Biomedical subjects

J Yoshida

Publications and source records attributed to J Yoshida.

At least 235 records · Page 13Linked to original sources

PubMed1996

Cytolysis of malignant glioma cells by lymphokine-activated killer cells combined with anti-CD3/antiglioma bifunctional antibody and tumor necrosis factor-alpha.

With the aim of developing an effective immunotherapy for malignant glioma, glioma cells were incubated with tumor necrosis factor-alpha (TNF-alpha) to increase their susceptibility to lysis by lymphokine-activated killer (LAK) cells. Treatment with exogenous TNF-alpha induced the expression of intercellular adhesion molecule-1 (ICAM-1) on the surface of glioma cells. In addition, the cytolytic activity of LAK cells toward exogenous TNF-alpha treated glioma cells was significantly greater than LAK cell activity toward untreated glioma cells. This increase in cytolytic activity was blocked by anti-ICAM-1 monoclonal antibodies (MAb). Furthermore, co-treatment with a bifunctional antibody (BFA) composed of anti-CD3 (UCHT1) and antiglioma (G-22) antibodies synergistically increased the cytolytic activity of LAK cells towards TNF-alpha-treated glioma cells. These results indicate that a combination of exogenous TNF-alpha and anti-CD3/antiglioma BFA may provide an effective modified adoptive immunotherapy for patients with malignant glioma.

Antibodies, Bispecific↗

PubMed1996

Inferior vena caval thrombus associated with double neoplasms of the retroperitoneum and kidney: report of a case.

We report herein the case of a patient we recently encountered who was found to have a giant retroperitoneal tumor coincident with tumor thrombus in the inferior vena cava (IVC). On the assumption that the origin was retroperitoneal, the two lesions were resected using an intracaval filter. However, histopathological examination of the specimens revealed neurilemoma for the retroperitoneal tumor and adenocarcinoma for the tumor thrombus. A right renal tumor was subsequently detected, which led to right nephrectomy being performed en bloc with part of the IVC using a venoarterial bypass. Microscopy revealed carcinoma of the Bellini duct, or collecting duct, which is an extremely rare tumor. Retrospectively, a lesion with soft tissue density was noted in the renal vein. Surgical management focused on the prevention of pulmonary embolism. We describe this case because of its extreme rarity and its significance from the viewpoint of diagnosis and therapeutic strategies.

Aged↗

PubMed1996

Single oral dose of cisapride accelerates gastric antral emptying in healthy humans: an ultrasonographic study.

An ultrasonographic study of ten healthy volunteers was carried out to evaluate the effect of cisapride on gastric antral emptying. More than 1 week after the measurement of the baseline emptying rate, cisapride was given at a single oral dose of 5 mg 30 minutes before intake of a balanced liquid test meal (5 ml/kg body weight). To determine the time to half emptying (T1/2), an exponential curve was extrapolated for the elimination phase of the gastroantral sagittal cross-sectional area plotted against time. The T1/2 was reduced by 18.5% after cisapride, from 62.6 +/- 4.3 to 51.0 +/- 4.4 min (P = 0.0284). We conclude that a single oral dose of 5 mg of cisapride significantly accelerates the gastric antral emptying rate in healthy humans.

Administration, Oral↗

PubMed1996

Blood gas analysis of placental and uterine blood during cesarean delivery.

OBJECTIVE: To measure blood gases in uterine venous blood and maternal and fetal blood from the placenta, and to characterize gas exchange in the intervillous space. METHODS: Blood gas measurements were performed immediately after collecting placental and uterine blood from the subchorial and marginal lakes, from the chorionic vein and artery in the placenta in utero, and from the uterine vein during 12 cesarean deliveries. RESULTS: The mean oxygen pressure (PO2) values of the chorionic vein and subchorial lake were 28.7 +/- 6.0 and 29.9 +/- 7.5 mmHg, respectively, with a difference of 1.2 mmHg. The individual data for PO2 of the chorionic vein exceeded those of the subchorial lake in five subjects and were almost equal in two of the 12 subjects. The mean values of carbon dioxide pressure (PCO2) and bicarbonate were greater in the chorionic vein than in the subchorial lake, but the mean pH values were the same in the two groups. The mean values of blood gas analysis were not different between subchorial and marginal lakes with similar blood composition. The mean PO2 of the uterine vein in ten subjects was 45.9 mmHg, significantly higher than that of the subchorial lake. CONCLUSIONS: The human placenta may be defined as a multivillous model with a high degree of oxygen transfer. Arteriovenous anastomoses are suspected in the pregnant uterus beyond 37 weeks' gestation. Subchorial and marginal lakes contain similar admixed blood, which circulates and performs gas exchange.

