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Biomedical subjects

H Ohmori

Publications and source records attributed to H Ohmori.

At least 343 records · Page 19Linked to original sources

A novel type of E. coli mutants with increased chromosomal copy number.

We have isolated E. coli mutants which can grow at 30 degrees C but not at 42 degrees C and are able to harbor the oriC plasmid (minichromosome) at a higher copy number than the parental wild-type strain at the permissive temperature. The mutants were found to contain higher amounts of chromosomal DNA per mg protein than the wild-type, whether or not they harbor the plasmid. Experimental results suggest that the higher amount of chromosomal DNA is due to a higher copy number of chromosomes and not to a larger amount of DNA per chromosome. These properties in each of the mutants are caused by a single mutation at the rpoB or rpoC gene that code for the beta or beta' subunit of RNA polymerase, respectively. The mutations are thought to affect the regulation of replication of oriC-bearing replicons, that is, the E. coli chromosome and oriC plasmids, but not the miniF plasmid.

Bacterial Proteins↗

Toyopearl HW-65C: ammonium sulfate as a new column chromatographic adsorbent for enzyme purification.

We found that Toyopearl HW-65C gel matrix adsorbed ferredoxin and ferredoxin-NADP+ reductase in the presence of concentrated ammonium sulfate. Ferredoxin was strongly adsorbed on the gel in 80% saturated ammonium sulfate, and ferredoxin-NADP+ reductase was adsorbed in 40% saturated ammonium sulfate. The phenomenon was utilized for purification of ferredoxin and the reductase on a Toyopearl HW-65C: ammonium sulfate column. The technique greatly simplified the early stage of purification of ferredoxin and the reductase. The improved purification methods further involved column treatments with DEAE-Toyopearl 650M and Matrex Red A. The effectiveness of the columns is reported. Since a number of other proteins such as cytochrome c, myoglobin, chymotrypsinogen A, ovalbumin, and glucose oxidase were also adsorbed well in an appropriately concentrated ammonium sulfate solution, the method may be of general use in enzyme purification.

Adsorption↗

Studies of single calcium channel currents in rat clonal pituitary cells.

Single Ca channel currents in tissue cultured clonal cells (GH3) isolated from a rat anterior pituitary tumour were studied with a patch voltage-clamp electrode filled with 100 mM-BaCl2 solution. The open time histogram was reasonably well expressed by a single exponential function with a time constant, which was about 1 msec and almost voltage-independent in the range of membrane potential studied (-20 to +40 mV). The closed time histogram was expressed by a sum of two exponential functions, one with a relatively voltage-independent time constant of about 1 msec and the other with a substantially larger voltage-dependent time constant. The latency (the time from the onset of the voltage-clamp pulse to the first channel opening) histogram could be expressed as the difference of two exponential functions with time constants which appeared to be voltage-dependent. The tentative conclusion is that the channel enters the activated state with voltage-dependent and relatively slow kinetics, and then flickers between open and closed states with substantially faster and relatively voltage-independent kinetics. The amplitude of the single channel current was similar to that estimated from noise analysis of the whole cell current (about -0.7 pA at 0 mV in 100 mM-BaCl2 solution); the apparent slope conductance was about 7-8 pS.

Animals↗

Effect of N-(2-carboxyphenyl)-4-chloroanthranilic acid disodium salt (CCA) on the induction of helper and suppressor T cells in vitro and in vivo.

Keyhole lympet hemocyanin (KLH)-specific suppressor T (Ts) cells that suppress the in vitro secondary anti-trinitrophenyl (TNP) PFC response to TNP-KLH could be induced when murine spleen cells were precultured with KLH. N-(2-carboxyphenyl)-4-chloroanthranilic acid disodium salt (CCA) at 1-100 micrograms/ml augmented the in vitro induction of Ts cells when the cells were precultured with a suboptimal dose of KLH (10 micrograms/ml). Ts cell-induction was, however, rather slightly inhibited by the same concentrations of CCA when the lymphocytes were precultured with an optimal amount of KLH (100 micrograms/ml). In the in vivo experiments, the daily administration of 10 mg/kg CCA for 4 weeks augmented or inhibited Ts cell-induction when mice were immunized with a suboptimal (30 micrograms/body) or an optimal (100 micrograms/body) amount of KLH, respectively. However, CCA had no effect on the induction of Ts cells by concanavalin A in vivo. On the other hand, CCA augmented the induction of helper T (Th) cells both in vitro and in vivo when Th cells were induced with a suboptimal amount of antigens. In contrast, the augmentative effect was no longer observed when Th cells were induced by an optimal amount of antigens. These results suggest that CCA is a compound showing immunomodulating properties that affect Ts and Th cell-induction depending on immunological conditions. These immunopharmacological profiles are discussed in connection with its clinical application to an autoimmune disease like rheumatoid arthritis.

