RECENT TRITIUM CONCENTRATION OF MONTHLY PRECIPITATION IN JAPAN

To obtain a better understanding of recent tritium concentration and its seasonal cycle in Japan, monthly precipitation samples were collected in Hokkaido, Gifu and Okinawa prefectures from June 2014 to December 2017. The arithmetic mean ( ± standard deviation) of tritium concentrations in precipitation samples from Hokkaido, Gifu and Okinawa were estimated to be 0.62 ± 0.27 Bq L-1, 0.32 ± 0.12 Bq L-1 and 0.13 ± 0.05 Bq L-1, respectively. These results indicate that the concentrations increase with latitude. In addition, the highest and the lowest concentrations appeared in spring and summer, respectively. To clarify the origins and sources of these cycles, further analyses of chemical compositions of precipitation and meteorological conditions are needed.

TRITIUM, HYDROGEN AND OXYGEN ISOTOPE COMPOSITIONS IN MONTHLY PRECIPITATION SAMPLES COLLECTED AT TOKI, JAPAN

Monthly precipitation samples have been collected at Toki, Japan, from November 2013 to March 2017. In this report, selected data were analysed to identify the regional hydrogen and oxygen isotope compositions. Tritium (3H) concentration in the precipitation ranged from 0.10 to 0.61 Bq L-1 and higher 3H concentrations were observed in spring rather than in other seasons. This range was similar to values reported in Chiba City, Japan. 3H concentration and the ratio d-excess, and δD values were roughly clustered according to each separate season. These regional hydrogen and oxygen isotope compositions will be used for environmental assessments of effects of the deuterium plasma experiments of the large fusion test device.

FWT and OBT concentrations in pine needle samples collected at Toki, Japan (1998-2012)

Free water tritium (FWT) and organically bound tritium (OBT) concentrations in pine needles have been investigated to understand the regional background tritium concentration in Toki City. Samples were regularly collected from pine trees on the National Institute for Fusion Science campus (1998-2012) and the nearby Shiomi Park (SP; 2002-12). FWT and OBT concentrations of the former samples ranged from 0.33 to 0.92 and 0.41 to 1.10 Bq l(-1), respectively, while those of the latter samples ranged from 0.32 to 0.86 and 0.33 to 0.79 Bq l(-1), respectively. Results of both sampling sites were almost the same, and they have been gradually decreased year by year. Concentration level of tritium for Toki City was close to the average background level in Japan. The OBT/FWT ratios were almost 1.0. The apparent half-life of FWT in this period was estimated as almost 10 y, and that of OBT was estimated as almost 12 y; these values were almost the same as the physical half-life.

An atomically controlled Si film formation process at low temperatures using atmospheric-pressure VHF plasma

To grow epitaxial Si films with atomic- and electronic-level perfection, a high-temperature chemical vapor deposition (CVD) process (>1000 °C) has been generally employed. To reduce the growth temperature below 600 °C but keeping a high deposition rate, other energy sources than thermal heating are required. Atmospheric pressure plasma CVD (AP-PCVD) is considered to be suitable for fabricating high-quality films at high deposition rates due both to the high radical density and to the low ion bombardment against the film surface, because the collision frequency among ions and neutral atoms is high. The present study focuses on the low-temperature growth of epitaxial Si, and experimentally demonstrates that AP-PCVD is capable of growing epitaxial Si films with high perfection applicable for semiconductor devices. It is found that the pre-growth cleaning of the Si surface by H(2) AP plasma is effective to grow high-purity Si films, and that the exposure of a film-growing surface to AP plasma during growth is important to form particle-free and defect-free Si films. From the experimental results and the first-principles molecular dynamics simulations of surface atomic reactions, it can be mentioned that both H atoms in the AP plasma and high-density He atoms having thermal kinetic energy contribute to the reduction of growth temperature by supplying considerable energy to the surface.