Blood Gas Analysis↗

PubMed1996

Effect of testosterone on carbonic anhydrase and MG(2+)-dependent HCO3-stimulated ATPase activities in rat kidney: comparison with estradiol effect.

Effects of testosterone administration (TP; 1-3 mg/kg body weight, S.C., once daily for 7 days) on the cytosol carbonic anhydrase (CA) and tubular brush border Mg(2+)-dependent HCO3(-)-stimulated ATPase (Mg(2+)-HCO3(-)-ATPase) activities of normal and castrated male and female rat kidney were compared with estradiol (E2) effects. TP decreased kidney CA activity in a dose-dependent manner in all four animal conditions, and negative correlations were observed between cytosol CA activity and serum testosterone concentration. However, brush border Mg(2+)-HCO3(-)-ATPase activity was not affected by testosterone. Orchiectomy increased only CA activity and its value recovered to normal levels by 3 mg/kg TP replacement, whereas Mg(2+)-HCO3(-)-ATPase activity did not change. In the previous study, on the other hand, E2 administration activated both kidney enzymes in normal male rats and only Mg(2+)-HCO3(-)-ATPase in normal female rats. Testosterone and E2 conversely affected kidney CA activity in male rats. These facts suggest that the cytosol CA may control kidney functions on H+ and HCO3- metabolism under the balance of both sex hormones in the living body.

Adenosine Triphosphatases↗

PubMed1996

Outbreak of multi-drug resistant Staphylococcus aureus: a cluster analysis.

BACKGROUND: Outbreaks of multi-drug resistant Staphylococcus aureus over eight years were investigated to prevent future endemic. METHODS: Isolates of multiresistant S. aureus underwent a cluster analysis combined with canonical discriminant analysis using bacteriologic biotyping and sensitivity to 21 drugs. RESULTS: Of a total of 786 strains recovered from 155 in-patients, the specialty surgical ward (SW) exhibited 470 isolates (59.8%) and the general SW 214 (27.2%). Among six clusters formed, four clusters were predominant in the general SW. An ordination diagram from the canonical discriminant analysis revealed a distribution in which clusters were localized temporally (year) and spatially (ward). A yearly shift of clusters indicated emergence of a new phenotype of multiresistant S. aureus. CONCLUSIONS: The cluster analysis of isolates of multiresistant S. aureus using biotyping and sensitivity may supplement the classical method of tracing the spreading patterns of this microbe.

Anti-Bacterial Agents↗

PubMed1996

New approach for the treatment of medulloblastoma by transfection with glial fibrillary acidic protein gene.

Glial fibrillary acidic protein (GFAP) is one of the intermediate filaments found in mature normal astrocytes and differentiated glioma cells. It seems to be able to stabilize the cytoskeleton of the astrocyte and may play a role in maintaining astrocyte cell shape, in association with other cytoskeletal components such as microfilaments and microtubles. However, its tissue-specificity remains unclear. To clarify the effect of GFAP expression in brain tumour cells, transfer of the GFAP gene into the human medulloblastoma cell line, DAOY-1 (which does not express GFAP) was carried out using liposomes. Upon transfection, we observed the alterations in the characteristics of GFAP transfected cells. Cell growth, morphology and sensitivity to anticancer drugs were compared between GFAP gene transfected DAOY-1 and control DAOY-1 cells. Growth inhibition and increase of sensitivity to anticancer drugs were observed with GFAP expression in GFAP gene-transfected DAOY-1 cells. However, no morphological changes were noted.

Brain Neoplasms↗

PubMed1996

Streptococcal glycoprotein-induced tumour cell growth inhibition involves the modulation of a pertussis toxin-sensitive G protein.

We studied the mechanism of anti-tumour action of sulphydryl glycoprotein (SAGP) purified from an extract of Streptococcus pyogenes in vitro. SAGP rapidly inhibited the incorporation of nucleic acid precursors into murine fibrosarcoma (Meth A) cells before it inhibited the cell growth. SAGP-induced cell growth inhibition was diminished by incubating the cells with pertussis toxin (IAP), whereas the SAGP activity was augmented by incubating the cells with cholera toxin (CTX). Meth A cells exposed to SAGP underwent an increase in labelling of the alpha-subunit of an inhibitory guanine nucleotide-binding (Gi) protein in a subsequent IAP-catalysed [32P]ADP ribosylation of the cell membrane fraction. Gi alpha labelling was not increased either in the membrane from the Meth A cells exposed to heat-inactivated SAGP or in the membrane from L929 cells exposed to SAGP, in which growth was also unaffected. By contrast, SAGP caused no alteration in labelling the alpha-subunit of stimulatory guanine nucleotide-binding (Gs) protein in a subsequent CTX-catalysed ADP ribosylation of membrane fractions of Meth A and L929 cells. The amount of intracellular cAMP was decreased slightly in Meth A cells incubated with SAGP. Although the precise roles of Gs protein and adenylate cyclase in the cell growth inhibition induced by SAGP are not clear, these findings suggested that the modulation of Gi protein is involved in such SAGP-induced cellular events as the inhibition of nucleic acid synthesis and cell growth inhibition.

