Search PubMed⌕ Search

Biomedical subjects

M Fukushima

Publications and source records attributed to M Fukushima.

At least 163 records · Page 9Linked to original sources

Cytotoxic mechanism of 1-(3-C-ethynyl-beta-D-ribo-pentofuranosyl)cytosine (ECyd).

The molecular mechanism of cell death induced by 1-(3-C-ethynyl-beta-D-ribo-pentofuranosyl)cytosine (ECyd: Figure 1), a potent inhibitor of RNA synthesis, was performed using mouse mammary tumor FM3A cells and human fibrosarcoma HT1080 cells. ECyd induced the characteristics of apoptosis on these cells, such as morphological changes, DNA fragmentations (Figure 2), and caspase-3-like protease activation. General caspases inhibitor (Z-Asp-CH2-DCB) inhibited these changes and cell death. We also found that ECyd induced DNA and 28S ribosomal RNA (rRNA) fragmentations. Though the mechanisms of rRNA fragmentations haven't revealed, it suggests that translational function of the treated cells should be disturbed. These results indicate that antitumor mechanism of ECyd are characteristics of apoptosis on the cells and rRNA fragmentations is one of the death events resulted inhibition of RNA synthesis.

Animals↗

Expression of thymidylate synthase in human non-small cell lung cancer.

5-Fluorouracil (5-FU) has been used worldwide, and the correlation between its effects and thymidylate synthase (TS) expression has been reported in gastrointestinal malignancy. But the significance of TS expression for 5-FU-based chemotherapy has rarely been reported in non-small cell lung cancer (NSCLC). We investigated surgically resected specimens of 23 consecutive patients with previously untreated NSCLC. We used immunohistochemistry and western blot analysis with anti-TS polyclonal antibody to evaluate the existence of TS, and fluorodeoxyuridine-5'-monophosphate (FdUMP) binding assay to evaluate the enzymic activity of TS. We found that 14 samples (60.9%) were positive immunohistochemically, and that the results of immunohistochemistry closely reflected the enzymic activity measured by FdUMP binding assay (ranging from 1.8 to 56.9 pmol/g protein). These results seem to support our experience that 5-FU and its derivatives are clinically significantly effective as a postoperative adjuvant chemotherapy against NSCLC.

Adult↗

Studies of the active substances in herbs used for hair treatment. II. Isolation of hair regrowth substances, acetosyringone and polyporusterone A and B, from Polyporus umbellatus Fries.

Fractionation of the 50% ethanol extract of Polyporus umbellatus Fries by column chromatography on Amberlite XAD-2, silica gel, Sephadex LH-20 and octadecyl silica gel (ODS) (C18)) monitored by a hair-regrowth activity assay, afforded three active principles, 1, 2 and 3. The structures of 1, 2 and 3 were determined as acetosyringone, polyporusterone A, and polyporusterone B by comparison of their spectral data with that of authentic samples, respectively. The effects of several compounds related to acetosyringone, 3,4-dihydroxybenzaldehyde or polyporusterone A on hair regrowth were also investigated.

Animals↗

Studies of the active substances in herbs used for hair treatment. III. Isolation of hair-regrowth substances from Polygara senega var. latifolia TORR. et GRAY.

Four active principles, 1, 2, 3 and 4, were isolated from Polygara senega var. latifolia TORR. et GRAY by a combination of partition and column chromatography on silica gel and octadecyl silica gel (ODS), monitored by a hair-regrowth activity assay. Compounds 1, 2, 3 and 4 were identified as senegose A, senegin II, senegin III, and senegasaponin b by comparison of their spectral data with those of authentic samples.

Animals↗

A mixture of organisms affects cholesterol metabolism together with rat cecal flora.

The effects of a mixture of organisms on cecal fermentation and cholesterol metabolism in sham-operated and cecectomized rats were investigated. Male F344 rats, allocated into four groups: cecectomized rats fed a mixture of organisms (CEMO), cecectomized rats fed rice bran (CERB), sham-operated rats fed a mixture of organisms (SHMO), and sham-operated rats fed rice bran (SHRB) for 4 weeks. The diets had 0.5% cholesterol and 0.125% sodium cholate added. There were no significant differences in the body weight gain and food intake among the groups. The cecal pH in the SHMO group was significantly lower than that in the other groups. The total cholesterol and (VLDL + IDL + LDL)-cholesterol concentrations in serum were significantly lower in the SHMO group than that in the SHRB group, and the triacylglycerol concentration in the sham-operated rats tended to decrease compared to the cecectomized rats. The fecal cholesterol excretion in the CERB group was higher than that in the other groups, and that in the SHMO group was significantly higher than in the SHRB group. The acetic acid, propionic acid, n-butyric acid, and total short-chain fatty acid concentrations in the cecum contents were significantly higher in the SHMO group than those in the other groups. Streptococcus, Bifidobacterium, and Lactobacillus in the SHMO group tended to be higher than the other groups and Bacteroidaceae in the CEMO and CERB groups were significantly higher than that in the SHMO group. The results demonstrate that the mixture of organisms was fermented with the cecal contents and that the metabolites such as short-chain fatty acid lowered the serum total cholesterol and liver cholesterol concentrations in the rats fed a cholesterol-containing diet.

