Biomedical subjects

J Yoshida

Publications and source records attributed to J Yoshida.

At least 307 records · Page 17Linked to original sources

PubMed1993

An experimental model for anaplastic astrocytomas and glioblastoma using adult F344 rats and N-methyl-N-nitrosourea.

An experimental model for induction of gliomas corresponding to human anaplastic astrocytomas and glioblastomas is reported. Eleven week old F344 and ACI rats were given 100 or 200 p.p.m. N-methyl-N-nitrosourea (MNU) solution as their drinking water for 42 weeks. Gliomas were induced at very high incidences (82.5-92.5%) in each group. Induced gliomas showed apparent evidence of morphologic malignancy by an analysis based on diagnostic criteria of human astrocytomas. All of the gliomas from the killed animals were classified histologically into subtypes according to the classification scheme used in the diagnosis of human gliomas. The majority of macrotumors more than 1 mm in diameter in both strains were diagnosed as anaplastic astrocytomas and glioblastomas. Immunohistochemically, tumor cells in these tumors were almost negative for glial fibrillary acidic protein, while ultrastructurally neoplastic astrocytes contained glial filaments. A strain difference was observed in the ratio of histological subtypes of macrotumors. In F344 rats, astrocytic tumors diagnosed as anaplastic astrocytomas and glioblastomas of an astrocytic type formed the majority, whereas glioblastomas of mixed oligo-astrocytic type predominated in ACI rats. The results indicate that MNU-administration to adult F344 rats may provide a suitable experimental model for gliomas which occur in adult humans.

Animals↗

PubMed1993

[Study on the experimental ulcerative colitis model induced by dextran sulfate sodium in rats: estimation of mucosal erosions by the alcian blue-staining method].

We have developed a new method that is applicable for a macroscopic and objective evaluation of erosion in the large intestine in the experimental ulcerative colitis model induced by dextran sulfate sodium (DSS) in rats. The large intestine (without cecum) fixed in 10% neutral buffered formalin solution for more than one week was opened and stained with 1% alcian blue solution. The mucosal surface was stained in light and shade-blue. Histopathological examination revealed that the dark blue area on the mucosal surface had no epithelia and that the connective tissues in the lamina propria were stained with alcian blue. Salazosulfapyridine at 15 and 50 mg/kg twice a day inhibited the erosion area (dark blue area) by 29.6% and 50.2%, respectively. Also, prednisolone at 0.5 mg/kg, twice a day inhibited the erosion by 53.3%. Thus, by measuring the dark blue area stained with 1% alcian blue solution, we could estimate macroscopically and objectively the area of erosions. This method seems to be a useful index for assessing the damages produced in the experimental ulcerative colitis model in rats.

Alcian Blue↗

PubMed1993

Primary intracranial germinoma involving the medulla oblongata--case report.

A 30-year-old female presented with intracranial germinoma involving both the medulla oblongata and suprasellar region. Such involvement of medulla oblongata with initial clinical symptoms similar to brainstem glioma has not been previously reported. Combination chemotherapy using cisplatin and etoposide achieved disappearance of the suprasellar tumor, and decreased size of the medulla oblongata tumor. Relapse occurred 6 months after first treatment, when combination chemotherapy with etoposide and carboplatin achieved reduction in tumor size again.

Adult↗

PubMed1993

Endoscopic examination of the upper gastrointestinal tract for the presence of second primary cancers in head and neck cancer patients.

Endoscopic examination of the upper gastro-intestinal tract with Lugol's solution staining was performed on 150 patients with head and neck cancer treated at the Departments of Otolaryngology and Radiology, Osaka University Hospital, between June 1987 and December 1991. Thirteen second primary cancers (11 esophageal and 2 gastric cancers) were found endoscopically, although prior fluoroscopy had found only 4 (3 esophageal and one gastric cancer). All of the 9 second primary cancers which were not detected by fluoroscopy were in the early stage. Both Brinkman's and Alcohol indices of double primary cancer cases were significantly higher than those of single head and neck cancer cases. These results indicate that head and neck cancer patients who smoke and/or drink heavily require thorough examination of their upper gastro-intestinal tract with endoscopy, using Lugol's solution staining, as well as with fluoroscopy.