Adenosine Diphosphate Ribose↗

PubMed1996

Monoclonal antibody against the fusion junction of a deletion-mutant epidermal growth factor receptor.

A mouse monoclonal antibody (IgG2b), 3C10, was produced against the truncated epidermal growth factor receptor (EGFR), encoded by the (type III) in-frame deletion mutation of 801 nucleotides of EGFR affecting the external domain, known to be expressed in some human glioblastoma. As this mutation newly generates a glycine residue at the fusion point, a 14 amino acid peptide around the fusion junction including this glycine was chemically synthesised and used for immunisation of (B6 x DBA/2) F1 mice. Flow cytometric analysis showed 3C10 antibody staining of a mouse NIH/3T3 transfectant (ERM5) with the type III EGFR deletion-mutant gene, but not one with wild-type EGFR. The antibody immunoprecipitated the truncated EGFR protein with a molecular mass of approximately 140 kDa from ERM5 cells. Immunostaining of glioblastomas revealed binding in the case with the type III EGFR mutation, the five other specimens without the mutation being negative despite overexpression of EGFR in some cases.

3T3 Cells↗

PubMed1996

Endobronchial lipoma: a report of three cases.

Although lipomas are common benign neoplasms of soft tissue, endobronchial lipoma is rare. We have treated three patients with endobronchial lipoma over the five years. In two of them lesions were located in segmental or subsegmental bronchi and produced no symptoms. There are very few such cases reported in the English medical literature. In the first case, pneumonectomy was performed because of destruction of the lung due to recurrent pneumonia. The second case had no symptoms and the tumor was located at the bifurcation of right B4a and B4b. A right middle lobectomy was performed, because the distal end of the tumor could not be visualized by fiberoptic bronchoscopy. In the third case, which was a case of lung cancer, an endobronchial lipoma was found during fiberoptic bronchoscopy, and was completely removed endoscopically. Due to their benign nature, endobronchial lipomas should be initially treated with endoscopic surgery or endoscopic laser vaporization. Nevertheless, if the tumor is large and dumbbell-shaped on tomography or CT, endoscopic procedures are not appropriate. Furthermore, if destructive pulmonary change due to the tumor is severe, the remaining peripheral lung will not recover after endoscopic procedures, even if they are removed successfully. When the biopsy specimen is too small to allow evaluation of the whole tumor, surgical resection should also be considered for definitive diagnosis.

Aged↗

PubMed1996

A case of extragonadal germ cell tumor with elevated postchemotherapy HCG successfully treated by resection of a solitary metastasis and chronic oral etoposide.

We report a 39 year-old man with disseminated extragonadal germ cell tumor (GCT), whose serum level of human chorionic gonadotropin (HCG) increased again after platinum-based combination chemotherapy, high-dose chemotherapy with autologous bone marrow rescue and radical adjunctive surgery. The increase in the HCG level was progressive in spite of multiple chemotherapy, and after a while, a coin lesion in the right lung was identified by chest roentgenography. The pulmonary lesion was refractory to additional chemotherapy. After a systemic survey to confirm that the lesion was solitary, video-assisted thoracoscopic wedge resection of the right lower lobe was performed. Because the resected tumor included viable tumor cells and the serum HCG level remained slightly high one month after the operation, oral low-dose etoposide was begun. In a short time, the level of the serum tumor marker decreased and remained normal during the subsequent 7 months of therapy and thereafter. The patient remains in complete remission 13 months after completion of the final therapy and 3 years after the initial diagnosis. Even if the level of a serum tumor marker is high, salvage resection can be a promising therapeutic option for operable tumors that are refractory to chemotherapy. The usefulness of chronic oral etoposide for patients with GCT should be examined by further clinical trials.

Administration, Oral↗

PubMed1996

Tumor necrosis factor-alpha gene transfer augments anti-Fas antibody-mediated apoptosis in human glioma cells.

