Search PubMed⌕ Search

Biomedical subjects

M Takayama

Publications and source records attributed to M Takayama.

At least 217 records · Page 12Linked to original sources

Formation of varicella-zoster virus antigens in infected Vero cells.

The formation of varicella-zoster (V-Z) virus-associated antigens was studied in V-Z virus-infected Vero cells by means of indirect immunofluorescence. Early antigen (EA) was first detected inside V-Z virus-infected Vero cells 4 to 6 hr after infection, whereas surface membrane antigen (SMA) was expressed on the outer surface of infected cells 2 to 3 hr later than EA, and intranuclear late antigen (LA) was detected several hours later than SMA antigen. EA expression was not inhibited by cytosine arabinoside (Ara-C) treatment, whereas LA formation was completely blocked by Ara-C. The presence of two components of SMA early SMA (ESMA) and late SMA (LSMA), was suggested by this difference in susceptibility to Ara-C. The formation of all viral antigens, EA, SMA, and LA, was blocked by inhibitors of RNA and protein synthesis.

Animals↗

Levels of placental protein 10 (PP 10) in maternal serum in normal and pathologic pregnancies.

Concentrations of placental protein 10 (PP 10) were measured by radioimmunoassay and found to be detectable but very low in nonpregnant women and in men. In an assay of 223 samples from normal pregnancies, the mean PP 10 level was 2.7 +/- 1.0 ng/ml (mean +/- SD) at 6 to 7 weeks of gestation. The level of PP 10 in maternal sera increased gradually as pregnancy progressed to a high of 40.2 +/- 19.0 ng/ml at 38 to 39 weeks, followed by a slight decrease to 28.9 +/- 15.6 ng/ml at 40 to 41 weeks. The coefficients of variation were 8.6 to 16.2% in diurnal variation and 10.3 to 34% in day-to-day variation. Relatively lower PP 10 levels were observed in maternal sera in threatened abortion with poor prognosis, toxemia of pregnancy, intrauterine fetal death and placenta previa.

Abortion, Threatened↗

Circulating levels of placental protein 5 in normal and abnormal pregnancies.

Serum concentrations of PP5 were measured by radioimmunoassay in 219 women with normal pregnancies and 163 women whose pregnancies were complicated. PP5 in serum disappeared rapidly after delivery, with a half-life of 5-10 min in the first 10 min. Serum PP5 levels were higher in uterine than in antecubital venous blood. In normal pregnancies, PP5 was detectable at 7-8 weeks of gestation; its mean concentration rose gradually to a maximum of 17.8 +/- 10.2 ng/ml at 34-35 weeks of gestation. Elevated serum PP5 concentrations were noted in patients whose pregnancies were complicated by toxemia of pregnancy with appropriate-for-date baby or by twin pregnancy. Low serum PP5 concentrations tended to be found in patients whose pregnancies were complicated by abortion, intrauterine fetal death, and hydatidiform mole. Marked abnormal PP5 levels were not found in patients with maternal diabetes and placenta previa. These findings suggest that the assay of serum PP5 concentrations can be a useful parameter in determining the prognosis of abnormal pregnancies.

Abortion, Threatened↗

Effects of calcium antagonists, especially nifedipine, on variant angina, resting angina, and unstable angina.

The effects of drugs were evaluated in 47 cases with variant angina (VA), 19 with resting angina showing ST depression (RA), and 84 with unstable angina (UA). In VA patients, calcium antagonists were effective in 87.1% of the cases, while other drugs were effective in 56.3%. The difference was statistically significant. In RA patients, calcium antagonists were effective in 80.0% of the cases and other drugs in 44.4%. Nifedipine was effective in all 5 cases with coronary stenosis of more than 75.0%. All cases of RA had multiple vessel disease and nifedipine was effective in 80.0% of the patients. Nifedipine was effective in 83.3% of VA cases showing ST elevation during an exercise test, and was particularly effective in all patients having attacks only at rest. The effects of nifedipine were confirmed in 83.3% of UA cases. These results indicate that calcium antagonists are effective in VA, RA, and UA.

