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T Oka

Publications and source records attributed to T Oka.

At least 1,153 records · Page 64Linked to original sources
PubMed1986

Intravascular bronchiolo-alveolar tumor (IVBAT). Case report with the immunological analysis.

A case of intravascular bronchiolo-alveolar tumor, a rare lung neoplasm which is often found among women, is reported. Our ultrastructural findings and existence of factor VIII-related antigen support the hypothesis of vascular origin. The relationship between IVBAT and epithelioid hemangioendothelioma is discussed. We also examined whether immunological abnormalities existed in our patient, because tuberculin test gave negative result in many cases reported previously and our case. No specific immunological change was found except for negative tuberculin test.

Adult↗
PubMed1986

Analysis of receptors, cell surface antigens, and proteins in human melanoma cell lines resistant to human recombinant beta- or gamma-interferon.

We studied the mechanisms of resistance to interferon (IFN) in two human melanoma cell lines, SK-MEL-28/beta cells resistant to human recombinant beta-interferon (ReIFN-beta) and SK-MEL-28/gamma cells resistant to human recombinant gamma-interferon (ReIFN-gamma). SK-MEL-28/beta cells were resistant to both ReIFN-beta and IFN-alpha, but not ReIFN-gamma or natural gamma-interferon (IFN-gamma), and SK-MEL-28/gamma cells were resistant to both ReIFN-gamma and IFN-gamma, but not ReIFN-beta or IFN-alpha. SK-MEL-28/s cells, sensitive to both ReIFN-beta and ReIFN-gamma, had receptors for ReIFN-beta and ReIFN-gamma. Furthermore ReIFN-beta and IFN-alpha shared the common receptors as judged by competition assays, while the receptors for ReIFN-gamma were independent in SK-MEL-28/s cells. The Kd values of binding of both IFNs to SK-MEL-28/beta or SK-MEL-28/gamma cells were essentially equivalent to those to SK-MEL-28/s cells. Both labeled IFNs were internalized rapidly into all cell lines at 37 degrees C. No significant difference in internalization was found between IFN-sensitive and -resistant cells. Each cell line expressed HLA-AB and Mr 97,000 protein antigens, the expressions of which were enhanced by ReIFN-beta and ReIFN-gamma. Partial resistance to the enhancement of both antigens by both IFNs was seen in the resistant cells. Finally ReIFN-gamma, but not ReIFN-beta, induced a Mr 56,000 protein in SK-MEL-28/s cells. This effect of ReIFN-gamma was also detected in SK-MEL-28/beta cells, but not SK-MEL-28/gamma cells. These results provide some information concerning the nature of IFN-resistant cells. The receptors had no significant correlation with the resistance, while the expression of HLA-AB or Mr 97,000 protein antigens or the induction of proteins had some correlation with the resistance.

Antigens, Neoplasm↗
PubMed1986

Inactivation of [Leu5]-enkephalin in three isolated preparations: relative importance of aminopeptidase, endopeptidase-24.11 and peptidyl dipeptidase A.

Enkephalin had been shown to be almost exclusively hydrolyzed by three peptidases in the previous studies. In the present investigation, the relative importance of three enzymes in the inactivation of [Leu5]-enkephalin was examined in three isolated preparations. Results showed that amastatin-sensitive aminopeptidase played the greatest role in both guinea-pig ileum and rat vas deferens while it played the similar role to either phosphoramdidon-sensitive endopeptidase-24.11 or captopril-sensitive peptidyl dipeptidase A in mouse vas deferens.

Animals↗
PubMed1986

Characteristics of opioid receptors in guinea-pig cerebellum and human placenta.

