Reappraisal of classification of distal cholangiocarcinoma based on tumour depth

Background

In the eighth edition of the AJCC cancer staging classification, the T system for distal cholangiocarcinoma (DCC) has been revised from a layer-based to a depth-based approach. The aim of this study was to propose an optimal T classification using a measured depth in resectable DCC.

Methods

Patients who underwent pancreatoduodenectomy for DCC at 32 hospitals between 2001 and 2010 were included. The distance between the level of the naive bile duct and the deepest cancer cells was measured as depth of invasion (DOI). Invasive cancer foci were measured as invasive tumour thickness (ITT). Log rank χ2 scores were used to determine the cut-off points, and concordance index (C-index) to assess the survival discrimination of each T system.

Results

Among 404 patients, DOI was measurable in 182 (45·0 per cent) and ITT was measurable in all patients, with median values of 2·3 and 5·6 mm respectively. ITT showed a positive correlation with DOI (rs = 0·854, P < 0·001), and the cut-off points for prognosis were 1, 5 and 10 mm. Median survival time was shorter with increased ITT: 12·4 years for ITT below 1 mm, 5·2 years for ITT at least 1 mm but less than 5 mm, 3·0 years for ITT at least 5 mm but less than 10 mm, and 1·5 years for ITT 10 mm or more (P < 0·001). This classification exhibited more favourable prognostic discrimination than the T systems of the seventh and eighth editions of the AJCC (C-index 0·646, 0·622 and 0·624 respectively).

Conclusion

ITT is an accurate approach for depth assessment in DCC. The four-tier ITT classification with cut-off points of 1, 5 and 10 mm seems to be a better T system than those in the seventh and eighth editions of the AJCC classification.

Serum factors that suppress cytotoxic effect of methotrexate

AIM

To study the phenomenon that human erythroid leukemia K-562 cells are more sensitive to cytotoxic effect of antimetabolites when cultured in a serum-free medium than in a conventional medium containing fetal calf serum (FCS).

METHODS

Cytotoxic effects of methotrexate, azaserine and 5-fluorouracil were estimated by accessing the lactate dehydrogenase (LDH) activity of viable tumor cells. Proteins of FCS were separated using two-dimensional electrophoresis followed by mass spectrometry analysis.

RESULTS

Addition of 10% FCS attenuated anti-tumor activity of methotrexate and azaserine against K-562 cells compared with serum-free medium. Such an activity of FCS was different for each serum lot. Comparison of the proteins in active serum lot with those in not active one using two-dimensional electrophoresis showed that in the active serum there were proteins 150 kDa, which were absent in the not active serum lot. Mass spectrometry indicated that all those proteins had the amino acid sequence of albumin. Sera of one healthy volunteer and two patients with thyroid cancer also attenuated the activity of the agent.

CONCLUSION

Several lots of FCS and human serum demonstrated the ability to attenuate the cytotoxic effect of methotrexate in vitro, possibly due to the formation of albumin dimers/MTX complexes.

In vivo anti-tumor activities of gelatin

AIM

As reported previously, porcine skin gelatin exerted direct anti-tumor effect in vitro and induced anti-tumor peritoneal macrophages in vitro. The present study investigated whether or not the gelatin exerted anti-tumor effect in vivo.

METHODS

In vitro anti-tumor activities of peritoneal macrophages and the gelatin were evaluated with tritium thymidine uptake by target tumor cells. In vivo anti-tumor activity was evaluated with the survival of tumor-bearing animals and the size of the tumor.

RESULTS

Intraperitoneal daily administration of 12.5 mg of the gelatin prolonged the survival of mice which had been intraperitoneally inoculated with MH134 (hepatic cell carcinoma cell line) or Colon 26 (colon carcinoma cell line) tumor cells, and there were no tumors in case of MH134 cells inoculation. Intraperitoneal daily administration of 12.5 mg of the gelatin did not affect growth of subcutaneous MH134 tumor. The gelatin administered subcutaneously did not affect the survival of mice with intraperitoneal MH134 tumor. On the other hand, bovine skin gelatin administered subcutaneously achieved statistically significant prolongation of the survival. The contact of MH134 cells with porcine skin gelatin for 5 min was required for the gelatin to exert its anti-tumor activity in vitro. Porcine skin gelatin of 12.5 mg injected intraperitoneally was detected as protein in the peritoneal cavity 5 min after the injection. Peritoneal macrophages elicited by intraperitoneal injection with porcine skin gelatin suppressed tritium thymidine uptake by MH134 cells more strongly than those elicited by thioglycollate injection.

