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Biomedical subjects

K Sasajima

Publications and source records attributed to K Sasajima.

At least 73 records · Page 4Linked to original sources
PubMed1984

[Reactor neutron activation analysis for aluminium in the presence of phosphorus and silicon. Contributions of 28Al activities from 31P(n, alpha) 28Al and 28Si(n, p) 28Al reactions].

Reactor neutron activation analysis for aluminium in samples containing phosphorus and silicon was studied. The experiments were performed by using neumatic tube of the Kyoto University Reactor (KUR). At first, the ratios of the 28Al activity produced from 27Al(n, gamma) 28Al reaction by thermal neutrons to that from 31P(n, alpha) 28Al reaction by fast neutrons, and to that from 28Si(n, p) 28Al reaction were measured by gamma-ray spectrometry. With a ratio of about 5 for the thermal to fast neutron flux of KUR, the ratio of the 28Al activity from aluminium to that from phosphorus was to be 812 +/- 7, and to that from silicon 282 +/- 3. Secondly, the contributions of 28Al activities from phosphorus and silicon and the determination limit of aluminium were calculated for various parameters, such as fast neutron flux, thermal to fast neutron flux ratio, amounts of phosphorus and silicon, etc. Thirdly, on the basis of these results, aluminium contents in spinal cords and brains of amyotrophic lateral sclerosis, Parkinsonism-dementia complex and control cases were determined.

Activation Analysis↗
PubMed1983

[Determination of the Ca/P atomic ratio in the spinal cord of patients with amyotrophic lateral sclerosis by neutron activation and X-ray fluorescence analysis].

Ca/P atomic ratios in spinal cords of seven amyotrophic lateral sclerosis (ALS) cases were determined by neutron activation and X-ray fluorescence analyses, and were compared with those of seven control cases. In order to obtain calibration curves, the standard samples with 0.01-0.1 of Ca/P atomic ratio were prepared by mixing diammonium hydrogen phosphate with calcium carbonate. In neutron activation analysis, gamma-ray spectra of 49Ca and beta-ray intensities of 32P produced from (n, gamma) reactions of the spinal cords and standard samples were measured by Ge(Li) and GM detectors, respectively. In X-ray fluorescence analysis, the samples were excited with 1.6 MeV alpha particle beam accelerated by a Van de Graaff accelerator, manganese K X-rays from 55Fe radioactive source and rhodium K alpha X-rays from X-ray tube, respectively. The characteristic X-ray spectra were measured by Si(Li) or proportional detector. From the peak areas on the spectra and beta-ray intensities, the Ca/P atomic ratios in spinal cords were determined. Based on these results, the Ca/P atomic ratio of precipitate including calcium and phosphorus in spinal cord of ALS case was calculated. As a result, the Ca/P atomic ratios in spinal cords of ALS and control cases were 0.018-0.021 and 0.030-0.049, respectively. The calculated Ca/P atomic ratio in the precipitate of ALS case was estimated to be 1.6.

Amyotrophic Lateral Sclerosis↗
PubMed1982

Sequential morphological studies of the esophageal carcinoma of rats induced by N-methyl-N-amylnitrosamine.

N-Methyl-N-amylnitrosamine was given to male Wistar rats in the drinking water at a concentration of 0.003% for 8 weeks. Three rats were autopsied weekly from the first to the 25th week. The stages of hyperplasia, dysplasia and squamous cell carcinoma in the esophagus were chronologically observed. Hyperplasia and dysplasia were found by the 6th week and continuously observed until the end of the experiment. Early squamous cell carcinomas were found in the 13th week. They showed endophytic or exophytic growths. Histologically, the endophytic growths were well-differentiated squamous cell carcinomas and the exophytic growths were poorly-differentiated. Advanced carcinomas were first found in the 15th week and were almost well-differentiated. Carcinomas were not found in papillomas. The incidence of carcinomas increased with time, being 9 out of 15 rats (60%) in the final 21st through 25th weeks. Lymph node metastasis was found in one rat, killed at the 24th week.

Animals↗
PubMed1981

Cytochemical localization of alkaline phosphatase in intestinal metaplasia of the human stomach.