[Evaluation of postoperative pain relief by infiltration of bupivacaine or epidural block after laparoscopic cholecystectomy]

We compared the analgesic effect of bupivacaine infiltration into surgical wounds with that of epidural block after laparoscopic cholecystectomy (LC). Forty-five patients (ASA physical status I-II) for LC were randomized into three groups (n = 15 in each group). Patients received only general anesthesia (Group C), received infiltration of 0.5% bupivacaine into the surgical wound before surgery combined with general anesthesia (Group L), or received epidural anesthesia combined with general anesthesia (Group E). Postoperative pain was assessed using visual analogue scale (scale: 0-10) at 1, 2, 6 and 12 hours after the operation, the need for additional supplemental analgesics, and the cost of anesthesia. Visual analogue scale in Group C at 1, 2, or 6 hours was significantly greater than that of Group L and E. The number of patients who needed supplemental analgesics was 9 in Group C, 5 in Group L, and 2 in Group E. The cost of pharmaceutical and anesthetic practice of Group E was more expensive than Group L and C. In conclusion, infiltration of bupivacaine combined with general anesthesia is an effective and economical method of postoperative pain relief.

Absence of microsatellite instability and germline mutations of E-cadherin, APC and p53 genes in Japanese familial gastric cancer

To evaluate the genetic factors of familial predisposition to gastric cancer, genetic alterations in the surgically resected stomach samples from gastric-cancer-prone families were investigated. Familial gastric cancer (FGC) was defined as gastric cancer occurring in a family with 3 or more gastric cancer patients over at least two successive generations. We examined replication error (RER) of six microsatellite markers and screened mutations of the 10-(A) repeat sequence in the transforming growth factor-beta receptor type II (TGF-betaRII) gene in individuals from seven unrelated FGC families. Three cases showed RER at one of the six (CA)n microsatellite markers but the other 4 cases showed no RER at any of these loci. No mutation was found in the 10-(A) repeat of the TGF-betaRII gene. Additionally, no germline mutation was found by polymerase chain reaction-single strand conformation polymorphism in exons 1-16 of E-cadherin, exons 5-8 of p53 and in the mutation cluster region of APC. These results indicate that disorders in the DNA mismatch repair system, E-cadherin, p53 and APC may be infrequently involved in the carcinogenesis of Japanese FGC.

A simple objective parameter for perfusion study of renal transplant

We proposed a simple parameter, the kidney-to-aorta ratio (KAR), for evaluation of renal transplant perfusion. KAR was calculated from the peak counts of the kidney and the aorta. The calculated values were compared with the visual interpretation of the radionuclide first-pass flow study, percent renal uptake (%RU), and tubular extraction rate (TER) by Bubeck's one point sampling method in 37 studies. KAR correlated well with the visual interpretation of the flow study and the other quantitative parameters. Representative cases, which showed the usefulness of KAR for the objective assessment of the perfusion status of renal transplants, were presented. In conclusion, KAR is a simple and practically useful parameter for objective evaluation and follow-up of renal transplant perfusion.

Inactivation of the 14-3-3 sigma gene is associated with 5' CpG island hypermethylation in human cancers

The cell cycle checkpoint plays an important role in maintaining the integrity of cells. Recently, one of the 14-3-3 protein family members, 14-3-3sigma, was shown to be regulated by p53 and to play a role in the G2-M-phase checkpoint. To determine whether 14-3-3sigma is inactivated in human cancers, the methylation status of the 5' region of 14-3-3sigma was investigated in a series of gastric, colorectal, and hepatocellular cancer cell lines. Of 22 cell lines examined, 6 showed aberrant methylation. The methylation status of 14-3-3sigma was found to be correlated with loss of expression, which was restored by 5-aza-2'-deoxycytidine treatment. Furthermore, normal G2 arrest after DNA damage was not demonstrated in the cell lines with methylation. In primary gastric cancers, 14-3-3sigma hypermethylation was observed frequently in 26 of 60 (43%) cases and observed more frequently in poorly differentiated adenocarcinomas (P = 0.0017). Our findings suggest that 14-3-3sigma is inactivated by aberrant methylation of the 5' region in various human cancers and that it might play an important role in the development of undifferentiated gastric cancers.

Quantitative DNA methylation analysis by fluorescent polymerase chain reaction single-strand conformation polymorphism using an automated DNA sequencer

A novel DNA methylation assay technique, termed bisulfite single-strand conformation polymorphism (bisulfite-SSCP), is a combination of sodium-bisulfite modification and fluorescence-based polymerase chain reaction (PCR)-SSCP. After bisulfite treatment followed by PCR amplification, methylated and unmethylated alleles can be simultaneously separated in a nondenaturing gel using an automated DNA sequencer. Using bisulfite-SSCP, methylation of hMLH1 was detected in a quantitative manner. This method is not only simple, quick, accurate, and quantitative, but detailed information about methylation is also available with less work. Methylation analysis of large numbers of samples for multiple loci will be facilitated by bisulfite-SSCP.