CONCLUSION

Porcine skin gelatin administered intraperitoneally prolonged the survival of tumor-bearing mice via activation of peritoneal macrophages and involvement of direct anti-tumor activity of porcine skin gelatin. Key Words: porcine skin, gelatin, dissemination.

Fluvastatin depresses the enhanced lipid peroxidation in vitamin E-deficient hamsters

Fluvastatin, a 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitor, has recently been reported to have the antioxidative activity in vitro. However, it is still unclear whether chronic treatment with this drug actually leads to amelioration of the redox status in the body. In this study, we investigated the antioxidative effect of fluvastatin in vivo, using a vitamin E-deficient hamster model, an in vivo model of enhanced oxidative stress. After pre-treatment with a vitamin E-deficient diet for 2 months, fluvastatin, pravastatin or probucol was added to the diet for 1 month. Vitamin E deficiency caused a significant increase in the levels of plasma oxidative stress markers such as 8-iso-prostaglandin F2alpha (8-iso-PGF2alpha) and hydroperoxides. Furthermore, there was a significant increase in the oxidizability of plasma lipids in the vitamin E-deficient animals, indicating that the oxidative stress was increased in the circulation. Fluvastatin markedly depressed the above oxidative stress markers in plasma, and significantly decreased the oxidizability of plasma lipids without affecting their levels. Probucol, a reference antioxidant, also showed a similar effect while pravastatin, another HMG-CoA reductase inhibitor, showed only a weak improvement. We suggest that the treatment with fluvastatin leads to a reduction of oxidative stress in vivo, which is mainly derived from its antioxidative property rather than its lipid-lowering activity.

Effects of fluvastatin and its major metabolites on low-density lipoprotein oxidation and cholesterol esterification in macrophages

We investigated effects of fluvastatin, a 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitor, and its major metabolites, M2 and M4, on CuSO4-induced low-density lipoprotein (LDL) oxidation and cholesteryl ester accumulation in mouse peritoneal macrophages. All the test compounds inhibited LDL oxidation, and M2 had the most potent effect comparable to vitamin E. When LDL was previously incubated with the test compounds in the presence of CuSO4, the pre-treatment resulted in a marked reduction of facilitated cholesteryl ester accumulation in macrophages. Supplementation of mevalonate did not overcome the inhibitory effects of fluvastatin and its metabolites on both LDL oxidation and facilitated cholesterol esterification. Pravastatin, another HMG-CoA reductase inhibitor, did not show any inhibitory effect. Consequently, these effects of fluvastatin and its metabolites are considered to be derived from their own unique chemical structures. Moreover, fluvastatin and M2 directly inhibited cholesterol esterification induced by oxidized LDL in macrophages, but pravastatin was also found to have a weak effect. As their inhibitory effects were overcome by addition of mevalonate, the direct inhibitory effect on cholesterol esterification would be a common property of HMG-CoA reductase inhibitors. The inhibitory effects of fluvastatin and its metabolites on both LDL oxidation and cholesterol esterification in macrophages may contribute to the antiatherogenic action in vivo.

The effectiveness of administering a minimal dose of octreotide long-term prior to surgery for insulinoma: report of a case

We report herein the case of an 80-year-old woman with insulinoma who was regarded as an unsuitable candidate for immediate surgery due to her advanced age and obesity, for whom octreotide, a long-acting analogue of somatostatin, was used to improve her hypoglycemia and hyperinsulinemia without hyperalimentation. Administering a minimal dose of octreotide for a long period resulted in the improvement of leg edema, weight control, and cardiopulmonary function, and resection of the pancreatic tumor was safely carried out without any complications.

