Intake ratio of 131I to 137Cs derived from thyroid and whole-body doses to Fukushima residents

This study deals with the intake ratio of (131)I to (137)Cs that allows for the utilisation of late whole-body measurements to reconstruct the internal thyroid doses to Fukushima residents. The ratio was derived from the thyroid dose distribution of children and the effective dose distribution of adults based on the assumption that various age groups of persons inhaled the two nuclides at the same activity ratio and at around the same time, while taking into account age-dependent ventilation rates. The two dose distributions were obtained from residents of Iitate village and Kawamata town, located northwest of Fukushima Daiichi nuclear power plant (FDNPP). As a result, the intake ratios for the residents were 2-3, which was much smaller than the activity ratio observed in air sampling. A main reason for this discrepancy presumably lies in the relatively smaller thyroid uptake for iodine in the Japanese subjects than that in the reference persons on whom the biokinetic model promulgated by International Commission on Radiological Protection is based. The actual intake ratio of the two nuclides is believed to have been higher south of the FDNPP; however, this would depend on which of three significant plume events dominantly contributed to the intake for individuals. Further studies are needed to clarify this issue as a part of the reconstruction of early internal doses related to the FDNPP accident.

Estimating Annual Individual Doses for Evacuees Returning Home to Areas Affected by the Fukushima Nuclear Accident

To contribute to the reconstruction and revitalization of Fukushima Prefecture following the 2011 nuclear power disaster, annual individual doses were estimated for evacuees who will return home to Tamura City, Kawauchi Village, and Iitate Village in Fukushima. Ambient external dose rates and individual doses obtained with personal dosimeters were measured at many residential and occupational sites throughout the study areas to obtain fundamental data needed for the estimation. The measurement results indicated that the ratio of individual dose based on a personal dosimeter to the ambient external dose measurement was 0.7 with 10% uncertainty. Multiplying the ambient external dose by 0.7 may be an appropriate measure of the effective dose to an individual in the investigated area. Annual individual doses were estimated for representative lifestyles and occupations based on the ambient external dose rates at the measurement sites, taking into account the relationship between the ambient external dose and individual dose. The results were as follows: 0.6-2.3 mSv y in Tamura, 1.1-5.5 mSv y in Kawauchi, and 3.8-17 mSv y in Iitate. For all areas investigated, the estimated dose to outdoor workers was higher than that to indoor workers. Identifying ways to reduce the amount of time that an outdoor worker spends outdoors would provide an effective measure to reduce dose.

Sodium bicarbonate protects uranium-induced acute nephrotoxicity through uranium-decorporation by urinary alkalinization in rats

To evaluate the effectiveness of sodium bicarbonate (SB) in removing uranium and protecting animals from uranium toxicity, we intramuscularly administered 1 mg/kg of uranyl nitrate to 8-wk-old male SD rats, and 20 min after administration of uranyl nitrate, the animals were given a single oral administration of SB at 0.1, 0.3 or 1 g/kg. The SB treatment at a dose of 0.3 g/kg or more raised the pH of the rats’ urine until 4 h after treatment, and it significantly reduced the uranium amounts in the kidneys at 1 day after treatment. In another experiment, rats were intramuscularly administered 1 mg/kg of uranyl nitrate, and 20 min later, the animals were treated with sodium bicarbonate (0.1 or 1 g/kg). The rats were autopsied at 1, 3 and 7 days after uranium treatment. High-dose SB resulted in a significant increase in urinary uranium excretion in the first 24 h and a reduction of uranium deposition in the kidneys and femurs, and it also significantly suppressed uranium-induced renal toxicity, as shown by both histopathology and clinical chemistry at 3 days after uranium treatment. Low-dose SB did not show such marked effects. Our findings demonstrated that the uranium decorporation effect of sodium bicarbonate was observed at the dosage showing urine alkalinization in rats and that decorporation effect of sodium bicarbonate might be beneficial if it is administered immediately after incorporation of soluble uranium.

Tumor induction in mice after local irradiation with single doses of either carbon-ion beams or gamma rays

PURPOSE

To determine the dose-dependent relative biological effectiveness (RBE) for tumor prevalence in mice receiving single localized doses to their right leg of either carbon ions (15, 45 or 75 keV/μm) or 137Cs gamma rays.

METHODS AND MATERIALS

A total of 1647 female C3H mice were irradiated to their hind legs with a localized dose of either reference gamma rays or 15, 45 or 75 keV/μm carbon-ion beams. Irradiated mice were evaluated for tumors twice a month during their three-year life span, and the dimensions of any tumors found were measured with a caliper. The tumor induction frequency was calculated by Kaplan-Meier analysis.

RESULTS

The incidence of tumors from 50 Gy of 45 keV/μm carbon ions was marginally higher than those from 50 Gy of gamma rays. However, 60 Gy of 15 keV/μm carbon ions induced significantly fewer tumors than did gamma rays. RBE values of 0.87 + 0.12, 1.29 + 0.08 or 2.06 + 0.39 for lifetime tumorigenesis were calculated for 15, 45 or 75 keV/μm carbon-ion beams, respectively. Fibrosarcoma predominated, with no Linear Energy Transfer (LET)-dependent differences in the tumor histology. Experiments measuring the late effect of leg skin shrinkage suggested that the carcinogenic damage of 15 keV/μm carbon ions would be less than that of gamma rays.

CONCLUSIONS

We conclude that patients receiving radiation doses to their normal tissues would face less risk of secondary tumor induction by carbon ions of intermediate LET values compared to equivalent doses of photons.

Two Cases of Metastatic Parathyroid Carcinoma in Male C3H Mice Following Irradiation

White nodules were observed in the thyroid in two male C3H mice (at 99 and 122 weeks of age) exposed to fast neutrons at the age of 8 weeks. Histopathologically, in both cases, tumors were developed in the region corresponding to the parathyroid gland, and the tumor cells were arranged in a solid sheet or nest-like structures. Necrosis, cell debris and/or hemorrhage were sometimes seen in the center of the tumor structures. Tumor cells were small and uniform with scanty cytoplasm, cell margins were indistinct, and basally located tumor cells were aligned along the vascular stroma. Mitotic figures were frequently observed. Metastasis to the renal cortex was observed in both cases. These cases were diagnosed as parathyroid carcinoma. A parathyroid tumor is an extremely rare endocrine tumor in mice, regardless of whether the tumor is spontaneous or experimentally induced. These cases may have been induced by neutron-exposure; however, how radiation induces parathyroid carcinoma in mice is not clear.

