The effects of radiation therapy on the tissue capsule of soft tissue implants.

A prosthesis has been developed for cosmesis after lumpectomy surgery for breast carcinoma. The device is saline filled and percutaneously adjustable in volume to permit an optimal cosmetic result after surgical wound healing. A series of 24 studies of 18 weeks' duration using the adult rabbit animal model were first used to study tissue capsule formation around textured versus smooth surface control implants and to evaluate the effects of volume adjustments on the tissue capsule. Single or multiple adjustments of implant volume had no effect on tissue capsule thickness or morphology. Because lumpectomy surgery is invariably followed by radiation therapy, a series of six studies was then conducted to determine the effects of a typical course of radiation therapy on tissue capsule formation. One week after device implantation, a 4 x 4 cm field including the implant was irradiated with 5,000 rad (200 rad/day x 5 days/week x 5 weeks). The animals were maintained for a 6 week period after radiation treatment. After sacrifice, the implants were removed, and the tissue capsules studied using conventional histologic techniques, including scanning and transmission electron microscopy. There was no statistically significant difference in tissue capsule thickness compared to nonirradiated controls. Tissue capsule morphology, however, differed markedly. Radiation therapy decreased angiogenesis, cellularity, and the inflammatory cell response to the implants. Qualitatively, radiation treatment seemingly improved rather than compromised the connective tissue response to the implants.

[Concentration profile of PCBs in the digestive tract of rat fed with cholestyramine and rice bran fiber diet].

The aim of this study is to examine the inhibitory effect of rice bran fiber (RBF) and cholestyramine for intestinal absorption of polychlorinated biphenyls (PCBs). Sixteen rats were orally given at the dose of 100 mg of PCBs per kg of the animal, and were divided into four groups (A-D): Rats in each group were housed with the normal diet for the first 7 days, and subsequently, were given with the same diet as control for group A, with the diet containing 10% RBF for group B, with the diet containing 5% cholestyramine for group C and with the combined diet containing 10% RBF and 5% cholestyramine for group D for the next 10 days. All rats were sacrificed on the 17th day after PCBs administration, and PCBs in contents of the digestive tracts were determined: small and large intestine resected was divided into two parts each of the same length, and the contents were chemically analyzed to determine PCBs. PCBs concentration in rats of group A decreased in order of upper portions (1.0 microgram/g) and then lower (0.6 microgram/g) of small intestine, and upper (0.5 microgram/g) and then lower (0.4 microgram/g) of large intestine. Decreasing the PCBs concentration might be due to re-absorption in the intestine. In the case of groups B-D, PCBs concentration was in order of upper and then lower of small intestine, and large intestine. It was indicated that PCBs re-absorption in intestine is inhibited by the intake of RBF, cholestyramine, and RBF and cholestyramine.

[Polychlorinated dibenzofurans (PCDFs) in the subcutaneous adipose tissue of yusho patients and normal controls].

Polychlorinated dibenzofurans (PCDFs) are well known to be the toxic chemicals in both animal experiments and human studies. It is, therefore, important to determine the level of PCDFs still retained in patients for understanding relationship between the concentration of PCDFs and present symptoms of the disease. In this study, the abdominal subcutaneous adipose tissue of 18 yusho patients and those of 11 normal controls who were all of volunteers were collected, and their levels were determined by high resolution gas chromatography/high resolution mass spectrometry. Results obtained were as follows: The principal compounds detected in the adipose tissue of yusho patients were 2,3,4,7,8-pentachlorodibenzofuran (PenCDF), 1,2,3,4,7,8- and 1,2,3,6,7,8-hexachlorodibenzofuran (HCDF). The concentration of the compounds in 7 patients, wearing typical symptoms, from 160 to 3,000 ppt for 2,3,4,7,8-PenCDF, from 51 to 1,000 ppt for 1,2,3,4,7,8-HCDF, and from 16 to 220 ppt for 1,2,3,6,7,8-HCDF. In normal controls, 2,3,4,7,8-PenCDF was detected only in five samples at the low level of from 16 to 38 ppt. On an average, PCDF levels in in the typical 7 yusho patients and 11 normal controls were 1,900 ppt and 16 ppt, respectively. On the basis of the results, the concentrations of PCDF congeners in the adipose tissues of the typical 7 patients was 100 times higher than that of the normal controls. Hence, we consider that the present levels of PCDFs in the patients probably play an important role for the symptoms of the yusho.

