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Biomedical subjects

I Ikeda

Publications and source records attributed to I Ikeda.

At least 73 records · Page 4Linked to original sources

Exogenous hypercholesterolemic rats, compared with their progenitor, Sprague-Dawley rats, promptly alter cholesterol metabolism in the liver and secrete cholesterol-rich particles in response to dietary cholesterol.

Early responses of cholesterol metabolism to dietary cholesterol were compared between exogenous hypercholesterolemic (ExHC) and Sprague-Dawley rats. Both strains had a similar radioactivity of [14C]cholesterol in the serum half a day after the oral administration, but thereafter the radioactivity disappeared slowly in ExHC rats. ExHC rats promptly altered in response to the dietary cholesterol, activities of cholesterol 7 alpha-hydroxylase and cholesterol synthesis in the liver and fecal excretion of bile acids derived from [14C]cholesterol administered orally. Lymphatic transport for 24 hr [14C]cholesterol was similar between the strains. Triton administration resulted in a marked accumulation of cholesterol in serum d > 1.006 g/mL lipoproteins in ExHC rats; in addition, the formation of cholesteryl esters from [14C]oleic acid intravenously infused was greater in ExHC rats. These results indicate that ExHC rats increase serum cholesterol in response to exogenous cholesterol by decreasing the liver uptake and enhancing the secretion in the liver.

Animals↗

Pyridinium cross-links as urinary markers of bone metastases in patients with prostate cancer.

OBJECTIVES: To determine whether the urinary excretion of urinary pyridinoline (Py) and deoxypyridinoline (dPy) serve as markers to evaluate the activity of bone metastases and the response to endocrine therapy, by determining the relationship between the excretion of these compounds and the activity of bone metastases in patients with prostate cancer. PATIENTS AND METHODS: Urine specimens were obtained from 15 patients with benign prostatic hypertrophy (BPH), 17 with carcinoma clinically confined to the prostate and 26 with prostate cancer and bone metastases. Among the patients with prostate cancer and bone metastases, 15 were new or reactivated cases and the 11 others were well controlled by hormonal therapy. Urinary Py and dPy were analysed using high-pressure liquid chromatography. RESULTS: Patient with new or reactivated prostate cancer with bone metastases had a higher urinary excretion of Py and dPy than did the patients with BPH, patients with prostate cancer and no bone metastases and patients with prostate cancer and bone metastases well controlled with hormonal therapy. Urinary levels of these compounds correlated with the extent of bone metastases in new and reactivated cases. Initial high levels of these cross-linked compounds in patients with multiple bone metastases fell as the prostate cancer was controlled by hormonal therapy. CONCLUSION: Urinary excretion of Py and Dpy appears to be a useful marker for evaluating the activity of bone metastases and their response to hormonal treatment in prostate cancer.

Aged↗

Metabolic interactions between essential and trans-fatty acids.

Trans-fatty acids exacerbate essential fatty acid deficiency in experimental animals by interfering with the metabolism of linoleic (18:2n-6) and alpha-linolenic (18:3n-3) acids and, hence, the eicosanoid production. The interfering effect depends on the type of trans-fatty acid. The detrimental effect of trans-fatty acid, however, apparently disappears when dietary linoleic acid is sufficiently supplemented. Trans-fatty acids appear to disturb fetal growth and birth weight, possibly by the same mechanism.

Animals↗

Lymphatic absorption of seal and fish oils and their effect on lipid metabolism and eicosanoid production in rats.

Eicosapentaenoic (EPA) and docosahexaenoic acids (DHA) were distributed mainly in the sn-1 and 3 positions of seal oil triglyceride and in the sn-2 position of fish oil triglyceride. In Expt. 1, the structural distribution of EPA and DHA in lymph triglyceride of rats given seal or fish oils was similar to the distribution in the administered oils. In Expt. 2, seal oil-rich or fish oil-rich fats having constant polyunsaturated/monounsaturated/saturated fatty acids and n-6/n-3 polyunsaturated fatty acids ratios were fed to rats for 3 weeks. Seal oil more effectively reduced plasma and liver triglyceride than fish oil. Ratio of the productions of aortic prostacyclin and platelet thromboxane A2 stimulated by thrombin was significantly higher in rats fed seal oil than in those fed fish oil. The results suggested that the different intramolecular distribution of EPA and DHA in dietary fat affected lipid metabolism differently in rats.