Prevention of allergic asthma by vaccination with transgenic rice seed expressing mite allergen: induction of allergen-specific oral tolerance without bystander suppression

This study tested the feasibility of oral immunotherapy for bronchial asthma using a newly developed subunit vaccine in which a fragment (p45-145) of mite allergen (Der p 1) containing immunodominant human and mouse T cell epitopes was encapsulated in endoplasmic reticulum-derived protein bodies of transgenic (Tg) rice seed. Allergen-specific serum immunoglobulin responses, T cell proliferation, Th1/Th2 cytokine production, airway inflammatory cell infiltration, bronchial hyper-responsiveness (BHR) and lung histology were investigated in allergen-immunized and -challenged mice. Prophylactic oral vaccination with the Tg rice seeds clearly reduced the serum levels of allergen-specific IgE and IgG. Allergen-induced CD4(+) T cell proliferation and production of Th2 cytokines in vitro, infiltration of eosinophils, neutrophils and mononuclear cells into the airways and BHR were also inhibited by oral vaccination. The effects of the vaccine were antigen-specific immune response because the levels of specific IgE and IgG in mice immunized with Der f 2 or ovalbumin were not significantly suppressed by oral vaccination with the Der p 1 expressing Tg rice. Thus, the vaccine does not induce nonspecific bystander suppression, which has been a problem with many oral tolerance regimens. These results suggest that our novel vaccine strategy is a promising approach for allergen-specific oral immunotherapy against allergic diseases including bronchial asthma.

Selective down-regulation of Th2 cell-mediated airway inflammation in mice by pharmacological intervention of CCR4

BACKGROUND

The chemokine receptor CCR4 has been implicated in Th2 cell-mediated immune responses. However, other T cell subsets are also known to participate in allergic inflammation.

OBJECTIVE

The role of CCR4 in Th1, Th2, and Th17 cell-mediated allergic airway inflammation was investigated.

METHOD

We generated an allergic airway inflammation model by adoptive transfer of in vitro-polarized ovalbumin (OVA)-specific Th1, Th2, and Th17 cells. The effect of a low-molecular weight CCR4 antagonist, Compound 22, on this model was examined.

RESULTS

Upon in vitro polarization of DO11.10 naïve T cells, Th1- and Th2-polarized cells dominantly expressed CXCR3 and CCR4, respectively, while Th17-polarized cells expressed CCR6 and CCR4. Intranasal OVA-challenge of mice transferred with each T cell subset induced accumulation of T cells in the lungs. Eosinophils were also massively accumulated in Th2-transferred mice, whereas neutrophils were preferentially recruited in Th1- and Th17-transferred mice. Compound 22, as well as anti-CCL17 or anti-CCL22 antibody selectively suppressed accumulation of Th2 cells and eosinophils in the lungs of Th2-transferred and OVA-challenged mice. Compound 22 also inhibited bronchial hyperresponsiveness but had little effect on goblet cell hyperplasia in Th2-transferred and OVA-challenged mice.

CONCLUSIONS AND CLINICAL RELEVANCE

There were notable differences in allergic lung inflammation mediated by different T cell subsets. CCR4 blockage was selectively effective for suppression of Th2-mediated allergic inflammation by blocking infiltration of Th2 cells.

Neurobehavioral changes in mice exposed to fast neutrons in utero

Epidemiological studies have revealed that radiation causes brain development abnormalities in atomic bomb survivors exposed in utero. Rat and mouse studies have also shown that prenatal exposure to low-linear energy transfer radiation induces developmental brain anomalies. Because the effects of prenatal irradiation on adult behavior patterns remain largely unknown, the present study investigated the effects of neutron exposure in utero on postnatal behavior patterns in mice. [C57BL/6J × C3H/He] hybrid (B6C3F1) mice were exposed to cyclotron-derived fast neutrons with peak energy of 10 MeV (0.02-0.2 Gy) or Cs-137 gamma-rays (0.2-1.5 Gy) on embryonic day 13.5. At 5.5-8 months of age, the neurobehavior of male offspring was examined by Rota-rod treadmill and locomotor activity. The accumulation of radio-labeled drug at muscarinic acetylcholine and serotonin receptors in mice from control and neutron-irradiated groups was determined by the tracer method. Locomotor activity during the dark period increased in the 0.02 Gy neutron-irradiated group. Furthermore, at 5.5 months of age, tracer binding in vivo to the muscarinic acetylcholine increased and to the serotonin receptors decreased in the 0.02 Gy neutron-irradiated group. In conclusion, the present study reveals that a certain "low-dose window" may exist for radiation-induced changes in neurobehavior and binding to neurotransmitter receptors, because there was correlation in neurobehavior and binding to neurotransmitter receptors in the 0.02 Gy neutron-irradiated group though there was not correlation in the neutron-irradiated groups more than 0.05 Gy.

Pre- and postpubertal irradiation induces mammary cancers with distinct expression of hormone receptors, ErbB ligands, and developmental genes in rats

Childhood exposure to carcinogens renders a higher risk of breast cancer. The molecular mechanisms underlying cancer development after such exposure are not, however, well understood. Here we examined how the mechanism of cancer development relates to the age at exposure to ionizing radiation (IR) or the carcinogen 1-methyl-1-nitrosourea (MNU). Pre- and postpubertal (3- and 7-wk-old, respectively) female Sprague-Dawley rats were whole-body γ-irradiated (2 Gy), injected intraperitoneally with MNU (20 mg/kg) or left untreated and were autopsied at 50 wk of age. Mammary carcinomas were examined for estrogen receptor (ER) α, progesterone receptor (PR) and ErbB ligand expression and for expression microarrays. Early histological changes of the ovaries were also evaluated. The incidence of mammary cancer was higher after postpubertal, rather than prepubertal, IR exposure; the inverse was true for MNU. Most cancers were positive for both ERα and PR except for the prepubertal IR group. Cancers of the prepubertal IR group expressed a different set of ErbB ligands from those of the other groups and did not overexpress Areg, which encodes an estrogen-regulated ErbB ligand, or other developmentally related genes including those for hormonally regulated mammary gland development. Prepubertal IR exposure resulted in ovarian dysfunction as revealed by a reduced follicular pool. Evidence thus suggests that mammary carcinogenesis induced by prepubertal IR exposure is independent of ovarian hormones but requires certain ErbB ligands; induction by postpubertal exposure depends on ovarian hormones and different ErbB ligands. In contrast, the mechanism of MNU-induced carcinogenesis was less influenced by the age at exposure.