[Prediction of the clinical efficacy of hepatic arterial chemotherapy for metastatic hepatic cancer by intraarterial infusion of 99mTc-MIBI]

SPECT was performed in 11 patients with metastatic hepatic cancer by intraarterial infusion of 99mTc-MIBI before hepatic arterial chemotherapy was started, and the degree of accumulation and clinical efficacy were compared. Early and delayed SPECT images were obtained and various parameters were calculated, including early ratio (ER), delayed ratio (DR), washout rate (WR), and retention index (RI). Judgement of clinical efficacy was made by CT before and after hepatic arterial chemotherapy and was classified as effective, unchanged, and progressive groups. The mean values of ER and DR in the effective group were higher than those in the progressive group. No relationships were noted among the WR and RI values of the groups. The assessment of ER and DR using 99mTc-MIBI intraarterial SPECT is considered to be useful for prediction of the clinical efficacy of hepatic arterial chemotherapy for metastatic hepatic cancer.

Distinct methylation pattern and microsatellite instability in sporadic gastric cancer

Aberrant 5' CpG island methylation is an alternative mechanism of gene inactivation during the development of cancer as demonstrated for several tumor-suppressor genes. Also, marked relationship of microsatellite instability (MSI) and DNA methylation has been reported in sporadic colorectal cancer, which is a result of epigenetic inactivation of hMLH1 in association of promoter hypermethylation. In the present study, we investigated the 5' CpG island hypermethylation of hMLH1, E-cadherin and p16 in 61 primary gastric cancers (GCs) by using combined bisulfite restriction analysis (COBRA) and methylation-specific PCR (MSP), and their MSI status. Of 61 GCs investigated, 5 (8.1%) tumors presented hMLH1 methylation, 16 (26.2%) and 25 (40.9%) showed E-cadherin and p16 methylation respectively, and 8 (13.1%) presented high-frequency MSI (MSI-H). Of the 8 MSI-H patients, 5 presented hMLH1 methylation, whereas no low-frequency MSI (MSI-L) and microsatellite stable (MSS) cases exhibited hMLH1 methylation (5/8 vs. 0/43, p < 0.00001). Furthermore, these patients also presented E-cadherin and p16 hypermethylation. Our data showed a significant correlation between hMLH1 methylation and MSI in GC, and suggested that a common mechanism of aberrant de novo methylation can be postulated in these cancers.

Distinct methylation pattern and microsatellite instability in sporadic gastric cancer

Aberrant 5' CpG island methylation is an alternative mechanism of gene inactivation during the development of cancer as demonstrated for several tumor-suppressor genes. Also, marked relationship of microsatellite instability (MSI) and DNA methylation has been reported in sporadic colorectal cancer, which is a result of epigenetic inactivation of hMLH1 in association of promoter hypermethylation. In the present study, we investigated the 5' CpG island hypermethylation of hMLH1, E-cadherin and p16 in 61 primary gastric cancers (GCs) by using combined bisulfite restriction analysis (COBRA) and methylation-specific PCR (MSP), and their MSI status. Of 61 GCs investigated, 5 (8.1%) tumors presented hMLH1 methylation, 16 (26.2%) and 25 (40.9%) showed E-cadherin and p16 methylation respectively, and 8 (13.1%) presented high-frequency MSI (MSI-H). Of the 8 MSI-H patients, 5 presented hMLH1 methylation, whereas no low-frequency MSI (MSI-L) and microsatellite stable (MSS) cases exhibited hMLH1 methylation (5/8 vs. 0/43, p < 0.00001). Furthermore, these patients also presented E-cadherin and p16 hypermethylation. Our data showed a significant correlation between hMLH1 methylation and MSI in GC, and suggested that a common mechanism of aberrant de novo methylation can be postulated in these cancers.

