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Biomedical subjects

T Ono

Publications and source records attributed to T Ono.

At least 667 records · Page 37Linked to original sources
PubMed1994

Expression and localization of the mRNA for DNA (cytosine-5)- methyltransferase in mouse seminiferous tubules.

DNA (cytosine-5)-methyltransferase (DNA MTase) is the only enzyme known to be involved in the methylation of mammalian DNA. Although the expression of DNA MTase gene is abundant in the testis, little is known about the role of this enzyme during spermatogenesis. We examined the distribution of DNA MTase mRNA in mouse testis by in situ hybridization histochemistry with an oligonucleotide probe. The mRNA signal was observed in the seminiferous tubules and was localized predominantly in spermatogonia and spermatocytes, particularly during the earlier steps of meiotic prophase I, with maximal intensity in the early pachytene cells. These results suggest some significant role for DNA MTase in spermatogenesis.

Animals↗
PubMed1994

Structure-activity relationship study of 6-O-methylerythromycin 9-O-substituted oxime derivatives.

In order to develop new-generation macrolide antibiotics active against erythromycin (EM)-resistant strains, a series of 6-O-methyl EM 9-O-substituted oxime derivatives was synthesized and evaluated for antibacterial activity against EM-resistant (S. aureus J-109) and susceptible (S. aureus 209P) strains. To understand how substituents affect the biological activity, the quantitative structure-activity relationships (QSAR) was analyzed using the Hansch-Fujita method. With the EM-resistant strain, the positive coefficient for log P may indicate that higher hydrophobicity of molecules is favorable for antibacterial activity. The negative coefficients of the Sterimol parameters L, B1, and B5 may indicate that long, bulky substituents are unfavorable. With the EM-susceptible strain, the negative coefficient for log P may indicate that hydrophilicity is important for antibacterial activity. A short substituent is also required to improve the activity. Based on the QSAR model, a derivative (87) having an anthracenylmethyl moiety was synthesized to reinforce and confirm the correlation. The activity of 87 against the EM-resistant strain was significant. In QSARs of 6-O-methyl EM-A 9-O-substituted oxime derivatives, the difference of the contribution of log P to the antibacterial activity between EM-resistant and susceptible strains was clearly recognized.

Anti-Bacterial Agents↗
PubMed1994

Structure of hardwood xylan and specificity of Streptomyces beta-xylanase toward the xylan.

Three kinds of xylo-oligosaccharides having structures of 3(2)-beta-xylosylxylobiose, 3(2)-beta-xylobiosylxylobiose, and 2(2)-beta-xylobiosyl-xylobiose were isolated from an enzymatic hydrolysate of hardwood xylan with Streptomyces beta-xylanase. The structures suggest that the hardwood xylan has both (1-->2)- and (1-->3)-beta-D-xylopyranosyl linkages in the structure, and the specificity of Streptomyces beta-xylanase toward the stubs is similar to that toward glucuronic acid stubs, but is somewhat different from that toward arabinose and xylosylarabinose stubs.

Carbohydrate Conformation↗
PubMed1994

Allergens of the house dust mite, Dermatophagoides pteronyssinus, in patients with mite allergic rhinitis: a clinical investigation by intracutaneous skin tests and nasal provocation tests.

To determine the allergens of mite allergic rhinitis, we studied 31 patients with mite allergic rhinitis by skin tests and nasal provocation tests (15 for skin and 16 for nasal tests) using 6 fractions of Dermatophagoides pteronyssinus (Dp) extract differing in molecular weights (15, 25, 32, 53, 95 and 190 kDMW). In skin testing, patients showed intense positive reactions to the fractions of 15, 25, 32, 95 and 190 kDMW, among which the most patients showed positive reactions to the fractions of 15 and 25 kDMW. Significant differences were found in patients' positive reactivity among each fraction and between low (15 and 25 kD) and high (95 and 190 kD) molecular weight fractions as well. In nasal provocation tests, patients showed intense positive reactions to the fractions of 15, 32, 53 and 95 kDMW, especially to the fractions of 15 and 95 kDMW. Furthermore, the insidence of positive reactions to the 15 kDMW fraction was significantly higher than that to any other fraction in the skin tests (P < 0.05). From these results, the low molecular weight fraction, 15 kDMW, is considered to be the main allergen of this mite and the high molecular weight fractions, 95 and 190 kDMW, may also be considered to be allergens of this mite.