Investigation of new cytogenetic biomarkers specific to high-LET radiation usingin vivoandin vitroexposed human lymphocytes

PURPOSE

To find detectable cytogenetic biomarkers that can offer information about the radiation quality of in vivo exposure retrospectively.

MATERIALS AND METHODS

Chromosome-type aberrations of peripheral lymphocytes of uterine cancer patients that received internal gamma- and external X-ray therapy or carbon beam therapy and of victims severely exposed to neutrons and gamma-rays in a criticality accident that occurred in Tokai-mura, Japan were analysed. Data obtained from in vitro irradiation experiments using 60Co gamma-rays and 10 MeV neutrons were compared with the in vivo exposure data.

RESULTS

The ratio of acentric rings to dicentric chromosomes (termed RaD ratio) and that of excess fragments to dicentrics (termed EfD ratio) showed significant (p < 0.05) differences between the two groups of cancer patients, and these ratios for accidental victims were in between the values of the two groups of cancer patients. The in vitro studies using doses equivalent to 1 - 3 Gy of gamma-rays have confirmed that the EfD ratios were increased with the high LET (linear energy transfer) and RaD ratios decreased.

CONCLUSION

The present data show that the RaD and EfD ratios can be used as cytogenetic biomarkers of exposure to high-LET radiation at least within a few years of exposure.

Rapid and reliable diagnosis of murine myeloid leukemia (ML) by FISH of peripheral blood smear using probe of PU. 1, a candidate ML tumor suppressor

Background

Murine myeloid leukemia (ML) provides a good animal model to study the mechanisms of radiation-induced leukemia in humans. This disease has been cytogenetically characterized by a partial deletion of chromosome 2 with G-banding. For the rapid diagnosis of ML, this study reports a FISH method using spleen cells and peripheral blood smears from ML mice exposed to gamma rays and neutrons with PU.1, a candidate ML tumor suppressor, as a probe.

Results

Among mice that were tentatively diagnosed with ML by clinical findings and blood smear examination, 85% carried spleen cells showing the loss of PU.1 although the frequency of these abnormal cells varied among individuals. Mice with very low frequencies of cells showing the loss of one copy of PU.1 (one-PU.1 frequency) were later diagnosed pathologically not with ML but with blastic or eosinophilic leukemia. Some neutron-irradiated mice had cells showing translocated PU.1, although no pathological features differentiated these ML mice from ML mice expressing the simple loss of PU.1.

The one-PU.1 frequency can be detected from spleen metaphase cells, spleen interphase cells, and blood smears. There was a good correlation between the one-PU.1 frequency in spleen metaphase cells and that in spleen interphase cells (r = 0.96) and between one-PU.1 frequency in spleen interphase cells and that in blood cells (r = 0.83).

Conclusion

The FISH method was capable of detecting aberration of copy number of the PU.1 gene on murine chromosome 2, and using a peripheral blood smear is more practical and less invasive than conventional pathological diagnosis or the cytogenetic examination of spleen cells.

Calculation of dose contributions of electron and charged heavy particles inside phantoms irradiated by monoenergetic neutron

The radiation-transport code PHITS with an event generator mode has been applied to analyze energy depositions of electrons and charged heavy particles in two spherical phantoms and a voxel-based mouse phantom upon neutron irradiation. The calculations using the spherical phantoms quantitatively clarified the type and energy of charged particles which are released through interactions of neutrons with the phantom elements and contribute to the radiation dose. The relative contribution of electrons increased with an increase in the size of the phantom and with a decrease in the energy of the incident neutrons. Calculations with the voxel-based mouse phantom for 2.0-MeV neutron irradiation revealed that the doses to different locations inside the body are uniform, and that the energy is mainly deposited by recoil protons. The present study has demonstrated that analysis using PHITS can yield dose distributions that are accurate enough for RBE evaluation.

Defect of the cerebellar vermis induced by prenatal gamma-ray irradiation in radiosensitive BALB/c mice

The developing fetal brain is one of the most susceptible organs to irradiation insult. Prenatal irradiation-induced abnormalities in the cerebrum have been well examined in mouse fetuses. However, little information on abnormalities in the cerebellum caused by irradiation is available. Moreover, few reports have examined the chronological changes of the brain from the prenatal to the postnatal period. To analyze the chronological changes induced by irradiation, we exposed pregnant mice to gamma-ray irradiation on embryonic day 13.5 (E13.5) and investigated the histopathology of the cerebellum at several time points from E14.5 to postnatal day 28. BALB/cA mice were used, which is a radiosensitive strain, and C57BL/6J, which is a radioresistant strain. The irradiated BALB/c showed a remarkable vermis deficit after birth, and histological analysis demonstrated that there were severe losses of the external germinal layer (EGL) and Purkinke cell layer. TUNEL analysis shoed that apoptosis was strongly induce in the cerebellar anlage of the irradiated BALB/c compared to the C57BL/6J at E14.5. Immunohistochemical analysis revealed a significant decrease of phospho-histone H3 positive EGL cells in the irradiated BALB/c at E18.5 and E0, indicating that irradiation causes a decrease in the number of mitotic cells. The results suggest that the strong induction of apoptosis in radiosensitive BALB/c led to a decrease of proliferation activity in the cerebellar anlage during embryonic development, and consequently, severe cerebellar abnormality was evoked.

Microarray-based global mapping of integration sites for the retrotransposon, intracisternal A-particle, in the mouse genome

Mammalian genomes contain numerous evolutionary harbored mobile elements, a part of which are still active and may cause genomic instability. Their movement and positional diversity occasionally result in phenotypic changes and variation by causing altered expression or disruption of neighboring host genes. Here, we describe a novel microarray-based method by which dispersed genomic locations of a type of retrotransposon in a mammalian genome can be identified. Using this method, we mapped the DNA elements for a mouse retrotransposon, intracisternal A-particle (IAP), within genomes of C3H/He and C57BL/6J inbred mouse strains; consequently we detected hundreds of probable IAP cDNA-integrated genomic regions, in which a considerable number of strain-specific putative insertions were included. In addition, by comparing genomic DNAs from radiation-induced myeloid leukemia cells and its reference normal tissue, we detected three genomic regions around which an IAP element was integrated. These results demonstrate the first successful genome-wide mapping of a retrotransposon type in a mammalian genome.

High Relative Biologic Effectiveness of Carbon Ion Radiation on Induction of Rat Mammary Carcinoma and its Lack of H-ras and Tp53 Mutations

PURPOSE

The high relative biologic effectiveness (RBE) of high-linear energy transfer (LET) heavy-ion radiation has enabled powerful radiotherapy. The potential risk of later onset of secondary cancers, however, has not been adequately studied. We undertook the present study to clarify the RBE of therapeutic carbon ion radiation and molecular changes that occur in the rat mammary cancer model.