Adenocarcinoma↗

PubMed1993

Reinforced cytotoxicity of lymphokine-activated killer cells toward glioma cells by transfection with the tumor necrosis factor-alpha gene.

Lymphokine-activated killer (LAK) cells generated from peripheral blood lymphocytes incubated with recombinant interleukin-2 were transfected with the human tumor necrosis factor (TNF)-alpha gene by means of novel liposomes with a positive change on their surface. The cells secreted significant amounts of TNF-alpha into the culture medium and exhibited reinforcement of cytotoxicity toward a human glioma cell line (U251-SP), being three times more cytotoxic than nontransfected LAK cells. The mechanism for the reinforcement of cytotoxicity is considered to involve not only an increase in TNF-alpha secretion from LAK cells but also its expression on their surface. Intratumoral or intrathecal injection of LAK cells transfected with the TNF-alpha gene may be useful for the treatment of patients with malignant gliomas.

Cytotoxicity, Immunologic↗

PubMed1993

[13C-urea breath test].

The 13C-urea breath test is now a practical and readily available alternative to endoscopy- and serology-based methods for the detection of H. pylori infection. It can detect very low levels of H. pylori colonization within the stomach by assessing the entire mucosa, and avoids the risks of sampling error. We performed the 13C-urea breath test in asymptomatic volunteers and patients with gastric and duodenal ulcers in order to compare the sensitivity and specificity by measurement of H. pylori antibody by ELISA. The positive rates of H. pylori in the 13C-urea breath test was correspondent with the results from the H. pylori antibody test, although no correlation in the antibody titers and urease activities was observed between the two methods. The 13C-urea breath test was the most useful method in evaluation of eradication of H. pylori after administration of antibiotics, compared to serological and pathological methods. These results suggest that the 13C-urea breath test is highly useful for the diagnosis of H. pylori infection of the gastric mucosa.

Adolescent↗

PubMed1992

Dipyridamole enhances an anti-proliferative effect of interferon in various types of human tumor cells.

The anti-proliferative activity of human interferon (HuIFN) was enhanced by dipyridamole, 2,6-bis-(diethanolamino)-4,8-dipiperidinopyrimido-[5,4-d]-py rimidine, when tested against various human tumor cell lines, including KT (breast carcinoma), PLC/PRF/5 (hepatoma), MGC-I, U251-SP and T98 (glioma), HAC-2 and SHIN-3 (ovarian carcinoma), and MM-ICB (melanoma). The enhancement occurred irrespective of the kind of HuIFN used (alpha, beta or gamma) and the original degree of susceptibility of the cells to HuIFN. Even low doses down to 0.01 microM of dipyridamole that had no intrinsic anti-proliferative activity could enhance the effect of HuIFN. The enhancement of HuIFN effects seems not to be caused by induction of HuIFN production, because neither anti-viral activity nor HuIFN antigens were detected in culture medium in cells treated with dipyridamole. Mopidamole, a derivative of dipyridamole lacking one piperidine residue, produced little enhancement of the effects of HuIFN. Among ovarian cancer cell lines tested, the enhancement of the activity of HuIFN by dipyridamole for HAC-2 and SHIN-3 cells was equivalent to or greater than that for 3 chemotherapy agents (adriamycin, vincristine, and a camptothecin derivative). However, neither HOC-21 ovarian cancer cells nor HEC-1 endometrial adenocarcinoma cells were susceptible to any combinations. When MGC-1, U251-SP, and HAC-2 cells were injected into nude mice, the growth of tumors was more markedly inhibited by the subcutaneous administration of HuIFN in combination with oral administration of dipyridamole than by the HuIFN alone. Thus, this combination therapy seems to be worth trying for human cancer, although the enhancement of the effects of HuIFN by dipyridamole varied among the cell lines examined.