[Application of measuring 99mTc-MAG3 plasma clearance based on one-compartment model (MPC method) to renal transplantation]

Measurement of 99mTc-MAG3 plasma clearance (CLmag) based on one-compartment model (MPC method) was applied to renal transplantation and evaluated for the factors which might affect the calculated results, especially concerning renal depth. Correlation coefficient of CLmag between MPC method using real renal depth and Russell or Bubeck single sampling method was good (r = 0.852 or 0.876, respectively). Regression equation between MPC method and Russell method was y = 1.044x - 3.0 and was more closer to y = x than that between MPC method and Bubeck method. CLmag of MPC method calculated by estimated renal depth from the abdominal thickness was also similar to that by real renal depth. Even if the fixed renal depth, 4 cm, was applied, the coefficient and regression equation between MPC method and Russell method were r = 0.884 and y = 1.004x - 10.2. In conclusion, MPC method is applicable to the evaluation of renal transplants. Though measuring renal depth is best, calculation with fixed renal depth of 4 cm might be practically acceptable.

Familial gastric cancer in the Japanese population is frequently located at the cardiac region

The clinical features of familial gastric cancer are still unknown. To approach this question, we investigated the clinicopathological characteristics of 16 cases of familial gastric cancer. In this study the criteria used to define familial gastric cancer was the existence of three or more family members with gastric cancer in at least two successive generations. The clinicopathological characteristics of cases who fulfilled this criteria were studied. This study contained 16 familial gastric cancer probands. Seven cases (44%) of gastric cancer had developed at the cardiac region of the stomach. This frequency was significantly higher than for gastric cancer in the general population in Japan (15.4%, p < 0.01). Undifferentiated types were dominant in familial gastric cancer (69%, p < 0.05). Furthermore, the frequency of disseminated peritoneal (40%) and liver metastases (20%) in familial gastric cancer was also significantly higher than for gastric cancer in the general population in Japan (10.9%, p < 0.01, and 4.4%, p < 0.05, respectively). Familial gastric cancers were frequently located at the cardiac region and appeared to be more aggressive than sporadic gastric cancers. The unique characteristics of familial gastric cancer suggest a genetic background in their etiology.

Alpha1-antitrypsin deficiency and toxic shock: a Japanese autopsy case

A 74-year-old Japanese female presented with the sudden appearance of hemorrhagic purpuric ecchymoses on her lower extremities and with fever and chills, and died on the fifth day of hospitalization. A diagnosis of alpha1-antitrypsin (AT) deficiency was made postmortem. The liver weighed 1260 g. Histological sections from the liver revealed rather severe fatty changes of the hepatocytic parenchyma and partial loss of the normal hepatic architecture with fibrosis. The hepatocytes contained periodic acid-Schiff (PAS)-positive, diastase-resistant and alpha1-AT-positive intracytoplasmic globules. There was markedly increased inflammatory infiltration with severe edema and congestion, accompanied by fibrous, thickened pulmonary alveolar walls with fibrin deposition in the lungs (right, 410 g; left, 280 g), which suggest findings similar to those seen in multiple organ failure. Mild pulmonary emphysema was also present in the upper lobes of the lungs. Histological sections from the hemorrhagic necrotic ecchymoses of the skin showed marked neutrophil infiltration over the subcutaneous tissue with bleeding and blistering. A finding of thrombophlebitis was also found in the subcutaneous tissue. No bacteria were detected in the ecchymoses, the urine or the blood. Plasma protein analysis revealed a lower level (9.5 micromol/L) of alpha1-AT and a higher level (330 U) of anti-streptolysin O (ASO). These findings suggest that the patient died of toxic shock-like syndrome and that alpha1-AT deficiency might have facilitated the development of the toxic shock. To our knowledge, this is the first case of toxic shock associated with alpha1-AT deficiency.

Expression and identification of aberrant c-kit transcripts in human cancer cells

We have previously cloned and sequenced a novel 3.5 kb c-kit mRNA expressed in a colon carcinoma cell line Colo201. Here we examined the expression of this truncated form of c-kit in 14 gastrointestinal cancer cells and 16 hematopoieic cancer cells by RT-PCR. Expression of the aberrant c-kit transcript was observed in various cancer cell lines. Furthermore, a new transcript which is 78 bp shorter than the transcript previously described was identified and characterized. These results indicate that two kinds of aberrant c-kit transcript produced by alternative promoter in intron 15 are expressed in human cancer cells.