METHODS AND MATERIALS

We observed 7-8-week-old rats (ACI, F344, Wistar, and Sprague-Dawley) until 1 year of age after irradiation (0.05-2 Gy) with either 290 MeV/u carbon ions with a spread out Bragg peak (LET 40-90 keV/mum) generated from the Heavy-Ion Medical Accelerator in Chiba or (137)Cs gamma-rays.

RESULTS

Carbon ions significantly induced mammary carcinomas in Sprague-Dawley rats but less so in other strains. The dose-effect relationship for carcinoma incidence in the Sprague-Dawley rats was concave downward, providing an RBE of 2 at a typical therapeutic dose per fraction. In contrast, approximately 10 should be considered for radiation protection at low doses. Immunohistochemically, 14 of 18 carcinomas were positive for estrogen receptor alpha. All carcinomas examined were free of common H-ras and Tp53 mutations. Importantly, lung metastasis (7%) was characteristic of carbon ion-irradiated rats.

CONCLUSIONS

We found clear genetic variability in the susceptibility to carbon ion-induced mammary carcinomas. The high RBE for carbon ion radiation further supports the importance of precise dose localization in radiotherapy. Common point mutations in H-ras and Tp53 were not involved in carbon ion induction of rat mammary carcinomas.

Dose-response and large relative biological effectiveness of fast neutrons with regard to mouse fetal cerebral neuron apoptosis

To evaluate the relative biological effectiveness (RBE) of low doses of neutrons on fetal nervous development, [C57BL/6J x C3H/He] hybrid (B6C3F1) mice were exposed to cyclotron-derived fast neutrons with peak energy of 10 MeV (0.02-1.0 Gy) or 137Cs-generated gamma-rays (0.1-2.0 Gy) on embryonic day 13.5. We then evaluated the incidence of neuronal apoptosis in the cerebral cortex 24 hours after irradiation. Neuronal apoptosis increased in a dose-dependent manner in both neutron- and gamma-ray-irradiated groups: even at the lowest dose, a minimal increase in the apoptotic index was noted in response to both types of radiation. The dose-response curves were best fitted to linear quadratic models, and the evaluated RBE was 9.8, which was considered to be large for a prenatal effect and acute tissue injury induced by a low dose of neutrons.

Radiation-induced germline mutations detected by a direct comparison of parents and first-generation offspring DNA sequences containing SNPs

Germline mutation induction has been detected in mice but not in humans. To estimate the genetic risk of germline mutation induction in humans, new techniques for extrapolating from animal data to humans or directly detecting radiation-induced mutations in man are expected to be developed. We have developed a new method to detect germline mutations by directly comparing the DNA sequences of parents and first-generation offspring. C3H male mice were irradiated with gamma-rays of 3, 2 and 1 Gy and 3 weeks later were mated with C57BL female mice of the same age. The nucleotide sequences of 160 UniSTS markers containing 300-900 bp and SNPs of the DNA of parent and offspring mice were determined by direct sequencing. At each dose of radiation, a total of 5 Mb DNA sequences were examined for radiation-induced mutations. We found 7 deletions in 3 Gy-irradiated mice, 1 deletion in 2 Gy-irradiated mice, 1 deletion in 1 Gy-irradiated mice and no mutations in control mice. The maximum mutation frequency was 2.0 x 10(-4)/locus/Gy at 3 Gy, and these results suggested that a non-linear increase of mutations with dose.

Recovery process of arthritis induced by 6-sulfanilamidoindazole (6SAI) in rats

6-Sulfanilamidoindazole (6SAI) is known to induce not only an acute arthritis but also serositis and arteritis which resemble those induced by some vasodilators in rats. In this study, the recovery process of ankle lesions was examined histopathologically for up to 12 weeks of recovery period in rats bearing arthritis induced by administration of 6SAI (500 mg/kg) for 2 weeks. At 2 weeks of 6SAI-treatment, exudative synovitis and exudative/edematous periarthritis with marked formation of granulation tissues and periosteal reactive bone formation were noted in the ankles, but no remarkable neutrophil infiltration was detected in those lesions. The ankle swelling induced by 6SAI diminished by 4 weeks of recovery period, and the elevated plasma fibrinogen levels were normalized by 2 weeks of recovery period. Although fibrosis and newly-formed periosteal bone were still observed after 2 weeks of recovery period, no inflammatory lesion was detected at that point. At 4 or 12 weeks of recovery periods, the ankles showed an almost normal appearance. These results indicate that 6SAI-induced arthritis is reversible in nature and does not develop into chronic phase.

Role of endotoxin in 6-sulfanilamidoindazole(6SAI)-induced arthritis in rats

6-Sulfanilamidoindazole (6SAI) induces selflimiting arthritis in rats. Since close relationships exist between arthritis and endotoxin, four experiments were conducted to clarify the relationship between endotoxin and 6SAI-induced arthritis. Endotoxin levels in the plasma from the abdominal aorta and portal vein from rats that had 6SAI (500 mg/kg) administered orally for up to 7 days remained within the control values at day 1 and day 3, and were significantly elevated at day 7. Endotoxin levels in the synovial fluid from the same rats showed no significant change. Ankle swelling and redness in rats treated 11 consecutive days with 6SAI did not ameliorate when coadministered with an anti-endotoxin agent, polymyxin B sulfate. Histopathological examination on the ankles of rats treated orally with non-arthiritogenic sulfonamides including sulfonamide, sulfamethoxazole and sulfadimethoxin (250 and 500 mg/kg/day, each compound) for 2 weeks demonstrated no inflammatory changes, while hyperplasia/hypertrophy of thyroid epithelial cells were frequently observed. When histopathological changes in the ankles from rats coadministered with 6SAI and lipopolysaccharide (LPS, Escherihia coli O55:B5, 50 microg/kg, i.v.) were compared with those in rats treated with 6SAI or LPS alone, the ankles from the 6SAI+LPS treated animals had marked edematous inflammation in the synovium and surrounding connective tissues, whereas the LPS-group had only mild focal infiltration of polymorphonuclear leukocytes in the synovium and the 6SAI-group showed no apparent changes. These results suggest that endotoxin is not a direct cause but a possible acceralating factor of 6SAI-induced arthritis, and that the effects of 6SAI on gut bacteria is not related with the pathogenesis of this model.