Fluvastatin normalizes the decreased turnovers of glutathione and ascorbic acid in Watanabe heritable hyperlipidaemic rabbits

1. Fluvastatin, a 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitor, has been reported to decrease the oxidizability of plasma lipids in hyperlipidaemic subjects. In order to elucidate one of the mechanisms of this in vivo, we investigated the effects of fluvastatin and pravastatin on the decreased turnovers of reduced glutathione (GSH) and ascorbic acid (AA) in Watanabe heritable hyperlipidaemic (WHHL) rabbits. 2. These drugs (30 mg/kg per day) equally decreased plasma levels of lipids after a 4 week treatment period. However, only fluvastatin significantly decreased thiobarbituric acid-reactive substances, which were increased in the plasma of WHHL. 3. Although these drugs did not affect the steady state levels of total glutathione and low molecular weight thiols in the liver and kidney, fluvastatin markedly normalized the rate of GSH turnover in these tissues, as determined by using L-buthionine-(S,R)-sulphoximine, a specific inhibitor of GSH synthesis. 4. Fluvastatin also increased the clearance of AA from the circulation in WHHL. 5. These results suggest that, in addition to its hypolipidaemic action, fluvastatin has the potential to improve the turnover of anti-oxidants, which is closely related to the amelioration of the redox status in the body.

Decreased turnovers of glutathione and ascorbic acid in watanabe heritable hyperlipidemic rabbits

Oxidative stress has been postulated to play important roles in the pathogenesis of various diseases such as atherosclerosis in hyperlipidemic subjects. Although the possible role of oxidation of low-density lipoprotein (LDL) in the etiology of atherosclerosis has been studied extensively, the turnover of endogenous antioxidants, which is an important protection system against oxidative stress, remains to be elucidated. The aim of our study was to determine the change of the turnover of endogenous antioxidants such as glutathione and ascorbic acid in case of hyperlipidemia, using Japanese white rabbits (JW) and Watanabe heritable hyperlipidemic rabbits (WHHL). The levels of total glutathione and low molecular weight thiols in the liver, kidney, and other organs in both strains of rabbits were similar. However, a kinetic analysis using L-buthionine-(S,R)-sulfoximine revealed that the rate of glutathione turnover in the liver and kidney of WHHL was about 50%) lower than that of JW. Furthermore, intravenously administered ascorbic acid disappeared more slowly in WHHL than in JW. These results indicate that the turnovers of both glutathione and ascorbic acid in WHHL are depressed in comparison with that in JW. These changes would be closely related to the increased oxidizability of lipids in the circulation of hyperlipidemic subjects.

Inhibitory effects of fluvastatin and its metabolites on hydrogen peroxide-induced oxidative destruction of hemin and low-density lipoprotein

Some 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors, which are used as hypolipidemic drugs, have been reported to have the potential to reduce the oxidizability of plasma low-density lipoprotein (LDL) when they are administered in vivo. Their in vivo mechanism is believed to be closely related to their hypolipidemic action based on the HMG-CoA reductase inhibitory activity. We hypothesized that some type of HMG-CoA reductase inhibitor has additional mechanism inhibiting LDL oxidation in vivo due not to its hypolipidemic action but to its direct antioxidative effect based on its unique chemical structure. We directly compared in vitro the antioxidative effects of well-known HMG-CoA reductase inhibitors (fluvastatin, pravastatin, simvastatin, cerivastatin and atorvastatin) on the hydrogen peroxide-induced oxidative destruction of hemin and LDL. Fluvastatin but not the others showed the inhibitory effect on this system. Its effect was dose-dependent and almost as strong as the natural antioxidants, alpha-tocopherol and ascorbic acid. Further, M2, which is a hydroxylated metabolite of fluvastatin, showed stronger antioxidative activity than did fluvastatin. We suggest that among these HMG-CoA reductase inhibitors, fluvastatin especially has an ability to retard the LDL oxidation which is based on not only its hypolipidemic action but also its direct antioxidative effect.

Bone metabolic analysis in patients with primary hyperparathyroidism

Surgical treatment for primary hyperparathyroidism (PHPT) improves not only the calcium and phosphate metabolism but also the bone metabolism. This study was conducted to analyze the bone metabolism after PHPT operations. Bone mineral density (BMD) was measured by dual-photon absorptiometry in 50 patients before and after operation. Osteocalcin (OC) and alkaline-phosphatase activity (Alp) in serum were measured before and after surgery as markers of bone formation, and urinary deoxypiridinorine (DPD) as an index of osteoclast activity. The 50 patients under study were 40 women (80%) and ten men (20%). Increases in BMD at the lumbar spine were remarkable at three months following operation. Slow but steady progress was made until six months, reaching a plateau thereafter. The increase in BMD of lumbar spine was approximately 10%. Urinary DPD was the most sensitive among the three bone metabolic markers. Although serum Alp and OC remained high after operation, urinary DPD was normalized earlier. The discrepancy of bone formation and resorption was shown after operation and this contributed to the increases in BMD in the first six months.

