Antibacterial activity of plant extracts from azuki beans (Vigna angularis) in vitro.

This study was undertaken to examine the antimicrobial property of azuki beans (Vigna angularis). The water extracts of green, black and red colored azuki beans showed antibacterial effects against Staphylococcus aureus, Aeromonas hydrophila and Vibrio parahaemolyticus. In contrast, the extract of white azuki beans showed no inhibition towards any of the microorganisms examined. The extracts of colored azuki beans contained larger amounts of polyphenols including proanthocyanidins than the extracts of white azuki beans. The counts of S. aureus cells, inoculated in the medium containing the extracts of colored azuki beans, were significantly reduced in comparison with those of control and white azuki beans after 24 h (p < 0.05). These results suggest that polyphenols including proanthocyanidins in colored azuki beans may be responsible for their antibacterial activity.

Interaction of mastoparan with membranes studied by 1H-NMR spectroscopy in detergent micelles and by solid-state 2H-NMR and 15N-NMR spectroscopy in oriented lipid bilayers.

Several complementary NMR approaches were used to study the interaction of mastoparan, a 14-residue peptide toxin from wasp venom, with lipid membranes. First, the 3D structure of mastoparan was determined using 1H-NMR spectroscopy in perdeuterated (SDS-d25) micelles. NOESY experiments and distance geometry calculations yielded a straight amphiphilic alpha-helix with high-order parameters, and the chemical shifts of the amide protons showed a characteristic periodicity of 3-4 residues. Secondly, solid-state 2H-NMR spectoscopy was used to describe the binding of mastoparan to lipid bilayers, composed of headgroup-deuterated dimyristoylglycerophosphocholine (DMPC-d4) and dimyristoylphosphatidylglycerol (DMPG). By correlating the deuterium quadrupole splittings of the alpha-segments and beta-segments, it was possible to differentiate the electrostatically induced structural response of the choline headgroup from dynamic effects induced by the peptide. A partial phase separation was observed, leading to a DMPG-rich phase and a DMPG-depleted phase, each containing some mastoparan. Finally, the insertion and orientation of a specifically 15N-labeled mastoparan (at position Ala10) in the bilayer environment was investigated by solid-state 15N-NMR spectroscopy, using macroscopically oriented samples. Two distinct orientational states were observed for the mastoparan helix, namely an in-plane and a trans-membrane alignment. The two populations of 90% in-plane and 10% trans-membrane helices are characterized by a mosaic spread of +/- 30 degrees and +/- 10 degrees, respectively. The biological activity of mastoparan is discussed in terms of a pore-forming model, as the peptide is known to be able to induce nonlamellar phases and facilitate a flip-flop between the monolayers.

FR901469, a novel antifungal antibiotic from an unidentified fungus No.11243. II. In vitro and in vivo activities.

FR901469 is a water-soluble macrocyclic lipopeptidolactone (C71H116N14O23) that has inhibitory activity against 1,3-beta-glucan synthase and exhibits in vitro and in vivo antifungal activity against both Candida albicans and Aspergillus fumigatus. The MICs of FR901469 against Candida albicans FP633 and Aspergillus fumigatus FP1305 in a micro-broth dilution test were 0.63 and 0.16 microg/ml, respectively. FR901469 showed excellent efficacy by subcutaneous injection against both Candida albicans and Aspergillus fumigatus in a murine systemic infection mode, with ED50s of 0.32 and 0.2 mg/kg, respectively. This compound also showed potent anti-Pneumocystis activity in the nude mice model with experimental Pneumocystis pneumonia. The hemolytic activity of FR901469 towards mouse red blood cells, is about 30-fold weaker than that of amphotericin B.

Novel antiarthritic agents with 1,2-isothiazolidine-1,1-dioxide (gamma-sultam) skeleton: cytokine suppressive dual inhibitors of cyclooxygenase-2 and 5-lipoxygenase.

Various 1,2-isothiazolidine-1,1-dioxide (gamma-sultam) derivatives containing an antioxidant moiety, 2,6-di-tert-butylphenol substituent, were prepared. Some compounds, which have a lower alkyl group at the 2-position of the gamma-sultam skeleton, showed potent inhibitory effects on both cyclooxygenase (COX)-2 and 5-lipoxygenase (5-LO), as well as production of interleukin (IL)-1 in in vitro assays. They also proved to be effective in several animal arthritic models without any ulcerogenic activities. Among these compounds, (E)-(5)-(3,5-di-tert-butyl-4-hydroxybenzylidene)-2-ethyl-1, 2-isothiazolidine-1,1-dioxide (S-2474) was selected as an antiarthritic drug candidate and is now under clinical trials. The structure-activity relationships (SAR) examined and some pharmacological evaluations are described.

