Screening of H-ras Gene Point Mutations in 50 Cases of Bladder Carcinoma

Background Mutation converts the H-ras gene into an activated oncogene in about 10% of human bladder cancers. Codons 12 and 61 are the major "hot spots" for activation. A simple and accurate method to detect point mutations in these codons may be clinically useful for early diagnosis of bladder cancer.
Methods Bladder cancer samples from 50 patients, plus 10 samples of normal bladder mucosa, were analyzed for possible point mutation of the H-ras gene at either codon 12 or codon 61. The H-ras gene DNA segments that include these 2 codons were amplified by PCR methods, then the possible presence of a point mutation was evaluated at each codon by susceptibility of the respective DNA segments to digestion with the restriction enzyme and by dot blot hybridization assay. A bladder cancer patient who had an H-ras gene mutation was examined to see whether the mutation was also detectable in the cells released in the urine.
Results Definite or possible point mutations were found in 6 (1 2%) out of 50 bladder cancer patients, while no mutation was detected in normal mucosa. A point mutation could also be detected in cells isolated from the patient's urine sample.
Conclusion The prevalence of point mutations at codon 1 2 or codon 61 of the H-ras gene found in this study was similar to that previously estimated for human bladder cancer by DNA transfection assay. The method we have used for detecting point mutations of the H-ras gene provides a simple and highly accurate way to detect mutated cancer cells even in the urine. It may be clinically usable for early diagnosis of bladder cancer.     

Beta 2-microglobulin synthesis of mononuclear cells in chronic dialysis patients.

Beta 2 microglobulin (B2M) has been identified as a major component of amyloid deposits. This study was designed to determine whether changes occur in the synthesis of B2M in dialysis patients. Mononuclear cells (MNC) were isolated in peripheral blood from healthy volunteers, patients on hemodialysis (HD) and on continuous ambulatory peritoneal dialysis (CAPD). MNC were cultured in a medium of RPMI 1640 with or without interleukins IL-1, IL-2 or interferon INF-r. B2M in the cultured cells and supernatant was measured by enzyme immunoassay. IL-2 or INF-r stimulated B2M synthesis was significantly lower (25%) in patients on HD than in normal controls regardless of the type of dialysis membranes used, with no change in basal B2M synthesis. No differences were detected between healthy volunteers and CAPD patients. Preincubation of MNC with complement--activating or non-complement--activating membrane had no influence on B2M synthesis. The basal B2M synthesis of MNC significantly increased after a 4-hour HD regardless of the membranes used, and IL-2 and IFN-r stimulated synthesis were both essentially the same before and after HD. It was thus concluded that maximum capacity for B2M synthesis of MNC decreases in hemodialysis patients. This low responsiveness of MNC may be partially the cause for the reduction in cell-mediated immune response in HD patients.     

Effect of long term treatment with oxitropium bromide on airway secretion in chronic bronchitis and diffuse panbronchiolitis.

BACKGROUND--Anticholinergic bronchodilator drugs improve lung function in chronic bronchitis but less is known of their effects on the volume and physical properties of sputum in conditions associated with excessive airway secretions. This study examines the effects of the regular use of oxitropium bromide in such patients. METHODS--The study was conducted in a parallel, double blind, placebo controlled fashion. Patients were divided into two groups: the first group (n = 17) received oxitropium bromide from a metered dose inhaler (two puffs three times daily; 100 micrograms/puff) for eight weeks, and the second group (n = 16) received placebo. Lung function was measured as forced expiratory volume in one second (FEV1) and vital capacity. In evaluating airway secretion, daily amount of expectorated sputum, percentage solid composition, viscoelastic properties including elastic modulus and dynamic viscosity, and sputum microbiology were determined. RESULTS--Oxitropium bromide increased FEV1 and decreased the mean (SE) sputum production from 61(4) to 42(3) g/day after treatment, whereas placebo had no effect. Bacterial density and sputum flora were unchanged, but solid composition and elastic modulus increased from 2.52(0.43)% to 3.12(0.34)%, and 68(12) dyne/cm2, respectively, in the group taking oxitropium bromide. CONCLUSIONS--Regular treatment with oxitropium bromide not only improves airflow limitation but also reduces sputum production, probably through the inhibition of both mucus secretion and water transport, the latter component being predominant.     

