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Biomedical subjects

N Okamoto

Publications and source records attributed to N Okamoto.

At least 271 records · Page 15Linked to original sources
PubMed1989

[Cockayne syndrome: siblings with different ultraviolet sensitivity and early onset of manifestations].

Siblings of Cockayne syndrome were reported. Both of them had characteristic manifestation of Cockayne syndrome. A 4-year-old boy had been noted to have irritability and nystagmus from the 6th day of his life, and his elder sister, 8 years old, had been diagnosed as cerebral palsy at the age of 6 months. The elder sister lacked photosensitivity clinically. The proband was more severely affected than his elder sister on both cerebral CT-scan and electrophysiological studies. Reduced colony forming ability after ultraviolet exposure is currently considered to be the primary abnormality in Cockayne syndrome. The cells originating from the boy had moderately reduced colony forming ability after ultraviolet irradiation, whereas the cells from his elder sister showed mildly reduced colony forming ability. There may be some relationship between the severity of the symptoms and the colony forming ability. There is a broad spectrum of clinical manifestations in Cockayne syndrome. Further investigations are necessary to clarify the relationship between the cytological abnormalities of Cockayne syndrome and its neurological manifestations.

Child↗
PubMed1989

[The relative risk of a multiple primary cancer occurrence].

Patients diagnosed with cancer of the stomach, colon, breast, and uterus at Kanagawa Cancer Center have been studied for the possibility of having multiple primary cancers. The total occurrence rates of a second primary cancer were 3.2% in men and 4.0% in women. The relative risk (RR) of man with cancer of the stomach showed a significantly heightened chance of developing cancer of colon (RR, 4.2), and women with cancer of the breast for developing cancer of lung (4.2) and of the opposite breast (8.5). Further women with an endometrial cancer had a high risk for developing a cancer of ovary (30.0).

Adult↗
PubMed1988

CSE (common standards for quantitative electrocardiography) data testing in Japan.

The authors comment on the present status of computerized electro-cardiogram (ECG) works in Japan and demonstrate the preliminary tentative results of CSE (common standards for quantitative electrocardiography) data analysis using the Nagoya program. The more detailed results of the performance of several programs in CSE data analysis are discussed by Dr. Willems.

Diagnosis, Computer-Assisted↗
PubMed1988

Cerebral blood flow during ACTH therapy: especially diurnal changes within the first week of therapy.

Changes in cerebral blood flow (CBF) were evaluated in children with epilepsy treated with adrenocorticotrophic hormone (ACTH) by the Doppler ultrasound method. The average maximal blood velocity (A/L) and maximal end-diastolic blood velocity (d) of the internal carotid artery, as indices of CBF, significantly decreased during ACTH therapy. These values had already decreased at 30 minutes after the first injection of ACTH and were hardly restored 24 hours later just before the next injection. Such changes repeatedly occurred for the first four days of therapy so that the reductions in the A/L and d values proceeded in a stepwise manner. These values became minimum at around one week after initiation of the therapy and then gradually increased, returning to the original levels by the 8th week of therapy. Investigation of the changes in cerebral metabolism seemed to be the next step for elucidation of the mechanism underlying the CBF reduction during ACTH therapy.

Adrenocorticotropic Hormone↗
PubMed1988

Recovery curve of the H-reflex in normal infants, central coordination disturbance cases and cerebral palsy patients within the first year of life.

The differences in the recovery curve of the H-reflex in the gastrocnemius within the first year of life were evaluated among 81 normal controls, 40 infants with cerebral palsy and 11 infants with central coordination disturbance (CCD). In normal controls, the recoveries for the groups of under 6 months of age were more marked than those for the groups of 6 months and over of age, with interstimulus intervals of 400 msec and less. The results for the infants with cerebral palsy showed more rapid recovery and facilitation of the reflex compared to those in the normal control infants throughout the first year of life. The recovery curves for the infants with CCD were similar to those for the infants with cerebral palsy in part. It was considered that the recovery curve of the H-reflex might provide additional information for evaluating an infant's motor function.

Age Factors↗
PubMed1988

A comparative epidemiologic study on geographic distributions of cancers of the lung and the large intestine in Japan.

To examine what kinds of factors could have caused the geographic variation observed in lung cancer morbidity in Japan, a correlation study was performed comparing various regional traits. The same study was also conducted on large intestinal cancer, aiming to distinguish the possible urban factors associated with both cancers. Lung cancer was highly correlated with industrialization-related factors such as localization of manufacturing industries, automobile traffic and air pollution, whereas colon cancer was correlated with the population density of workers in the tertiary industries such as services, trade and government. A multiple regression analysis could not detect any single factor with an exceptionally strong influence on either cancer. The present findings suggest that the hazardous environmental condition of urban areas has, to some extent, contributed to the recent increase of lung cancer cases in this country.