Regression by ACE inhibition of arteriosclerotic changes induced by chronic blockade of NO synthesis in rats

We previously reported that chronic inhibition of nitric oxide (NO) synthesis with N(omega)-nitro-L-arginine methyl ester (L-NAME) induces vascular inflammation at week 1 and produces subsequent arteriosclerosis at week 4 and that cotreatment with an angiotensin-converting enzyme (ACE) inhibitor prevents such changes. In the present study, we tested the hypothesis that treatment with an ACE inhibitor after development of vascular inflammation could inhibit arteriosclerosis in rats. Wistar-Kyoto rats were randomized to four groups: the control group received no drugs, the 4wL-NAME group received L-NAME (100 mg x kg(-1) x day(-1)) for 4 wk, the 1wL + 3wNT group received L-NAME for 1 wk and no treatment for the subsequent 3 wk, and the 1wL + 3wACEI group received L-NAME for 1 wk and the ACE inhibitor imidapril (20 mg x kg(-1) x day(-1)) for the subsequent 3 wk. After 4 wk, we observed significant arteriosclerosis of the coronary artery (medial thickening and fibrosis) and increased cardiac ACE activity in the 1wL + 3wNT group as well as in the 4wL-NAME group, but not in the 1wL + 3wACEI group. In a separate study, we examined apoptosis formation and found that posttreatment with imidapril (20 mg x kg(-1) x day(-1)) or an ANG II AT1-receptor antagonist, CS-866 (5 mg x kg(-1) x day(-1)), induced apoptosis (TdT-mediated nick end-labeling) in monocytes and myofibroblasts appearing in the inflammatory lesions associated with a clear degradation in the heart (DNA electrophoresis). In conclusion, treatment with the ACE inhibitor after 1 wk of L-NAME administration inhibited arteriosclerosis by inducing apoptosis in the cells with inflammatory lesions in this study, suggesting that increased ANG II activity inhibited apoptosis of the cells with inflammatory lesions and thus contributed to the development of arteriosclerosis.

Effects of imidapril and captopril on streptozotocin-induced diabetic nephropathy in mice

We investigated whether the prevention of the development of diabetic nephropathy by angiotensin-converting enzyme inhibitors is associated with decreases in renal angiotensin-converting enzyme activity and/or blood pressure in diabetic mice. C57Bl/6 mice were injected with streptozotocin (200 mg/kg, i.v.) and randomized to receive either imidapril (1 and 5 mg/kg) or captopril (10 and 50 mg/kg) or vehicle by gavage for 28 days. Each assay was performed on 8-10 mice from each treatment. At 28 days after the start of drug treatment, imidapril and captopril significantly reduced blood pressure of the diabetic mice, and this effect of captopril was stronger than that of imidapril. On the other hand, inhibition of renal angiotensin-converting enzyme activity by imidapril was stronger than that by captopril. Imidapril and captopril dose-dependently inhibited urinary albumin excretion to similar extents, but they failed to inhibit the renal hypertrophy and elevation of creatinine clearance. Total renal angiotensin-converting enzyme activity was significantly reduced in diabetic mice, but immunohistochemical localization of angiotensin-converting enzyme was intensive in the vasculature and glomeruli of the diabetic kidney. In conclusion, both effects on blood pressure and angiotensin-converting enzyme activity may be involved in the prevention of development of diabetic nephropathy by imidapril and captopril in streptozotocin-induced diabetic mice. The data suggest that the degrees of contribution of their effects on blood pressure and renal angiotensin-converting enzyme activity to the inhibition of urinary albumin excretion may be different between the two angiotensin-converting enzyme inhibitors.

Localization of the histamine H(2) receptor, a target for antiulcer drugs, in gastric parietal cells

BACKGROUND/AIMS

Histamine H(2) receptor antagonists are widely used for the treatment of peptic ulcer disorders. However, whether the H(2) receptor is present in parietal or immune cells in the lamina propria remains controversial. This study is designed to determine the H(2) receptor localization immunohistochemically using an antibody against the newly cloned mouse histamine H(2) receptor.

METHODS

We cloned the mouse histamine H(2) receptor gene and generated a specific antipeptide antibody against the C terminus. Immunohistochemical studies were performed with this antibody and with a monoclonal antibody against H(+)/K(+) adenosine triphosphatase (ATPase).

RESULTS

Histamine H(2) receptors were localized on the plasma membrane and on the cytoplasm just beneath the plasma membrane on the basolateral sides of gastric cells. Confocal microscopy of double-stained sections using the monoclonal antibody against H(+)/K(+) ATPase, a specific parietal cell marker, showed that histamine H(2) receptors colocalized with H(+)/K(+) ATPase. No specific histamine H(2) receptor immunoreactivities were observed in the submucosal regions.

CONCLUSION

The H(2) receptor is localized in the gastric parietal cell.

A novel sperm-specific hypomethylation sequence is a demethylation hotspot in human hepatocellular carcinomas

Certain human DNA regions are strikingly undermethylated at CpG sites in sperm compared to adult somatic tissues. These sperm-specific hypomethylation sequences are thought to function early in embryogenesis or gametogenesis. By using the restriction landmark genomic scanning (RLGS) cloning method, we have isolated a novel sperm-specific hypomethylation sequence, the status of which changes during spermatogenesis, embryonal growth and differentiation. This sequence is a part of a new 'NotI repeat' consisting of a 1.4 kb repetitive unit sequence named DE-1. The sequence is GC-rich and has high homology to a CpG DNA clone that was isolated by a methyl CpG protein binding column, indicating that it was normally highly methylated. We investigated the methylation status of this sequence. In the normal genome the sequence was methylated, but in the human hepatocellular carcinoma (HCC) genome, the target sequence was demethylated at the cytosine residue of the CpG dinucleotides with high frequency (75% in the previous study). These data suggest that this regional DNA hypomethylation may play a role in both cell differentiation and hepatocarcinogenesis.

