Pulp ablation therapy by inductive heating: heat generation characteristics in the pulp cavity.

OBJECTIVE AND METHODS: This study was performed to clarify the usefulness of inductive heating system for the new endodontic therapy. Dextran magnetite complex (DM) suspensions were injected into the root canal of a permanent tooth, and the tooth was heated up to about 55.0 degrees C by alternating-current magnetic field. RESULTS AND CONCLUSION: The time until the temperature in the pulp cavity reached 55.0 degrees C was 328 +/- 26 s (mean +/- s.d., n = 8) in the 56 mg as Fe ml(-1) of DM concentration. The temperature in the pulp cavity could be maintained at 53.5-59.0 degrees C for 1200 s by changing the magnetic field intensity safely, while temperature elevations of the dental surface on the coronal and apical sides were 4.9 degrees and 3.7 degrees C, respectively. Thus, this inductive heating system, which has the possibility of selective heating, might be useful for eliminating residues of pulp as a new ablation therapy.

Antitumor effect of new local hyperthermia using dextran magnetite complex in hamster tongue carcinoma.

OBJECTIVE: This study was performed to clarify the usefulness of Dextran magnetite (DM) for the oral cancer hyperthermia. METHODS: Tumors were induced in golden hamster tongue by 9,10-dimethyl 1-1,2-benzanthracene (DMBA) application. DM suspension was locally injected into the tumor-bearing tongue and tongues were heated up to 43.0-45.0 degrees C, by AC magnetic field of 500 kHz. RESULTS: The average time taken for the temperature to rise to 43.0 degrees C or above was 162 s (n = 17) at the margin of the tumor and 420 s (n = 17) at the center of the tumor. According to the tumor volume, the time required for an increase in the central temperature of tumor to 43.0 degrees C tended to be prolonged. Both temperatures could be maintained at approximately 43.0-45.0 degrees C for 30 min. The inhibition of the growth of tongue carcinoma in the four-time heating group was significantly greater than in the control group (P < 0.01). Moreover, the survival rate was significantly higher in the heated groups than in the control group (P < 0.01). Histological examination revealed a brown uniform DM accumulation at the stroma in the margin of the tumors. Many of tumor cells disappeared at the site adjacent to this accumulation. CONCLUSION: These results strongly suggest the usefulness of this local hyperthermic system in the oral region that is accessible to this treatment.

New local hyperthermia using dextran magnetite complex (DM) for oral cavity: experimental study in normal hamster tongue.

The possibility of dextran magnetite complex (DM) as a new hyperthermic material was examined in this study. DM suspension of 56 mg ml(-1) iron concentration was locally injected into the normal tongue of golden hamster. DM injected tongues were heated by 500 kHz alternating current (AC) magnetic field and its serial changes in temperature were recorded at 30-s intervals. The temperature of DM injected tongue was maintained at about 43.0-45.0 degrees C for 30 min by changing the AC magnetic field intensity. While temperature elevations of the contralateral tongue and the rectum were only of minor degree. In experiment on the extent of heating area, there was correlation between volume of black stain area and amount of the injected DM suspension (Y = - 18.1 + 1.94X, r = 0.931, P < 0.0001, n = 9 ). Histological examination after heating revealed brown uniform DM accumulation in the connective tissue between fibers of the tongue muscle. Except for vascular dilatations, no tissue damage was seen in the heated tongue. Thus, DM which has the possibility of selective and uniform heating in local hyperthermia might be useful for oral cancer therapy.

Nitric oxide-mediated antitumor activity induced by the extract from Grifola frondosa (Maitake mushroom) in a macrophage cell line, RAW264.7.

