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Biomedical subjects

K Ohara

Publications and source records attributed to K Ohara.

At least 235 records · Page 13Linked to original sources
PubMed1990

Secretion of recombinant ribonuclease T1 into the periplasmic space of Escherichia coli with the aid of the signal peptide of alkaline phosphatase.

The ribonuclease T1 (RNase T1) gene was ligated to a synthetic gene for the signal peptide of Escherichia coli alkaline phosphatase. When this fusion gene was expressed in E. coli under the control of the trp promoter, active RNase T1 having the correct N-terminal sequence was secreted into the periplasmic space, indicating that the heterologous signal peptide had been cleaved off correctly. The enzyme could be readily purified from the periplasmic fraction with a yield of 1.8 mg from 1 liter culture. Adopting the same strategy, it was possible to produce a labile mutant of RNase T1 (Glu-58----Ala mutant) in E. coli, the yield of the purified mutant enzyme being 2.0 mg from 1 liter culture.

Alkaline Phosphatase↗
PubMed1990

[A case of double primary malignancy of intracranial germinoma and thymoma controlled by radiotherapy].

We report a case of double primary malignancy, in which intracranial germinoma and thymoma occurred successively and independently. As curative therapies, the former lesion was treated by definitive irradiation and the latter by postoperative irradiation. Excellent local control has been maintained for 79 and 49 months, respectively, since the beginning of the radiotherapy. The accumulated dose to the thoracic spinal cord was 63.5 Gy. No symptoms suggesting the onset of radiation myelopathy, the most critical late radiation injury, have been observed up to now. We also investigated radiobiological effect to the spinal cord assessed by the formulae of CRE and TDF.

Adult↗
PubMed1990

[Radiation tolerance of partially irradiated liver in a multidisciplinary treatment for hepatoma].

Radiation tolerance of the partially irradiated liver was studied in eight patients with primary hepatoma treated by a multimodal approach. Seven patients were treated by transarterial embolization therapy (TAE) with Lipiodol-MMC, and two patients were treated by operation, combined with radiotherapy. Six patients had liver cirrhosis and the other one had renal dysfunction. Respiration-gated irradiation was employed to reduce a treatment volume for seven patients. Radiation portals were carefully tailored using the embolized Lipiodol or a metal clip inserted into the tumor as references. Two or three portals were used for each patient. The treatment volume ranged from 64 to 1400 cm3. The target dose ranged from 50.4 Gy to 81.0 Gy, from 73.5 to 108.6 in TDF. Liver function tests (GOT, GPT, LDH, ALP, ChE and total Bilirubin) were examined for 30 weeks after initiation of irradiation. Three patients showed abnormal value in more than 5 tests. Of these three patients, the hepatic hilum was included in the treatment volume in two, and the tumor progressed during the observation period in two. Leukopenia and thrombopenia were observed, but these values were not below 2000 and 40000/mm3, respectively, although the thrombocyte count before irradiation was below 100000/mm3 in 7 patients. AFP titers decreased after the treatment in six out of seven patients with abnormally elevated pretreatment titer. The survival period after staring irradiation was 6.5 to 25 months. "The volume dose" did not correlate well with the degree of the liver function aggravation.(ABSTRACT TRUNCATED AT 250 WORDS)

Carcinoma, Hepatocellular↗
PubMed1990

Effects of preoperative radiotherapy on rectal cancer. Preliminary report on combining radiation with intratumor injections of peplomycin and bromodeoxyuridine.

Between 1976 and 1983, 61 patients with advanced rectal cancer underwent Miles' operation at the authors' institution. All lesions were located 10 cm or less from the anal verge. Of these patients, 25 were treated by surgery alone and 36 were given preoperative radiotherapy. The total dose was 42.6 Gy, (30.6 Gy [1.8 Gy/fr x 5/week]) delivered to the entire pelvis plus an additional 12 Gy (3.0 Gy/fr x 4/week) delivered to the primary tumor. Of 36 patients, 21 were administered intratumor injections of peplomycin and bromodeoxyuridine at the time of boost radiation and 15 were treated without intratumor injections. During the follow-up period (3 to 9 years), in the groups of patients who underwent radiation, there was only one local failure (2.8 percent). In contrast, in the group of patients treated by surgery alone, eight local failures occurred (32 percent). The intratumor injection significantly enhanced the effect of radiation on tumor regression. The incidence of positive lymph nodes was higher in patients in the surgery alone group than it was in the groups treated with radiation. There was no difference in the rate of distant metastasis among the three treatment groups. The five-year survival rate for the radiation with intratumor injection group, radiation alone group, and surgery alone group, was 77.8, 69.2, and 56.0 percent, respectively. No severe complication was experienced.