To effectively induce apoptosis in human glioma cells, we tried to transfer the tumor necrosis factor (TNF)-alpha gene into glioma cells to produce TNF-alpha locally in these cells. The stable transfectants of three glioma cells (U251-SP, U251-MG, and T98G) were resistant to exogenous TNF-alpha, but their cell surface expression of the Fas antigen was dramatically enhanced by about 10 to 100-fold as compared with untransfected glioma cells exposed to exogenous TNF-alpha. The Fas antigen is a transmembrane cytokine receptor protein of the nerve growth factor/TNF receptor superfamily. Although the untransfected glioma cells tested were resistant to anti-Fas antibody-mediated apoptosis, the TNF-alpha gene-transfected glioma cells exhibited high susceptibility to anti-Fas antibody-mediated apoptosis. Thus, TNF-alpha gene transfer combined with anti-Fas antibodies may be useful for the treatment of malignant glioma.

Antibodies↗

PubMed1996

Intracellular hyperthermia for cancer using magnetite cationic liposomes: in vitro study.

'Magnetite cationic liposomes (MCL)' were developed as a means to generate intracellular hyperthermia. Affinity of the MCL to glioma cells was ten times higher than that of magnetite 'neutral' liposomes due to the electrostatic interaction based on the positive charge of the MCL. Heat generation of the MCL was studied using agar phantoms and small pellets of rat glioma cells. When a high-frequency magnetic field, 118 kHz, 384 Oe was applied to glioma cells in the presence of MCL, the glioma cell pellet of 80 microl (5.4 mm in diameter) was heated to over 43 degrees C and all the cells died after 40 min irradiation owing to the hyperthermic effect. The terminal temperature of the cell pellet was proportional to the pellet volume when other parameters were constant. It thus appears that the MCL can heat a tumor of more than 80 microl in volume to above 42 degrees C.

Adsorption↗

PubMed1996

Atrophic changes of gastric mucosa are caused by Helicobacter pylori infection rather than aging: studies in asymptomatic Japanese adults.

BACKGROUND: The current study was designed to evaluate the effect of aging and Helicobacter pylori infection on the gastric mucosa in asymptomatic Japanese adults. MATERIALS AND METHODS: Eighty-five asymptomatic healthy adults were recruited from a health-screening center in Sapporo. All subjects underwent endoscopy and gastric biopsy, and serum was obtained for IgG antibodies to H. pylori, serum gastrin, and pepsinogen levels. RESULTS: The prevalence of atrophic change of the gastric mucosa assessed by pathological findings increased with age (49% in the 30- to 39-year-old group compared to 89% in those 60 years and older, p < .001). The frequency of intestinal metaplasia also increased with age (38% in the 30- to 39-year-old group compared to 82% in those 60 years and older, p < .001). In contrast, the frequency of atrophic gastritis and intestinal metaplasia was extremely low in the H. pylori seronegative group regardless of age. Mean serum gastrin level in H. pylori-positive adults was significantly greater than in those who were H. pylori-negative (114.3 +/- 11.2 compared to 65.8 +/- 6.5 pg/ml, p < .03). The serum pepsinogen I-II ratio was significantly lower in those with H. pylori infection than in those without (3.1 compared to 6.6, p < .0001). CONCLUSIONS: These results suggest that the chronological changes in the gastric mucosa in Japanese individuals are either entirely related to H. pylori infection or the process is greatly accelerated by H. pylori infection.

Adult↗

PubMed1996

Repeated exposure to cationic immunoliposomes activates effective gene transfer to human glioma cells.

The use of whole immunoglobulin G (IgG) and F(ab')2 of the G-22 monoclonal antibody associated with cationic liposomes (immunoliposomes) and the effect of repeated exposure were investigated for the transfection of the LacZ gene to various glioma cell lines. Immunoliposomes associated with either whole IgG or F(ab')2 monoclonal antibody caused an about 2-fold increase in beta-galactosidase activity compared with liposomes associated with no antibody in glioma cell lines expressing the CD44 antigen. beta-Galactosidase activity was further increased by about 2-fold by repeated exposure compared with single exposure. A glioma cell line not expressing the CD44 antigen showed no such increase in beta-galactosidase activity. These results indicate that repeated exposure of cationic immunoliposomes achieves a higher transfection efficiency and is a potentially effective method of gene therapy for patients with malignant glioma.

Antibodies, Monoclonal↗

PubMed1996

Major salivary gland lesions: correlation of MR findings with flow cytometric DNA analysis and prognosis.