We have investigated D-fraction (MDF) extracted from Grifola frondosa (Maitake mushroom) on the inducible nitric oxide synthase (iNOS)-mediated nitric oxide (NO) production in RAW264.7 (RAW) cells, a murine monocyte/macrophage cell line, with special reference to antitumor activity of MDF against human hepatoma-derived huH-1 cells. MDF could induce iNOS mRNA expression in RAW cells in a dose range of more than 30 microg/ml, but the effect of 10 microg/ml of MDF was negligible. The iNOS mRNA expression induced by 100 microg/ml of MDF was 6 hrs later, but lasted for a longer time than that of lipopolysaccharide (LPS), a representative iNOS inducer. Although iNOS mRNA levels in MDF-stimulated cells were almost equal to LPS-stimulated cells at the peak time, the cumulative amount of nitrite was only about 50% compared with that of LPS-treated cells. When huH-I cells were cultured in MDF containing media in a 24-well plate with inserted porous bottom in the presence or absence of RAW cells, the viability of huH-1 cells decreased significantly only in the presence of RAW cells in MDF dose-dependent manner. This antitumor activity of RAW cells in the presence of MDF was abolished or attenuated by the addition of L-NAME, a NOS inhibitor, confirming that this phenomenon is due to iNOS-mediated NO production by RAW cells, but not direct cytotoxic activity of MDF against huH-1 cells. These data suggest that MDF is a novel inducer for iNOS which contributes at least in part to antitumor activity of MDF.

Synergistic antiproliferative effect of delta 12-prostaglandin J2 (delta 12-PGJ2) and hyperthermia on human esophageal cancer cell lines.

delta 12-PGJ2, one of the cyclopentenone prostaglandins and the ultimate metabolite of prostaglandin D2, has been reported to have potent antiproliferative activity on various tumor cells in vitro and in vivo. In this study, the combined effect of delta 12-PGJ2 and hyperthermia on six established cell lines of human esophageal carcinoma (SGF series) was analyzed by an in vitro assay, and the degree of apoptosis induced by this combination was examined to clarify the mechanism of supra-additive effects. In five SGF cell lines, except SGF-7 cells, combination therapy with delta 12-PGJ2 and hyperthermia showed synergistic antiproliferative effects. The supra-additive combined effect of delta 12-PGJ2 and hyperthermia on esophageal cancer cells is attributed to the synergistic induction of apoptosis. delta 12-PGJ2 induced G1 accumulation and apoptosis was induced by delta 12-PGJ2 from G1 phase. Hyperthermia induced G1 accumulation and apoptosis was induced by hyperthermia during all cell phases. Both augmented G1 arrest followed by G1 phase-selective induction of apoptosis and increased apoptotic induction without cell-cycle specificity are responsible for the synergism of combined treatment with delta 12-PGJ2 and hyperthermia.

The combined effect against colon-26 cells of heat treatment and immunization with heat treated colon-26 tumour cell extract.

Cancer vaccines represent a promising new strategy for immunotherapy against cancer, but their effects are insufficiently understood. The effect of heat treatment against mouse colon adenocarcinoma cell line (colon-26), and combined effects of heat treatment and immunizing host animals with heat treated colon-26 cell extracts were investigated. Heat treatment of colon-26 cells induced heat-shock protein 70 (HSP70), but not other HSP. Immunization of BALB/cJ mice with heat treated colon-26 cell extract, which was enriched in HSP70, elicited antitumour immunity against subcutaneously injected colon-26 cells. Furthermore, combination therapy of heat treatment and immunization with heat treated colon-26 cell extract significantly reduced tumour volumes compared with heat treatment alone. Similar immunization enhanced the cytotoxic activity of mouse splenic lymphocytes against untreated and heat treated colon-26 cells in an in vitro assay, as well as against heat treated allogenic mouse lymphoma cell line (YAC-1). These findings suggest possible usefulness of heat treated cancer cell extract as a cancer vaccine, especially if given in combination with hyperthermia.

Tumor regression by inductive hyperthermia combined with hepatic embolization using dextran magnetite-incorporated microspheres in rats.

We formulated a novel preparation of microspheres incorporating dextran magnetite complex (DM-MS), which enable magnetic field-induced heating for the induction of hyperthermia. Using a 500 kHz magnetic field combined with arteriolar embolization of DM-MS, inductive hyperthermia was performed for the treatment of liver tumors in rats. Three days after treatment, the percentage increase of tumor volume in the embolo-hyperthermia, embolization alone, and control groups were 28%, 124%, and 385%, respectively, with the embolo-hyperthermia group differing significantly from the remaining groups. This study demonstrated the feasibility of combining embolization of DM-MS with hyperthermia as an antitumor therapy.