Novel, potent, and selective phosphodiesterase-4 inhibitors as antiasthmatic agents: synthesis and biological activities of a series of 1-pyridylnaphthalene derivatives

The structural requirements for potent and selective PDE4 inhibition were revealed in a 1-pyridylnaphthalene series, and the best compound (3kg, T-2585.HCl) was chosen for further biological evaluation (PDE4 inhibition IC50 = 0.13 nM, selectivity PDE3/4 ratio = 14 000). Compound 3kg showed potent antispasmogenic activities (ED50 = 0.063 mg/kg for reduction of antigen-induced bronchoconstriction, intravenously; ED50 = 0.033 mg/kg for reduction of histamine-induced bronchoconstriction, intraduodenally) in guinea pigs with little cardiovascular effects. Furthermore, 3kg induced significantly weaker emetic effects than RP73401 after oral administration in ferrets and intravenous administration in dogs (3kg, none of 4 ferrets vomited at a dose of 10 mg/kg, po and none of 8 dogs vomited at a dose of 0.3 mg/kg, iv; RP73401, 4 of 8 ferrets vomited at a dose of 3 mg/kg, po and 6 of 8 dogs vomited at a dose of 0.3 mg/kg, iv); that is compatible with the lower affinity for the high-affinity rolipram binding site (3kg, 2.6 nM; RP73401, 0. 85 nM). This may imply that 3kg has an improved therapeutic ratio because of a broad margin between the Ki value of binding affinity and the IC50 value of PDE4 inhibition (ratio = 0.050).

Identification of novel pancreas-specific regulatory sequences in the promoter region of human pancreatic secretory trypsin inhibitor gene

The human pancreatic secretory trypsin inhibitor (PSTI) genes introduced into mice are specifically expressed in pancreas. The 1.0 kilobase pairs of PSTI 5'-flanking sequence directed preferential expression of a linked reporter chloramphenicol acetyltransferase, which was active in a PSTI-expressing pancreatic cell line (AR42j) but not in a PSTI-nonexpressing fibroblast cell line (XC). Two positively acting elements were found, Region I (-161/-116) and Region II (-103/-74), as defined by transfection and binding assays with AR42j cells. Region II is sufficient for the pancreas-specific expression, but the presence of both Regions I and II is needed for the maximum activity. Sequence studies also revealed that these two elements differ from the previously identified recognition sequence for pancreas transcription factor 1 (PTF1). When the same set of experiments was done with XC cells, one negatively acting element was identified, Region IV (-154/-137). Interestingly, Regions I and IV share a core sequence (-149/-139), CAATCAATAAC. These results suggest that this novel element regulates the human PSTI gene expression positively in pancreatic cells but negatively in nonpancreatic cells.

Involvement of angiotensin II in development of spontaneous nephrosis in Dahl salt-sensitive rats

We investigated the effect of angiotensin-converting enzyme inhibition on spontaneous nephrosis in Dahl salt-sensitive (Dahl/S) rats. Dahl/S rats fed on a normal sodium diet spontaneously developed nephrosis and mild hypertension from a young age. In young Dahl/S rats, an angiotensin-converting enzyme inhibitor, imidapril, attenuated the development of proteinuria accompanied by a decrease in blood pressure. Methylprednisolone, a potent therapeutic agent for proteinuria, did not affect the development of nephrosis. An angiotensin AT1 receptor antagonist, losartan, but not a Ca2+ channel blocker, verapamil, inhibited the development of nephrosis while both agents decreased blood pressure to a similar extent as imidapril. In mature Dahl/S rats, imidapril suppressed not only the development of proteinuria but also the glomerular lesions. It is concluded that the development of spontaneous nephrosis in Dahl/S rats is mediated by angiotensin II.

Systemic histopathology of rats treated with 6-sulfanilamidoindazole, a novel arthritogenic sulfonamide

6-Sulfanilamidoindazole (6SAI) is a sulfonamide that induces acute, self-limiting arthritis in rats, and 6SAI-induced arthritis is thought to be a model for testing anti-inflammatory agents. In this study, in order to clarify the location of arthritis and relationships between arthritis and other changes in this model, we have investigated the detailed pathologic changes in rats administered orally with 6SAI (125, 250, 500 mg/kg) daily for 4 wk in a time-course experiment. Moderate to severe arthritis was observed in rats of middle- and high-dose groups. Histologically, in the affected ankle, exudative synovitis and periarthritis were observed at 1 wk, granulation tissue formation with angiogenesis and periosteal new bone formation at 2 wk, and marked fibrosis of affected area at 4 wk, respectively. In addition to these changes, in periarticular and periosteal tissues of affected ankles, subendothelial insudation of small-sized arteries and medial fibrinoid degeneration of medium-sized arteries were observed at 1 and 2 wk and intimal thickening and medial hypertrophy at 4 wk, respectively. No arterial changes were observed in the unaffected ankles. Similar arterial changes were often observed in the liver, thyroid glands, and lungs and rarely in various organs and tissues. Acute inflammation of serous tissues such as mesentery, mediastinum, and capsule of spleen or thymus were also present in 6SAI-treated groups, and it was sometimes accompanied by arteritis. In addition, in 6SAI-treated rats, follicular hyperplasia of thyroid glands and pituitary changes, which are thought to be related to depression of thyroid hormone production by 6SAI, were observed. These results show that 6SAI induces not only arthritis but also arteritis, serositis, and thyroid change, and it is necessary to take the interaction between these changes into consideration when anti-inflammatory agents are tested in this model.

The effect of dexamethasone on the expression of activated NF-kappa B in adjuvant arthritis

The transcription factor NF-kappa B plays a significant role in inflammatory diseases. In this study we have investigated the expression of activated NF-kappa B p65 subunit in the rat adjuvant arthritis model in a 28-day time-course experiment using immunohistochemistry. The expression of p65 was detected in the synovial lining layer and around the blood vessels in the inflamed synovium as early as Day 3 post-adjuvant injection. The cells that expressed p65 in the synovial lining were thought to be macrophage-like synoviocytes. The expression was stronger in the injected hindpaw than that in the noninjected hindpaw. Dexamethasone treatment at 1 mg/kg p.o. (Days 0-20) suppressed both the hindpaw edema and increase in p65 expression. Withdrawal of the treatment caused increases in both p65 expression and paw volume. Together these suggest that activated NF-kappa B was specifically expressed in the arthritic synovium and may play a significant role in the development of arthritis.

Phenytoin-induced cerebral thrombosis in rats: cerebral ultrastructure, water content and ischaemic volume in the acute phase

A new rat model for multifocal cerebral thrombosis has recently been reported (Tani et al., 1994; 1995). Ultrastructural changes in the cerebral neocortex in the acute phase were investigated in order to characterize the early pathological events in this model. A bolus injection of alkaline phenytoin solution (pH 10.8) into one internal carotid artery in the rat caused severe endothelial injury accompanied by thrombosis in the cerebral vasculature within 5 minutes, and severe oedema of the ipsilateral hemisphere within an hour. Cerebral water content was measured by the simple dry-wet method, and cerebral surface area and the surface area and volume of the ischaemic zone were measured using computer-aided image analysis. Good correlations were demonstrated between cerebral water content and cerebral surface area, and between the surface area and volume of the ischaemic zone. We report here that quantitative evaluation of acute cerebral damage induced by phenytoin solution is possible with high reliability using simple image analysis.