Effects of capsaicin on biliary free fatty acids in rats.

The effects of capsaicin, a major pungent agent of capsicum fruits, on biliary free fatty acids (FFAs) were studied in male rats. Animals were dosed 100 mg/kg capsaicin after the administration of olive oil, and the bile was obtained for 6 hours continuously after dosing with capsaicin for analysis of FFAs using HPLC methods. Capsaicin significantly decreased the total biliary FFA concentration in the animals which had been previously increased by the administration of olive oil. The main FFAs in the bile of control rats are lauric and palmitic acids, followed by linoleic, oleic, stearic and palmitoleic acids. Capsaicin alone decreased the values of these main FFAs. While lauric, palmitic, linoleic, stearic and arachidonic acids were increased significantly by the treatment with olive oil, elevation of these FFAs was inhibited by the treatment with capsaicin.

Effects of capsaicin on serum triglycerides and free fatty acid in olive oil treated rats.

Male rats were dosed with capsaicin after the administration of olive oil, and the serum was obtained for analysis of triglycerides and free fatty acids (FFAs). The serum triglycerides level was increased at 2 and 4 hours after olive oil treatment. On the other hand, capsaicin significantly lowered this increase after 4 hours of treatment in the dosage of 100 mg/kg. Total FFA level was also lowered which had previously been increased by the administration of olive oil after 2 hours of treatment, solely the increase in oleic acid (C18:1) levels was lowered among the FFA. The present results indicated that capsaicin decreased only the components of the dosed olive oil. Furthermore, elevation of the serum total FFA concentration was significantly inhibited 2 or 4 hours after the treatment but not at 8 hours, suggesting that a single high dose treatment with capsaicin may inhibit the absorption of lipid in the gastrointestinal tract.

Orientational behavior of phospholipid membranes with mastoparan studied by 31P solid state NMR.

Solid state 31P NMR spectroscopy was used to study the perturbing effect of the wasp venom peptide mastoparan (MP) on lipid bilayers composed of dimyristoylphosphatidylcholine (DMPC) and dimyristoylphosphatidylglycerol (DMPG). The 31P chemical shift anisotropy of multilamellar vesicles decreased with increasing peptide concentration, indicating that MP interacts strongly and selectively with the charged DMPG head group. Macroscopically oriented MP-lipid samples between glass plates were studied by 31P NMR as a function of tilt angle. These spectra showed the coexistence of orientation-dependent lamellar signals as well as an isotropic peak, suggesting that MP can induce non-lamellar phases in DMPC/DMPG membranes.

Promotion of tyrosinase folding in COS 7 cells by calnexin.

To understand the process of expression of tyrosinase, a key enzyme of melanogenesis, we examined its maturation in the endoplasmic reticulum (ER) by using a heterogeneous expression system. When human tyrosinase cDNA was introduced into COS 7 cells, tyrosinase activity was minimally detected. Immunofluorescence study revealed that tyrosinase was immunolocalized in the nuclear rim, the reticular network, and the punctuated structures. Because a cytoplasmic tail of tyrosinase-gene family protein functions as a lysosomal targeting signal in non-melanocytic cells, and immature and/or misfolded molecules are selectively retained in the ER, the observed localization suggested the inefficient maturation in the COS 7 cells. We thus examined if supplementation of calnexin, a membrane-bound chaperone with affinity for oligosaccharide-processing intermediates containing monoglucose, could improve the process. As expected, the activity was enhanced approximately 2-fold by co-transfection of cDNA encoding calnexin. In contrast, co-transfection of the cytosolic tail-free calnexin, which inhibits calnexin function by allowing premature egress of its ligands from the ER, suppressed expression of this enhanced tyrosinase activity. When alpha-glucosidase activity, which is required for calnexin function, was inhibited by castanospermine (CST) treatment, expression of tyrosinase activity was completely abolished. To confirm the direct involvement of calnexin in tyrosinase maturation, the interaction of calnexin with tyrosinase was examined. Immunoprecipitation of calnexin from extracts of [35S]methionine labeled cells with anti-calnexin antibody revealed that the association is highest immediately after the pulse and that nascent tyrosinase is gradually dissociated upon chase. The association was completely inhibited when CST was included in the medium. Hence, we suggest that the proper folding of tyrosinase is largely dependent on its direct interaction with calnexin for the determined duration in the ER.