Animals↗

Prostatic malacoplakia: a case report with a review of 49 cases of malacoplakia of various sites in Japan.

We reported a 62-year-old man with malacoplakia of the prostate, and reviewed 49 cases of malacoplakia hitherto observed in Japan in which the lesions originated from the urogenital tract, except for one gastric case. E. Coli was emphasized as a possible causative agent for malacoplakia especially in the urogenital tract. The possible histiocytic origin of von Hansemann cells was stressed by demonstrating cytoplasmic processes and desmosomes in our prostatic case. An adjuvant use of cholinergic agents and ascorbic acid with chemotherapeutic agents was recommended for treating malacoplakia.

Histiocytes↗

Human urinary cytology using a "direct mapping" technique: a combined light and scanning electron microscopic investigation.

A total of 252 bladder-washing and voided specimens from normal, and inflammatory and malignant lesions were examined by a direct mapping technique, i.e., a combined use of light (LM) and scanning electron microscopy (SEM). A newly-designed mesh, which consists of a piece of gelatine-covered, osmium-impregnated and polylysine-coated glass-slip with 42 compartments/25 mm2, was used in this study. This mesh permitted us to directly correlate LM and SEM images, which resulted in a shortening of the observation time. Malignancy of exfoliated urothelial cells has been determined on the basis of the presence or absence of pleomorphic microvilli as observed by SEM. Subsequently, a new "SEM grading" system for human urinary cytology was proposed. The direct mapping technique has enhanced the accuracy of the diagnosis over conventional methods, especially in cases of noninvasive, low-grade malignant tumors of the urinary bladder.

Blood Group Antigens↗

T4-labeling technique and its applications with particular reference to blood group antigens in bladder tumors.

A variety of visual markers have been developed to detect specific cell surface components with scanning electron microscopy. Among them bacteriophage T4 (T4) has the most distinctive shape consisting of a hexagonal head and tail. This characteristic shape of T4 makes it possible to survey the cell surface at relatively low magnification and to analyze the site specificity at high magnification. Although precise localization of surface molecules cannot be mapped due to the relatively large size of T4, T4-labeling is most suitable for the analysis of wide surface areas and simultaneous observation of many cells as well as for the analysis of the tissue materials. In this paper, T4-labeling method and technical problems in actual practice including specimen preparation as well as the results obtained are reviewed with particular reference to blood group antigens in bladder tumors.

Antigens, Neoplasm↗

[Double-blind comparison of cefotetan and cefmetazole in complex urinary tract infections].

For the purpose of carrying out an objective evaluation of the clinical efficacy and safety of cefotetan (CTT), a new cephamycin-type injectable antibiotic, in the treatment of complicated urinary tract infections, cefmetazole (CMZ) was employed as the control drug in a comparative study performed by the double-blind method. CTT was administered in a dose of 0.5 g or 1 g, while CMZ was used in a dose of 1 g; both of these drugs were administered by intravenous drip infusion twice a day for 5 days. The total number of treated cases was 393; 105 patients in the CTT 1 g group, 97 patients in the CTT 2 g group, and 96 patients in the CMZ 2 g group. The judgment of the clinical effects of these 3 therapeutic regimens was carried out in accordance with the criteria for evaluation of clinical efficacy of antimicrobial agents on UTI (2nd edition). The results are as follows. With regard to the overall efficacy of the drug treatments, the calculated efficacy rates were 54.3% in the CTT 1 g group, 63.9% in the CTT 2 g group and 52.1% in the CMZ 2 g group. The differences between these efficacy rates were not statistically significant. Regarding the efficacy of the treatments in terms of the bacteriuria, the bacterial cultures were seen to become negative in 40% of the cases in the CTT 1 g group, 54.6% of the CTT 2 g group and 42.7% of the CMZ 2 g group. Again, there were no statistically significant differences between the groups. Concerning the efficacy of the drugs against pyuria, by combining the cases found to be normalized and those seen to show improvement, the improvement rates were calculated to be 41.9% for the CTT 1 g group, 37.1% for the CTT 2 g group, and 37.5% for the CMZ 2 g group. These pyuria improvement rates show no statistically significant differences, respectively. The incidences of occurrence of side effects and laboratory test abnormalities thought to be caused by the drug therapy were as follows; 1.5% and 5.3% in the CTT 1 g group, 1.5% and 3.1% in the CTT 2 g group and 0% and 6.9% in the CMZ 2 g group. There were no significant differences between the groups. Based on the above clinical results, it can be concluded that, in the treatment of complicated urinary tract infections, we can expect CTT to provide the same therapeutic efficacy as CMZ when its dosage is the same or even half thereof. In addition, the safety of CTT is equal to that of CMZ. Therefore, CTT is concluded to be a useful drug.