Alkaline phosphatase in the brush border of areas of intestinal metaplasia of human stomach was studied cytochemically. All absorptive cells in the upper part of the villi of the duodenum had strong alkaline phosphatase activity but, in areas of intestinal metaplasia, the metaplastic glands consisted of alkaline phosphatase-positive and negative absorptive cells. Alkaline phosphatase activity was found in tall dense microvilli of absorptive cells in areas of intestinal metaplasia and in the duodenum. However, in some areas of metaplastic epithelium the activity was very weak in some tall dense microvilli of absorptive cells but strong in those of neighbouring absorptive cells. No alkaline phosphatase activity was found in short sparse microvilli of absorptive cells in areas of intestinal metaplasia. The difference in alkaline phosphatase activity in microvilli of different cells in areas of intestinal metaplasia, which is not seen in the duodenum, indicates abnormal morphological and enzymatic differentiation intestinal metaplasia.

Alkaline Phosphatase↗
PubMed1981

Seedling leiomyoma of the esophagus and esophagogastric junction zone.

The esophagus was totally excised for histopathological examination in 276 autopsy cases and 66 surgical cases (total, 342 cases). Leiomyoma of the esophagus was observed in 27 of the 342 cases. The tumors were present in 22 of the 225 male cases and in 5 of the 117 female cases. There were 38 leiomyomas among the 27 cases. Most of the leiomyomas originated in the inner circular muscle. None of the tumors was more than 7 mm. in length. Twenty-five of the 38 leiomyomas were located in the esophagogastric junction zone. Thus, subserial histological examination revealed leiomyomas at a higher frequency than that in previous reports.

Adolescent↗
PubMed1981

Early changes of dog esophageal mucosa induced by N-ethyl-N'-nitro-N-nitrosoguanidine.

Early changes in the esophageal mucosa of dogs induced by N-ethyl-N'-nitro-N-nitrosoguanidine (ENNG) were studied. Seven one-year-old beagle dogs were given a solution of 250 micrograms ENNG/ml to drink ad libitum for 4 months. Three different kinds of lesions (10 erosive carcinomas, 4 slightly elevated microcarcinomas and 19 leukoplakias) were recognized. These three kinds of lesions were not located adjacent to one another, and were surrounded by almost normal stratified squamous epithelium. The foci of the carcinomas revealed an abrupt transition to normal epithelium and were considered to have arisen abruptly from normal esophageal epithelium. The histogenesis of squamous cell carcinomas of the esophagus in dogs may differ from that in man.

Animals↗
PubMed1980

[Alpha particle excited X-ray fluorescence analysis for trace elements in cervical spinal cords of amyotrophic lateral sclerosis (author's transl)].

The mean contents of trace elements in anterior gray horn section of cervical spinal cords of six amyotrophic lateral sclerosis (ALS) cases were relatively determined against those of six control cases by alpha-particle excited X-ray fluorescence analysis. The anterior gray horn section of cervical spinal cord samples were excited by 1.6 MeV alpha-particle beam of 2 mm diameter accelerated with a Van de Graaff accelerator, and characteristic X-ray spectra were measured with alpha Si(Li) detector. From the peak area on the X-ray spectra, the relative mean contents of the trace elements in cervical spinal cords of ALS and control cases were determined. As a result, the X-ray peaks of Al, Si, P, S, Cl, K, Ca, Ti, V, Mn, Fe, Cu and Zn were detected. The contents of Al, Si, P, Ca, Ti, V, Mn and Fe in ALS cases were higher than those in control cases. The contents of S, Cl, K, Cu and Zn in ALS and control cases were equal to each other within standard deviation. The precipitation mechanisms of Al, Si, P, Ca, Ti, V, Mn and Fe into cervical spinal cord of ALS cases are discussed on the basis of the previous studies.

Alpha Particles↗
PubMed1979

Intestinal metaplasia and adenocarcinoma induced in the stomach of rats by N-propyl-N'-nitro-N-nitrosoguanidine.

PNNG, the propyl derivative of MNNG, was administered to Wistar rats by a concentration of 59.5 micrograms/ml in the drinking water for 4, 8, and 12 months and the rats were killed in the 15th month. Intestinal metaplasia was induced in the glandular stomachs of 25%, 75%, and 83% of the rats treated with PNNG for 4, 8, and 12 months, respectively. Metaplastic glands were found in the pyloric region, especially near the pyloric ring. These glands contained goblet cells and columnar cells with striated borders. No tumors were found in the stomach of rats after 4-months treatment, but adenomas were found after 8-months treatment, and both adenomas and adenocarcinomas after 12-months treatment.

