Studies of the induction and maintenance of long-term graft acceptance by treatment with FK506 in heterotopic cardiac allotransplantation in rats

Immunosuppressive activities of the newly discovered FK506, isolated from Streptomyces tsukubaensis, were examined by using cardiac allotransplantation in the rat, and the mechanisms underlying induction and maintenance of FK506-induced long-term allograft survival were studied. Male rats of WKA (RT1k) and F344 (RT1lvl) strains were used as recipients and donors, respectively, and those of BN (RT1n) strain were used as third-party donors. Treatment with FK506, beginning from the day of allografting for 14, 10, or as few as 4 days, prolonged allograft survival significantly across the major histocompatibility barrier. The minimum doses for prolonging graft survival were 0.1 mg/kg/day by intramuscular treatment and 1.0 mg/kg/day by oral treatment. Treatment with FK506 at a dose of 0.32 mg/kg/day from day 4 until day 10 resulted in all the grafts surviving indefinitely and from days 5 to 10, half the grafts survived indefinitely, suggesting that the agent inhibited ongoing rejection. On the other hand, cyclosporine treatment at a dose of 20 mg/kg/day from day 2 did not prolong graft survival time statistically significantly. Induction of prolonged graft survival was not obtained by pretreatment of the prospective donor or recipient; prolonging effects were observed only when the agent was administered after allografting. Thus, the primary effect of the agent is exerted on responder lymphocytes reacting to the donor antigens in the induction phase of long-term graft acceptance. The mechanisms underlying the maintenance of long-term grafts were analyzed by testing the capacity of lymphocytes or serum of long-term graft-bearing rats to inhibit graft rejection in irradiated grafted hosts. Transfer of 2 x 10(8) lymphocytes from FK506-induced long-term F344 graft-bearing WKA rats resulted in indefinite survival of F344 heart allografts, but it did not prolong survival of third-party BN hearts. Transfer of 2.5 ml serum from long-term graft-bearing rats also prolonged graft survival of F344 hearts, but not BN hearts. These results suggest that donor strain-specific suppressor cells and humoral factor(s) are induced by treatment with FK506 in the presence of allografts, and that they play at least partial roles in the maintenance of long-term allograft acceptance.     

Increased ratio of saturated to unsaturated C18 fatty acids in colonic adenocarcinoma: Implications for cryotherapy and lipid raft function

Mammalian fatty acid synthase (FASE) overexpression has been shown in a number of human malignancies including colonic adenocarcinoma. Since FASE synthesizes only saturated fatty acids, we hypothesized that cancer cells have a greater proportion of long-chain saturated fatty acids. We studied and found an unequivocal increase in saturated C18 fatty acid (stearic acid) in colonic adenocarcinoma compared to adjacent normal colonic mucosa. The increase is even more striking when measured as a ratio of stearic acid to the unsaturated C18 fatty acids (oleic acid and linoleic acid). This change in fatty acid composition of the cancer cells should significantly alter their physical and biological properties. The increase in relative proportion of saturated fatty acids should make the cancer cells more susceptible to cryodamage and measurement of fatty acid composition of cancer cells may help individualize the temperature for cryotherapy. Also, the lipid alterations may affect the structure and functions of lipid rafts, which may enable the cancer cells to affect signaling mechanisms such as those involved in cell growth and apoptosis. Dietary or therapeutic interventions targeting lipid rafts may thus be an option for cancer treatment.     

Reduction of Nitric Oxide with L–/Vc–Monomethyl Arginine in lnterleukin–2 and Anti–CD3 Monoclonal Antibody Combination Therapy

We evaluated nitric oxide induction in antitumor therapy consisting of anti–CD3 monoclonal antibody (anti–CD3) and interleukin–2 (IL–2), then determined the effect of nitric oxide reduction with L–N^G–monomethyl arginine (LNMA) on the therapeutic methods. Female C57BL/6 mice, MCA102 (a non immunogenic, NK–resistant murine fibrosarcoma cell line), and 145–2C11 (hamster anti–murine–CD3 mAb) were utilized in an experimental hepatic metastasis model developed by injecting a tumor cell suspension into the spleen of mice. A marked increase in serum NO₂^–+ NO₁ was observed at 19 hours after anti–CD3 (10 μ, IV) and additional IL–2 administrations (40times10¹ U, twice, If) induced a further increase. The NO₂, + NO_3- elevation in spot urine in the combination therapy was not suppressed with LNMA at a dose of 100 μg/h but was significantly lowered at 300 μg/h. The efficacy of the anti–CD3 + IL–2 therapy was not diminished by LNMA administration either at 100 μg/h or at 300 μg/h.     