Animals↗

PubMed1992

An experimental study on the treatment of hydrofluoric acid burns.

A 20% solution of hydrofluoric acid (HF) was applied to the skin of rats and a biomedical observation of the tissues and sera was made. Flushing with running water was effective for HF burns. By applying 2.5% calcium gluconate jelly, concentrations of fluoride in the urine and the tissues surrounding the injured region were reduced. Thus, the results proved that irrigation with running water and jelly applications were evaluated as the most effective therapy among various methods tested for HF burns.

Animals↗

PubMed1992

Serum fluoride as an indicator of occupational hydrofluoric acid exposure.

To define the relationship between ionic fluoride concentration in the serum of workers and the amount of hydrofluoric acid (HF) in the work environment, pre-and postshift serum and urine samples of 142 HF workers and 270 unexposed workers were examined. The maximum and minimum concentrations of HF in the air in each workshop varied from the mean by less than 30%. The preexposure levels of serum and urinary fluoride in HF workers were higher (P < 0.001) than the control values. This suggests that fluoride excretion from the body continues for at least 12h. The postshift serum and urinary fluoride concentrations of these workers were significantly higher (P < 0.001) than the preshift concentrations. A good correlation (r = 0.64) was obtained between postshift serum fluoride and postshift urine fluoride. There was a linear relationship between mean serum fluoride concentration and HF concentration in the workshop. A mean fluoride concentration of 82.3 micrograms/l with a lower fiducial limit (95%, P = 0.05) of 57.9 micrograms/l was estimated to correspond to an atmospheric HF concentration of 3 ppm. This is the maximum allowable environmental concentration recommended by the Japanese Association of Industrial Health, and it is also the threshold limit value suggested by the American Conference of Governmental Industrial Hygienists. The results demonstrate that exposure to HF can be monitored by determining the serum fluoride concentration.

Adolescent↗

PubMed1992

Quantitation of cytomegalovirus DNA in lung tissue of bone marrow transplant recipients.

Five bone marrow transplant recipients who died of respiratory failure were retrospectively analyzed with polymerase chain reaction (PCR) assay for pulmonary cytomegalovirus (CMV) infection. Two patients had CMV interstitial pneumonitis according to the virus isolation and the histologic and immunofluorescent examinations of the lungs, while the other three patients had non-CMV diseases (ie, idiopathic interstitial pneumonitis, pulmonary aspergillosis, or Streptococcus mitis septicemia). Cytomegalovirus DNA was amplified from the postmortem lung tissue with PCR. The PCR assay showed apparent PCR signals specific to CMV DNA in the two patients with CMV pneumonitis. In contrast, CMV DNA was hardly detectable or undetectable in the three patients without CMV disease. With quantitative PCR assay the initial CMV copy number in the lung tissue of the two patients with CMV pneumonitis was more than 10(4) copies/micrograms DNA and was over 1,000-fold more than that of the three patients without CMV pneumonitis. These results show that quantitative PCR assay could be useful as a diagnostic measure for pulmonary CMV infection.

Adolescent↗

PubMed1992

A novel core protein as well as polymorphic epithelial mucin carry peanut agglutinin binding sites in human gastric carcinoma cells: sequence analysis and examination of gene expression.