Significant change in the structure of a ribozyme upon introduction of a phosphorothioate linkage at P9: NMR reveals a conformational fluctuation in the core region of a hammerhead ribozyme

A modified hammerhead ribozyme (R32S) with a phosphorothioate linkage between G(8) and A(9), a site that is considered to play a crucial role in catalysis, was examined by high-resolution 1H and (31)P nuclear magnetic resonance (NMR) spectroscopy. Signals due to imino protons that corresponded to stems were observed, but the anticipated signals due to imino protons adjacent to the phosphorothioate linkage were not detected and the (31)P signal due to the phosphorothioate linkage was also absent irrespective of the presence or absence of the substrate. (31)P NMR is known to reflect backbone mobility, and thus the absence of signals indicated that the introduction of sulfur at P9 had increased the mobility of the backbone near the phosphorothioate linkage. The addition of metal ions did not regenerate the signals that had disappeared, a result that implied that the structure of the core region of the hammerhead ribozyme had fluctuated even in the presence of metal ions. Furthermore, kinetic analysis suggested that most of the R32S-substrate complexes generated in the absence of Mg(2+) ions were still in an inactive form and that Mg(2+) ions induced a further conformational change that converted such complexes to an activated state. Finally, according to available NMR studies, signals due to the imino protons of the central core region that includes the P9 metal binding site were broadened or not observed, suggesting that this catalytically important region might be intrinsically flexible. Our present analysis revealed a significant change in the structure of the ribozyme upon the introduction of the single phosphorothioate linkage at P9 that is in general considered to be a conservative modification.

A discussion of anti-Aspergillus niger glucose oxidase monoclonal antibody reactivity to red blood cells of several species

We observed that mouse spleen cells from rosettes with autologous red blood cells (RBCs) and that rosette-formation was suppressed by anti-Aspergillus niger glucose oxidase monoclonal antibody (mAb). In the present study, we investigated whether RBCs of species besides mice have the structure recognized by anti-A. niger glucose oxidase mAb by using rosette-formation and complement-mediated hemolysis. Lysates of monkey and human RBCs did not suppress rosette-formation whereas autologous (mouse), rat and sheep RBC lysates partially suppressed rosette-formation. Those lysates exerted their suppressive activity after they had been treated at 56 degrees C for 30 min. A. niger glucose oxidase also suppressed rosette-formation with or without treatment at 56 degrees C for 30 min. Alternatively, anti-A. niger glucose oxidase mAb lysed mouse, rat and sheep RBCs but not human RBCs with complement. These findings suggest that the cell surfaces of mouse, rat and sheep RBCs have a structure which can be recognized by anti-A. niger glucose oxidase mAb while the cell surfaces of monkey and human RBCs do not.

Protective effect of TA-993, a novel therapeutic agent for peripheral circulatory insufficiency, on skeletal muscle fatigue in a rat model of hindlimb ischemia

TA-993 (cis-(-)-2-(4-methylphenyl)-3-acetoxy-2,3-dihydro-5-(2-dimethylaminoethy l)-8-methyl1,5-benzothiazepine-4(5H)-one maleate), a new 1,5-benzothiazepine derivative, has a selective increasing action on limb blood flow in addition to an antiplatelet action. In this report we studied the effect of TA-993 on a time dependent decrease in developed tension of electrically-induced contraction of tibialis anterior muscle in a rat model of peripheral circulatory insufficiency induced by occlusion of abdominal aorta. In our preparation, the developed tension decreased by 20-30% in a sham-operated group and 30-40% in an abdominal aorta-occluded group at the end of the experimental period of 60 min. Intraduodenal administration (i.d.) of TA-993 (10 mg/kg) to the abdominal aorta-occluded rats ameliorated the decrease in developed tension to the level of the sham-operated group. Moreover, TA-993 at 10 mg/kg, i.d. significantly increased femoral arterial blood flow supplied through collateral circulation and decreased the whole blood viscosity in this model. These results suggest that TA-993 improves dysfunction of skeletal muscle contraction due to peripheral circulating insufficiency through an increase in collateral blood flow and an improvement of red blood cell deformability.