Organ specific ESR features in mouse main organs and ESR application to the model of pancreatic disorders

Nine main organs in the mouse were studied by ESR spectroscopy at 77K. Manganese ions were readily detected in the pancreas, small intestine, stomach and kidney. In particular, the pancreas gave strong ESR signals for the transition metal, suggesting that Mn(II) plays an important role in pancreatic function. All organs reveal different ESR spectra indicating organ specificity. C-centered radical, R-OO radical and C0Q10 or ascorbate radical are stable in the tissue. In the brain, heart and pancreas, N-centered radical heme-NO adduct was detected at 6 and 24 h after excision since common process is involved in tissue degeneration and ESR is sensitive to proteolysis and necrosis of tissues. In endotoxemia and/or CDE-diet-induced pancreatic lesions, R-OO radical and Mn(II) ion were detected in the signal at 77K. By the spin-trapping method (DMPO) at 25 degrees C, DMPO-OH adduct and 3-Line and 6-Line were detected in CDE diet-induced acute pancreatitis. These results suggest that damaged pancreatic tissues are in a highly oxidative environment that probably contains oxygen radicals, and that free radicals are considered to play an important role in the development of pancreatic lesions.     

Early rapid weight gain and current overweight in relation to asthma in adolescents born with very low birth weight

Early catch-up growth and subsequent overweight are suggested to be associated with later cardiovascular diseases and later type II diabetes. However, the impact of early catch-up growth and childhood overweight on the development of asthma has been less studied, particularly in children born with very low birth weight (VLBW). A birth cohort of 74 VLBW children (birth weight < or = 1500 g) was followed from birth and investigated on asthma at 12 yr of age. Early rapid weight gain was in one way defined as an increase of weight > or =1 standard deviation score (SDS) at 6 months of corrected postnatal age. Current overweight was defined by body mass index (BMI) exceeding 21.2 and 21.7 kg/m(2), respectively, for boys and girls at 12 yr of age. Current asthma was diagnosed by a pediatrician, according to asthma ever in combination with a positive response to hypertonic saline bronchial provocation test and/or wheeze at physical examination at 12 yr old. Being overweight at 12 yr of age was associated with an increased risk for current asthma in the VLBW children [crude odds ratio (OR): 5.5, 95% confidence interval (CI): 1.3-22.2]. After adjustment for early weight gain and neonatal risk, the OR of overweight increased nearly three times (adjusted OR: 15.3, 95% CI: 2.5-90.6). Early rapid weight gain seemed to be inversely associated with current asthma (adjusted OR: 0.49 for an increase of weight equal to 1 SDS, 95% CI: 0.23-1.02, p = 0.06). In addition, early rapid weight gain was inversely associated with the magnitude of bronchial responsiveness at 12 yr (coefficient -1.15, p < 0.01). There was a strong and positive association between overweight and asthma at 12 yr of age in the VLBW children. This strong association had been reduced by early rapid weight gain, possibly via the reduction of bronchial responsiveness.     

A case of Cushing's syndrome caused by an adrenal black adenoma

A black adenoma of the adrenal cortex was surgically removed from an 18-year-old female who had clinical and laboratory findings characteristic of Cushing's syndrome. The electron microscopic study revealed typical features of steroid-producing cells, including a prominent smooth and rough endoplasmic reticulum, and mitochondria. In addition, many of the adenoma cells contained numerous pigmented granules which were lipofuscin. Three months after the surgery, the hormone levels returned to the normal range. The Japanese literature of functional black adenoma is reviewed.     

Stimulation of monocyte iodination and IL-1 production by tannins and related compounds.

Various tannins and related compounds were compared for their ability to stimulate the iodination (incorporation of radioactive iodine into an acid-insoluble fraction) of human peripheral blood monocytes. The stimulating activity of most of the monomeric and dimeric hydrolyzable tannins was generally higher than that of the trimeric and tetrameric compounds. Compounds that had dehydrohexahydroxydiphenoyl or chebuloyl groups had considerably less activity than those that had other functional groups (hexahydroxydiphenoyl, valoneoyl, dehydrodigalloyl, isodehydrodigalloyl, lactonized valoneoyl, hellinoyl, euphorbinoyl, dehydroeuphorbinoyl or woodfordinoyl group). The methylated derivative, nonacosa-O-methylcoriariin A, was essentially inactive, suggesting the requirement of a phenolic hydroxyl group. Three condensed tannins ((-)-epicatechin 3-O-gallate (ECG)-dimer, ECG-trimer and ECG-tetramer) significantly stimulated both monocyte iodination and their interleukin-1-like factor production. The results suggest the dependence of stimulation of monocyte iodination by tannins and related polyphenols on molecular weight.     