The peanut agglutinin (PNA)-binding site is protein-bound Gal beta 1-->3GalNAc, and is a tumor-associated carbohydrate marker expressed in many human carcinomas. PNA-binding glycoproteins isolated from KATO-III human gastric carcinoma cells were deglycosylated by trifluoromethanesulfonic acid, and rabbit antibodies against the core proteins were used to screen a lambda gt11 expression library constructed from these cells. Two different core proteins were identified by this approach. One was polymorphic epithelial mucin (PEM), initially found in breast carcinomas. PEM mRNA was expressed in normal tissues of the stomach, colon, and lung, but not in the small intestine, thyroid, and spleen. High levels of PEM mRNA were detected in some nude mouse-transplanted carcinomas, i.e. colorectal, pancreatic, stomach, and lung carcinomas. The other core protein was a novel one called MGC-24, which has a molecular mass of 24 kDa, is rich in hydroxyl amino acids and cysteine, and lacks repeating motifs. The mature MGC-24 glycoprotein behaved as a high-molecular-mass one upon SDS-polyacrylamide gel electrophoresis even after neuraminidase treatment. Treatment with endo-alpha-N-acetylgalactosaminidase in the absence of neuraminidase significantly changed the staining pattern by anti-MGC-24, confirming that MGC-24 carried PNA-binding sites. MGC-24 mRNA was intensely expressed in normal tissues of the colon, small intestine and thyroid, and in some nude mouse-transplanted colorectal and pancreatic adenocarcinomas.

Amino Acid Sequence↗

PubMed1992

Role of corpus luteum function in embryo implantation.

The present study was undertaken to evaluate the role of corpus luteum function in the implantation process of cryopreserved embryos. Six patients with tubal infertility were studied, with a total of 27 fresh embryos being replaced following controlled ovarian hyperstimulation and in vitro fertilization. These embryo transfers failed to produce pregnancy. From the patients, 22 supernumerary embryos were cryopreserved and 10 viable frozen-thawed embryos were transferred in a subsequent natural cycle, resulting in 2 pregnancies. In 1 of the pregnancies, the serum concentrations of estradiol (E2) and progesterone (P4) in the midluteal phase were 29 pg/ml and 5.6 ng/ml, respectively. These values were considered to be below the physiological range. These data suggest that a pregnancy can be achieved in spite of low circulating E2 and P4 levels during the luteal phase, which are generally indicative of the luteal phase defect.

Adult↗

PubMed1992

Tumor-specific binding of radiolabeled G-22 monoclonal antibody in glioma patients.

Iodine-131-labeled G-22 monoclonal antibody F(ab')2 fragment reaching specifically with a glioma-associated surface glycoprotein was administered to 12 glioma patients to investigate its use in radioimaging of intracranial gliomas. No immediate or delayed side effects were attributable to antibody injection. Nine patients received the radiolabeled complex intravenously. The images of low-grade gliomas were generally poor and disappeared within 4 days. High-contrast images were obtained beyond the 7th day in high-grade gliomas except one case in the pineal region. Three patients received intraventricular or intratumoral administration. Clear images of all tumors were demonstrated from the 2nd until later than the 7th day. One patient with cerebrospinal fluid (CSF) dissemination of brainstem glioma demonstrated negative CSF cytology after intraventricular administration.

Antibodies, Monoclonal↗

PubMed1992

Growth inhibition of glioma cells by liposome-mediated cell transfection with tumor necrosis factor-alpha gene--its enhancement by prior gamma-interferon treatment.

A new approach to the treatment of malignant glioma is cytokine gene therapy to produce growth inhibitors in cells. Previously, we showed that human glioma cells selectively transfected with the gene of interferon (IFN)-beta and/or IFN-gamma by our novel liposomes tagged with monoclonal antibody against a glioma-associated antigen achieved a remarkable growth inhibition effect. In the present experiment, we demonstrated the effectiveness of gene therapy against glioma cells using liposomes bearing a plasmid containing the gene for tumor necrosis factor (TNF)-alpha. We also found that the effect of endogenous TNF-alpha was enhanced by treatment of IFN-gamma prior to the transfection with the TNF-alpha gene.

Cell Division↗

PubMed1992

Effectiveness of interferon-beta, ACNU, and radiation therapy in pediatric patients with brainstem glioma.