Adenocarcinoma↗
PubMed1990

Location in muscarinic acetylcholine receptors of sites for [3H]propylbenzilylcholine mustard binding and for phosphorylation with protein kinase C.

Muscarinic acetylcholine receptors purified from porcine cerebra or atria were covalently labeled with [3H]propylbenzilylcholine mustard ([3H]PrBCM), and then the labeled receptors were subjected to limited hydrolysis with trypsin, V8 protease, and lysyl endopeptidase, followed by analysis involving sodium dodecyl sulfate-polyacrylamide gel electrophoresis, fluorography, autoradiography, or immunostaining. The labeled peptides were located on the basis of their reactivity with antibodies raised against three synthetic peptides with partial sequences of the m1 or m2 receptor, and of their sensitivity to endoglycosidase F, which was taken as evidence that they contain glycosylation sites near the N terminus. The [3H]PrBCM-binding site in both cerebral and atrial receptors was found to be located between the N terminus and the second intracellular loop, because the size of the smallest deglycosylated peptide that contained both the [3H]PrBCM-binding and glycosylation sites was approximately 16 kDa. Cerebral receptors were 32P-phosphorylated with protein kinase C, and the major phosphorylation sites in cerebral muscarinic receptors were found to be located in a C-terminal segment including a part of the third intracellular loop, because a 32P-labeled peptide of 12-14 kDa reacted with anti-(m1 C-terminal peptide) antiserum. The presence of an intramolecular disulfide bond, probably between Cys 98 and Cys 178 in the first and second extracellular loops, respectively, was suggested by the finding that a peptide of approximately 17 kDa containing the [3H]PrBCM-binding site, but not the glycosylation sites, was partly converted to a peptide of approximately 12 kDa on treatment with beta-mercaptoethanol.

Animals↗
PubMed1990

[Therapeutic evaluation of combination therapy using C-425 and antibiotics in severe bacterial infections--a double blind group comparative study. The C-425 Research Group for Infectious Comparative Study].

Clinical usefulness of C-425, a native human immunoglobulin liquid preparation for intravenous injection, was studied in combination with antibiotics in severe bacterial infections in a double blind group comparison using an alkylated human immunoglobulin liquid preparation (Polyglobin, A.gamma G) as a reference drug. The following results were obtained: 1. C-425 or A.gamma G was administered to a total of 117 patients, of whom 89 patients, 45 in C-425 group and 44 in A.gamma G group, were included in the present analysis of efficacy and usefulness. Analysis of safety of the drugs included a total of 113 patients, 58 in C-425 group and 55 in A.gamma G group. 2. Efficacy and usefulness were graded according to a visual analog scale (VAS). 3. Mean efficacy values with standard deviations of VAS value were calculated at 52.0 +/- 34.9 for the C-425 group, and 47.2 +/- 34.8 for the A.gamma G group. The respective medians were 59.0 and 61.0. The Mann-Whitney U-test revealed no significant differences between the two groups. When those with VAS values of 50 or above were regarded as cases of effective treatment, the efficacy rates of the two groups were also practically comparable. 4. Side effects were not observed in either drug group. 5. Mean usefulness values with standard deviations were 52.3 +/- 34.9 for the C-425 group, and 47.9 +/- 35.0 for the A.gamma G group. The respective medians were 60.0 and 61.0. The Mann-Whitney U-test revealed no significant differences between the two groups. When the cases with VAS values of 50 or above were regarded as cases of useful treatment, there were no significant differences in the utility rates between the two groups. From these results, C-425 was considered to be useful for treating severe bacterial infections when used combined with antibiotics.

Adolescent↗
PubMed1990

Possible involvement of lymphocyte activating factor (LAF) as an endogenous pyrogen in fever induced by the cell wall skeleton of Nocardia rubra (N-CWS).