Prolonging action of imidapril on the lifespan expectancy of cardiomyopathic hamsters

We studied the effect of imidapril, a novel angiotensin-converting enzyme (ACE) inhibitor, on lifespan expectancy of cardiomyopathic (CM) hamsters of BIO 14.6 strain, one of the representative models of congestive heart failure (CHF). Imidapril was consecutively administered to hamsters by mixing it in their diet at a concentration of 480 ppm (approximately 30 mg/kg/day) or 1,600 ppm (approximately 120 mg/kg/day) from age 26 weeks. Only several control hamsters died before age 54 weeks, but their survival rate decreased to 23.7% at age 73 weeks. The survival rates of 480-ppm and 1,600-ppm imidapril groups at age 73 weeks were as high as 75.7 and 68.4%, respectively (p < 0.01 vs. control hamsters). Macroscopic and microscopic pathology in imidapril-treated groups was milder than that in control animals in general, but differences were not statistically significant when animals were divided into survivors and fatalities except for the presence of mural thrombus in the heart. We further studied the effects of imidapril on blood pressure (BP), in vivo cardiac function, cardiac beta-adrenoceptor distribution, and plasma catecholamine levels after dietary treatment with 480 ppm imidapril for 8-10 weeks from age 37 weeks. Imidapril-treated animals showed improved cardiac function under urethane anesthesia. These results indicate that imidapril prolongs lifespan expectancy of CM hamsters and suggest that a hemodynamic effect of imidapril is involved in its beneficial effect.

Strain differences in vulnerability of hippocampal neurons to transient cerebral ischaemia in the rat

Strain differences in the vulnerability of hippocampal neurons to an ischaemic insult were investigated in Sprague-Dawley, Wistar and Fischer 344 rats. Transient global brain ischaemia was produced for 5 minutes by a combination of bilateral carotid artery occlusion and oligaemic hypotension (40 mmHg) induced by exsanguination. The number of viable neurons in the CA1 subfield was counted under a light microscope 7 days after the ischaemic insult. The density of viable neurons in the CA1 subfield of normal rats was around 150 cells/mm of CA1 length in all the strains examined; after global brain ischaemia, this parameter in Sprague-Dawley, Wistar and Fischer 344 strain rats was approximately 110, 120, and 70, respectively. The results suggest that the hippocampal CA1 neurons of Fischer 344 strain rats are more vulnerable to ischaemic insult than those of the other strains. There were many F344 rats (8/21) which showed atypical vasculature patterns in the posterior region of the circle of Willis, suggesting less blood flow through anastomosis from basilar artery to posterior cerebral artery and/or ill-balanced blood flow between left and right hemispheres. These anatomical variations in the circle of Willis may in part contribute to the strain differences in the vulnerability to cerebral ischaemia.

Expression of the pancreatic secretory trypsin inhibitor gene in the liver infected with hepatitis B virus

Pancreatic secretory trypsin inhibitor, an acute phase reactant protein, is expressed in the liver in response to inflammatory cytokines, especially in hepatocellular carcinoma. Northern blots of 25 dissected liver tissues from non-hepatitis, chronic hepatitis and cirrhosis patients revealed that 10 (40%) expressed pancreatic secretory trypsin inhibitor. The expression seemed to be closely associated with hepatitis B viral infection, since among the 11 hepatitis B virus-infected samples, nine (81%) were pancreatic secretory trypsin inhibitor-positive. In contrast, this augmented expression was absent in non-infected livers (0/5; 0%), and rare in those infected with hepatitis C virus (1/9; 11%). There was no significant correlation between the pancreatic secretory trypsin inhibitor expression in the liver and the serum level of glutamic pyruvic transaminase, the hepaplastin test, the 15-min retention rate of indocyanine green, or the histological findings of the liver tissues such as lymphocyte infiltration and pseudolobular formation. Furthermore, we identified an almost three-fold increase in the transactivation of pancreatic secretory trypsin inhibitor gene expression in HepG2 cells after transient transfection with HBV-DNA or the X gene in an expression vector. These results suggest that the induction of pancreatic secretory trypsin inhibitor gene expression in livers with chronic hepatitis and cirrhosis is directly affected by hepatitis B virus.

Hepatic changes of mice in the subacute phase of streptozotocin (SZ)-induced diabetes

Hepatic changes of mice in the subacute phase of streptozotocin (SZ)-induced diabetes were investigated biochemically and pathologically. Biochemically, the contents of serum glucose and of serum and liver lipids increased while the content of liver glycogen decreased in SZ-induced diabetic mice. Histopathologically, hypertrophy of hepatocytes due to an increase in number of intracytoplasmic acidophilic granules was common to SZ-induced diabetic mice. Electron microscopically, these hepatocytes were characterized by a prominent increase in number of mitochondria showing normal structure, a marked decrease of glycogen granules and poorly developed rough endoplasmic reticulum, which were common to so-called oncocytic cells. In some SZ-induced diabetic mice, bile duct hyperplasia with an appearance of cytomegalic hepatocytes was also observed.

Enhanced attachment and elastase-releasing capacity of neutrophils after surgery

Perioperative changes in neutrophil attachment level and neutrophil elastase-releasing capacity were examined in patients who underwent surgery for either esophageal or gastric cancer. The neutrophil attachment level was significantly increased in both groups to approximately three times that of the preoperative value. The elastase-releasing capacity of nonstimulated neutrophils was not significantly changed, but it was significantly increased in neutrophils stimulated by N-formyl-L-methionyl-L-leucyl-L-phenylalanine (FMLP). Moreover, both neutrophil attachment and elastase-releasing capacity of FMLP-stimulated neutrophils were more enhanced in patients with postoperative complications than in patients without complications. Peak levels of serum interleukin 6, serum alpha 1 proteinase inhibitor, and plasma neutrophil elastase were also significantly higher in patients with postoperative complications than in patients without. These results suggest that during the postoperative period, neutrophils may be primed and activated in response to inflammatory mediators such as cytokines, and that such an alteration of neutrophil functions may reflect the extent of inflammation and may, at times, be implicated in postoperative complications.