Absorption↗

Effects of dietary fats and curcumin on IgE-mediated degranulation of intestinal mast cells in brown Norway rats.

Brown Norway rats were primed intraperitoneally with beta-lactoglobulin for 3 wk to induce reaginic antibody, during which time they were fed diets containing 10% each of coconut oil (CO), high oleic safflower oil, safflower oil (SO), or fish oil, then they were challenged for 3 h orally with the antigen. The dietary SO, compared to other dietary fats, resulted in lower circulatory release of rat chymaseII (RChyII), an indicator of degranulation of mucosal mast cells in the intestine, in response to the antigen. Addition of 0.5% curcumin to the CO or SO diet lowered the release. The SO diet, compared to CO diet, tended to increase the concentration of reaginic antibody, but the influence of curcumin addition was not prominent. These results indicate that dietary ingredients differently influence the synthesis of immunoglobulin E and degranulation of mast cells.

Animals↗

Effect of dietary linoleic, alpha-linolenic and arachidonic acids on lipid metabolism, tissue fatty acid composition and eicosanoid production in rats.

Rats were fed semipurified diets containing 10% fat with a constant polyunsaturated/monounsaturated/saturated fatty acid ratio of 1:1:1. This was performed by mixing vegetable oils. Linoleic acid was the sole polyunsaturated fatty acid in the linoleic acid group. The alpha-linolenic and arachidonic acids were contained at the 1% level in the diet at the expense of linoleic acid in the alpha-linolenic acid and arachidonic acid groups, respectively. The concentration of serum triglyceride, phospholipid and liver triglyceride were significantly lower in the alpha-linolenic acid and arachidonic acid groups than in the linoleic acid group. Hepatic phospholipids were significantly higher in the alpha-linolenic acid and arachidonic acid group as compared to the linoleic acid group. Compared to the linoleic acid group, the percentages of arachidonic acid in the phosphatidylcholine (PC) and phosphatidylethanolamine (PE) in the liver and heart were significantly lower in the alpha-linolenic acid group; in contrast, they were significantly higher in the arachidonic acid group. Dietary arachidonic acid, but not alpha-linolenic acid, resulted in a marked reduction of linoleic acid and increased arachidonic and n-6 docosapentaenoic acids in heart cardiolipin. Platelet thromboxane (TX) A2 production tended to be lower in the alpha-linolenic acid group as compared to the linoleic acid and arachidonic acid groups. There was no difference in TXA2 production between the linoleic acid and arachidonic acid groups. The aortic production of prostacyclin (PGI2) was the same among the three groups. The ratios of TXA2 and PGI2 in the linoleic acid and arachidonic acid groups were comparable, whereas they were significantly higher than that in the alpha-linolenic acid group. The results demonstrate that dietary arachidonic acid enriches the arachidonic acid content in tissue phospholipids more effectively than linoleic acid, whereas the effect on the production of TXA2 and PGI2 was comparable under these experimental conditions.

Animals↗

Prognostic significance of Ki-67 labeling index in urothelial tumors of the renal pelvis and ureter.

PURPOSE: We evaluated the prognostic significance of the Ki-67 labeling index in 70 patients with primary urothelial tumors of the renal pelvis and ureter. MATERIALS AND METHODS: Immunohistochemical staining for Ki-67 in archival tumor materials was done by the streptavidin-biotin method. RESULTS: Univariate survival analysis showed that the prognosis of patients with a high Ki-67 labeling index of 21.7 or more was significantly worse than that of patients with an intermediate labeling index of 13.3 to less than 21.7 (p < 0.01) or a low labeling index of less than 13.3 (p < 0.001). Multivariate survival analysis showed that staining for Ki-67 labeling index was significantly correlated with prognosis (p < 0.01). CONCLUSIONS: Analysis of Ki-67 labeling index provides useful prognostic information about patients with primary urothelial tumors of the renal pelvis and ureter.