Active-oxygen scavenging activity of traditional nourishing-tonic herbal medicines and active constituents of Rhodiola sacra.

The active-oxygen scavenging activity of 70 traditional herbal medicines used in China and Japan as nourishing tonics were evaluated by electron spin resonance (ESR) technique, in order to evaluate their effectiveness for anti-aging and to search for new active-oxygen scavengers from natural resources. Most of the 70 herbal medicines showed scavenging activity with various intensities. Areca catechu (methanol extract), Dendrobium plicatile (methanol extract), Juglans regia (water extract), Paeonia lactiflora (methanol extract), Psychotria serpens (water and methanol extracts), Rhodiola sacra (water and methanol extracts) and Uncaria rhynchophylla (water extract) especially showed strong scavenging activity against superoxide anion radical (*O2-), while J. regia (water and methanol extracts), Morus alba (water extract) and Schisandra chinensis (water extract) revealed strong scavenging activity against hydroxyl radical (HO*). In addition, the active-oxygen scavenging activities of 19 compounds isolated from R. sacra were also examined, and hydroquinone (1), caffeic acid (3), protocatechuic acid (6), gallic acid (7), (-)-epigallocatechin 3-O-gallate (8), 3-O-galloylepigallocatechin-(4beta-->8)-epigallocatechin+ ++ 3-O-gallate (10), heterodendrin (17) and gallic acid 4-O-beta-D-glucopyranoside (19) were found to show mild or strong inhibitory activity against superoxide anion radical (*O2-), while 4-hydroxybenzoic acid (2), 3, 4-hydroxycinnamic acid (4), 6-8 and 19 inhibited hydroxyl radical (OH*). These active-oxygen scavengers may contribute, to different extents, to their anti-aging action.

[Dietary fiber inhibits the incidence of hepatic metastasis with the anti-oxidant activity and portal scavenging functions].

Dietary fiber is described as the proportion of plant foods not digested in the human small intestine. Among the various kinds of pectin, apple pectin exerts a bacteriostatic action and therefore may change the composition of the intestinal flora. The diet supplemented with 20% apple pectin significantly decreased the number and the incidence of AOM-induced colon tumors in rats. The prostaglandin E2 (PGE2) level in the distal colonic mucosa and blood of portal vein was lower in rats fed 20% pectin than those fed the basal diet. The ability of apple pectin to decrease PGE2 was dose-dependent and those results suggest an anti-inflammatory effect in the bowel. Rats fed apple pectin showed a significantly lower incidence of hepatic metastasis than those fed the basal diet. To determine whether the anti-inflammatory effect of Lactobacillus on hepatic metastasis model same as apple pectin, Lactobacillus casei was selected. Metastatic nodules were significantly reduced, especially in the group receiving pretreatment. Apple pectic oligosaccharides with small molecular weights showed highly inhibitory effects on hypoxanthin-xanthin oxidase and ferrous sulfate-hydrogen peroxide. The scavenging activity of apple pectic oligosaccharides was suitable and accelerated at high temperatures (120 degrees C, 30 min.). Apple pectin and Lactobacillus have a scavenger effect in the intestinal digestion and portal circulation system as an anti-inflammatory food and have very important function for the prevention of hepatic metastasis.

Clinical results of treatment of advanced esophageal carcinoma with hyperthermia in combination with chemoradiotherapy.

Chemoradiotherapy combined with hyperthermia was administered to 35 patients with advanced esophageal carcinoma who either required preoperative treatment or had nonresectable disease. As a rule, each patient received a total dose of 30 Gy in 15 daily fractions of 2 Gy, 5 d/wk. Bleomycin or cisplatin, in combination with fluorouracil, was employed as chemotherapy. Hyperthermia was applied by intraluminal heating twice a week for a total of six sessions using an apparatus (IH-500T; Japan Crescent Co Ltd; Tokyo, Japan) (radiofrequency, 13.56 MHz) with an intraesophageal applicator and two extracorporeal applicators placed on the chest and back. This treatment method obtained a response rate of 80%, consisting of a complete response rate of 22.9% and partial response of 57.1%. In 15 cases, the tumor became resectable (resectability rate, 42.9%) following treatment. The histologic study of the resected specimens revealed absence of viable tumor cells in five patients (33.3% of the resected cases) (markedly effective), and in six patients (40.0%), the combined therapy was considered to be moderately effective. No complications considered due to hyperthermia itself were recognized. The overall 5-year survival rate was 11.8%. In conclusion, chemoradiotherapy combined with hyperthermia was locally effective, yielding an overall response of 80.0%. However, the prognosis of the patients remains unfavorable. Advanced esophageal carcinoma requires treatment taking into account lymphatic and hematogenic metastasis at the beginning of treatment.