Age Factors↗
PubMed1988

Evaluation of a new monoclonal radioimmunoassay system for carcinoembryonic antigen.

A newly established monoclonal radioimmunoassay system (kit II) for carcinoembryonic antigen (CEA) was evaluated in comparison to a conventional polyclonal system (kit I). Among 619 unselected serum samples, approximately 15% were CEA positive with kit I, whereas 27% were positive with kit II; consequently, approximately 12% showed dissociated CEA values to be positive only with kit II. More than 75% of patients with the dissociated values were found to have a malignant disease. Positive rates in normal individuals (266 samples) were less than 5% with both the kit I and kit II and, in those with benign disease were 11.9% with kit II, except for liver cirrhosis in which a quite high positive rate (58%) was obtained. In contrast, a definitely increased positive rate in malignant disease (381 samples) was obtained with kit II (61.4%) in comparison to that with kit I (42.3%). The assessment of technical qualities, such as reproducibility, recovery and dilution tests, demonstrated the excellent performance of kit II.

Adult↗
PubMed1987

Antigenic heterogeneity of carcinoembryonic antigen in the circulation defined by monoclonal antibodies against the carbohydrate moiety of carcinoembryonic antigen and closely related antigens.

Six mouse monoclonal antibodies reactive with carcinoembryonic antigen (CEA) were prepared and used for the analysis of the antigenic heterogeneity of CEA in patient sera. Their reaction specificity and the chemical nature of antigenic epitopes recognized by them were analyzed by radioimmunoassay on the basis of reactivities with different preparations of CEA, normal fecal antigen 2, and nonspecific cross-reacting antigen 2 before and after chemical and/or enzymatic treatment. Two antibodies, F3-30 and F4-82, raised with CEA were reactive with different peptide epitopes on the antigen molecules and revealed a quite universal reactivity with all CEA, normal fecal antigen 2, or nonspecific cross-reacting antigen 2 preparations tested. The serum CEA values obtained with these antibodies were highly correlated with those obtained with conventional radioimmunoassays for CEA. The other four antibodies (F4-11 and F33-37 raised with CEA, F8-52 with normal fecal antigen 2, and F48-60 with nonspecific cross-reacting antigen 2) were found to recognize carbohydrate epitopes with different specificities and revealed very heterogeneous reactivities. The serum CEA values estimated with these four antibodies were highly variable depending on the antibody used, suggesting that the expression of carbohydrate epitopes on the CEA molecules in patient sera was quite heterogeneous. The antigenic heterogeneity of the carbohydrate epitopes was detected even in a single patient serum by affinity chromatography. The causes that give rise to the difference in CEA values between the Roche and the Daiichi kits were analyzed on the basis of reactivities of three groups of patient sera, which showed extremely different ratios for the Roche and Daiichi kits, with monoclonal anti-carbohydrate antibodies. The results obtained suggest that, at least in part, the diversity of antigenic expression on carbohydrate chains on the CEA molecules in patient sera and the variation in specificity or quantity of anti-carbohydrate antibodies in the polyclonal antibody preparations used for the respective assay systems may result in the differences in the estimated CEA values.

Antibodies, Monoclonal↗
PubMed1987

Desmin distribution in the cardiac outflow tract of the chick embryo during aortico-pulmonary septation.

The appearance and distribution of desmin, a muscle type intermediate filament, was examined in the truncus arteriosus of the chick embryonic heart during AP septation by an indirect immunofluorescence method. Prior to septation, on the 4th day of incubation, staining with antidesmin antibody was observed in the AP septum anlagen in the distal truncus. No staining with the antibody was detected in the developing tunica media of the great arteries in the distal truncus at this stage. During septation, on the 5th day of incubation, intense staining with the antidesmin antibody was observed in the cell condensation of the AP septum. In the 6-day-old embryo, the staining in the AP septum was reduced, but fluorescence by staining with the antibody was observed in the developing tunica media. No fluorescence was detected in other mesenchymal cells in the truncal swellings. Because of the time of appearance and the localization of antidesmin reactivity in the developing AP septum, it is suggested that muscle-type cells exist in the AP septum, and that these cells may perform an important function in septation.

Animals↗
PubMed1987

Epitope mapping of the carcinoembryonic antigen by monoclonal antibodies and establishment of a new improved radioimmunoassay system.