Aged↗

Concentrations of SP1 and beta-hCG in serum and cerebrospinal fluid and concentrations of hCG in urine in patients with trophoblastic tumour.

Using immunological techniques urinary hCG, pregnancy-specific beta 1-glycoprotein (SP1) and beta-subunit of hCG (beta-hCG) levels were measured in the serum and cerebrospinal fluid of patients with trophoblastic tumours. After removal of hydatidiform moles, urinary hCG, beta-hCG and SP1 levels were similar, but SP1 levels tended to exceed serum beta-hCG levels. SP1 usually disappeared first. In patients with metastatic choriocarcinoma, SP1 levels appeared to be lower than beta-hCG values in serum and cerebrospinal fluid, but urinary hCG, beta-hCG and SP1 concentrations all decreased during chemotherapy. Measurements of SP1 levels may well be useful in the monitoring of patients being treated for trophoblastic tumours.

Chorionic Gonadotropin↗

A single serum dilution method for the quantitation of neutralizing antibodies to varicella-zoster virus.

A one-point serum dilution method for determination of neutralizing antibody in human sera to varicella-zoster (V-Z) virus instead of the serial serum dilution method was investigated. Focus counting was performed under a microscope on day 5 to 6 after inoculation of V-Z virus into 6-well plastic trays in which human embryonic lung cells were grown. A table was constructed to estimate the ND50 titers by the per cent reduction of the focus count from the control at only one dilution of test sera. The estimated ND50 values agreed well with those determined by the serial serum dilution method. Test sera showed a slight nonspecific reactivity at low serum dilutions, but reliable results could usually be obtained at a serum dilution of 1:8 or more. This method, which saves materials and labor, was applied to the quantification of neutralizing antibody against V-Z virus in human sera with satisfactory accuracy and reproducibility.

Adolescent↗

Radioimmunoassay of hCG as an early diagnosis of cerebral metastases in choriocarcinoma patients.

To determine the early cerebral involvement of choriocarcinoma, the following studies were employed. By comparing hCG titers in measurements of serum and cerebrospinal fluid (CSF) hCG-beta through radioimmunoassay (RIA), serum/CSF ratios of titers were calculated in patients with normal pregnancies and in those with trophoblastic neoplasia. In normal pregnancies, the mean ratio of serum/CSF hCG was more than 45.5 +/- 6.0 (mean +/- SEM):1. In neoplasia without metastases to the brain, the ratio was more than 41.0:1. However, 2 patients with cerebral choriocarcinoma showed low ratios of 23.0:1 and 20.9:1, respectively. This suggests that determination of the beta-hCG concentration ratio of serum to CSF using RIA might give a more reliable evaluation for the early detection of choriocarcinoma metastasized to the brain.

Brain Neoplasms↗

Purification and some properties of deoxyribonuclease whose synthesis is controlled by gene 49 of bacteriophage T4.

An enzyme which specifically cleaves very-fast-sedimenting DNA of bacteriophage T4 is synthesized after infection of T4, and its synthesis is controlled by gene 49 [1,2]. This enzyme has been proved to be a DNase [2]. We have purified this DNase 3000-fold from extracts of E. coli infected with T4. The purified preparation was practically free from other DNases, and the DNase activity was not detectable in cells infected with a mutant defective in gene 49. The enzyme activity from cells infected with a temperature-sensitive mutant of gene 49 was also temperature-sensitive, suggesting strongly that gene 49 is a structural gene of the DNase. The molecular weight of the wild-type enzyme was estimated to be 50 x 10(3) by gel filtration chromatography. The purified DNase did not cleave native and denatured DNAs of T3 and T4, but cleaved renatured T3 DNA with enzymatically fragmented T3 DNA, indicating that gaps in the DNA duplex are structures susceptible to the DNase. Cleavage of the hybridized T3 DNA occurred when the fragmented DNA was phosphorylated at either the 3' or 5'-strand termini.

Deoxyribonucleases↗