Fluvastatin, an HMG-CoA reductase inhibitor, protects LDL from oxidative modification in hypercholesterolemic rabbits

The antioxidative effect of fluvastatin sodium (fluvastatin) on low-density lipoprotein (LDL) was evaluated in vivo and in vitro. Since ex vivo measurement of the LDL oxidizability is reported to reflect the response of the atherosclerotic process, LDL isolated from rabbits fed a high cholesterol diet for 4 weeks with or without fluvastatin, pravastatin or alpha-tocopherol administration was oxidized by copper ions to estimate conjugated diene formation. Fluvastatin but not pravastatin significantly prolonged the lag time of LDL oxidized by copper ions ex vivo without affecting plasma cholesterol levels at a dose of 3 mg/kg after four weeks of treatment. Alpha-tocopherol-treated rabbits showed dramatically elongated LDL oxidation lag time at a dose of 150 mg/kg. In order to assess the mechanism, the content of alpha-tocopherol, a major endogenous antioxidant in LDL was measured, and we found that only LDL isolated from alpha-tocopherol-treated rabbits contained a significantly larger amount of alpha-tocopherol than that from high cholesterol control rabbits. To elucidate the mechanism further, the effect of fluvastatin on conjugated diene formation during copper-induced LDL oxidation in vitro was studied. Fluvastatin not only prolonged lag time, but also suppressed the rate of LDL oxidation, both in a dose dependent manner above 1 microM, while pravastatin showed no effect. These results suggest the direct antioxidative effect of fluvastatin on LDL oxidation in vivo. Since oxidation of LDL is an important step in the initiation and progression of atherosclerosis, fluvastatin may reduce the risk of this condition not only by lowering plasma cholesterol but also by protecting LDL from oxidation.

Antioxidative property of T-0970, a new ureidophenol derivative

We investigated the antioxidative property of T-0970, a newly synthesized ureidophenol derivative. The inhibitory effect of T-0970 on spontaneous lipid peroxidation in rat brain was 10 times greater than those of well-known antioxidants such as butylhydroxytoluene (BHT), probucol and alpha-tocopherol. T-0970 also showed dose-dependent free radical scavenging activities in vitro for both superoxide anions and hydroxyl radicals. The radical-scavenging potencies of T-0970 were about 10-30 times stronger than those of BHT. We evaluated the in vivo antioxidative ability of T-0970 in the animal model of acute oxidative tissue injury in rats. Intraperitoneal injection of ferric nitrilotriacetate (Fe/NTA) caused an acute and remarkable increase in the level of thiobarbituric acid-reactive substances (TBARS) in both plasma and the liver, and also resulted in a considerable elevation of the plasma levels of GOT and GPT indicative of hepatic injury. Both oral and intravenous administration of T-0970 dose-dependently depressed these diagnostic parameters. These results indicate that T-0970 may have a therapeutic potential in various diseases associated with oxidative tissue injury.

Superoxide anion scavenging properties of fluvastatin and its metabolites

We investigated the in vitro superoxide anion scavenging activities of fluvastatin and its metabolites. Fluvastatin showed dose-dependent superoxide anion scavenging activity in the NADH/phenazine methosulphate (PMS)/nitroblue tetrazolium (NBT) system, and the effect was as potent as the reference antioxidant, trolox, which is a water-soluble alpha-tocopherol derivative. The superoxide anion scavenging activities of the major metabolites of fluvastatin (M2, M3, M4, M7) were also determined in this system. All of these metabolites showed the activity. In particular, M2 and M3, which possess a phenolic hydroxyl group at the 5 or 6-position of the indole moiety, respectively, showed 3 times stronger activities than that of fluvastatin. Further, we also determined the effects of fluvastatin, M2 and M3 on phorbol myristate acetate (PMA)-induced superoxide anion generation in human peripheral blood polymorphonuclear leukocytes (PMN). The compounds tested also showed a depressing effect on the amount of superoxide anion in this system. We suggest that fluvastatin and its metabolites have the potential to protect cells or lipids from oxidative modification mediated by superoxide anion.

