Antitumor Immunity Induction by Intracellular Hyperthermia Using Magnetite Cationic Liposomes

Induction of antitumor immunity to T-9 rat glioma by intracellular hyperthermia using functional magnetic particles was investigated. Magnetite cationic liposomes (MCLs), which have a positive surface charge, were used as heating mediators for intracellular hyperthermia. Solid T-9 glioma tissues were formed subcutaneously on both femurs of female F344 rats, and MCLs were injected via a needle only into the left solid tumors (treatment side). The rats were then divided into two groups, which received no irradiation, or irradiation for 30 min given three times at 24-h intervals with an alternating magnetic field (118 kHz, 384 Oe). On the treatment side, the tumor tissue disappeared completely in many rats exposed to the magnetic field. The tumor tissue on the opposite side also disappeared completely, even though MCLs were not injected into the right solid tumors. To examine whether a long-lasting and tumor-specific immunity could be generated, the rats that had been cured by the hyperthermia treatment were rechallenged with T-9 cells 3 months later. After a period of transient growth, all tumors disappeared. Furthermore, immuno-cytochemical assay revealed that the immune response induced by the hyperthermia treatment was mediated by both CD8⁺ and CD4⁺ T cells and accompanied by a marked augmentation of tumor-selective cytotoxic T lymphocyte activity. These results suggest that our magnetic particles are potentially effective tools for hyperthermic treatment of solid tumors, because in addition to killing of the tumor cells by heat, a host immune response is induced.     

Body fat accumulation is greater in rats fed a beef tallow diet than in rats fed a safflower or soybean oil diet

The effects of dietary fats , consisting of different fatty acids, on body fat accumulation and uncoupling protein (UCP) in interscapular brown adipose tissue were studied in rats. Metabolisable energy in experimental diets based on safflower oil, soybean oil or beef tallow was measured strictly (experiment 1). Male Wistar rats were then meal-fed an isoenergetic diet for 8 weeks (experiment 2). Each group of rats showed the same weight gain during the 8-week experimental period. Carcass fat content was greater in rats fed the beef tallow diet than in those fed the with the safflower or soybean oil diets, whereas the weight of abdominal adipose tissue was the same for all three dietary groups. Gene expression of UCP1 and the UCP content of the interscapular brown adipose tissue was lower in the beef tallow diet group than in the other dietary groups. A negative correlation was observed between carcass fat content and n-6 unsaturated fatty acid content in dietary fats. These results suggest that the greater body fat accumulation in rats fed the beef tallow diet results from lower expression of UCP1 mRNA and lower UCP content in brown adipose tissue. n-6 Polyunsaturated fatty acids may be the most effective fatty acids in limiting body fat.     

Effects of light resistance exercise using dumbbells and rubber band with mild energy restriction on body composition and physical fitness in obese Korean women

The effects of light resistance exercise using dumbbells and rubber band with mild energy restriction on body composition and physical fitness were studied in 11 mildly obese Korean women aged 38-59 years. The subjects performed dumbbell exercises with pairs of 0.5-1 kg dumbbells and rubber band exercise 3 days per week for approximately 40 min. Subjects were restricted to approximately 80% of energy intake RDA for Korean women for 12 weeks. Subjects were measured for body composition, physical fitness, and blood and serum biochemical data before commencing the experiment and again at 12 weeks while still dieting. During the 12-week experimental period, body weight and body fat decreased significantly without reducing fat free mass. Grip and back strength increased significantly during the experimental period. These results suggest that combination of dumbbell and rubber band exercises decreases body weight and body fat without reducing FFM while increasing physical fitness.     

Novel models for human scirrhous gastric carcinoma in vivo

Human scirrhous gastric carcinoma, a diffusely infiltrating type of poorly differentiated gastric carcinoma also known as linitis plastica type carcinoma, is characterized by cancer cell infiltration and proliferation accompanied with extensive stromal fibrosis. We established two new gastric cancer cell lines, designated OUCM-8 and OCUM-11, which developed the characteristic biology of scirrhous gastric carcinoma upon orthotopic implantation in mice. Involvement of lymph nodes and liver metastasis was also found in both orthotopic models. Histologically, these orthotopic models showed proliferation with extensive fibrosis, resembling human scirrhous gastric cancer. Both cell lines were derived from ascites of patients with scirrhous gastric cancer. The growth of OCUM-8 and OCUM-11 cells following the addition of KGF, FGF, and EGF was increased significantly relative to untreated cells. An increase in the number of attached and spreading cells occurred following the addition of TGF-beta 1 in both cell lines. OCUM-11 cells showed microsatellite instability. Although subcutaneous scirrhous gastric cancer cells show medullary growth, most in vivo studies of scirrhous gastric cancer have used xenografted tumors implanted subcutaneously. Only in a few cases was it confirmed that these scirrhous gastric cancer cell lines retained the original histologic characteristics. Our orthotopic models should contribute to the elucidation of disease progression in situ and to the development of therapy for scirrhous gastric cancer.     