Antigens, Neoplasm↗

Loss of heterozygosity at the p53, RB, DCC and APC tumor suppressor gene loci in human bladder cancer.

PURPOSE: Allelic losses within several tumor suppressor genes have been detected frequently in various types of human cancer. We investigated the roles and possible interactions of the tumor suppressor genes p53, Rb, DCC and APC in bladder cancer. MATERIALS AND METHODS: Loss of heterozygosity (LOH) of these 4 genes was examined in 45 human bladder cancers by polymerase chain reaction and restriction fragment length polymorphism assay. RESULTS: Of the evaluated cases, LOH was seen at P53 in 38%, at Rb in 22%, at DCC in 36% and at APC in 6% of tumors. Loss of heterozygosity at p53 and Rb was predominantly observed in high grade (grade 3) and/or invasive (T2 or greater) tumors, whereas LOH at DCC was present irrespective of tumor grade and stage. Allelic losses at either p53, Rb, DCC or APC were seen in 82% of high grade tumors, but in only 21% of low grade (grade 1 and 2) tumors (p<0.005). Similarly, 71% of invasive tumors had LOH at one or more loci compared with 20% of superficial (Ta and T1) tumors (p<0.005). Interestingly, p53-LOH and Rb-LOH were often observed simultaneously in the same tumor. CONCLUSIONS: These results suggest that loss of the p53, Rb and/or DCC genes is involved in most of the late and some of the early steps of bladder carcinogenesis.

Base Sequence↗

Metastatic choriocarcinoma of the kidney discovered by refractory hematuria.

A case of metastatic choriocarcinoma of the kidney is reported. A 34-year-old married woman was referred to our department complaining of gross hematuria, fever and loin pain. Computed tomography revealed a right renal tumor with mixed density and multiple lung metastases. We performed nephrectomy to control refractory hematuria. The histological diagnosis of the tumor was metastatic choriocarcinoma. In young women, with gross hematuria, menstrual irregularity and atypical renal tumor with multiple lung metastases, metastatic choriocarcinoma of the kidney should be suspected.

Adult↗

[Combination therapy with 5-fluorouracil (5-FU), cisplatin (CDDP) and interferon alpha-2B (IFN alpha-2B) for advanced renal cell carcinoma].

Eleven patients with metastatic renal cell carcinoma received combination therapy with 5-fluorouracil (5-FU), Cisplatin (CDDP) and Interferon alpha-2b (IFN alpha-2b). For 5 days, 500 mg of 5-FU was administered by continuous intravenous infusion daily; 20 mg/m2 CDDP was injected intravenously daily for 5 days, and 3 or 6 million units of IFN alpha-2b was administered intramuscularly twice a week for 3 weeks. This treatment cycle was repeated every 3 weeks. One of 11 patients achieved a partial response, and the response rate was 9%. High grade toxicities (WHO grade 3 or 4), nausea and vomiting (27%), leukocytopenia (9%), anemia (9%) and thrombocytopenia (18%) were seen. One of the reasons that this regimen dose not appear to be effective may be the low total dose of 5-FU for renal cell carcinoma.

Aged↗

Lymphatic transport of alpha-, gamma- and delta-tocotrienols and alpha-tocopherol in rats.