Animals↗

Effects of a probiotic on the lipid metabolism of cocks fed on a cholesterol-enriched diet.

The effects of a probiotic (a mixture of Bacillus, Lactobacillus, Streptococcus, Clostridium, Saccharomyces and Candida) on the lipid metabolism, and caecal flora and metabolites of cocks were studied. The cholesterol level of the liver and serum was significantly decreased in the cocks fed on the cholesterol-enriched diet containing the probiotic. The distribution and frequency of occurrence of flora, and the chemical characteristics of the metabolites in the caecal content of the cocks were also affected by the inclusion of the probiotic in the basal and cholesterol-enriched diets. The Enterobacteriaceae species were significantly decreased in number, while the Bacillus, Streptococcus, Bifidobacterium and Lactobacillus species were significantly increased. The presence of yeast was observed, and the ammonia level was significantly reduced. The pH value, however, was not affected. The concentration of short-chain fatty acids in the caecal content of the cocks fed on the cholesterol-enriched diet supplemented with the probiotic was increased. It is, therefore, suggested that the incorporation of a probiotic in the diet would improve the balance of the intestinal flora and metabolites. Furthermore, it would also suppress the serum and liver cholesterol levels of cocks fed on the cholesterol-enriched diet.

Animals↗

Comparative hypocholesterolemic effects of five animal oils in cholesterol-fed rats.

The hypocholesterolemic efficacy of various animal oils was compared in rats given a cholesterol-enriched diet. After acclimatization for one week, male F344 DuCrj rats (8 weeks of age) that had been fed with a conventional diet were assigned to diets containing 5% of oil from emu (Dromaius), Japanese Sika deer (Cervus nippon yesoensis, Heude), sardine, beef tallow, or lard with 0.5% cholesterol for 6 weeks. After this feeding period, the concentrations of serum total cholesterol and of very-low-density lipoprotein + intermediate-density lipoprotein + low-density lipoprotein-cholesterol in the sardine oil group were significantly lower than those in the other groups. The serum high-density lipoprotein-cholesterol concentration in the Japanese Sika deer oil group was significantly higher than that in the other groups. The atherosclerotic index and liver cholesterol concentration in the sardine oil and Japanese Sika deer oil groups were significantly lower than those in the other groups. The fecal cholesterol excretion by the Japanese Sika deer oil group was significantly higher than that of the other groups, except for the sardine oil group, and the fecal bile acid excretion by the sardine oil group was significantly higher than that of the other groups, except for the lard group. These results suggest that Japanese Sika deer oil reduced the atherosclerotic index and liver cholesterol concentration in the presence of excess cholesterol in the diet as well as sardine oil did by increasing the excretion of cholesterol from the intestines of rats.

Animals↗

A prospective multicenter trial evaluating diagnostic validity of multivariate analysis and individual serum marker in differential diagnosis of pancreatic cancer from benign pancreatic diseases.

CONCLUSION: A multivariate analysis of CAMPAS-PX2 can increase its diagnostic accuracy in differential diagnosis of pancreatic cancer from benign pancreatic or extrapancreatic disease, when compared with CA19-9 alone. However, the improvement in diagnostic accuracy is still not satisfactory in spite of an elaborate combination of serum markers in diagnosis for pancreatic cancer. Optimal combination of a sensitive serum marker and another diagnostic modality, such as ultrasonography, can be a practical way to improve important diagnostic and cost-effectiveness in diagnosis for pancreatic cancer. BACKGROUND: No specific biological test has yet been developed for diagnosis of pancreatic cancer, although increasing numbers of tumor markers become available. For improvement in the diagnostic and cost effectiveness, it is important to select optimal combination of several serum markers relatively independent of each other. METHODS: A new model of discriminant function, computer-aided multivariate and pattern analysis system for pancreatic cancer examination 2 (CAMPAS-PX2), was developed based on the data of the 23 serum tumor markers from the first prospective trial (1) to differentiate between pancreatic cancer and benign pancreatobiliary disease by logistic regression analysis using a stepwise selection method. In 243 patients suspected of having pancreatic pancreatic cancer by a multicenter prospective study, the diagnostic value of the multivariate analysis, CAMPAS-PX2, was compared with the 23 markers. RESULTS: Pancreatic cancer was subsequently identified in 27 patients. Positive in disease, negative in health, and area under receiver operating characteristic curve were significantly higher by CAMPAS-PX2 (89, 87, 91%) than by CA 19-9 (78, 82, 84%), the most sensitive marker among the 23 markers.