Anticarcinogenic action of apple pectin on fecal enzyme activities and mucosal or portal prostaglandin E2 levels in experimental rat colon carcinogenesis.

Pectin is a partially methoxylated polymer of galacturonic acid obtained from fruits. Among pectin, apple pectin exerts stronger bacteriostatical action on Staphylococcus aureus, Streptococcus faecalis, Pseudomonas aeruginosa and Escherichia coli in comparison with citrus pectin. In this study, we used water-soluble methoxylated pectin from apple. The diet, supplemented by 20% apple pectin, significantly decreased the number of tumors and the incidence of colon tumor. PGE2 level in distal colonic mucosa in 20% apple pectin fed rats were lower than those in basal diet fed rats. Fecal beta-glucuronidase activities in the apple pectin fed group, which has been considered a key enzyme for the final activation of Dimethylhydrazine metabolism to carcinogens in the colonic lumen, were signifieantly lower than those in control group at initiation stage of carcinogenesis. In the case the concentrations of beta-glueosidase and azoreductase were also decreased. The effect of apple pectin on the colon carcinogenesis may partially depend on PGE, concentration decrease in colonic mucosa and on the type of pectin, also related to fecal enzyme activities.

Inhibitory effect of a traditional Chinese medicine, Juzen-taiho-to, on progressive growth of weakly malignant clone cells derived from murine fibrosarcoma.

We have investigated the inhibitory effect of oral administration of Juzen-taiho-to, a Kampo (Chinese herbal) medicine, on progressive growth of a mouse fibrosarcoma. Spontaneously regressive QR-32 tumor cells were able to grow progressively in vivo when coimplanted s.c. with a foreign body, gelatin sponge, whereas QR-32 cells alone gradually grew for over 15 days after inoculation and thereafter regressed for up to 25 days. Oral administration of Juzen-taiho-to (40 mg/day/mouse) for 7 days after inoculation of QR-32 cells with gelatin sponge resulted in significant inhibition of tumor growth and prolongation of the survival of the tumor-bearing mice. This growth-inhibitory effect of Juzen-taiho-to observed on day 25 was dose-dependent over the dose range from 4 to 40 mg/day. Treatment with Juzen-taiho-to for 7 days before tumor inoculation with gelatin sponge also significantly suppressed tumor growth examined on day 25, as did the administration of bismuth subnitrate, which is well known to induce metallothionein, an antioxidant. On the other hand, inoculation of progressed tumor cells (QRsP) resulted in growth without gelatin sponge, leading to death in syngeneic mice. Administration of Juzen-taiho-to for 7 days after inoculation of QRsP cells resulted in a decrease of the tumor growth and prolongation of the survival of mice, but the effect was less than that on the growth of QR-32 regressor tumor after coimplantation with gelatin sponge. These results suggest that the inhibitory effect of Juzen-taiho-to is partly associated with prevention of gelatin sponge-elicited progressive growth, probably mediated by endogenous factors including antioxidant substances, in addition to the augmentation of host-mediated antitumor activity.

Possibility of thermosensitive magnetoliposomes as a new agent for electromagnetic induced hyperthermia.

This study examined a possibility of dextran magnetite (DM)-incorporated thermosensitive liposomes, namely thermosensitive magnetoliposomes (TMs), as a new hyperthermic agent. The temperatures of TM suspensions and cancer tumors injected with TM suspensions were efficiently elevated up to 42 degrees C by electromagnetic induced heating at a frequency of 500 kHz under both in vitro and in vivo conditions. Thus, a possibility of TMs for selective hyperthermia was demonstrated. The temperature rises obtained at various concentrations of TMs suggest that approximately 15 mg Fe/cm3 tumor volume is adequate as a therapeutic dose of TMs for efficient selective hyperthermia.