Lymphatic transport of alpha-, gamma- and delta-tocotrienols and alpha-tocopherol was measured in thoracic duct-cannulated rats. Animals were administered 3 ml of a test emulsion containing 200 mg sodium taurocholate, 50 mg fatty acid free-albumin, 200 mg fat and 100 mg of a mixture of tocotrienols and alpha-tocopherol (Exp. 1) or 10 mg of purified alpha-, gamma- or delta-tocotrienol or alpha-tocopherol (Exp. 2) through a gastric tube. Quantitative lymphatic recovery of oleic acid given as triolein was obtained in these experimental conditions. The 24-hours recovery of tocotrienols and alpha-tocopherol were 10-20% of the administered dose in Exp. 1. The recovery of alpha-tocotrienol was about 2-times higher than that of alpha-tocopherol, while that of gamma- and delta-tocotrienols was intermediate between these two alpha-forms. In Exp. 2, where these compounds were administered individually, the 24 hours recovery ranged from 22 to 37% of the administered dose. Again, the recovery of alpha-tocotrienol was significantly higher than that of the other tocotrienols and alpha-tocopherol, while that of gamma- and delta-tocotrienols and alpha-tocopherol was comparable. Thus, the results show the preferential absorption of alpha-tocotrienol compared to gamma- and delta-tocotrienols and alpha-tocopherol.

Animals↗

Digestion and lymphatic transport of eicosapentaenoic and docosahexaenoic acids given in the form of triacylglycerol, free acid and ethyl ester in rats.

Lymphatic transport of eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids given as trieicosapentaenoyl glycerol (TriEPA) and tridocosahexaenoyl glycerol (TriDHA) was compared with that of ethyl ester and free acid in rats cannulated with thoracic duct. Trioleoylglycerol (TO) served as a control. EPA and DHA, compared with oleic acid, were slowly transported in lymph irrespective of fat types administered. Total 24-h recovery of DHA in all fat types and ethyl EPA was significantly lower compared to that of oleic acid. Lymphatic recovery of EPA and DHA in rats given TriEPA and TriDHA was significantly higher at the first 3 h after the administration compared to those given as free acid or ethyl ester. The recovery in rats given free acid at a later stage (9-24 h) was higher than that of the other fat types. As a result, the 24-h recovery was comparable between triacylglycerol (TAG) and free acid, while it was significantly lower in ethyl ester. Although TriEPA and TriDHA were slowly hydrolyzed by pancreatic lipase in vitro compared with TO and TAGs rich in EPA or DHA at the second position, the hydrolysis rate at 60 min incubation was comparable among the TAGs examined. The hydrolysis rate of ethyl esters was extremely low even in 6 h incubation with lipase. These observations show that presence of EPA and DHA at the 1- and 3-positions of TAGs does not result in their lower recovery in lymph. Processes after lipolysis may be responsible for their low recovery in lymph. In a separate study, slower lymphatic recovery of DHA given as free acid than TriDHA was improved by the simultaneous administration of TO, but not by free oleic acid. The observations suggest that the slow recovery of free acid is caused by delayed TAG synthesis in mucosal cells and/or low micellar solubility of fatty acids in the intestinal lumen due to a limited supply of 2-monoacylglycerol (MAG). A large portion of EPA and DHA were recovered in lymph chylomicrons and very low density lipoproteins (VLDL, > 95%) and incorporated into TAG (84-92%) fraction in all fat types examined. Lymphatic recovery rate of simultaneously administered cholesterol was influenced by the fat types given.

Animals↗

Effects of randomization of partially hydrogenated corn oil on fatty acid and cholesterol absorption, and tissue lipid levels in rats.

Randomization of partially hydrogenated corn oil containing approximately 45% of trans octadecenoic acid only slightly, but not significantly, increased the lymphatic fatty acid absorption in rats. No effect of randomization was observed on cholesterol absorption. When rats were fed these fats at the 8.8% level (with 1.2% safflower oil) for three weeks, the concentrations of serum cholesterol, and serum and liver phospholipid were significantly higher in randomized fat than in control fat, which was composed of 9% high-oleic safflower oil and 1% palm oil. Liver cholesterol tended to be higher in randomized fat. In contrast, nonrandomized fat was not hyperlipidemic compared to control fat. Although the fatty acid composition of liver phospholipids suggested a possible interference of trans fatty acid with the metabolism of linoleic acid to arachidonic acid, there was no effect of randomization. In the two hydrogenated fat groups, trans octadecenoic acid was incorporated and distributed similarly in adipose tissue triacylglycerol. These observations indicated that randomization of partially hydrogenated fat is not beneficial to various lipid parameters in rats.