Intracellular calcium changes and chemosensitivities of human epidermoid carcinoma cell lines after exposure to cisplatin.

In order to elucidate the mechanisms of cisplatin (cis-diamminedichloroplatinum; CDDP)-resistant tumor cells, we previously established a CDDP-resistant KB cell line (KBrc cells) from a parental KB cell line derived from epidermoid carcinoma (KB cells). The KBrc cells were resistant to 5 kinds of platinum (Pt) drugs. Intracellular Pt concentrations in KBrc cells were lower than in KB cells. Decrease of intracellular Pt concentrations was one of the CDDP-resistant mechanisms. When we measured changes of intracellular calcium ion concentration ([Ca2+]i) during exposure to high-dose CDDP, a sustained elevation of the [Ca2+]i level was observed in the KB cells. These results suggest that the mechanisms underlying CDDP resistance involve changes in calcium channels and an alteration of calcium homeostasis in the tumor cell line.

Increase in the peripheral lymphocyte populations expressing CD54 (ICAM-1) after hyperthermic isolated limb perfusion in patients with malignant melanoma: an analysis of four cases.

The lymphocytes isolated from perfused or non-perfused circulations before, during, and after hyperthermic isolated limb perfusion (HILP) in the four patients with malignant melanoma were analysed for the expression of CD54 (ICAM-1), CD58 (LFA-3), CD4, CD8, HLA class I and class II in order to investigate the mechanism(s) of the activation of such immunocompetent cells as natural killer (NK)-cells or T-lymphocytes by HILP. It was thus found that the lymphocyte populations expressing CD54 increased significantly 1 day after HILP in the four patients examined. The lymphocyte populations expressing CD58 apparently increased. It was also found that the NK-cell and T-lymphocyte activities increased during or after HILP in the present four cases as observed previously in the other melanoma patients. These results indicate that our HILP system may augment the immunological activities through the mechanisms of the induction of CD54 or CD58 expression in the peripheral lymphocytes of the melanoma patients who receive HILP.

Synthesis and evaluation of novel fluorinated methotrexate derivatives for application to rheumatoid arthritis treatment.

An ongoing search for new antifolate drugs useful against rheumatoid arthritis (RA) led us to prepare new methotrexate (MTX) derivatives containing enantiomerically pure L-erythro- or L-threo-gamma-fluoroglutamic acid. The derivatives in which the phenyl ring was replaced by a 3'-substituted phenyl or methylthiophene ring showed potent immunosuppressive activities, including in vitro inhibition of mitogen responses to both T and B cells and in vivo inhibition of antibody production in mice. These compounds also exhibited inhibitory activity in adjuvant arthritis in rats. Their toxicity was lower than that of MTX, which was probably due to the strong electronegativity of fluorine, which increases the acidity of the gamma-carboxyl group and thereby decreases polyglutamylation in normal cells. These results revealed the potential of the fluorinated MTX derivatives as candidate drugs for the treatment of RA.

Experimental approaches for the treatment of murine B16 melanomas of various sizes. I: Local injection of ethanol with a combination of interleukin-2 or microwaval hyperthermia for B16 melanomas with a size of less than 7 mm in diameter.

The effects of local absolute ethanol injection combined with administration of interleukin-2 (IL-2) or microwaval hyperthermia in murine B16 melanomas with a size of approximately 7 mm in diameter were investigated. The groups of melanoma-burdened mice treated with both local ethanol injection and local or intra-abdominal administration of IL-2 showed clear suppression of any recurrence of melanoma once the melanomas had been destroyed by ethanol injection and a concomitant prolongation of the survival times. Also, local injection of ethanol in combination with local microwaval hyperthermia at 43 degrees C for 15 min twice a week caused complete cures in B16 melanomas with a size of less than 7 mm in diameter. The infiltrations of T lymphocytes and NK cells were augmented in the melanomas treated with ethanol injection and local injection of IL-2. However, the melanomas treated with ethanol injection and intra-abdominal injection of IL-2 hardly showed any infiltration of such immune cells, although the growth of melanomas was effectively suppressed. In the case of treatment with ethanol and hyperthermia, slight infiltration of NK cells was observed in the melanoma nests as well as in the interstitials. Thus, the direct injection of absolute ethanol in combination with IL-2 or microwaval hyperthermia is effective or even curative in the treatment of murine B16 melanomas with a size of less than 7 mm in diameter.