Transganglionic gracile response following limb amputation in man

Gracile neuroaxonal dystrophy (NAD) is an distinctive morphological alteration of central projecting axon terminals of dorsal root ganglion neurons. Experimentally, lower limb amputation has been shown to accelerate the formation of gracile NAD, suggesting that the transganglionic response to peripheral axotomy may play a role in its development. To determine if a similar response occurs in the human sensory nervous system following peripheral nerve injury, we have performed postmortem histopathological examinations of the dorsal column nuclei of three patients (aged 15, 55, and 77 years old); all of whom had undergone accidental or therapeutic unilateral limb amputation (1 year, 38 years, and 1 year 8 months prior to death, respectively). In a 15-year-old man who underwent therapeutic leg amputation, the gracile nuclei on the transected side revealed reactive gliosis and many small axonal spheroids. The spheroids and fine neurites were immunolabelled with antibodies for growth-associated protein-43, ubiquitin and neuropeptide Y (NPY). Neither routine histological nor immunohistochemical methods demonstrated comparable changes in the contralateral gracile nucleus. In a 77-year-old man who underwent leg amputation, the gracile nucleus on the amputated side was gliotic and showed several NPY and ubiquitin-immunoreactive spheroids, which were not seen in the contralateral non-transected side. A 55-year-old man with a history of accidental arm amputation showed well-developed NAD in the cuneate nucleus only on the transected side. This study clearly demonstrates the occurrence of transganglionic response to limb amputation in human dorsal column nuclei. The extent of the regenerative and/or degenerative responses may vary depending on the age of the patient and the time interval following the peripheral axotomy. Received: 26 November 1999 / Revised, accepted: 19 Januray 2000     

Combination chemotherapy of S-1/low-dose CDDP/lentinan for advanced gastric cancer

Eight patients with inoperable advanced gastric cancer were treated with combination chemotherapy of S-1, low-dose cisplatin(CDDP)and Lentinan. S-1 80 mg/ m2 was orally administered for 2 weeks followed by 1-week rest, CDDP 15 mg/ m2 and Lentinan 2 mg/body were given intravenously on day 1 and 8. One complete response and four partial responses were observed for an overall response rate of 63%(5 of 8 patients). Only one patient developed over grade 3 toxicity leukocytopenia. Many patients could be maintained by long-term continuous treatment. Since combination chemotherapy of S-1/low-dose CDDP/Lentinan for advanced gastric cancer was very tolerable, it could be used for a long time.     

Effect of Functional Magnetic Particles on Radiofrequency Capacitive Heating: An in vivo Study

Specific heating of magnetic particles in radiofrequency (RF) capacitive hyperthermia and its hyper-thermic effect were investigated in an in vivo study. Magnetite cationic liposomes (MCLs) were injected into a rat tumor on the femur and 8 MHz-RF capacitive heating was applied to the rat under'mild heating' conditions. Although the input power of RF capacitive heating was low under the same power conditions, the MCLs-injected tumor was heated over 43°C, whereas it was only heated to 41°C in the case of the rats not injected with MCLs. A necrotic area in the tumor was observed in the heated rats. From the results of histological observation of the removed tissue, the necrotic area in the MCLs-injected tumor was wider than that in MCLs-free tumor. Complete tumor suppression was observed in 71% (5/7) of MCLs-injected rats, and the hyperthermic effect was greatly improved by the MCLs.     

Comparison of open and closed methods for vitrification of human embryos and the elimination of potential contamination

Survival and development of human embryos was compared following slow cooling versus vitrification involving more than 13,000 vitrified embryos. In addition, the efficacy of an open system, the Cryotop, and a closed vitrification system, the CryoTip(trade mark), were compared using human blastocysts. One hundred percent of vitrified human pronuclear stage embryos survived and 52% developed to blastocysts as compared with 89% survival and 41% blastocyst development after slow cooling. Similar survival rates were seen with vitrification of 4-cell embryos (98%) as compared with slow cooling (91%). Furthermore, 90% of vitrified blastocysts survived and resulted in a 53% pregnancy rate following transfer, as compared with 84% survival and 51% pregnancy rates following slow cooling. All corresponding values were significantly different. When the closed and open vitrification systems were compared, no difference was found with regard to supporting blastocyst survival (93 and 97% for CryoTip and Cryotop respectively), pregnancies (51 versus 59% respectively) and deliveries (48 versus 51% respectively). Vitrification is a simple, efficient and cost-effective way to improve cumulative pregnancy rates per cycle. The use of the closed CryoTip system eliminates the potential for embryo contamination during cryopreservation and storage without compromising survival and developmental rates in vitro and in vivo.     

Effects of resistance exercise training on mass, strength, and turnover of bone in growing rats

To determine the effects of resistance exercise on mass, strength and local turnover of bone, 50 Sprague Dawley rats, 8 weeks of age, were assigned to five groups: a baseline control and two groups of sedentary and exercising rats. The trunk of the rats was kept upright during electrically stimulated jumping exercise for 1 h every other day. In 4 weeks, the trabecular mineralizing surface per bone surface (MS/BS), bone formation rate per bone surface (BFR/BS) and the compression load of the lumbar body increased and the number of osteoclasts decreased, but bone mineral density (BMD) and structure did not increase. In the mid femur, the cross-sectional area, the cortical bone area, the moment of inertia, the periosteal MS/BS, BFR/BS and the bending load increased in the exercise group. In 8 weeks, the increases in BMD, structure and load values were significant in both the lumbar and mid femur. At both 4 and 8 weeks, the MS/BS for the endocortical surface of mid femur were not increased and mineral apposition rate (MAR) remained reduced. These results show that jumping exercise increases the mass and strength of the lumbar vertebrae and mid femur by stimulating bone formation and accelerates cortical drift by both increasing periosteal bone formation and reducing the endocortical MAR. Accepted: 1 February 2000