Adenocarcinoma↗
PubMed1979

Promoting action of croton oil on gastrocarcinogenesis by N-methyl-N'-nitro-N-nitrosoguanidine in rats.

The promoting effect of croton oil on gastrocarcinogenesis by MNNG was examined in male Wistar rats. Gastric carcinomas were found in five of 10 rats given 83 micrograms/ml MNNG for three months and then 0.02% croton oil with 0.5% Tween 60 as solvent for nine months. No gastric carcinomas were found in rats given MNNG for three months and then Tween 60 only for nine months. The incidence of gastric carcinomas in these two groups was significantly different (p less than 0.05). No tumors were found in rats given only croton oil with Tween 60.

Adenocarcinoma↗
PubMed1978

Induction of intestinal metaplasia in the stomachs of rats by N-methyl-N'-nitro-N-nitrosoguanidine.

N-Methyl-N'-nitro-N-nitrosoguanidine (MNNG) was administered orally to male Wistar rats at a concentration of 83 microgram/ml in the drinking water for 2, 4, 5, and 7 months; the rats were killed at about month 15. Intestinal metaplasia was found in the stomachs of 80-100% of the rats treated with MNNG for 4 or more months, of 37.5% treated with MNNG for 2 months, and of 10% of the controls. Metaplastic glands, composed of goblet cells and columnar cells with striated borders, were found in the pyloric region. Paneth's cells were found at the bottom of metaplastic glands in a rat treated with MNNG for 4 months. The incidence of well-differentiated adenocarcinomas of the stomach was 63-90% in rats treated with MNNG for 4 or more months and 25% in those treated with MNNG for 2 months.

Adenocarcinoma↗
PubMed1977

Carcinogenicity of a food additive, AF-2, in hamsters and mice.

The carcinogenicity of a food additive, 2-(2-furyl)-3-(5-nitro-2-furyl) acrylamide (trade name, AF-2), was studied. A diet containing AF-2 at a rate of 0.25% was administered to male golden hamsters and male ddY mice. The hamsters developed squamous cell carcinomas in the forestomach after the 49th day from the start of administration. In mice fed a AF-2 diet for 308 days, squamous cell carcinoma was observed in the forestomach after the 381th day from the start of the experiment; in some cases the carcinoma metastasized to the lung and liver.

Animals↗
PubMed1977

Induction of liver tumors in rats by sodium nitrite and methylguanidine.

The carcinogenicity of sodium nitrite and methylguanidine singly and together were examined in rats. A hepatocellular carcinoma, a hemangiosarcoma and a spindle cell sarcoma were found in 3 of 15 rats fed continuously on pellet diet containing 0.16% sodium nitrite and 0.16% methylguanidine. Hemangiomas and bile duct adenomas of the liver were also found in 6 and 8, respectively, of the 15 rats in this group. Hemangiomas and bile ducts adenomas of the liver were found in 2 and 3, respectively, of the 4 rats fed on pellet diet containing 0.16% sodium nitrite. Only 1 of 5 rats fed on pellet diet containing 0.16% methylguanidine developed a hemangioma. No tumor was found in the control group. All the tumors were found in rats that survived for over 12 months. No significant changes were detected in the esophagus or stomach.

Adenoma, Bile Duct↗
PubMed1977

Esophageal and gastric cancers with metastases induced in dogs by N-ethyl-N'-nitro-N-nitrosoguanidine.

Three 6-month-old male beagle dogs were given a solution of 150 microng N-ethyl-N'-nitrosoguanidine (ENNG)/ml to drink ad libitum for 9 months. They all developed esophageal squamous cell carcinomas and gastric adenocarcinomas. The stomach adenocarcinomas were mostly in the antrum along the lesser curvature and were either well differentiated or poorly differentiated, with or without signet ring cells. The well-differentiated adenocarcinomas metastasized to the liver, and the poorly differentiated ones metastasized to the lymph nodes. The gastric mucosa in the antrum was atrophic, and the muscularis mucosae was fibrotic. Esophageal lesions were multicentric moderately differentiated squamous cell carcinomas, and they developed without diffuse hyperplastic changes of the epithelium. One dog with a large ulcerated carcinoma of the esophagus had metastases in the lung, liver, peritoneum, and abdominal lymph nodes. One dog also had a hemangiosarcoma with hepatic metastasis and spindle cell sarcoma in the stomach and duodenum, respectively.

Adenocarcinoma↗