Preparation and characterization of dextran magnetite-incorporated thermosensitive liposomes: an on-line flow system for quantifying magnetic responsiveness.

PURPOSE: Dextran magnetite (DM)-incorporated thermosensitive liposomes, namely thermosensitive magnetoliposomes (TMs), were prepared and characterized in order to investigate their possibility for magnetic drug targeting. METHODS: TMs containing calcein were prepared at various DM concentrations by reverse-phase evaporation of dipalmitoylphosphatidylcholine (DPPC). They were evaluated for their physicochemical properties including size, DM capture, magnetite distribution within liposomes, and temperature-dependent calcein release. Moreover, a novel on-line flow apparatus with a sample injector, a coil of tubing placed in an electromagnet, and a fluorescence detector was developed for quantifying the magnetic responsiveness of TMs. This device allowed us a real-time measurement of percentage holding of TMs by magnetic field. RESULTS: Due to water-soluble property of DM, higher contents of magnetite up to 490 mg per mmol DPPC were successfully incorporated into the liposomes with DM than with conventional magnetite (Fe3O4). Thermosensitivity and lipid integrity of TMs were not influenced by inclusion of DM. Using the on-line flow system, percentage holding of TMs by magnetic field was shown to vary with several factors; it increases as the magnetic field strength increases, the fluid flow rate decreases, the magnetite content increases, and the liposome concentration increases. Typically, at 490 mg incorporated magnetite per mmol DPPC, 0.5 ml/min-fluid flow rate, and high magnetic field strength (> or = 10 kiloGauss), approximately 100% of TMs were found to be held. CONCLUSIONS: The TMs were suggested to be useful in future cancer treatment by magnetic targeting combined with drug release in response to hyperthermia.

Effects of apple pectin on fecal bacterial enzymes in azoxymethane-induced rat colon carcinogenesis.

Because of the potential significance of colonic bacteria in colon carcinogenesis, we investigated the effect of pectin of different types on fecal bacterial enzymes (beta-glucuronidase, beta-glucosidase and tryptophanase) at various periods of time after feeding rats with pectin-containing diets during azoxymethane-induced colon carcinogenesis. The diet supplemented with 20% apple pectin or 20% citrus pectin decreased the multiplicity of colon tumors, and the number of tumors was significantly decreased in the group fed apple pectin. The incidence of colon tumors in the apple pectin group was lower than that in the control group. The mean tumor size was similar among the three groups. Apple pectin feeding decreased fecal beta-glucosidase and tryptophanase levels. Furthermore, a significant decrease in the activity of beta-glucuronidase was observed in the apple pectin group during the initiation phase. These findings suggest that the protective effect of pectin on colon carcinogenesis may be dependent on the type of pectin and be related to the decrease of beta-glucuronidase activity in the initiation stage of carcinogenesis.

[Successful treatment of advanced gastric cancer (Borrmann 1 type) with FTP chemotherapy after reduction surgery].

A 54-year-old man was diagnosed with Borr 1 type gastric cancer, located just below ECJ with some paraaortic lymph node metastase, during treatment of diabetes mellitus at another hospital. He underwent spleno-total gastrectomy for reduction. The metastatic lymph nodes of the para-aorta were not resected, so the surgery was considered palliative. We administered FTP chemotherapy (CDDP 110 mg/day 1, 5-FU 1,200 mg/day 1-5, THP-ADM 30 mg/day 1) 5 times following surgery. The metastatic lymph nodes were remarkably decreased in size by the initial treatment. The decrement was 52.4% after the initial treatment (PR). After the 4th treatment, there were no lymph nodes detected (CR). After the 5th treatment, CR continued. The PR period was considered to be 5 months, and that of CR 4 months. The patient has no renal or heart dysfunction, and no suppression of bone marrow. His quality of life is satisfactory, and he continues to work as prior to surgery. FTP chemotherapy is considered a successful regimen for postoperative chemotherapy.

