for the treatment of head and neck squamous cell carcinoma (HNSCC). The purpose of this study is to determine the mechanism of cell death that occurs in suicide gene therapy using HSVtk and GCV and to assess the safety of that therapy. The human oral squamous cell carcinoma cell line SAS was treated with adenovirus vector containing HSVtk gene (AdHSVtk) and GCV in vitro. Morphological changes including chromatin condensation, cell shrinkage, blebbing of cell membrane, and ballooning formations were observed. Changes in the localization of phospholipids in the cell membrane were also observed. The results of flow cytometry showed a maximum of about 65% of cells in the early phase of apoptosis. In addition, DNA fragmentation was investigated using the TUNEL method in vivo. Nude mice (BALB/c AJD(-nu-), aged 4 weeks) were implanted with SAS and treated with AdHSVtk and GCV. Tumor sections were then observed. The treatment group was confirmed to have DNA fragmentation-positive cells. These results suggest that suicide gene therapy using AdHSVtk and GCV led to apoptosis of the oral squamous cell carcinoma cell line.

Adenoviridae↗
PubMed2002

Repeated cationic multilamellar liposome-mediated gene transfer enhanced transduction efficiency against murine melanoma cell lines.

We investigated whether repeated cationic multilamellar liposome-mediated gene transfers enhanced the transduction efficiency against murine melanoma cell lines and experimental subcutaneous melanoma. In the former, the murine melanoma cell line, B16F10, was transfected by our original cationic multilamellar liposomes containing pVLacZ, which express beta-galactosidase in eukaryotic cells. Cells were exposed to the liposomes in a single, double, or triple procedure during the cell logarithmic proliferative period. We then evaluated the transduction efficiency by X-gal staining and beta-galactosidase assay. The number of positive cells and level of beta-galactosidase activity were significantly increased by repeated exposures compared with a single one. Cells transfected by the fluorescently labeled cationic liposome containing pEGFP-C1 showed both an increased uptake of liposomes and an increased number of EGFP expression cells following repeated exposures. In the latter, murine subcutaneous melanomas, which were made by transplantation of B16F10 in C57BL6 mice, were transfected by same liposomes. Subcutaneous melanomas were exposed to the liposomes in a single, double, or triple procedure. We then evaluated the transduction efficiency by the beta-galactosidase assay. The level of beta-galactosidase activity was significantly increased by repeated exposures compared with a single one. The results indicate that repeated exposures to the liposomes enhanced the transduction efficiency toward murine melanoma cells and experimental subcutaneous melanoma, and may provide a basis for the repeated-exposure protocol for human trials.

Animals↗
PubMed2002

Effective solitary hyperthermia treatment of malignant glioma using stick type CMC-magnetite. In vivo study.

Various kinds of hyperthermic treatment for malignant glioma had been inhibited due to both their incomplete feverish action and strict cooling effect of the brain. The author shows an effective results of hyperthermia for the treatment of malignant glioma in an in vivo study using stick type carboxymethylcellulose (CMC)-magnetite, a newly manufactured magnetite-product. A stick type CMC-magnetite, containing magnetite particles, was inserted into the T-9 glioma in the rat brain stereotactically, and the rats were exposed to an alternative magnetic field (AMF). The application time of AMF, which measured 88.9 kHz and 380 Oe, was 30 min a day. The rats were divided into three groups: three AMF applications (group I), one AMF application (group II) and no application but only injection of CMC-magnetite (control). As a result, the mean survival in days of these three groups measured 44.2+/-10.9 (group I), 17.0+/-1.5 (group II) and 14.4+/-1.5 (control). This investigation showed both significant effectiveness in attacking malignant glioma and significant prolonging of the survival time in rats. It is also a characteristic feature of the magnetite particles to spread through the tumor diffusely after three applications of AMF. This feature seemed to be one of the main factors that caused greater hyperthermic effect on glioma in this study. This method of hyperthermic treatment could be a useful strategy in the treatment of malignant glioma.

Animals↗
PubMed2002

Reduction of alpha-galactosyl xenoantigen by expression of endo-beta-galactosidase C in pig endothelial cells.