Characteristics of opioid receptors were examined in guinea-pig cerebellum and human placental membrane preparations. Two binding sites for [3H]-ethylketocyclazocine ([3H]-EKCZ) were found in guinea-pig cerebellum membranes whereas only one binding site was detected in human placental membranes. The potencies of kappa opioid agonists were decreased in competing with the binding of [3H]-naloxone to guinea-pig cerebellum membranes or human placental membranes by 5'-guanylylimidodiphosphate (Gpp(NH)P) and sodium. These results suggest that there may be true kappa receptors in human placenta and that kappa receptors in both preparations may couple with the adenylate cyclase system.

Animals↗
PubMed1986

Cleavage lines of the skin.

Detailed investigation on cleavage lines over the entire area of the body was undertaken in 3 each of male and female cadavers. The directions of cleavage lines showed sex and individual differences. Minute comparison of the diagrams obtained in this study with earlier diagrams revealed the presence of delicate differences in the directions of cleavage lines. Microscopical evaluation of cleavage lines showed that in the regions where cleavage lines were linearly arranged, collagen fibers were regularly arranged in a uniform direction, conforming to the direction of cleavage lines from the shallow reticular layer immediately below the papillary layers to the inner reticular layer where sebaceous and sweat glands existed and that in the regions where cleavage lines were ramified, collagen fibers in these layers lacked directional regularity. The morphology of cleavage lines were considered most influenced by collagen fibers in the epidermal reticular layers from their shallow layers immediately below the papillary layers to the layer where sebaceous and sweat glands existed.

Adult↗
PubMed1986

Enzymatic semisynthesis of [LeuB30] insulin.

Experimental conditions for the preparation of [LeuB30] insulin by coupling of des-AlaB30 insulin with Leu-OBu(t) were determined using Achromobacter protease I and trypsin as catalysts. Successful coupling required a large excess of the amine component (0.8 M), a high concentration of organic cosolvent (35-50%) and neutral pH of the reaction mixture. The coupling yield of Achromobacter protease I after 24 h at 37 degrees C was almost the same or a little higher than that at 25 degrees C. With trypsin, the coupling yield at 37 degrees C after 24 h was considerably lower than at 25 degrees C. This was partly ascribed to the difference in concentration of organic cosolvent at 37 degrees C and 25 degrees C; 35% and 50%, respectively, or possibly of enzyme stability at these temperatures. The maximum product yield was about 90% with both enzymes under optimal conditions. A preparative scale experiment was performed with Achromobacter protease I; the yield of [LeuB30] insulin was 51% using porcine insulin as the starting material. This semisynthetic insulin was identified by HPLC and amino acid analysis. No difference was observed in CD spectra between [LeuB30] insulin and human insulin.

Alcaligenes↗
PubMed1986

[A pharmacokinetic and clinical evaluation of ceftazidime in neonates and premature infants. A study of ceftazidime in the perinatal co-research group].

Ceftazidime (CAZ) was evaluated for its pharmacokinetics and clinical usefulness in neonates and premature infants. The results obtained were summarized below. Following intravenous injection of CAZ 10 or 20 mg/kg to neonates and premature infants, dose response was observed in serum concentrations ranging from 5.1 to 21.9 micrograms/ml at 6 hours after the injection. The serum half-life tended to be longer in premature infants than in neonates; the half-life being longer for an infant with lower day-age. Urinary recovery rates during the first 6 hours after single administrations of 10 mg/kg of CAZ tended to be higher in neonates than in premature infants, and higher rates were observed in older infants. However, no noticeable difference was observed after the administration of CAZ 20 mg/kg. Clinical efficacy was evaluated in 99 neonates and 55 premature infants (156 infections), daily doses ranging from 21.1 to 246.4 mg/kg. Out of 105 cases of common infections, mainly 44 cases with causative organisms identified (including 17 of sepsis, 7 of pneumonia, 4 of purulent meningitis, 11 of urinary tract infections) were examined for the clinical efficacy. The efficacy of CAZ was excellent in 21, good in 18, fair in 1 and poor in 4, with the efficacy rate of 88.6%. In the remaining 61 cases, i.e., 37 with causative organisms unknown and 24 with signs of intrauterine infections, the efficacy rate was 95.1%. Other than these cases, additional 51 cases were given CAZ solely for prophylaxis of infections, and the results were found satisfactory. On the whole, clinical efficacy rate of CAZ was 94.9% in 156 cases. Out of the 44 cases examined for bacteriological responses, 38 were evaluated as 'eradicated', 3 'persisted' and 3 'unknown' with eradication rate of 92.7%. Replacement of organisms (superinfection) was observed in 3 cases. Out of 179 cases in which adverse effects were assessable, adverse effects were observed in a total of 4 cases (2.2%), i.e., 3 cases of diarrhea (1.7%) and 1 case of rash (0.6%), and abnormal laboratory findings were observed in a total of 14 cases (7.8%), i.e., increase in eosinophiles count in 8 (4.5%), elevation of GOT in 3 (1.7%), increase in platelet, elevation of GOT . GPT, and elevation of GOT . GPT . BUN in 1 case each (0.6%). None of them were severe and they were transient. Elevations of bilirubin and cases of positive PIVKA II associated with CAZ were not observed.(ABSTRACT TRUNCATED AT 400 WORDS)