Biomarkers, Tumor↗

Dihydropyrimidine dehydrogenase activity and messenger RNA level may be related to the antitumor effect of 5-fluorouracil on human tumor xenografts in nude mice.

We investigated the correlation between tumor sensitivity to 5-fluorouracil (5-FU) and the enzymatic activity and mRNA levels of thymidylate synthetase (TS) and dihydropyrimidine dehydrogenase (DPD) using human tumor xenografts in nude mice. Three gastric carcinoma xenografts (SC-1-NU, St-4, and H-111), two colon carcinoma xenografts (Co-4 and Col-3-JCK), one pancreatic carcinoma xenograft (PAN-3-JCK), and one breast carcinoma xenograft (MX-1) were inoculated into nude mice. When the resultant tumors reached 100-300 mg, 5-FU was administered i.p. at a dose of 60 mg/kg in a schedule of three times every 4 days, and the antitumor activity of 5-FU was evaluated as the relative mean tumor weight in treated mice compared to control mice. Xenografts were also inoculated into untreated nude mice. When tumors weighed 200-300 mg, tumor tissues were resected for measurement of tumoral TS and DPD. TS and DPD activities were detected by the TS-binding assay and a radioenzymatic assay, respectively. mRNA levels were measured by semiquantitative reverse transcription-PCR, with glyceraldehyde-3-phosphate dehydrogenase coamplified as an internal standard. TS and DPD activities ranged from 84.7 to 775.5 fmol/mg protein and from not detectable to 79.7 pmol/min/mg protein, respectively. TS and DPD mRNA levels ranged from 0.51 to 9.90 and from not detectable to 0.93, respectively. The enzymatic activities of TS and DPD were correlated with observed mRNA levels. DPD levels were significantly correlated with 5-FU sensitivity, with high DPD activity and high DPD mRNA level resulting in low sensitivity to 5-FU. In contrast, no correlation between TS level and 5-FU sensitivity was observed. Tumoral DPD activity and DPD mRNA level may be useful indicators in predicting the antitumor activity of 5-FU.

Animals↗

Relationship between intratumoral dihydropyrimidine dehydrogenase activity and gene expression in human colorectal cancer.

Dihydropyrimidine dehydrogenase (DPD) is the rate-limiting enzyme for 5-fluorouracil catabolism. In this study, both the enzymatic activity and mRNA level of DPD were estimated in the tumor tissue and adjacent normal mucosa of 51 patients with colorectal cancer. Although no significant difference in enzymatic activity was observed between tumor tissue and normal mucosa (70.4 and 70.7 pmol/min/mg protein, respectively), the mRNA level in normal mucosa was significantly higher than that in tumor tissue (1.37 and 0.39, respectively; P<0.01). A linear relationship was noted between DPD activity and the DPD mRNA level in cancerous tissue (r(s) = 0.714, P<0.001). Thus, the DPD mRNA level as determined by reverse transcription-PCR can be used to indicate the DPD activity of colorectal cancers.

Colorectal Neoplasms↗

[Anti-metastatic and anti-angiogenic activity of UFT in a lung spontaneous metastasis model in mice].

We investigated the effect of UFT on a pulmonary metastasis after excision of the primary lesion, which was induced by implantation of murine renal carcinoma cells, RENCA. The cells were implanted into the left kidney of Balb/cA mice, and nephrectomy of the left kidney with a primary tumor was performed on day 10 after implantation. Administration of antitumor drugs, was started on day 13 [UFT (20 mg/kg, p.o., 5'-DFUR (24.6 mg/kg, p.o.), 5-FU (19 mg/kg, i.v.), TNP-470 (30 mg/kg, s.c.)]. In this metastasis model, the estimated mean survival time of the control group was 41.3 +/- 2.9 days. A significant life-prolonging effect was observed for UFT and 5-FU (T/C: 160.8%, 125.7%, respectively). An inhibitory effect on the growth of metastatic tumors in the lung was detected for both UFT and TNP-470 (TWI: 55.5%, 48.7%, respectively), but not 5'-DFUR. In a dorsal air sac (DAS) model, UFT abrogated angiogenesis induced by RENCA in a dose-dependent manner. These data suggest that the life-prolonging effect of UFT results from the continuous exposure of a tumor to its cytotoxic effects and anti-angiogenic activity.