BACKGROUND: Elimination of the Galalpha1-3Galbeta1-4GlcNAc (alphaGal) epitope has been considered to be essential for successful pig-to-human xenotransplantation but, unfortunately, has not been achieved. Endo-beta-galactosidase C (EndoGalC) is an endoglycosidase which cleaves the Galbeta1-4GlcNAc linkage in the alphaGal epitope and digests out the Galalpha1-3Gal disaccharide. Because of its potent activity in physiological pH conditions, EndoGalC can remove alphaGal epitopes expressed on the cell surface of pig erythrocytes and vascular endothelial cells almost completely. In vivo or ex vivo administration of EndoGalC successfully reduced alphaGal expression in pig kidneys to an undetectable level, but alphaGal epitopes soon reappeared. Gene expression of EndoGalC in pig cells was attempted to solve this problem. As the terminal alphaGal is transferred in the trans-Golgi network by alpha-1,3-galactosyltransferase (alpha1,3GT), colocalization of the EndoGalC gene with the alpha1,3GT gene was expected to be one of the most reliable ways to eliminate the alphaGal epitope. METHODS AND RESULTS: The sequence of pig alpha1,3GT, including the cytoplasmic tail, transmembrane domain and stem region, was ligated upstream of EndoGalC, and the conjugated gene was expressed in pig aortic endothelial cells and COS7 cells. Following the introduction of the gene, the alphaGal epitope on pig aortic endothelial cells was effectively reduced. Transfection studies in COS7 cells using EndoGalC combined with alpha1,3GT showed that the expressed EndoGalC was localized not only inside, but also outside, the cells. The expression of EndoGalC conjugated with a murine immunoglobulin (Igkappa)-chain signal sequence also showed a similar effect. CONCLUSIONS: These results suggest the effectiveness of gene transfer with EndoGalC into pig endothelial cells, and strongly encourage us to produce transgenic animals with the expressed enzyme.

Animals↗
PubMed2002

Cationic liposomes conjugation to recombinant adenoviral vectors containing herpes simplex virus thymidine kinase gene followed by ganciclovir treatment reduces viral antigenicity and maintains antitumor activity in mouse experimental glioma models.

Gene therapy using adenoviral (Ad) vector containing herpes simplex virus thymidine kinase (AxCAHSV-tk) followed by the administration of ganciclovir (GCV) has been a promising therapy for cancer including malignant gliomas. However, there remain numerous problems to overcome, such as the high immunogenicity and toxicity of Ad vector. To optimize the therapy, we investigated whether a conjugation of our original cationic liposomes and Ad vectors reduces viral antigenicity and maintains the antitumor activity in mouse experimental (subcutaneous and intracranial) glioma models. Our original liposomes consist of N-(alpha-trimethylammonioacetyl)-didodecyl-D-glutamate chloride, dilauroyl phosphatidylcholine, and dioleoyl phosphatidyl-ethanolamine in a molar ratio of 1:2:2. AxCAHSV-tk and GCV showed a remarkable inhibition of experimental glioma growth. The growth-inhibitory effect decreased in mice previously immunized with another Ad vector (AxCALacZ). In contrast, the conjugation of AxCAHSV-tk and liposomes did not diminish the growth-inhibitory effect. Furthermore, the conjugation reduced antigenicity for Ad vector in vivo. These findings suggest that suicide gene therapy, using a conjugation of AxCAHSV-tk and our liposomes, is a feasible approach for human cancer gene therapy, especially malignant gliomas.

Adenoviridae↗
PubMed2002

Phosphorylation of neuronal nitric oxide synthase at Ser847 by CaM-KII in the hippocampus of rat brain after transient forebrain ischemia.

The authors previously demonstrated that Ca2+/calmodulin (CaM)-dependent protein kinase IIalpha (CaM-KIIalpha) can phosphorylate neuronal nitric oxide synthase (nNOS) at Ser847 and attenuate NOS activity in neuronal cells. In the present study, they established that forebrain ischemia causes an increase in the phosphorylation of nNOS at Ser847 in the hippocampus. This nNOS phosphorylation appeared to be catalyzed by CaM-KII: (1) it correlated with the autophosphorylation of CaM-KIIalpha; (2) it was blocked by the CaM-KII inhibitor, KN-93; and (3) nNOS and CaM-KIIalpha were found to coexist in the hippocampus. Examination of the spatial relation between nNOS and CaM-KIIalpha in the brain revealed coexistence in the hippocampus but not in the cortex during reperfusion, with a concomitant increase in autophosphorylation of CaM-KIIalpha. The phosphorylation of nNOS at Ser847 probably takes place in nonpyramidal hippocampal neurons, which increased after 30 minutes of reperfusion in the hippocampus, whereas no significant increase was detected in the cortex. An intraventricular injection of KN-93 significantly decreased the phosphorylation of nNOS in the hippocampus. These results point to CaM-KII as a protein kinase, which by its colocalization may attenuate the activity of nNOS through its Ser847 phosphorylation, and may thus contribute to promotion of tolerance to postischemic damage in hippocampal neurons.

Animals↗