A comprehensive mapping of epitopes on the carcinoembryonic antigen (CEA) molecule has been achieved by analyses of the specificities of 146 monoclonal antibodies (MAbs) from more than 300 hybridomas established recently. The reactivities of MAbs were analyzed by radioimmunoassays (RIA) with highly purified preparations of CEA and related antigens including normal fecal antigen-1 (NFA-1), NFA-2 in normal adult feces, nonspecific cross-reacting antigen (NCA) in lung and NCA-2 in meconium. The MAbs could be divided into five groups: group I, 23 clones directed to the NCA-common part of the CEA molecule; group II, 31 clones directed to the normal fecal cross-reacting antigen (NFCA)-common part; group III, 46 clones directed to the NFA-1-common part; group IV, 33 clones reactive with the heterogeneous carbohydrate part; and group V, 13 clones directed to the CEA-distinctive part which seemed to be highly specific for CEA. Mutual inhibitions of CEA binding between MAbs of the individual groups revealed that at least 25 different subgroups can be defined i.e., 4, 7, 8, 4, and 2 subgroups in groups I to V, respectively. The epitopes recognized by the group IV MAbs were found to be sensitive to oxidation with periodate, while the epitopes defined by MAbs of the other groups were resistant to this treatment. A solid-phase sandwich-type RIA system for CEA was established by using 2 MAbs from groups II and III as the CEA catcher and an MAb of group V as the tracer. This assay was shown to exhibit improved cancer-specificity and accuracy in the estimation of serum CEA levels.

Antibodies, Monoclonal↗
PubMed1987

Preventive effect of HB vaccination against liver cancer: an estimation by simulation.

In order to analyze the rapidly rising male mortality rate from liver cancer and to estimate the preventive effect of large-scale hepatitis B vaccination, we calculated the future number of deaths from liver cancer and cases of hepatitis B-related liver cancer by the linear/curved regression technique and the simulation method. Published statistics and research data were utilized for the calculation. The results of the calculation showed: 1) the increase in number of deaths from liver cancer for males would continue at the same rate as today, 2) this increase in number of deaths from liver cancer was caused by factor(s) not related to hepatitis B infection, 3) the ratio of hepatitis B virus horizontal infection to vertical infection has been sharply decreasing since the 1970s. The effect of the decrease of hepatitis B virus horizontal infection on the prevention of liver cancer is expected to be larger and to appear at an earlier stage than the effect of large-scale hepatitis B vaccination in Japan.

Age Factors↗
PubMed1987

The risk of a second primary cancer occurring in five-year survivors of an initial cancer.

Patients with a greater than five-year survival diagnosed with cancer of the stomach, colon, breast and uterus (included in situ) at the Kanagawa Cancer Center from 1963 to 1980 were studied for multiple primary cancers. They were followed up to December 31, 1985, for the occurrence of second primary cancers by means of a record linkage to the population-based cancer registry in Kanagawa Prefecture. The occurrence rate of total second primary cancers was 2.6% (76/2,977). Among the first primary cancer sites, the rate for cancer of the colon was highest: 5.3% (5/94), and the rate for women with cancer of the uterus lowest: 1.4% (16/1,146). The number of observed second primary cancers was compared with the expected number, which was calculated by the person-years method, to obtain an estimate of the risk. The relative risks (RR: observed: expected value) of women with cancer of the breast were significantly high for developing cancer of the colon (RR, 3.7), cancer of the opposite breast (RR, 3.9) and cancer of the ovary (RR, 5.8). Men with cancer of the stomach had a significant risk of developing cancer of the colon (RR, 3.3). It may be considered, at least in part, that some cancer patients, especially those with cancer of the breast, have a high risk of a second primary cancer occurring. These results may provide clues and information to the etiology of predisposition to and prevention of cancer.

Adult↗
PubMed1986

Deletion of proximal 6q: a clinical report and review of the literature.

We report on a 13-year-old boy who had an interstitial deletion of the long arm of chromosome 6[46,XY,del(6)(pter----q13::q15----qter)]. A characteristic facial appearance with facial asymmetry, vertebral anomalies, valgus heels with flat feet, and congenital heart defect seem to form part of a specific del 6q syndrome.

Abnormalities, Multiple↗
PubMed1986

Deletion 14q(q24.3 to q32.1) syndrome: significance of peculiar facial appearance in its diagnosis, and deletion mapping of Pi(alpha 1-antitrypsin).

A 10-month-old Japanese boy who had interstitial deletion of the long arm of chromosome No. 14; 46,XY, del(14)(pter----q24.3: :q32.1----qter) is reported. A peculiar facial appearance, including round face, frontal hypertrichosis with thick eyebrows, horizontal narrow palpebral fissures, a short bulbous nose with a flat nasal root, and mild micrognathia, appeared to be common with the two previously reported cases. We stress the significance of this peculiar facial appearance in the diagnosis of 14q-(q24.3 to q32.1) syndrome. The level of alpha 1-antitrypsin in the patient was only about half of that of his parents and controls, and the Pi locus was tentatively assigned to band 14q32.1.

Chromosome Banding↗