Possible involvement of organic anion transporter 2 on the interaction of theophylline with erythromycin in the human liver.

Organic anion transporter 2 (Oat2 [SLC22A7]) is a multispecific organic anion transporter. Although several substrates of human Oat2 (hOat2) have been elucidated, a possible involvement of hOat2 in drug interaction is less defined. The purpose of this study was to investigate the interaction of theophylline with erythromycin mediated by hOat2 using a Xenopus laevis oocyte expression system. When expressed in Xenopus oocytes, hOat2 mediated the transport of theophylline and erythromycin. The finding indicates that the two compounds are novel substrates for hOat2. The apparent K(m) values for the uptake of hOat2 that mediated the transport of theophylline and erythromycin were 12.6 muM and 18.5 muM, respectively. The hOat2-mediated uptake of [(14)C]theophylline and [(14)C]erythromycin was cis-inhibited by adding erythromycin and theophylline, respectively. Our present findings suggest that hOat2 may, at least in part, be involved in the theophylline-erythromycin interaction in the human liver.     

Anaplastic ganglioglioma with sarcomatous component: An immunohistochemical study and molecular analysis of p53 tumor suppressor gene

The present case report describes a case of ganglioglioma with a distinct sarcomatous component in the left temporal lobe of a 59‐year‐old Japanese man. Neoplastic neuroglial tissue contained both benign and anaplastic glial components with a MIB‐1 labeling index of 0.1% and 12.0%, respectively. Sarcomatous tissue adjacent to the anaplastic glial tissue was dominated by pleomorphic fibroblastic cells with a MIB‐1 labeling index of 10.8%. They were immunoreactive for smooth muscle actin, type IV collagen, and alpha 1 antitrypsin, but not for desmin and CD34. Interestingly, some of the sarcomatous cells were double‐positive for smooth muscle actin and GFAP. The p53 protein had accumulated in the anaplastic astrocytes and sarcomatous cells, but direct DNA sequencing of PCR products failed to detect any mutation in the p53 gene (from exon 4 to exon 10).     

Studies on the metabolic fate of 14C-rokitamycin. III. Transmigration to fetus or milk

Transmigration of 14C-radioactivity to fetus or milk were studied in 17-18 day-pregnant rats and mother rats on the 14th day after parturition after a single oral administration of 14C-rokitamycin (TMS-19-Q) at a dose of 200 mg/kg. The blood concentration of the drug in the mother reached a maximum level of 22.8 micrograms/ml at 2 hours after administration. Maximum concentrations of TMS-19-Q in placenta, ovary and uterus were attained in 2 hours, and were 28.9, 26.0 and 26.2 micrograms/g, respectively. The distribution to these tissues were considered good. The maximum concentration of TMS-19-Q in the amniotic fluid was attained in 2 hours, at a level of 5.4 micrograms/ml. The transmigration to the amniotic fluid was considered poor. The maximum concentration of the drug in the fetus was achieved in 2 hours at a level of 13.7 micrograms/g. Maximum concentrations of the drug in fetal liver and brain were attained in 4 hours, and were 32.8 and 11.4 micrograms/g, respectively. Whole body autoradiography was done when the radioactivity in maternal blood reached peak concentration. It was found that radioactivities in placenta and fetal membrane were similar to the radioactivity in maternal blood, while the radioactivity in fetal brain was considerably lower than that in maternal blood. Maximum concentrations were found at 1 hour in the blood and at 4 hours in the milk, and were 14.8 and 21.5 micrograms/ml, respectively. Transmigration to the milk was good.