Aberration of genomic DNA in association with human hepatocellular carcinomas detected by 2-dimensional gel analysis

Alterations of genomic DNAs in primary hepatocellular carcinomas (HCCs) were examined by restriction landmark genomic scanning (I. Hatada et al., Proc. Natl. Acad. Sci. USA, 88: 9523-9527, 1991) which is a 2-dimensional gel analysis that allows detection of deletion, amplification, or other rearrangements of genomic DNA. Sixteen HCC samples together with their normal counterparts were tested in this manner. Each HCC sample was micromanipulated to minimize possible carryover from non-malignant cells. DNAs from HCCs and their normal counterparts were cleaved with the restriction enzyme NotI, end labeled with 32P, and size fractionated by 2-dimensional electrophoresis using HinfI as the second cleavage enzyme. The resulting spots (about 2000) in HCC samples were compared with their normal counterparts. Five spots were more intense in 10-14 of the 16 HCCs (63-88%). The intensity of several spots was reduced to about half, suggesting the loss of one of two alleles. Some of these decreases were observed frequently in different HCC samples, whereas others were sporadic. Sixty of these spots reproducibly decreased in > 2 cases, with 27 showing a decrease in > 50% of the informative cases. The highest incidence was observed in 14 of 16 samples (88%). No significant correlations were observed between these changes in spots and hepatitis B virus or hepatitis B virus infection. The use of landmarks that show a reproducible increase or decrease in intensity is discussed in conjunction with future studies of genomic alterations inherent in HCC.

Overexpression of pancreatic secretory trypsin inhibitor in pancreatic cancer. Evaluation of its biological function as a growth factor

Four clones of pancreatic secretory trypsin inhibitor (PSTI)-overexpressing cells (TF-PANC clones 1, 6, 8, and 36) were established to evaluate the physiological function of PSTI secreted by cancer cells, by means of introducing a PSTI-expression vector (pRSV-PSTI) into the human pancreatic adenocarcinoma cell line (PANC-1). No obvious changes were observed in the histological features of these transplanted tumors in nude mice, in the growth of TF-PANC and PANC-1, or that of 3T3 fibroblasts when cocultured with them. Addition of recombinant human PSTI to the cultured media resulted in no increase in proliferation of fibroblasts (3T3 and WI-38) or of four pancreatic cancer cell lines (PANC-1, CAPAN-I, MIAPaCa-2, and Hs766T). These results suggest that the estimation of tumor-bearing PSTI as a paracrine or autocrine growth factor in recent studies should be given careful consideration.

Specific expression of the pancreatic-secretory-trypsin-inhibitor (PSTI) gene in hepatocellular carcinoma

Twenty hepatocellular carcinomas (HCC) were analyzed by Northern blotting to test the expression of pancreatic secretory trypsin inhibitor (PSTI). This gene was expressed in all HCCs, but not in other tumors, including mammary, thyroid, pulmonary and ovarian cancers. Some gastric and colonic cancers weakly expressed PSTI. Among cell lines examined in a similar manner, PSTI was expressed in all of 4 derived from hepatoma. On the other hand, among 15 cell lines derived from cancers other than hepatoma, only 3, derived from pancreatic, colonic and gastric cancers, weakly expressed PSTI. A CAT assay using a deletion set of the 5' region from the cloned PSTI gene has shown that in hepatoma cell lines, the expression of this gene is dependent on the presence of 2 regulatory regions that include an IL-6 responsive elements and an AP-I-binding site. However, in non-hepatoma cell lines, the 2 regulatory regions are not necessary for expression. The blood level of PSTI in 27 patients with HCC was significantly increased, and it was positively correlated with tumor size, suggesting that specific expression of PSTI in HCC causes this effect and that elevated blood level of PSTI without inflammation indicates the presence of HCC.

Identification of the IL-6-responsive element in an acute-phase-responsive human pancreatic secretory trypsin inhibitor-encoding gene

Pancreatic secretory trypsin inhibitor (PSTI) has been suggested to be an acute-phase reactant in humans and to be induced by inflammatory cytokines such as the interleukins IL-1 and IL-6. We report that PSTI is synthesized in hepatoma cells and that the gene expression is augmented by IL-6. The start points (tsp) for basal and augmented transcription are exactly the same as the tsp in normal pancreas. Analysis of the PSTI gene revealed that a 40-bp DNA fragment located between kb -3.84 and -3.80 carries the element responsible for both transcriptional activity and IL-6-induced gene expression. This 40-bp fragment contains TTGNNGNAATG, the consensus sequence for the NF-IL6-binding site, which is also known as the IL-6-responsive element that is conserved among various acute-phase genes. The basal activity was augmented by another sequence that lies between kb -4.0 and -3.9.

[Establishment of EGF, EGF-R and FN-R positive human adenocarcinoma cell line (GAC-1)]

A human adenocarcinoma cell line designated as GAC-1, was established from ascites of the 56-year old male patient with rapidly progressive gastric cancer. The doubling time was about 18.5 hours in vitro, and cell cycle analysis using flow cytometry showed marked increase of S phase (46.1%). Immunohistochemical demonstration of GAC-1 cells revealed positive staining of TGF-alpha, EGF, EGF-R, FN-R, laminin and negative staining of fibronectin. Histogram of them indicated aneuploidy with modal number 57 and they formed tumors in nude mice.

[Intra-arterial infusion chemotherapy in locally recurrent breast cancer]

Intra-arterial infusion chemotherapy (IA) using implantable reservoir was performed in four locally recurrent breast cancers. The regimen consisted of several cycles of induction (1 cycle, 90-150mg: EPI) and the following maintenance infusion. The results were as follows. (1) D.F.I. of all cases were short and pre-treatment of 3 cases was not effective. (2) Clinical response was 2 CR and 1 MR. We confirmed that IA was an effective treatment for not only locally recurrence but also disseminated foci. (3) In 3 out of the four cases there was reduction of severe arm swelling. These findings suggested that IA using implantable reservoir was useful for the treatment of locally recurrent breast cancer in terms of anti-cancer effect and improved QOL.

Circulating interleukin 6 as a useful marker for predicting postoperative complications

We examined postoperative serial changes in the levels of serum interleukin 6 (IL-6), serum acute phase reactants (APRs) and plasma neutrophil elastase (NE) in patients with various cancers and reviewed these changes in patients who did, and did not, show postoperative complications. Serum IL-6 level was elevated after surgery, peaking on the first postoperative day. Elevation of serum APRs and plasma NE levels also followed. There was a significant correlation between the serum peak level of IL-6 and those of APRs and NE (P less than 0.01). Moreover, there was a significant difference in the serum IL-6 level in patients with and without complications. The relationship between the serum IL-6 greater than 400 pg/ml and the incidence of postoperative complications was also marked. These results suggest that circulating IL-6 is a clinically useful marker for the earliest detection and prediction of postoperative complications.