Adolescent↗

[Assessment of urinary ferritin, CEA and beta 2-MG determinations in patients with urinary tract malignancies].

Ferritin, carcinoembryonic antigen (CEA) and beta 2-microglobulin (beta 2-MG) levels in urine from 45 patients with cancer (4 with renal adenocarcinoma, 7 with renal pelvic and ureteral cancer and 34 with bladder cancer) at various stages were clinically evaluated for their significance as parameter of urinary tract malignancies as compared to urinary fibrin/fibrinogen degradation products (FDP) and urine cytology. Ferritin levels for the poorly-differentiated and advanced stage groups were higher than those for the well-differentiated and early stage groups, and were especially high in 5 of the 7 patients with renal pelvic and ureteral cancer and all of the 7 patients with bladder cancer involving the upper urinary tract. These data suggest that determination of urinary ferritin is useful in the detection of urinary tract cancer involving the upper urinary tract. The upper limits of CEA levels were determined respectively according to white blood cell counts in urine. Although, CEA levels were elevated in the poorly-differentiated group and the advanced stage group compared to the well-differentiated and early stage groups, the values were positive in only 12 out of 52 cases (23.1%). These values seemed to be low compared to other reports. beta 2-MG levels increased significantly in the poorly-differentiated and advanced stage groups. However, most cases in the above groups were complicated with pyelonephritis or renal impairment. It is suggested that the urinary beta 2-MG secretion from cancer itself is not so significant.(ABSTRACT TRUNCATED AT 250 WORDS)

Carcinoembryonic Antigen↗

[Assessment of serum ferritin, CEA, beta 2-MG and PAP determinations in patients with urinary tract malignancies].

Ferritin, carcinoembryonic antigen (CEA), beta 2-microglobulin (beta 2-MG) and prostatic acid phosphatase (PAP) levels in serum from 77 patients with cancer (6 with renal adenocarcinoma, 9 with renal pelvic and ureteral cancer, 29 with bladder cancer and 33 with prostatic cancer) at various stages were clinically evaluated for their significance as a parameter of urinary tract malignancies. Although, ferritin, CEA and beta 2-MG levels in the poorly-differentiated and advanced stage groups of renal adenocarcinoma, renal pelvic and ureteral cancer, and bladder cancer were higher than those in the well-differentiated and early stage groups, those in most cases were within normal ranges. These proteins were not considered suitable for the screening test. Ferritin and beta 2-MG levels increased with advancement of the performance status (P.S.) proposed by Koyama and Saito; however, the latter was affected greatly by renal impairment. In prostatic cancer, PAP and ferritin levels were remarkably high in the poorly-differentiated group (PAP mean +/- S.E.: 57.6 +/- 22.5 ng/ml, ferritin 883 +/- 319 ng/ml) and the advanced stage group (27.2 +/- 10.5 ng/ml, 398 +/- 152 ng/ml) compared to the well-differentiated group (7.87 +/- 3.61 ng/ml, 88.5 +/- 25.8 ng/ml) and the early stage group (2.24 +/- 0.54 ng/ml, 186 +/- 91.7 ng/ml). PAP and ferritin levels of the untreated cases were positive in 10 out of 18 cases (55.6%) and 7 out of 18 cases (38.9%), respectively, and those of the relapsing cases were positive in 4 out of 7 cases (57.1%) and 6 out of 7 cases (85.7%), respectively. However, CEA and beta 2-MG levels were negative in most cases. Furthermore, increments of PAP and ferritin levels, especially that of the ferritin level, were significantly related to advancement of P.S., and high ferritin levels were obtained in all cases of P.S. 3 and 4. Therefore, determination of PAP and ferritin seems to be useful in monitoring prostatic cancer, and the latter to be useful in early detection of relapsing cases.

Acid Phosphatase↗

Primary adenocarcinoma of the renal pelvis. Report of two cases and brief review of literature.

Two cases of primary adenocarcinoma of the renal pelvis are described. One patient was a 64-year-old female who had multiple papillary tumors in the right ureter and renal pelvis. The other was a 57-year-old male who had diffuse infiltrating carcinoma in the left renal pelvis with calculi. In both cases, the lining of the renal pelvis underwent columnar cell metaplasia and the tumor cells showed mucin production. Forty-six cases reported previously are reviewed briefly. The histogenesis of primary adenocarcinoma of the renal pelvis seems to be closely related to metaplasia of transitional epithelium induced by longstanding chronic inflammation or renal calculi in many cases.

Adenocarcinoma↗