Bacterial Infections↗
PubMed1986

[Clinical and pharmacokinetic evaluation of ceftazidime in neonates and young infants].

Seventeen newborn and young infants including 6 premature infants were treated with ceftazidime (CAZ) and the clinical efficacy and side effects were evaluated. Ages of the patients ranged from zero to 55 days, and their body weights ranged from 1.35 to 3.87 kg. Doses of CAZ ranged 10-50 mg/kg every 6 to 12 hours for 3 to 14 days. Twelve infants with infections including meningitis, sepsis, pneumonia and urinary tract infections, were considered to have responded to the CAZ treatment. Among them, results were excellent in 2, good in 9 and fair in 1 patient. The drug was well tolerated, but 1 had diarrhea and 3 patients had eosinophilia among the 17 patients. The pharmacokinetics of CAZ was studied in 22 patients including 11 premature infants. Their ages ranged from 1 to 60 days, and body weights ranged from 0.85 to 3.96 kg. Serum concentrations in 7 patients ranged from 24.2-38.5 micrograms/ml at 30 minutes after single doses of 10 mg/kg intravenous bolus injections and 4.36-12.4 micrograms/ml at 6 hours. Mean elimination half-lives of the drug were 3.20 hours in 2 patients under 7 days of age and 2.31 hours in 5 patients from 7 days of age or older. In 8 patients, serum concentrations ranged 32.6-57.9 micrograms/ml at 30 minutes and 8.10-20.7 micrograms/ml at 6 hours after single doses of 20 mg/kg. Elimination half-lives were 3.53 hours in 4 patients under 7 days of age and 2.79 hours in 4 patients from 7 days of age or older.(ABSTRACT TRUNCATED AT 250 WORDS)

Bacterial Infections↗
PubMed1986

[The effects of serum from tumor-bearing mice on mitogen-induced blastogenesis of normal spleen cells].

In order to detect the serum immunosuppressive factors of tumor bearer, the effects of normal C3H/He mice serum (NMS), serum from methylcholanthrene induced fibrosarcoma bearing mice (F4w serum) and sera fractionated by high performance liquid chromatography (HPLC) using anion exchange column were examined on mitogen-induced blastogenesis of normal murine spleen cells (Nspc). The addition of 5% of NMS suppressed the blastogenesis of Nspc. Less than 0.6% of F4w serum suppressed the blastogenesis. NMS was applied to HPLC and was separated to four peaks (A,B,C,D). In HPLC pattern of F4w serum, peak B was higher than that of NMS and new peak (E) was observed next to peak D. Peak D of NMS suppressed the blastogenesis. Not peak D but peak E of F4w serum suppressed the blastogenesis. The properties of those blastogenesis-suppressive fractions were discussed.

Animals↗