Adolescent↗
PubMed1994

Radiation therapy of adult T-cell leukemia.

Between January, 1983 and December, 1991, 30 adult patients with T-cell leukemia (ATL) and lymph node or skin lesions resistant to chemotherapy were treated by irradiation. Thirty Gy of high energy x-rays, 60Co gamma rays or electrons was delivered to 22 lymph node lesions in 17 patients, for focal cutaneous lesions in 6 patients, and as total skin irradiation in 7 patients. Irradiation therapy was effective in all patients with skin lesions and in 12 of 17 patients with lymph node lesions. Symptoms such as pain or itching diminished in all cases and no severe side effects were observed. Radiation therapy thus achieved good control of ATL associated focal lesions resistant to chemotherapy. Even if the prognosis of ATL is poor, radiation therapy should be considered as a palliative therapy.

Adult↗
PubMed1994

Uptake of remnant like particles (RLP) in diabetic patients from mouse peritoneal macrophages.

To investigate whether the remnant like particles (RLP), separated from serum by an immunoaffinity gel mixture of anti-apo B-100 and apo A-I monoclonal antibodies, are relevant to the initiation or progression of atherosclerosis, the incorporation of RLP into mouse macrophages was studied using histochemical and biochemical techniques. Remnant lipoproteins such as RLP are reported to contain a large quantity of chyloniron and very low density lipoprotein (VLDL) remnants, especially in diabetic patients. The RLP separated from the sera of 32 diabetic patients were found to be predominantly taken up into macrophages harvested from mouse abdominal cavities by the staining method applying oil red O. Furthermore, using 14C-oleate to prove the uptake of lipoproteins by macrophages, the uptake of RLP-VLDL, a VLDL fraction of RLP by ultracentrifugation, was the next highest to that of the oxidized LDL, which suggests that RLP-VLDL is also aggressively taken up by macrophages. The degree of uptake of RLP-VLDL by macrophages was positively correlated with HbA1c of these diabetic patients (r = 0.556, p < 0.01), irrespective of the ways of the treatment of diabetes. In conclusion, RLP can contribute to the foaming of macrophages, which in turn may explain the acceleration of atherosclerosis in diabetic patients.

Aged↗
PubMed1994

[An experimental study of the efficacy of platelet aggregating inhibitor on hepatic metastasis].

To investigate whether OKY-046 (an inhibitor of thromboxane A2 synthetase) and TCV-309 (an antagonist of platelet activating factor) can inhibit VX-2 tumor metastasis, the following studies were performed. Study 1 animal experiment: VX-2 tumors were inoculated and OKY-046 or TCV-309 was administered into the portal vein with or without combination of adriamycin (ADR). The number of tumor nodules on the whole liver surface were counted at three weeks after tumor cells inoculation. The combination of OKY-046 and ADR significantly reduced the number of tumor nodules compared to control and TCV-309. Study 2 in vitro experiment: Human breast cancer cells (MCF-7) overlayed confluently cultured human endothelial cells (HUVEC) in vitro with or without OKY-046 and TCV-309 for 3 days; MCF-7 cells invaded the endothelial cells and built-up colonies. The number of colonies built up were counted. OKY-046 significantly decreased the number of colony formations, but TCV-309 did not. These results suggest that OKY-046 has an inhibitory effect on extravasation of tumor cells.

Animals↗
PubMed1994

[Efficacy of intrahepatic arterial chemotherapy to prevent recurrence of residual liver in metastatic liver cancer patients after hepatectomy].

Five-year overall survival rates in 17 cases who underwent the hepatectomy for metastatic liver cancer from digestive tract averaged 43%. Postoperative intrahepatic arterial infusion in combination with Farmorubicin and 5-FU was performed in 9 cases (i.a group). Survival and recurrence rate on cases (i.a group) were compared with that of 8 cases without chemotherapy (control group). The 5-year survival rate was superior in the i.a group to that in the control group. There was no residual liver recurrence in the i.a group, but two cases had recurrence in the residual liver in the control group. These results suggest that the post-hepatectomized intrahepatic arterial infusion of anticancer drugs is useful to prevent recurrence in the residual liver and may prolong the survival time of patients with metastatic liver cancer from GI tract.