OBJECTIVE: We correlated MR imaging findings with those from flow cytometry and determined prognostic factors of patients with major salivary gland lesions. SUBJECTS AND METHODS: DNA ploidy (11 aneuploid, 35 diploid lesions) and S-phase fraction (SPF) (12 high-SPF, 28 low-SPF lesions) percentages as determined by flow cytometric technique in 46 major salivary gland lesions were correlated with MR findings and signal-intensity ratios of lesion to muscle on fast spin-echo T2-weighted images, unenhanced spin-echo T1-weighted images, and gadolinium-enhanced fat-suppressed spin-echo T1-weighted images. SPF percentages were correlated with the three signal-intensity ratios by stepwise regression analysis. Prognostic indicators of disease-free survival were assessed with Cox multivariate analysis (range of follow-up, 2-50 months; mean, 16.6 months). RESULTS: Signal-intensity ratios for all pulse sequences were significantly smaller in aneuploid lesions than in diploid lesions. Incidence of ill-defined margins (p < .001), invasion (p = .014), and hypointensity to the gland on T2-weighted images (p = .047) was significantly higher in aneuploid lesions than in diploid lesions. Of these, signal-intensity ratios on enhanced T1-weighted images were most accurate for predicting aneuploidy. A threshold of 1.55 for signal-intensity ratios on enhanced T1-weighted images yielded the highest accuracy (86%) for aneuploidy. Signal-intensity ratios on T2-weighted images (p = .025) and enhanced T1-weighted images (p < .001) were significantly smaller in high-SPF lesions than in low-SPF lesions. A threshold of 1.73 for signal-intensity ratios on enhanced T1-weighted images yielded 73% accuracy for high-SPF lesions, which was inferior to the prediction possible from ill-defined margins (80% accuracy). Aneuploidy (p = .008), ill-defined margins (p = .036), and signal-intensity ratios on unenhanced T1-weighted images (p = .008), related significantly and negatively to disease-free survival. A signal-intensity ratio of 1.22 or less for unenhanced T1-weighted images indicated a high risk of developing recurrence (100% sensitivity). CONCLUSION: MR findings and signal-intensity ratios can reflect DNA ploidy and SPF status and can predict prognoses for patients with major salivary gland lesions.

Adolescent↗

PubMed1996

Practical classification of the branching types of the biliary tree: an analysis of 1,094 consecutive direct cholangiograms.

BACKGROUND: The structure of the biliary tree has been classified according to the relationship between the hepatic segmental ducts and the cystic duct. Because laparoscopic cholecystectomy demands precise knowledge of biliary anatomy, we propose a simplified classification of the bile ducts. STUDY DESIGN: A consecutive series of 1,094 direct cholangiograms were analyzed and the letters A, P, R, L, and C were designated for the right anterior, right posterior, right, left, and cystic ducts, respectively. The arborizing patterns of the hepatic bile ducts were classified into either the bifurcation of the right and left ducts (RL); triple confluence of the right anterior, right posterior, and left ducts (APL); separate branching of A and P in the duodenohepatic direction; or discrete branching of P and A (P-AL) where branches A and P were in reverse of A-PL. Cystic duct anomaly was added in parentheses. RESULTS: The classified ducts had the following distribution: RL, 67.7 percent; APL, 17.7 percent; A-PL, 8.0 percent; and P-AL, 6.0 percent. Cystic duct anomalies occurred in 1.6 percent of all the cases and were in frequent association with the P-AL pattern. The most common type was P-AL (P-C) seen in 0.5 percent of cases, where the cystic duct merged into the lower branching P. CONCLUSIONS: Our practical classification of the biliary tree anatomy may contribute to the practice of biliary surgery.

Adult↗

PubMed1996

ASA physical status and age are not factors predicting morbidity, mortality, and survival after pancreatoduodenectomy.

To evaluate the effects of age and physical status on postoperative complications, American Society of Anesthesiologists-Physical Status score (ASA score) and age were analyzed in patients undergoing pancreatoduodenectomy (PD). Medical records and follow-up results of 69 patients who had undergone PD from 1980 to 1993 at one institution were examined. Clinical variables affecting morbidity and mortality rates were analyzed, and compared between two-aged groups (> or = 70 years (n = 18) and < 70 (n = 51)). Univariate Cox regression analysis of 69 patients showed that ASA score and age were not significant factors affecting postoperative morbidity, mortality, and survival. The clinical variables including ASA score, gender, operative time, blood loss, stage, and location of carcinoma were similarly distributed between the two-aged groups. The mortality rate in patients less than 70 years of age was 5.9 per cent (3/51), whereas there was no mortality in patients more than 70 years of age. The morbidity, mortality, and cumulative survival rates were statistically similar in the two age groups. The results suggest that ASA-physical status and age are not limiting factors for PD and do not predict survival. The procedure is safe and worthwhile even in patients more than 70 years of age with the ASA score up to III.

Age Factors↗