Absorption↗

Inhibitory effect of ethanolamine plasmalogen on iron- and copper-dependent lipid peroxidation.

The effect of ethanolamine plasmalogen (EtnPm) on lipid peroxidation was investigated in liposomal suspension of egg yolk phosphatidylcholine. EtnPm inhibited iron- and copper-dependent peroxidation in the presence of preformed hydroperoxides, although it was not effective for radical initiator mediated lipid peroxidation. EtnPm resulted in complete binding of iron to liposomal lipids, suggesting that EtnPm exerts its inhibitory effect on lipid peroxidation through inhibiting preformed peroxide decomposition by trapping transition metal ions.

Antioxidants↗

Differential effects of geometrical isomers of octadecadienoic acids on ketogenesis and lipid secretion in the livers from rats fed a cholesterol-enriched diet.

The effect of cis,cis (cc)- and trans,trans (tt)-9,12-octadecadienoic (18:2) acids on ketogenesis and lipid secretion was compared in isolated perfused livers from cholesterol-fed rats. The hepatic uptake of 18:2 acids was comparable in both isomers. The livers perfused with cc-18:2 acid in comparison with those perfused without fatty acid substrate produced approximately 4-fold more ketone bodies accompanying the rise of the beta-hydroxybutyrate:acetoacetate ratio, while the tt-acid isomer further increased these parameters. The hepatic secretion rates of triglyceride and phospholipid as well as cholesterol were all elevated on perfusing the cc-18:2 acid as compared to without fatty acid. In contrast, the rates observed with the tt-18:2 acid isomer except for phospholipid were intermediate, indicating a reciprocal response in ketogenesis and lipid secretion by the trans isomer. The rate of incorporation of trans-fatty acid into perfusate triglyceride and cholesterol ester were lower than cis-acid, but vice versa into perfusate phospholipids. On the other hand, the effects of trans-fatty acid on the concentration and composition of hepatic lipids were less clear. These results emphasize the differential effect of geometrical isomers of the 18:2 acids on oxidation and esterification even in the livers containing a high level of cholesterol.

3-Hydroxybutyric Acid↗

Multiple malignant melanoma and squamous-cell carcinoma in a burn scar.

Malignant melanoma arising in a burn scar is very rare. Only 12 cases have been reported until now. We report a case of multiple malignant melanoma and squamous-cell carcinoma arising in the same burn scar. Reported cases of malignant melanoma arising in burn scars are also reviewed. Results of immunohistochemical studies and HLA typing of our patient and a review of previous cases suggest the aggressive behavior of malignant melanoma in burn scars.

Burns↗

[Comparisons of histological grading between biopsy and radical prostatectomy specimens in prostatic adenocarcinoma].

PURPOSE: To examine how accurately biopsy specimens reflect the corresponding excised specimens in terms of histologic grades of prostatic adenocarcinoma, histologic grades of biopsy specimens were compared to those of radical prostatectomy specimen in 29 patients who underwent radical prostatectomy without any prior treatment. METHODS: For the assessment of histological grading, Japanese General Rule for Prostatic Cancer (JGRPC), in which adenocarcinoma was graded as being either well, moderately or poorly differentiated, and Gleason's system were applied. RESULTS: According to JGRPC, histologic grades of biopsy specimens were identical to those of the prostatectomy specimens in 83% of cases, with biopsy specimens given higher grades than those of the prostatectomy specimen in 4 (14%), and lower grades in 1 (3%). According to Gleason score histological grade of biopsy specimens were identical to those of the prostatectomy specimens in only 52%. However, the grouping category of Gleason score (2 to 5, 6, 7 and 8 to 10) assigned to the biopsy was lower than that of prostatectomy specimen in only 3 cases (10%) and was greater than that of prostatectomy specimen in 5 cases (17%). CONCLUSION: These results suggest that histological grades based upon biopsy specimens will predict those of the corresponding prostatectomy specimens in the majority (72% to 83%) but not all of the cases.

Adenocarcinoma↗