Infrequent alterations of the p16 (MTS-1) gene in human gastric cancer

p16 (MTS-1, multiple tumor suppressor gene 1), a putative tumor suppressor gene, is one of the cyclin-dependent kinase inhibitors (CDI) and it regulates the G1/S transition of the cell cycle. To clarify the role of p16 in primary gastric cancer, we have investigated somatic mutations of this gene by using the polymerase chain reaction/single strand conformation polymorphism (PCR-SSCP) method. In 23 surgical specimens of primary gastric cancer, none were detected in exon1 and exon 2. Among the 6 human gastric cancer cell lines examined, PCR products were not found in 2, MKN28 and MKN45, suggesting the presence of homozygous deletions. No mutation was found in the other 4 cell lines. Furthermore, decreased expression levels were not observed in 13 gastric cancer tissues by reverse transcription PCR (RT-PCR). Considering the above results of PCR-SSCP and RT-PCR, genetic alterations of the p16 gene are rarely implicated in human gastric cancer tumorigenesis.

Genetic alterations in rat colon tumors induced by heterocyclic amines

BACKGROUND

In rat colon tumors induced by the cooked food mutagens 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) and 2-amino-3-methylimidazo[4,5-f]quinoline (IQ), ras and p53 alterations are rarely detected. To investigate the roles of the APC gene and microsatellite instability (MI) in PhIP-induced colon carcinogenesis, mutations of the APC gene and alterations of microsatellites were examined.

METHODS

Complimentary DNA sequence of the rat APC gene were determined by polymerase chain reaction (PCR) using primers based on the human APC sequence. PCR-single strand conformation polymorphism (SSCP) analysis was performed using primers based on sequences of flanking introns and exon 15. Microsatellite alterations were also analyzed using 85 microsatellite sequences dispersed through most of the rat chromosomes.

RESULTS

Five mutations in the APC gene were detected in four of eight PhIP-induced rat colon tumors. All five mutations involved deletion of a guanine base in a 5'-GGGA-3' sequence. Only 2 of 13 IQ-induced colon tumors had mutations of the APC gene and these were base substitution mutations. Seven of eight PhIP-induced colon tumors had microsatellite alterations in at least one locus, whereas no alterations were observed in the IQ-induced colon tumors.

CONCLUSIONS

The specific 5'-GGGA-3' to 5'-GGA-3' mutation and MI demonstrated in this study are strong evidence of a mutational fingerprint of PhIP.

APC gene mutations in human prostate cancer

Prostate cancer is the most common cancer in aged men. Although ras and p53 gene mutations have been detected in some prostate cancers, the major genetic alterations involved in its carcinogenesis are not well understood. Mutation of the APC gene is responsible for colorectal tumors in which ras and p53 mutations are also often involved. Using PCR-SSCP analysis and sequencing, we examined 31 human primary prostate cancers (three cases at stage A, 10 at stage B, five at stage C and 13 at stage D) and four cases of lymph node metastasis from the stage D cases, for mutations in the APC gene. A mutation was detected in only one of the 35 samples (3%). This mutation, present in a primary stage B cancer, had a T to C transition in exon 15 at the first position of codon 956, resulting in substitution of histidine for tyrosine. This study clarified that APC gene mutations are not largely involved in the development of clinical prostate cancer.

Does an allergy skin test on school-children predict respiratory symptoms in adulthood?

BACKGROUND

It is interesting from the correct point of preventive health care whether allergy skin tests at entry have the positive relationship with common respiratory symptoms such as persistent cough, persistent phlegm and wheeze with colds at end point in longitudinal studies.

OBJECTIVE

The purpose of this study is to investigate this relationship in subjects followed from when they were school-children until they were young adults.

METHODS

Young adults aged 18-31 years who had participated in an allergy skin test and a health survey for common respiratory symptoms during primary and junior high school were asked about their respiratory symptoms at the end-point in the follow-up study. Three cohort groups were employed in the follow-up study.