Sixteen pediatric patients with brainstem glioma were treated with a combination of interferon-beta, 1-(4-amino-2-methyl-5-pyrimidinyl)-methyl-3-(2-chloroethyl)-3-nitroso ure a hydrochloride (ACNU), and radiation therapy (IAR therapy). All patients received 1-1.5 million IU/day of interferon-beta intravenously for 1 week of each 6-week cycle. In addition, ACNU (2-3 mg/kg) was given on the 2nd day of each cycle. Conventional focal irradiation (1.5-2 Gy/day for 5 days to a total dosage of 40-60 Gy) was administered beginning on day 3. Patients underwent at least two 6-week cycles. Adverse effects included nausea, vomiting, and myelosuppression, but were mild and transient. Response to treatment was evaluated by the reduction in tumor size measured on postcontrast computed tomographic scans and magnetic resonance images. Responses occurred in 10 of 11 patients with the intrinsic type of brainstem glioma, including three complete and seven partial responses. Two of five patients with exophytic type gliomas partially responded. The median survival was 15.7 months, a remarkable improvement over the natural course of this disease. These results indicate that IAR therapy is a useful primary treatment for pediatric patients with brainstem gliomas.

Adolescent↗

PubMed1992

Clinical effect of intra-arterial tumor necrosis factor-alpha for malignant glioma.

Recombinant human tumor necrosis factor-alpha was administered intra-arterially to treat 20 cases of malignant gliomas, mostly progressive or recurrent. The optimum dosage was determined to be 1 x 10(5) U/sq m/day. Among the 10 evaluable patients treated at this dosage, two responded (one completely and one partially), resulting in a 20% response rate. Side effects were mild and easily controllable. Improvement of neurological symptoms was noted in 47% of the patients a few days after treatment, even when computerized tomography showed no tumor regression. This might have been due to the pleiotypic biological activity of tumor necrosis factor-alpha. Neuroradiographic observations revealed narrowing of the tumor-feeding artery, a decrease in tumor staining ability, and necrosis in the central part of a tumor. The authors suggest that intra-arterial administration of tumor necrosis factor-alpha may be an effective treatment for malignant glioma, including recurrent cases.

Adolescent↗

PubMed1992

Cytotoxicity of human beta-interferon produced in human glioma cells transfected with its gene by means of liposomes.

The cytotoxicity of human beta-interferon (HuIFN-beta) produced in human glioma cells was examined by use of our liposomes entrapping two plasmids, pSV2neo and pSVMTV-IFN-beta. After the cells had been transfected with these genes by means of the liposomes, neomycin-resistant cells were selected. When the selected cells were subjected to a single exposure to dexamethasone, all of the cells were found to produce HuIFN-beta and were eliminated by 8 days. Accordingly, the effect of HuIFN-beta produced in human glioma cells is considered to be cytocidal.

Cell Death↗

PubMed1992

Surgical treatment of intrahepatic cholangiocarcinoma: four patients surviving more than five years.

BACKGROUND: To find the rational surgical strategy for the treatment of intrahepatic cholangiocarcinoma (ICC), clinical features of ICC were studied in 20 patients who underwent hepatic resection in the National Cancer Center Hospital from 1980 to 1990. METHODS: According to the morphologic pattern, we classified the ICCs into two subcategories, mass-forming and infiltrating, which correlated with their biologic behavior. RESULTS: Of 10 patients who underwent hepatectomy for mass-forming ICC, three survived more than 5 years without recurrence. The 1-, 3-, and 5-year survival rates were 59.3%, 44.4%, and 44.4%, respectively. Of 10 patients who underwent hepatectomy for infiltrating ICC, one survived more than 5 years without recurrence. The 1-, 3-, and 5-year survival rates were 72.0%, 27.0%, and 27.0%, respectively. The pathologic findings and recurrences indicated that the salient feature of the mass-forming type was its tendency for intrahepatic metastasis especially near a main lesion, and of the infiltrating type was the infiltrative spread via Glisson's capsule and hilar lymph nodal metastasis. CONCLUSIONS: An anatomic and extensive liver resection should be performed for mass-forming ICC, whereas a hepatectomy with excision of the extrahepatic bile duct and hilar lymph nodal dissection is recommended for infiltrating ICC.

Adenoma, Bile Duct↗