Experimental approaches for the treatment of murine B16 melanomas of various sizes. II: Injection of ethanol with combinations of beta-interferon and microwaval hyperthermia for B16 melanomas with a size of greater than 10 mm in diameter.

Although ethanol injection in combination with microwaval hyperthermia and systemic administration of interleukin-2 was found to be very effective in suppressing the growth of B16 melanoma nodules with a size of less than 7 mm in diameter in our previous experiments, the growth of B16 melanomas with a size of greater than 10 mm in diameter was very difficult to control with any of the therapeutic modalities examined. In subsequent experiments, we investigated whether ethanol injection (150 microliters/injection) in combination with local injection of beta-interferon (2 x 10(4) IU/injection) and local microwaval hyperthermia at 43 degrees C for 15 min was able to suppress the growth of melanoma nodules and to prolong survival times of melanoma-burdened mice. The results were that we successfully suppressed the growth of melanoma nodules of that size for the first time with combinations of the therapeutic modalities described above. Infiltration of immunocompetent cells such as T lymphocytes and NK cells was clearly observed in the melanoma tissues treated with the therapeutic combination. These experimental results should be applied to the treatment of human melanomas in advanced stages which have no indications for surgical operation.

Kinetics of immunological parameters in patients with malignant melanoma treated with hyperthermic isolated limb perfusion.

Kinetics of immunological parameters such as natural killer (NK) cell activity and tritium-thymidine uptake rate of T lymphocytes by phytohemagglutinin stimulation were investigated using peripheral leukocyte fractions of melanoma patients treated with hyperthermic isolated limb perfusion (HILP). Also, serum concentrations of soluble intercellular adhesion molecule-1 (sICAM-1) were quantified during and after HILP. It was found that NK cell activity was augmented during HILP, and T lymphocyte function was stimulated 24 h and 1 week after HILP with statistical significance. NK cell activities in the cells isolated from perfused and non-perfused circulations were equally augmented during HILP in two patients examined. Serum concentrations of sICAM-1 in the patients who received HILP also increased 24 h or even 1 week after HILP. The stimulation of these immune competent cells and upregulation of sICAM-1 by HILP were independent of the stages of melanoma patients at the time of HILP or the doses of agents which were used for the infusion during HILP. The origin of cells which shed sICAM-1 into the serum of the patients who received HILP remains to be further investigated.

[Dermatological findings in the annual examination of the patients with Yusho in 1995-1996].

We reported the grades of severity of skin symptoms and the blood PCB patterns and concentrations in Yusho patients who had the annual examinations in 1995 and 1996. The skin severity grades and the skin severity scores showed the same tendency as recorded in the last 10 years. Yusho patients who were scored as more than 6.7 were around 8% of the total patients both in 1995 and 1996. The correlation between the blood PCB patterns and the severity grades of skin symptoms was clear. Thus, the mean skin severity scores in patients showing A pattern were higher than those in patients showing either B or C pattern. The same results were obtained when the correlation between the blood PCB patterns and the skin severity grades was analyzed. Patients whose ages were 50-70 years old were found to show the highest blood PCB concentrations and the skin severity scores.

Increase in shedding of intercellular adhesion molecule-1 in human malignant melanoma cell lines treated with hyperthermia in vitro.

Human malignant melanoma cell lines were found to increase shedding of soluble intercellular adhesion molecule-1 (sICAM-1) into the culture medium when the cells were treated with hyperthermia at 41-43 degrees C for 3-6 hr in vitro. The content of ICAM-1 in the cell lysate was also found to be increased after hyperthermia. The increased rate of ICAM-1 concentration in the cells was at maximum when they were incubated at 41 degrees C for 3 hr. Also, the melanoma cell lines heat-treated at 41 degrees C showed more intense immunofluorescence in the ICAM-1 expression on the cell surface. It remains to be investigated further whether the effects of hyperthermia on the ICAM-1 expression in melanoma cells is to augment membrane ICAM-1 expression, which in turn leads to shedding of soluble ICAM-1 or only to acceleration of shedding of sICAM-1 by unknown mechanisms.

Two cases of metastatic malignant melanoma of the lower limb treated with hyperthermic isolated limb perfusion and concomitant infusion of either carboplatin or beta-interferon.