[Concentration of PCDDs, PCDFs and coplanar PCBs in breast milk of Yusho patients and normal subjects].

Levels of PCDDs, PCDFs and coplanar PCBs were measured in human breast milk obtained from two Yusho patients and nine healthy subjects. The concentrations of PCDDs, PCDFs and coplanar PCBs in the breast milk of respective Yusho patients were 18.2 and 28.9, 168.8 and 418.3, and 23.8 and 55.1 pg Toxic Equivalents (TEQs)/g fat, respectively, and their mean concentrations in normal controls were 8.2, 5.1 and 21.8 pg TEQ/g fat, respectively. The results also indicated that there was a significant difference between Yusho patients and normal subjects in the concentrations of certain isomers of PCDDs, PCDFs and coplanar PCBs in the breast milk. For example, the levels of 1, 2, 3, 6, 7, 8-HxCDD were 4 and 8 times higher than the mean concentration in the normal subjects, and 2, 3, 4, 7, 8-PeCDF, 1, 2, 3, 4, 7, 8-HxCDF and 1, 2, 3, 6, 7, 8-HxCDF, so-called 'Yusho isomers' were 15 to 98 times higher than those in the normal subjects. Daily intakes of TEQ values were estimated to be 506 and 2200 pg TEQs/kg/day for breast-feeding babies of Yusho patients, and to be from 97 to 197 pg TEQs/kg/day for healthy subjects. These TEQ values were much greater than the ADI of 1-10 pg/kg/day, therefore, we should give due attention to the possible health effects due to PCDDs, PCDFs and coplanar PCBs in the breast milk of healthy mothers, as well as Yusho mothers.

[Therapeutic trial for promotion of fecal excretion of PCDFs and PCBs by the administration of cholestyramine in Yusho patients].

Any effective therapy for elimination of causal agents remaining in Yusho patients was not found until now. To know the profile of fecal excretion of polychlorinated dibenzofurans (PCDFs) and polychlorinated biphenyls (PCBs), the amounts of PCDFs and PCBs in the stool of six Yusho patients with the typical symptoms were determined. The stool samples of Yusho patients were collected in 1989. PCDFs, i.e., 2,3,7,8-tetrachlorodibenzofuran (TCDF), 2,3,4,7,8-pentachlorodibenzofuran (PnCDF), 1,2,3,4,7,8- and 1,2,3,6,7,8-hexachlorodibenzofurans (HxCDFs), 1,2,3,4,6,7,8-heptachlorodibenzofuran (HpCDF) and octachlorodibenzofuran (OCDF) were detected in all of the samples. PCDFs found in the stool samples were mostly PnCDF and HxCDFs. Of PCDFs detected, PnCDF and HxCDFs contributed to 42 +/- 4.7% and 43 +/- 5.5% as mean +/- SE, respectively. The fecal excretion of PnCDF and HxCDFs in Yusho patients was 720 +/- 490 pg/day and 790 +/- 620 pg/day as mean +/- SE, respectively. On the other hand, the fecal excretion of PnCDF and HxCDFs in normal controls was 32 +/- 13 pg/day and 47 +/- 5.2 pg/day as mean +/- SE, respectively. The fecal excretion of PnCDF and HxCDFs in Yusho patients was about 23 times and 17 times each higher than that in normal controls. The fecal excretion of PCBs in Yusho patients and normal controls was 400 +/- 430 ng/day and 150 +/- 39 ng/day, respectively, as mean +/- SE. In order to promote the excretion of these toxic chemicals in the stool of Yusho patients, the patients were continuously administered with cholestyramine, an anion exchange resin, at a dose of 4 g, 3 times a day, for 6 months.(ABSTRACT TRUNCATED AT 250 WORDS)