We investigated whether interleukin-1 (IL-1) acts as an endogenous pyrogen (EP) on the fever caused by the cell wall skeleton of Nocardia rubra (N-CWS) in guinea pigs. IL-1 activity was expressed as potency of lymphocyte activating factor (LAF). When guinea pig peritoneal macrophages were pulse-stimulated with N-CWS (1-100 micrograms/ml), dose-dependent LAF activity was detected in the supernatants after culture for 4 h. Gel filtration of the culture supernatants on Sephadex G-200 showed that the fractions with LAF activity were not the same as those with cytotoxic activity for L-929 cells, which was measured as an index of tumor necrosis factor (TNF) in parallel with LAF activity. Pyretic activity was detected both in the fractions with LAF activity and in those with cytotoxic activity for L-929 cells. Furthermore, when these macrophages were pulse-stimulated again, this time with the supernatant obtained from macrophages previously pulse-stimulated with N-CWS, LAF and cytotoxic activity for L-929 cells continued to be released from the macrophages. We suggest that IL-1 might be a possible EP in the process of fever elicited by N-CWS, and that such an EP stimulates the macrophages to release further IL-1 or TNF. The resultant long-lasting fever would thus be caused by the continuous release of an EP.

Animals↗
PubMed1990

The role of preoperative radiotherapy for invasive thymoma.

Six patients with large invasive thymomas were treated by preoperative irradiation with 12 to 20 Gy before total or partial resection of the tumor. The responses of these 6 thymomas were estimated on the chest radiograms as follows; complete response in 2 patients, partial response in 3 and no response in one. Although the clinical responses varied, the surgical specimens of all the tumors pronounced severe fibrosis, probably not related to irradiation, and necrotic foci with a few viable tumor cells. Total resection of the thymoma was performed in 3 patients and subtotal resection in 3. Adhered or involved surrounding tissues such as the pericardium, pleura and/or veins were also resected in most patients. Preoperative radiotherapy facilitated total or subtotal resection of the invasive thymoma mass by reducing the tumor volume.

Adult↗
PubMed1990

[Correlation between total aqueous protein concentrations and photon counts in rabbits].

We studied the correlation between photon counts of the aqueous flare and total aqueous protein concentrations in rabbit eyes. After mydriasis, a predetermined volume of the aqueous humor was aspirated and photon counts of the secondary aqueous was measured using a laser flare-cell meter. In vitro measurements of total protein concentrations showed that step-wise changes in withdrawal volume ranging from 50 to 200 microliters induced corresponding rises of the total protein concentrations in the secondary aqueous, with the mean total protein concentrations ranging from 220 to 1980 mg/dl. A ratio of albumin to globulin concentrations (A/G) ranged from 1.0 to 3.6, but they did not show any significant correlation with the aqueous total protein concentrations. The mean photon counts in the secondary aqueous ranged from 40 to 343/msec. A statistical analysis showed that photon counts correlated well with the total protein concentrations. The linear regression equation was X = Y1.07 x 3.33 where X and Y indicate protein concentrations and photon counts, respectively (r = 0.92, p less than 0.001). The regression equation might be used to estimate the total aqueous protein concentrations in laser flare-cell measurements in vivo. The variation of A/G ratio affected the photon count values, and the total protein concentration might be within 3/2 and 1/2 of the estimated value.

Animals↗
PubMed1990

[Effects of intra-aortic balloon pumping on mitral flow dynamics after aortocoronary bypass surgery].

Improvement in left ventricular function following intra-aortic balloon pumping (IABP) in 15 patients (aged 51 to 86 years) after coronary artery bypass grafting was evaluated. Using transesophageal atrial echocardiography, the mitral flow velocity integrals in the rapid filling phase (IntR) and in the contraction phase (IntA) were measured from transmitral flow patterns, and the sum of IntR and IntA (IntR + IntA), and the ratios of IntA to IntR (IntA/IntR) were calculated for ON and OFF states of balloon pumping (IABP OFF test). The same parameters were determined during 1:2 assist balloon pumping (IABP 1:2 test); the cardiac cycle with balloon assist was defined as "ON", and that without balloon assist as "OFF". 1. IABP OFF test: IABP increased IntR from 6.4 +/- 1.6 cm to 7.6 +/- 1.9 cm (p less than 0.01), suggesting that a decreased afterload improves left ventricular relaxation. IntA did not change with balloon assist (ON 3.5 +/- 1.2 cm, OFF 3.7 +/- 1.2 cm). IntR + IntA increased from 10.0 +/- 2.0 cm to 11.1 +/- 2.4 cm during IABP (p less than 0.01). IABP reduced the IntA/IntR from 0.62 +/- 0.25 to 0.50 +/- 0.20 (p less than 0.01). The increment in the IntA/IntR without IABP suggests that impaired diastolic filling of the left ventricle due to an increased afterload may be compensated for by enhanced left atrial contraction.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1990

[Late results of coronary bypass grafting in patients with concomitant multifocal arteriosclerotic vascular diseases].