Two cases of metastatic malignant melanoma of the lower limb who were treated successfully with hyperthermic isolated limb perfusion are reported. One patient was infused with cisdiammine (1.1-cyclobutanedicarboxylate) platinum (II) (carboplatin, Paraplatin, Bristol-Myers Squibb Company, New Jersey, USA), and the other was infused with human natural beta-interferon (Feron, Toray, Tokyo, Japan), via the external iliac artery. The first case showed a remarkable suppression of the growth of multiple metastatic melanoma nodules associated with numerous melanophage infiltrations, as shown histopathologically after the operation. The patient's serum level of 5-S-cysteinyl dopa decreased for the two months following the treatment. In the second case, new formation of metastatic melanoma nodules was completely suppressed for up to 12 months following the operation. Analysis of immunological parameters showed that the number of peripheral CD8+ lymphocytes gradually and constantly increased after the operation, while that of CD4+ lymphocytes transiently increased and then returned to the pre-operative level. Natural killer activity transiently decreased to a slight degree 4 days after the operation and then returned to the pre-operative level 21 days after the operation. Side effects, such as nausea, vomiting and leg discomfort, were seen in the patient (Case 1) treated with carboplatin, but were completely reversible. These results suggest that hyperthermic isolated limb perfusion with concomitant infusion of carboplatin or beta-interferon is effective in suppressing the growth of metastatic malignant melanomas of the lower limb.

Clinical trial of a combination of rice bran fiber and cholestyramine for promotion of fecal excretion of retained polychlorinated dibenzofuran and polychlorinated biphenyl in Yu-Cheng patients.

A clinical trial using the combination of rice bran fiber (RBF) and cholestyramine (CHO) was carried out on Yu-Cheng patients in 1993-1994. By the analysis of blood and stool samples collected from the patients before and after (or during in the case of stool), it was verified that the administration of RBF and CHO is effective for excretion of polychlorinated biphenyl (PCB) (p < 0.05) and polychlorinated dibenzofuran (PCDF), especially 2, 3, 4, 7, 8-pentachlorodibenzofuran (p < 0.05). However, the degree of effectiveness varied upon individual patients from 60 to 160% for 2, 3, 4, 7, 8-pentachlorodibenzofuran, from 30 to 110% for 1, 2, 3, 4, 7, 8-hexachlorodibenzofuran and from 50 to 190% for PCB, respectively.

[Levels of PCDDs, PCDFs and coplanar PCBs in the blood and stool of Taiwanese Yu-Cheng patients].

Levels of PCDDs, PCDFs and coplanar PCBs were measured in the blood and stool obtained from seventeen patients with Yu-Cheng in Taiwan. The average total concentrations of PCDDs, PCDFs and coplanar PCBs in the blood collected from Yu-Cheng patients in January 1993 and August 1994 were 590 and 570 pg Toxic Equivalents (TEQs)/g lipid, respectively. The concentrations of PCDDs, PCDFs and coplanar PCBs in the blood of patients were 21, 540 and 10 pg TEQs/g fat, respectively. On the other hand, the fecal excretion of PCDDs, PCDFs and coplanar PCBs were 26, 720 and 15 pg TEQs/day, respectively. The composition of congeners in the feces was quite similar to the one in the blood. The half lives were estimated as 9.1 and 8.6 years for 2, 3, 4, 7, 8-pentachlorodibenzofuran and 1, 2, 3, 4, 7, 8-hexachlorodibenzofuran based on fecal excretion, respectively.

[Dermatological findings in the annual examination of the patients with Yusho in 1993-1994].

We reported the grades of severity of skin symptoms and the blood PCB patterns and concentrations in Yusho patients who were examined in the annual examinations in 1993 and 1994. The skin severity grades and skin severity scores showed the same tendency as recorded in the last 15 years. Approximately 20% of the patients, however, claimed the tendency of recurrence of skin infections and/or infected epidermal cysts, and still approximately 30% of the patients exhibited acneiform eruptions. Ten patients recorded with more than 6 points of skin severity scoring in these examinations were further investigated their initial skin severity grades and blood PCB patterns and concentrations. It was found that most of their blood PCB patterns showed the A pattern, and the level of the blood PCB in one patient was 55.5 ppb in the initial stage. Five patients out of 10 patients still have more than 10 ppb of blood PCB concentration. Thus, it is concluded that small populations of Yusho patients still have active skin symptoms with considerable blood PCB levels even at present.