[Clinicopathological evaluation of high-range hyperthermia for advanced thoracic esophageal carcinoma].

The effectiveness of high-range hyperthermia over 45 degrees C for advanced esophageal carcinoma was clinicopathologically evaluated. Fifty-eight patients with advanced thoracic esophageal carcinoma were treated with radio-chemotherapy. They were divided into two groups: group I included 32 cases, all of whom received hyperthermia (13 cases: high-range hyperthermia); group II included the other 26 cases. The patients were given 2 Gy/day for a total of 15 sessions in 3 weeks. Bleomycin and cisplatin in combination with 5-fluorouracil have been employed as chemotherapy. Hyperthermia was performed twice a week for a total of 6 sessions. Intraluminal heating was done using Japan Crescent Inc. IH-500 T (RF, 13.56 MHz), with an intraesophageal applicator and two extra-corporeal applicators on the chest and the back. Concerning local effects, the efficacy rate was 81.3% in group I (high-range: 92.9%), and 42.3% in group II. The histologic effectiveness, when Grade 2 and 3 are determined as histologically effective, were 64.3% (high range: 85.7%) and 50.0% in group I and II, respectively.

[Hyperthermia for cancer with dextran magnetite using tubular implants].

Dextran magnetite particles (Meito Sangyo Corp.) are an aqueous magnetite zol and a nanometer complex consisting of dextran chains surrounding a core of ultrafine iron oxide. The tubular implants were made with polyester tube (3 mm diameter, 20 mm length) filled with DM aqueous zol (29%w/v). The temperature of an agar phantom with implants was measured in the inductive field. Heating was effected by creating an electromagnetic field with a 7 kW generator operating at 500kHz (Yamamoto Vinyter). The temperature was elevated 3.4 degrees at a distance of 5 mm from the implant at an inductive power of 2.6 kW. An area of 20 x 20 mm was heated while changing the power, the number of implants, and their arrangement. Selective heating of cancer was considered possible by inductive heating at 500 kHz and DM implants. Since the DM aqueous zol configuration can be readily changed, treatment of various cancers is possible.

The clinical pharmacokinetics of two different preparations of intrarectal ketoprofen following spinal or local anesthesia for anal surgery.

Two different preparations of commercially available suppositories containing Ketoprofen (KP) were administered to 49 patients immediately following anal surgery. The KP was prepared as either fatty suppositories (FS) or gelatin capsulated suppositories (GCS) and surgery was performed under either spinal (n = 37) or local anesthesia (n = 12). Similar results were observed in the kinetics of KP after both FS and GCS administration. The extent of bioavailability of the two dosage forms in the patient groups and control subjects (n = 10) were essentially equal. When the pharmacokinetic parameters of KP were compared between patient groups under spinal and local anesthesia, significant differences were found in the values of the peak level (C max), peak time (T max), and terminal phase half-life (t 1/2). The C max decreased by one-half, while the T max and t 1/2 increased twice and four times, respectively, in patient operated on under spinal anesthesia compared to those operated on under local anesthesia. The absorption rate constant (Ka) following spinal anesthesia was significantly less than that following local anesthesia or that of the healthy subjects (p less than 0.01). A "flip-flop" phenomena could be seen in the time profiles of plasma KP concentration following spinal anesthesia.

[Interstitial hyperthermia (MINERVE) for perineal local recurrence of rectal cancer].

Interstitial hyperthermia (MINERVE) was performed for 2 patients with perineal local recurrence of rectal cancer. The MINERVE was a 20 W generator of 550-610 kHz with 4 pairs of probes creating an electromagnetic field (Odam Co., France). The basic regimen was five irradiation treatments of 2 Gy per week, with two hyperthermia treatments (for 60 minutes at more than 43.5 degrees C) a week, 500 mg of 5-FU or 25 mg of CDDP per hyperthermia treatment, and 3 g/day of PSK. The radiation therapy was performed prior to hyperthermia, the chemotherapy at the same time. Perineal tumors and symptoms disappeared completely in 1 patient and were reduced in 1 patient. This treatment is expected to be clinically as a part of multidisciplinary treatment for superficial malignant tumors.