Antiulcer effects of 3-[[[2-(3,4-dimethoxyphenyl)ethyl] carbamoyl]methyl]-amino-N-methylbenzamide in experimental gastric and duodenal ulcers

Effects of 3-[[[2-(3,4-dimethoxyphenyl)ethyl]carbamoyl] methyl]-amino-N-methylbenzamide (DQ-2511), a newly synthesized compound, were evaluated using various types of experimental gastric and duodenal ulcers in rats. Pretreatment with DQ-2511, over the dose range 30-300 mg/kg p.o., resulted in a dose-related inhibition of water-immersion stress-, serotonin-, acetylsalicylic acid (ASA)-, indometacin-, ethanol-, and 2-deoxy-D-glucose(2DG) plus indometacin-induced gastric ulcers as well as cysteamine-induced duodenal ulcers. The antiulcer potencies of DQ-2511 were equal to or greater than those of H2-receptor antagonist cimetidine in these ulcer models except for ASA- and 2DG plus indometacin-induced ulcers. The rate of healing of chronic gastric ulcers induced by acetic acid was significantly accelerated by DQ-2511 (100 and 300 mg/kg p.o.) but not by the same doses of cimetidine. DQ-2511, at doses of 30 mg/kg p.o. and above, produced a significant decrease in gastric acid and pepsin output in pylorus-ligated rats. In anesthetized rats with acute gastric fistulae, 30 mg/kg i.v. of DQ-2511 significantly inhibited gastric acid secretion stimulated by 2DG, whereas it did not affect gastric hyperacidity evoked by either carbachol, histamine or pentagastrin. At effective antiulcer doses, this compound produced a sustained increase in gastric mucosal blood flow in conscious, restrained rats. Based on these observations, DQ-2511 is characterized as a new antiulcer compound with beneficial effects on both gastric aggressive and defensive factors. Furthermore, these results indicate a possible superiority of DQ2511 over cimetidine in regard to its antiulcer potency and spectrum.     

Absorption of tetrahydropyranyl adriamycin administered intravesically immediately after transurethral resection of bladder carcinoma

Absorption of tetrahydropyranyl adriamycin (THP) administered immediately after transurethral resection of bladder carcinoma (TUR-Bt) has not been reported. In this study, we have examined the absorption of THP and the systemic toxicity in the early post-TUR period. Of 21 patients with bladder carcinoma, 10 had a solitary tumor and 11 multiple tumors. Twenty mg THP in 40 ml of sterile water was intravesically administered on days 1, 3, 5, 7, 14 and 28, and then every 4th week. The THP solution was retained for 2 hours. The blood THP concentration was measured 30 minutes and 2 hours after the intravesical administration on days 1, 7 and 28. No systemic side effects were observed. Thirteen of the 38 (34%) samples contained a detectable level (more than 1 ng/ml) of THP on the post-TUR-Bt on day 1, 8, of 42 (19%) on day 7, and 3 of 18 (17%) on day 28. Altogether, 24 of the 98 (24%) samples contained more than 1 ng/ml THP. The highest blood THP level was 23 ng/ml on day 1. The differences between frequency of detection of blood THP in the samples at 30 minutes and 2 hours were not statistically significant. The difference between average concentration of blood THP of patients with solitary and multiple tumors also was not significant. These results indicate that intravesical THP administration starting within 24 hours after TUR-Bt can not result in significant systemic absorption of THP, and the systemic toxicity can be avoided.     

Decreased responsiveness to beta-adrenoceptor agonists in arterial strips from spontaneously hypertensive rats is not associated with alterations in beta-adrenoceptors.

Beta-adrenoceptors in femoral and mesenteric arteries from 13-week-old spontaneously hypertensive rats (SHR) and normotensive Wistar-Kyoto (WKY) rats were studied using radioligand binding assays and were compared with in vitro measurements of beta-adrenoceptor-mediated relaxation. The relaxant responses to noradrenaline via beta-adrenoceptors were significantly decreased in the SHR femoral artery when compared with the WKY femoral artery. However, under the same conditions, arterial relaxant responses to forskolin, an activator of adenylate cyclase, were not significantly different between SHR and WKY rats. Specific binding of 125I-iodocyanopindolol to membranes prepared from femoral arteries of SHR and WKY rats was saturable and of high affinity. Neither the equilibrium dissociation constant of 125I-iodocyanopindolol, nor the maximum number of binding sites were significantly different between SHR and WKY rats. Similar results were obtained in the case of mesenteric arteries from SHR and WKY rats. These results indicate that the decreased responsiveness to beta-adrenoceptor stimulation in SHR arteries is not associated with alterations in beta-adrenoceptors and further support the hypothesis that a reduced function of the stimulatory guanosine triphosphate-binding protein is responsible for the decreased responsiveness to a variety of receptor agonists whose mechanism of action involves adenylate cyclase activation.