Late results of coronary bypass graftings (CABG) in the patients with multifocal arteriosclerotic vascular diseases were reviewed. Between September 1978 and July 1989, 819 consecutive patients underwent CABG. There were 693 males and 126 females, mean ages 58 +/- 8.5 years. Of 819 consecutive patients underwent CABG, 95 patients had the coexistence of multifocal atherosclerosis (Group A). Seventy two patients had aortoiliac or femoropopliteal disease, and 29 patients had aortic aneurysm. The remaining 724 patients had no coexistence of multifocal atherosclerosis (Group B). The mean follow-up periods was 4.0 +/- 2.1 years, and the follow-up ratio was 99.4%. The 5- and 10-year survival rates were 80% and 52% in group A, and 92% and 82% in Group B, respectively. The 5- and 10-year free ratio from cardiac events were 79% and 42% in Group A, and 85% and 61% in Group B, respectively. The 5- and 10-year free ratio from noncardiac events were 53% and 38% in Group A, and 85% and 76% in Group B, respectively. The results showed that the coexistence of multifocal atherosclerotic vascular disease in patients underwent CABG significantly increase the ratio of noncardiac and cardiac events, and decreased life expectancy.

Aged↗
PubMed1990

[Weekly CHOP chemotherapy in the treatment of intermediate-grade non-Hodgkin's lymphomas--cooperative group study by seven institutes].

Between 1985 and 1988, 49 previously untreated patients with intermediate-grade non-Hodgkin's lymphoma (LSG classification large cell 35 including 11 large cell immunoblastic by Working Formulation, medium-sized cell 7, mixed 7) were treated with the Weekly CHOP regimen (three successive weekly administration of cyclophosphamide, doxorubicin, vincristine and prednisolone) as a cooperative group study by seven institutes (Nagoya Lymphoma Study Group). Complete remission was achieved in 63.3% with Weekly CHOP alone and finally in 79.6% after the addition of radiotherapy and/or combination chemotherapies including etoposide, methotrexate, procarbazine, bleomycin. Patients with T cell phenotype, high grade PS and the presence of bulky mass had significantly lower rates of CR. After a median follow-up 36 months Kaplan-Meier estimates showed that overall survival was 60.4%, disease-free survival 51.4% and relapse-free survival 64.6%. The major toxicities were alopecia, leukopenia, infection, neuropathy and gastrointestinal symptoms. No treatment-related deaths were observed. Survival was adversely affected by high LDH level, poor PS, T cell phenotype, the presence of B symptoms and the bulky mass. But these characteristics gave no significant effects on relapse rate and relapse-free survival. Thus, Weekly CHOP is an effective treatment for intermediate-grade NHL.

Adolescent↗
PubMed1990

[Clinical results of open heart surgery within 2 weeks after cardiogenic embolic stroke].

Fourteen patients, 5 with infective valvular disease (IVD), 7 with non-infective valvular disease (NVD) and 3 with LA myxoma, underwent open heart surgery within 2 weeks after cardiogenic embolic stroke because of uncontrolled heart failure or recurrent embolism. Fifty percent of patients experienced a second embolism within 2 weeks of the initial stroke. Preoperative brain CT revealed no hemorrhagic infarction in all patients. However, in 3 of 5 patients with IVD, who had large brain infarction, one patient died from massive brain edema and two patients from severe brain hemorrhage. The other 2 patients with IVD, who had small infarction, and the remaining 7 patients with NVD and LA myxoma, even having large or small infarction, recovered without any complications. From these results, we concluded that 1) Open heart surgery within 2 weeks after initial stroke was safe in patients with no brain infarction and small non-hemorrhagic infarction, 2) Patients with IVD should be treated surgically before embolic stroke, because mortality rate was so high even in patients with non-hemorrhagic infarction.

Adult↗