Animals↗

[Effects of propofol infusion on respiration, systemic circulation and regional organ blood flow].

Using a nonradioactive colored microsphere (CMS) method, we measured the regional organ blood flow in rats before, during and after constant flow infusion of propofol (PF). Eighty-seven male Sprague-Dawley rats weighing 408 +/- 12 g (mean +/- SD) were used for the experiment. Spontaneous respiration was maintained throughout the course of the experiment. The infusion of PF was started from the right femoral vein at a constant rate of 5 mg.kg-1.h-1 for the first 30 minutes. CMSs of three different colors were injected through the catheter placed between the left ventricle and the right common carotid artery before, during, and 15 min after PF infusion, respectively. At the end of the experiment, the animals were sacrificed, and the quantity of CMSs trapped in the heart, liver, gastrointestinal (G-I) tract, spleen, and kidneys was measured by the matrix inversion technique. Neither pulse rate nor arterial blood pressure declined significantly during or after the PF infusion. No significant change was observed in arterial blood gas analysis (pH, PaCO2, PaO2, HCO3-, and base excess), as a monitor of respiration of the animals, during or after PF anesthesia. Nor did cardiac output change significantly. Regional organ blood flow, i.e., blood flow in the right and left ventricles, hepatic arterial blood flow, portal venous blood flow, and renal blood flow all remained constant during and after the PF anesthesia. In conclusion, during PF anesthesia at the rate of 5 mg.kg-1.h-1 both systemic circulation and regional organ blood flows were maintained within normal range without any respiratory depression, indicating that PF can be useful for intravenous sedation of outpatients.

Anesthetics, Intravenous↗

[Actual situations and problems of patients receiving home IVH--trial use of an assessment chart for outpatients].

In order to improve the quality of life (QOL) and continue nursing, we used an assessment chart to investigate the actual situations and problems of the patients receiving home intravenous hyperalimentation (IVH). From January, 1997 to June, 1999, we investigated 20 patients with home IVH. To 7 patients among them, we asked questions using Kurihara's assessment chart for QOL, plus our original questions concerning IVH. The mean age of the patients was 61 years old, and 19 of them had advanced cancers. Forty percent of the patients maintained the IVH all by themselves and 10% of the patients needed the support of their family. The remaining 50% of the patients left all to their family. There were 9 incidents of trouble during the maintenance of the IVH. Almost all patients from whom informed consent had been received were satisfied with the home IVH. On the contrary, all patients who had not given informed consent were not satisfied with the home IVH. According to the results of the assessment chart, even if the total points were low, the points for the IVH were high in the patients had given informed consent. The main reason for lower QOL was pain. The points for the families were lower than those for the patients. They sometimes complained of uneasiness and dissatisfaction with the support they received. We conclude that therapies to improve symptoms and mental state are necessary to satisfy the patients, and that it is important to support not only the patients but also their families.

Adult↗

Nucleosides and nucleotides. 175. Structural requirements of the sugar moiety for the antitumor activities of new nucleoside antimetabolites, 1-(3-C-ethynyl-beta-D-ribo-pentofuranosyl)cytosine and -uracil1.

We previously designed 1-(3-C-ethynyl-beta-d-ribo-pentofuranosyl)uracil (EUrd) and its cytosine congener (ECyd) as potential multifunctional antitumor nucleoside antimetabolites. They showed potent and broad-spectrum antitumor activity against various human and mouse tumor cells in vitro and in vivo. To clarify the structure-activity relationship of the sugar moiety, various 3'-C-carbon-substituted analogues, such as 1-propynyl, 1-butynyl, ethenyl, ethyl, and cyclopropyl derivatives, of ECyd and EUrd were synthesized. We also prepared 3'-deoxy analogues and 3'-homologues of ECyd and EUrd with different configurations to determine the role of the 3'-hydroxyl group and the length between the 3'-carbon atom and the ethynyl group and a 2'-ethynyl derivative of ECyd to determine the spatial requirements of the ethynyl group. The in vitro tumor cell growth inhibitory activities of these nucleosides against mouse leukemic L1210 and human KB cells showed that ECyd and EUrd were the most potent inhibitors in the series, with IC50 values of 0.016 and 0.13 microM for L1210 cells and 0.028 and 0.029 microM for KB cells, respectively. Only 3'-C-1-propynyl and -ethenyl derivatives of ECyd showed greatly reduced cytotoxicity. We found that the cytotoxic activity of these nucleosides predominantly depended on their first phosphorylation by uridine/cytidine kinase.

Animals↗