In vitro inhibitory effects of the optical isomers and metabolites of fluvastatin on copper ion-induced LDL oxidation

Fluvastatin is a synthetic hypolipidemic drug which inhibits 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase. We compared in vitro the antioxidative effects of two enantiomers (3R, 5S and 3S, 5R) of fluvastatin, which is clinically used as a racemic mixture, on copper ion-induced oxidation of human low-density lipoprotein (LDL). Although 3R,5S-enantiomer of fluvastatin has 30-fold stronger inhibitory activity on HMG-CoA reductase than its optical counterpart, the antioxidative effects of these enantiomers on copper ion-induced LDL oxidation were similar. The antioxidative effects of the metabolites of fluvastatin (M2, M3, M4 and M7) on the copper ion-induced LDL oxidation were also investigated. All the metabolites tested showed an inhibitory effect on this system. Among them, the effects of M2 and M3, which have a phenolic hydroxyl group in each indole moiety, were strong and their potencies were 30-50 times greater than that of fluvastatin. We conclude that not only 3R,5S-enantiomer of fluvastatin but also its optical counterpart and the metabolites also have a potential to show the anti-atherosclerotic effect through their antioxidative activities on lipid peroxidation.

An in vitro study of the hydroxyl radical scavenging property of fluvastatin, and HMG-CoA reductase inhibitor

We investigated the in vitro hydroxyl radical scavenging activity of fluvastatin, a 3-hydroxy-3-methylglutaryl (HMG)-CoA reductase inhibitor. Fluvastatin showed hydroxyl radical scavenging activity as potent as that of dimethylthiourea and alpha-tocopherol, which are well-known respectively, as a hydroxyl radical scavenger and a natural antioxidant. Since this effect was not observed in other HMG-CoA reductase inhibitors, such as pravastatin and simvastatin, the scavenging effect of fluvastatin on hydroxyl radicals would not be a common property of HMG-CoA reductase inhibitors, but is derived from the unique chemical structure of fluvastatin. The hydroxyl radical scavenging activities of human metabolites of fluvastatin were also determined. All the tested metabolites possessing the fluorophenyl indole moiety showed activity. Among them, the metabolites which possess a phenolic hydroxyl group on the indole moiety showed stronger effects than that of fluvastatin. We suggest that the fluorophenyl indole moiety of fluvastatin is important for manifestation of the activity and that the phenolic hydroxyl group enhances the potency.

Protective effect of fluvastatin sodium (XU-62-320), a 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitor, on oxidative modification of human low-density lipoprotein in vitro

We investigated the protective effect of fluvastatin sodium on the oxidation of low-density lipoprotein (LDL) induced in vitro by copper ions. The extent of lipid peroxidation was assessed by monitoring the increase of UV absorbance at 234 nm, which is the peak absorbance of a conjugated diene. Fluvastatin sodium (1-30 microM) not only prolonged the lag time of oxidation in the initiation step, but also decreased the rate of oxidation in the propagation step, both concentration dependently. Fluvastatin sodium and alpha-tocopherol showed an additive effect when both compounds were added before oxidation. However, when the lag time was prolonged initially by alpha-tocopherol, and fluvastatin sodium and alpha-tocopherol, were further added into the reaction mixture at the end point of the lag phase, fluvastatin sodium still showed an antioxidative effect, whereas alpha-tocopherol showed a pro-oxidative effect. Therefore, the antioxidative property of fluvastatin sodium differs from that of alpha-tocopherol. In this experiment, as neither the double bond-reduced derivative of fluvastatin sodium nor pravastatin sodium showed any protective effect, we concluded that the antioxidative effect of fluvastatin sodium is not a common property of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors, but may be derived from its unique chemical structure. Since the oxidative modification of LDL plays an important role in the genesis of atherosclerosis, fluvastatin sodium may help reduce the risk of atherosclerosis, not only by reducing plasma LDL levels but also by protecting LDL from oxidative modification.

[Concentrations of 5-fluorouracil (5-FU) in serum and tissues at venous injection of tegafur or 5-FU--clinical study on colorectal cancer]

Tissue and serum concentrations of 5-fluorouracil (5-FU) after daily slow venous injection of tegafur or 5-FU for 5 days were measured. The serum concentration of 5-FU elevated to the highest level 6 hours after the venous injection (mean: 30 ng/ml). Compared with the tegafur injection, the serum concentration of 5-FU elevated to a higher peak level 6 hours after the 5-FU injection (mean: 827 ng/ml). The serum concentration of 5-FU after the tegafur injection tended to be maintained longer than after the 5-FU injection. When tegafur was injected, the concentration of 5-FU in cancer tissue or lymphnodes was significantly higher than in normal tissue. On the other hand, no significant difference was detected among the concentrations of 5-FU in the above three tissues when 5-FU was injected. Moreover, a significantly higher concentration of 5-FU in lymphnodes was caused by the tegafur injection compared to the 5-FU injection.