RESULTS

According to a multiple logistic analysis with adjustments made for sex, symptoms at entry in childhood, and age and smoking habits at the end-point, young adults with a positive skin test to an extract of house dust as school-children showed a higher prevalence of wheeze with colds compared with those with a negative skin test. However, this relationship was not found for persistent cough or persistent phlegm, indeed, the latter symptom was significantly associated with negative skin tests in one cohort group.

CONCLUSION

The respective symptoms at entry in childhood were also predictors of their occurrence in young adults. The results show that the common respiratory symptoms such as persistent phlegm and wheeze with colds in childhood are related to those in young adults rather than is an allergy skin test to an extract of house dust in childhood.

[Study of atherosclerosis regression in the elderly--central depression and its correlation to ulcerated plaques]

Atherosclerotic plaque with central depression (depressed lesion) was firstly proposed in our previous report as one of the morphological features of regressed lesions, which was characterized by the presence of isolated, well defined lesions with a centrally depressed area and smooth surface. They were obviously different from atherosclerotic plaques with ulceration (ulcerated plaques) in elderly autopsy cases. In this study, 30 ulcerated plaques obtained from specimens of the elderly aortas were histologically and immunohistochemically investigated to clarify the morphogenesis of the depressed lesion and its correlation to the ulcerated plaque. These depressed lesions were divided into 4 groups according to their derivation; (a) fused lesion of multiple fibrous plaques, (b) regressing lesion of plaques, (c) healed ulcerated plaques, and (d) mixed type of these lesions. Regeneration of endothelial cell was noted in the peripheral zone of ulcerated plaques, and collagen type IV was also increased in the stroma of these ulcerated plaques. These were healed ulcerated plaques. The ulcerated plaques with complete restoration of endothelial cells on the ulcerated surface may become atherosclerotic plaques with central depression. These lesions are one of the histological features of regression in advanced atherosclerosis.

[Detection of cortical infarcts in brain MR imaging: feasibility of short-TR-T2-weighted imaging using a fast spin echo sequence]

MRI of the brain using a fast SE sequence is often performed with a TR above 5000 msec, so there is a tendency for the signal of CSF to become too high. However, when cerebral atrophy is marked, small lesions of the brain parenchyma can be hard to detect. Therefore, we examined short-TR-T2-weighted images using a fast spin echo sequence. The 58 subjects included 33 men and 25 women, and cortical infarction was detected in five of them. On the short-TR-T2WI sequences, the infarct lesions were imaged as areas of higher signal intensity than cerebrospinal fluid, the signal of which was reduced. In cortical infarction cases, fluid-attenuated inversion recovery (FLAIR) images can detect the lesion more easily, but FLAIR sequences cannot be obtained with all MR equipment. Short-TR-T2WI, which readily yields images comparable to those of FLAIR, is an useful method.

Specific 5'-GGGA-3'-->5'-GGA-3' mutation of the Apc gene in rat colon tumors induced by 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine

The APC gene plays a major role in human colon carcinogenesis. We determined the genomic structure of the rat Apc gene, and we analyzed mutations in colon tumors induced in F344 rats by 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) and 2-amino-3-methylimidazo[4,5-f]quinoline (IQ), potent carcinogens contained in ordinary daily human food. Of eight PhIP-induced tumors, one tumor had two Apc mutations, two tumors had a mutation with loss of the normal allele, and one had a mutation. Two of the above five mutations were at nucleotide 1903, one at 2605, and two at 4237, all being a deletion of a guanine base at the 5'-GGGA-3' site and resulting in truncation of the APC protein. Of 13 IQ-induced tumors, 2 had an Apc mutation with loss of the normal allele. The two mutations were a missense mutation (T-->C) at nucleotide 1567 and a nonsense mutation (C-->T) at 2761. Alteration of the Apc gene was shown to play a more important role in PhIP-induced than in IQ-induced rat colon carcinogenesis. PhIP-induced tumors are characterized by their specific and unique mutation, which may be useful for mutational fingerprinting of human cancers.

p53 gene mutations in human prostate cancers in Japan: different mutation spectra between Japan and western countries

The involvement of p53 mutations in prostate cancers in Japan was investigated. To evaluate any possible clinicopathological significance, p53 mutations in 40 samples from 36 Japanese prostate cancers of different stages (five cases of latent tumors, three of stage A cancers, 10 of stage B, five of stage C and 13 of stage D), including four lymph node metastases of stage D cases, were examined by polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) analysis and sequencing. Mutations were detected in five of 40 samples (12.5%); four were in primary cancers and the other in a lymph node metastasis from one of them. All mutation-positive cases were in stage D, and the mutation frequency in stage D cases was 31%. This result indicates that p53 mutations may play a role in the progression of a subgroup of prostate cancers in Japanese, as observed for Americans and Europeans. However, a difference was noted between Japanese and Americans in the p53 mutational spectrum (at CpG site), presumably arising from variation in the underlying etiologic factors.