Aged↗
PubMed1994

[Analysis of cases with liver abscess following transcatheter arterial chemoembolization (TAE) for malignant hepatic tumors].

A total of 182 TAE procedures were carried out in 98 patients with malignant hepatic tumors during the last five years. Liver abscess following TAE occurred in 3 cases (3.1%) and in 3 procedures (1.7%). All cases were discharged after successful percutaneous transhepatic abscess drainage. One case had hepatocellular carcinoma. Another case had undergone total gastrectomy and esophagojejunostomy with Roux-Y reconstruction for gastric leiomyosarcoma. The other had undergone right hemicolectomy and pancreatoduodenectomy for colon cancers and carcinoma of the ampulla of Vater. Communication between the abscess and the intrahepatic bile duct was recognized in 2 cases. In the abscess culture, E. coli and Citrobacter freundii were detected. These results suggest the major factor leading to abscess formation is biliary infection. Therefore, a previous bilio-enteric anastomosis should be regarded as a risk factor for liver abscess following TAE.

Aged↗
PubMed1994

Effects of an anti-platelet drug (dilazep) in IgA nephropathy: comparison of clinical effects with renal biopsy findings.

To investigate renal biopsy findings arising in response to treatment with an anti-platelet drug in IgA nephropathy, 46 patients were treated with dilazep dihydrochloride (Dilazep), and a retrospective comparison was performed between the clinical effects and renal biopsy findings. After 6 months of treatment, 18 patients (39%) were judged to be improved if their proteinuria was ameliorated by a 25% or greater decrease with improved or persistent renal function. The group of improved patients exhibited mean decreased levels of urinary proteins in the range from 1.9 to 0.8 g/day after treatment (p < 0.01). By contrast, the unimproved group showed increased urinary proteins in the range from 1.2 to 2.0 g/day (p < 0.05). The improved group showed histological findings with fewer glomeruli exhibiting sclerosis and/or cellular crescents, with a lesser increase in mesangial matrix and with smaller tubulo-interstitial lesions than the unimproved group. By immunofluorescence, the improved group was found to have smaller amounts of glomerular IgA and IgG deposits. These findings suggest that an anti-proteinuric effect of Dilazep administration can be expected in patients with IgA nephropathy with relatively mild glomerulo-sclerotic lesions.

Adult↗
PubMed1994

[Computed tomography findings of malignant pleural mesothelioma].

Computed tomography (CT) findings were assessed in 7 patients with malignant mesothelioma. CT findings were also reviewed in 9 patients with lung cancer and pleuritis carcinomatosa and in 11 patients with tuberculous pleuritis. Five patients with malignant mesothelioma underwent CT scans twice, on admission and from 1 to 7 months after admission. Tuberculous pleuritis could be distinguished from pleuritis carcinomatosa and malignant mesothelioma by the presence or absence of pleural nodularity and chest wall invasion. Although it was difficult to identify specific CT features clearly distinguishing malignant mesothelioma from pleuritis carcinomatosa, characteristic findings of malignant mesothelioma appeared to include the rapid development and progression of pleural rind and a tendency to spread directly into the chest wall. We divided the pleura into the four regions; upper anterior, upper posterior, lower anterior and lower posterior regions. Pleural changes were more frequently seen in the lower pleural regions than in the upper pleural regions, in malignant mesothelioma.

Aged↗
PubMed1994

[Induction of anesthesia with midazolam and thiamylal].

Midazolam has a slow onset of action, while thiamylal causes pain on injection and circulatory changes. To compensate for these drawbacks, the usefulness of a combination of midazolam and thiamylal in anesthesia induction was studied. The combination method was compared to the induction with single use of thiamylal in 40 patients (20 patients in each group). The combination of 0.2 mg.kg-1 of midazolam and 1.9 mg.kg-1 of thiamylal showed a shorter onset of action than the 4-5 mg.kg-1 of thiamylal. Pain on injection was observed in 5 cases of thiamylal group but in no cases of combination group. The changes in blood pressure, heart rate and rate pressure product were obviously smaller in combination group than in thiamylal group. Although the recovery time from anesthesia of combination group (13.2 minutes) was longer than that of thiamylal group (10.5 minutes), this was not clinically important. It is concluded that anesthesia induction with the combination of midazolam 0.2 mg.kg-1 and thiamylal 1.9 mg.kg-1 is more useful than that of thiamylal alone.

Abdomen↗