Precise frequency-difference measurement between the 1.66-mum transitions of methane

We determined 66 frequency differences (FD's) between rovibrational lines of methane at the 1.66-mum region. Following the technique developed by Nakagawa et al.[Opt.Lett.20, 410 (1995)], we measured the FD's as the optical beat frequency between two external-cavity diode lasers locked at 1-MHz-wide saturated absorption dips of the methane lines. Even though the methane lines often overlap in Doppler-limited resolution, the spectrometer that we use resolves them and determines their FD's with better than 40-kHz precision. This fact demonstrates that the methane lines are promising candidates for frequency reference and that this technique has great potential for high-resolution molecular spectroscopy.

Pharmacologically active components of Todopon Puok (Fagraea racemosa), a medicinal plant from Borneo

The lignans of (+)-pinoresinol, (+)-epipinoresinol, (+)-lariciresinol and (+)-isolariciresinol together with phenols such as syringaldehyde and 7,8-dihydro-7-oxy-coniferyl alcohol were isolated from Todopon Puok (Fagraea racemosa Jack ex Wall), a medicinal plant from Borneo, using a bioassay of the relaxation effect on norepinephrine (NE)-induced contraction in rat aortic strips. The plant extract also exhibited analgesic properties in the acetic acid-induced writhing and tail pressure tests in mice, with the activity being concentrated in the lignan fraction. (+)-Pinoresinol showed analgesic effect on writhing symptoms in mice which were dose-dependent, and produced local anesthesia in guinea pigs.

[Antitumor effect of UFT against differentiated thyroid cancer]

We have determined the levels of 5-FU, tegafur and uracil in the thyroid cancer and normal thyroid tissue in the patients with differentiated carcinoma who were administered UFT 600 mg/day p.o. preoperatively for six days. 5-FU and uracil levels in the thyroid cancer tissue were significantly higher than in normal thyroid tissue. However, tegafur level did not show significant differences in any tissues. Two cases with differentiated carcinoma, which resulted in PR after prolonged administration of UFT were presented. These findings suggest that oral administration of UFT for a long term is a useful treatment for advanced differentiated thyroid cancer.

[Efficacy of the treatment of gastric cancer as neo-adjuvant chemotherapy of 48 hour continuous intravenous infusion of 5-fluorouracil (5-FU) with leucovorin (LV)]

A 51-year-old female with inoperable gastric cancer and with infiltration of pancreatic tail diagnosed by abdominal CT was treated with leucovorin (LV) and 5-fluorouracil (5-FU). The regimen was: LV 30 mg/body/24 hr prior to 5-FU 1,000 mg/m2/day for 48 hrs. This treatment was repeated 6 times. After treatment, the size of tumor decreased so that the patient was able to be operated (Total gastrectomy with partial distal pancreatico-splenectomy). During the treatment, patient showed no side effect except for slight nausea. This neo-adjuvant chemotherapy might be a recommendable treatment of advanced gastric cancer.

Malignant "triton" tumor in the thyroid--a case report

This report presents a very rare case of a malignant "Triton" tumor developing in the thyroid. Although malignant "Triton" tumors have often been known to develop in cases of neurofibromatosis, Von Recklinghausen's disease, this patient showed no clinical evidence of that disease. Total thyroidectomy including left standard radical neck dissection was followed by postoperative irradiation to the neck. Despite this, local and distant metastases developed four months after treatment and the recurrent foci did not respond to chemotherapy or irradiation. The clinical course of this case mimicked that of anaplastic carcinoma of the thyroid and interestingly, a minimal lesion of papillary adenocarcinoma was found to exist concurrently in the thyroid gland of this patient.

