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Biomedical subjects

R Chiba

Publications and source records attributed to R Chiba.

At least 73 records · Page 4Linked to original sources
PubMed1983

[Application of PIXE (particle-induced x-ray emission) method to the cytolytic test of tumor cells].

Immunological studies have often been based on the results of cytolytic assay in which cells labelled with radioactive 51Cr are usually employed. The replacement of the radioactive isotope by a stable one is obviously desirable in order to eliminate the problem of radiation hazard and to prevent environmental contamination. We applied PIXE (particle induced X-ray emission) method for the detection of stable chromium (Cr). MM46 cells labelled with natural Cr were treated with anti-MM46 serum and a rabbit complement. The remaining Cr was filtered. The released Cr was precipitated with ethanol and deposited on the filter. The specimens were bombarded with proton beams from a Van de Graaff accelerator and the X-rays produced were detected with a Si(Li) detector. The Cr peaks appeared clearly. One of the main advantages of the application of the PIXE method is its high sensitivity. Another merit of the present method is that it can easily compare the remaining ratio of several elements in cellular materials after lytic treatment. This information may be used as a parameter indicating differences in the process of cytolysis.

Animals↗
PubMed1983

[Pathological changes associated with topical chemotherapy of adriamycin for bladder cancer].

Since the study of intravesical instillation of thio-TEPA by Jones and Swinney, the method of topical chemotherapy with several anti-cancer drugs for superficial bladder tumors have been reported and it is now an established method of anti-bladder cancer treatment. Adriamycin is one of the most common topical agents against bladder tumor today. We studied the histopathological changes associated with the topical treatment in 26 cases of bladder cancer, all in which either TUR-Bt or cystectomy (partial or radical) had been performed after intravesical instillation of adriamycin. Transurethral biopsies of bladder tumor were done before the chemotherapy, and these findings were histopathologically compared with those of the surgical specimens. In 3 of the 26 cases, the tumors disappeared completely. In the other 23 cases, the main changes were: 1) cellular atrophy of tumor, 2) exfoliation, 3) interstitial hyalinous degeneration, 4) hemorrhage, and 5) dystrophic calcification. These changes are nonspecific of adriamycin, which seems to act as a toxic substance despite its potential activity to inhibit RNA replication.

Carcinoma, Transitional Cell↗
PubMed1982

Astrovirus-associated epidemic gastroenteritis in Japan.

An outbreak of epidemic gastroenteritis associated with astrovirus, the first case reported in Japan, is described. Not only children (5-6 years of age), but also staff members of a kindergarten were affected. the virus particles detected in stools were 28-30 nm in diameter with a circular outline and had the characteristic star-like configuration which allowed identification as astrovirus. Significant immune responses to the virus were confirmed by immune electron microscopy. Out of 84 children, 43 (54.2%) were affected; the common symptoms were vomiting, abdominal pain, diarrhea, and fever. All the patients recovered completely within 48 hours. Occurrence of gastroenteritis due to contact with these patients was observed in 14 of 43 families.

Antibodies, Viral↗
PubMed1982

[Arterial infusion of microencapsulated mitomycin C for the treatment of locally recurrent carcinoma of the pelvic cavity].

Ethylcellulose microcapsules of mitomycin C (MMC) were prepared. The potential therapeutic effects of intra-arterial infusion of the microencapsulated anti-cancer drugs were considered to be a function of microembolization and prolonged the drug action, that is, chemoembolization. A total of 19 patients with locally recurrent carcinoma of the pelvic cavity was subjected to transcatheter arterial chemoembolization with microencapsulated MMC. These included 7 bladder carcinomas, 7 prostatic carcinomas, 2 ureter carcinomas, 1 rectal carcinomas, 1 ovarian carcinoma and 1 cervical carcinoma. Thirteen patients had several distant or lymph node metastases. The single dose of MMC ranged from 10 to 40 mg and the total dose in each patient varied from 10 to 90 mg (mean 35 mg). The therapeutic response was evaluated by Karnofsky's criteria in terms of subjective and objective changes. Of 18 patients, 11 patients were assessed to category of I-A, B or C and 9 patients were survived over one years. Hematological toxicity occurred in 4 (22%) of 18 patients, but no treatment was needed for 3 of 4 patients. Local pain and high fever lasted more than one week were experienced in one patient. Skin necrosis lasting for a few months occurred in 10 (56%) of 18 patients. Surgical ligation of the gluteal arteries considerably prevented this painful condition. In conclusion, our clinical experiences indicate that chemoembolization is effective as a preoperative and palliative measure in the treatment of locally recurrent carcinoma of the pelvis and also helpful to control intractable symptoms such as hemorrhage or pain in patients with several metastases.

Aged↗
PubMed1981

Zinc and copper concentrations in human milk and in serum from exclusively-breast-fed infants during the first 3 months of life.

Zinc and copper concentrations in human milk and in serum from exclusively-breast-fed infants born at full-term were serially determined during the first 3 months of life by the atomic absorption spectrophotometric method. Zinc and copper concentrations of human milk decreased as the stage of lactation progressed. The mean value of the concentration of serum zinc at birth was just below the value previously reported for school children, significantly decreased at one month of age (p less than 0.02), then returned to the level at birth at 2 months of age, and reached at 3 months of age to the level of school children. On the other hand, the mean value of serum copper at birth was markedly low, and rapidly increased until 2 months of age and then gradually increased until 3 months of age. These changes in serum zinc and copper concentrations during early infancy suggested that human milk can provide sufficient zinc and copper for full-term infants during the first 3 months of life. Calculated daily zinc and copper intakes in infants fed on human milk were lower than recommended values. It is necessary to reconsider the appropriateness of previously recommended values for breast-fed animals.

Adult↗
PubMed1975

Micro-determination of bromine in biological samples using proton-induced x-ray emission spectroscopy.

The plasma level of bromine was measured by a proton-induced X-ray emission spectroscopy. Since bromine is the most difficult halogen to be determined and appears only in trace quantities, powerful techniques are required. The excellent reproducibility was obtained on 19 measurements on a sample of a single individual; the coefficient of variation was 6.3%. The average and standard deviation of plasma bromine levels on 47 young women were 0.50 and 0.10 mg/100 ml, respectively. Results by other methods in the literature were briefly reviewed.

Animals↗