[Efficacy of a 48-hour infusion of 5-fluorouracil in patients with stage IV gastric cancer after palliative gastrectomy]

Efficacy of a 48-hour infusion of 5-FU in patients with stage IV gastric cancer was investigated. A one-cycle regimen consisted of a 48-hour infusion of 5-FU (30 mg/kg/24 hours) every week for 6 weeks. Fourteen patients with stage IV gastric cancer who underwent absolutely non-curative gastrectomy, received 5-FU infusion postoperatively. Ten of the 14 received more than 2 cycles. Survival rates in these patients (group I) were evaluated by Kaplan-Meier method and compared with those of matched pair controls (group II) who received other anticancer agents. Side effects were generally mild. Nausea during infusion was observed in only 3 cases. The 50% survival period was 393 days in group I and 135 days in group II, respectively. The survival curve in group I was significantly higher than in group II (p = 0.05). From these results, this treatment is considered to be very effective.

Clear cell carcinoma of the thyroid. A case report

A rare case of clear cell carcinoma of the thyroid is presented herein. A 31-year-old male had a large soft tumor in the right lobe of the thyroid which showed a hot nodule on scintigram with 99mTc. A right hemithyroidectomy was thus performed after the preoperative diagnosis of a functioning tumor had been made. At surgery, a tiny nodule behind the tumor was found and the histopathological diagnoses of the large tumor and the tiny nodule were clear cell carcinoma and papillary carcinoma, respectively. The thyroglobulin stain was positive in the cytoplasm of many clear cells and scattered colloid. This patient has been well without any evidence of recurrence over the past five years following surgery. The biological characteristics of clear cell carcinoma of the thyroid are discussed in this report.

Local recurrence of breast cancer: treatment of nine patients with a recurrence in the skin flap of the chest wall

From 1975 through 1985, nine patients with a local recurrent lesion (LRL) of breast cancer to the skin flap of the chest wall were treated. Four had undergone primary mastectomies in our clinic and the other five were referred from other surgeons, following signs of recurrence. Aggressive topical therapy, such as resection or irradiation, proved effective in eradicating the LRL in all cases, thereby indicating that topical therapy is useful for improving quality of life. Adjuvant systemic chemo-immuno-endocrine therapy is also required for patients with LRL, to increase longevity. Seven of the patients died of a distant metastasis within 66 months after the onset of LRL.

Adrenocortical carcinoma responded to treatment with o,p'-DDD--a case report

A case of a huge inoperable adrenocortical carcinoma which secreted testosterone without characteristic symptoms was treated with o,p'-DDD (2,2-bis(2-chlorophenyl-4 cholorophenyl) 1,1-dichloroethane). With this therapy, the tumor decreased in size which was confirmed by the computed tomography (CT). Eighteen months later, however, lethargy and logopathy appeared and the tumor grew again rapidly with the withdrawal of o,p'-DDD performed for the evaluation of these mental disturbances. The tumor then diminished gradually in size soon after the treatment was resumed and the above unfavorable symptoms were not developed again with the combined administration of a central nervous stimulant. During o,p'-DDD treatment, plasma testosterone and estrogen decreased, and plasma aldosterone also decreased but within the normal range. Plasma cortisol also tended to decrease despite hydrocortisone was administered. Plasma adrenocorticotropic hormone (ACTH) was maintained within the normal range for the first six months but then increased gradually. It decreased and became normal with the additional administration of hydrocortisone. The patient's normal menstruation at the preadministrative stage changed to oligomenorrhea, then amenorrhea after the treatment, but no endocrinological sign except for the menses was observed during the treatment.

Pheochromocytoma without specific symptoms

A 72-year-old Japanese woman with pheochromocytoma, who had had no characteristic symptoms was treated. A large retroperitoneal tumor was discovered incidentally by sonographic examination for mild upper abdominal pain and, with CT-scan and abdominal angiography confirmed that the tumor originated in the right adrenal gland. The tumor was suspected of being a pheochromocytoma because preoperative laboratory examinations revealed only a mild elevation of daily urinary excretions of adrenaline and noradrenaline. Provocation tests for pheochromocytoma and even angiographic examination revealed no diagnostic change in serum levels of catecholamines and distinctive clinical signs were nil. Thus, surgery was performed without preoperative prescription of any catecholamine blockade. During the surgery, the blood pressure and pulse rate fluctuated considerably. A non-functioning pheochromocytoma detected incidentally must be preoperatively managed as a functioning one, even in the absence of specific symptoms of pheochromocytoma.