Expression of MUC1 on myeloma cells and induction of HLA-unrestricted CTL against MUC1 from a multiple myeloma patient

Polymorphic epithelial mucin (MUC1) was detected in myeloma cells and in sera of multiple myeloma patients. HLA-unrestricted CTL that recognize tumor-associated epitopes on MUC1 has been shown to be induced from breast and pancreas cancer patients. To investigate whether such CTL can also be induced from multiple myeloma patients, an allogeneic mixed leukocyte tumor cell culture was performed. PBMCs of a multiple myeloma patient were stimulated by different allogeneic breast carcinoma and myeloma cell lines. The cultured PBMCs were proliferated and a CTL line TN was established. TN exclusively expressed TCR-alpha/beta, CD3, and CD8. TN lysed breast carcinoma and myeloma cell lines but did not lyse K562, which is sensitive to NK cells. The cytotoxicity of TN was inhibited by anti-CD3 Abs but not by anti-HLA Abs. Thus, the TCR-alpha/beta was considered to be involved in the recognition of the target cells but HLA was not. Furthermore, TN lysed transformed mouse fibroblast cells transfected with MUC1 cDNA, suggesting that this CTL line recognizes MUC1 directly. Thus, it is concluded that precursors of HLA-unrestricted and anti-MUC1 reactive CTL could exist in the peripheral blood of multiple myeloma patients and that myeloma cells can express epitopes on MUC1, which can be recognized by the CTL.

Expression of MUC1 on myeloma cells and induction of HLA-unrestricted CTL against MUC1 from a multiple myeloma patient

Polymorphic epithelial mucin (MUC1) was detected in myeloma cells and in sera of multiple myeloma patients. HLA-unrestricted CTL that recognize tumor-associated epitopes on MUC1 has been shown to be induced from breast and pancreas cancer patients. To investigate whether such CTL can also be induced from multiple myeloma patients, an allogeneic mixed leukocyte tumor cell culture was performed. PBMCs of a multiple myeloma patient were stimulated by different allogeneic breast carcinoma and myeloma cell lines. The cultured PBMCs were proliferated and a CTL line TN was established. TN exclusively expressed TCR-alpha/beta, CD3, and CD8. TN lysed breast carcinoma and myeloma cell lines but did not lyse K562, which is sensitive to NK cells. The cytotoxicity of TN was inhibited by anti-CD3 Abs but not by anti-HLA Abs. Thus, the TCR-alpha/beta was considered to be involved in the recognition of the target cells but HLA was not. Furthermore, TN lysed transformed mouse fibroblast cells transfected with MUC1 cDNA, suggesting that this CTL line recognizes MUC1 directly. Thus, it is concluded that precursors of HLA-unrestricted and anti-MUC1 reactive CTL could exist in the peripheral blood of multiple myeloma patients and that myeloma cells can express epitopes on MUC1, which can be recognized by the CTL.

Absence of p53 mutations in rat colon tumors induced by 2-amino-6-methyldipyrido[1,2-a:3',2'-d]imidazole, 2-amino-3-methylimidazo[4,5-f]quinoline, or 2-amino-1-methyl-6-phenylimidazo]4,5-b]pyridine

Colon tumors were induced in F344 rats by three heterocyclic amines (HCAs), 2-amino-6-methyl-dipyrido[1,2-a:3',2'-d]imidazole (Glu-P-1), 2-amino-3-methylimidazo[4,5-f]quinoline (IQ) or 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP), and examined for p53 mutations. Seven carcinomas induced by Glu-P-1, and nine carcinomas and two adenomas induced by IQ were examined by cDNA-polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) analysis from codon 103 to 391 of p53, which encompasses the conserved regions II to IV. Nine carcinomas induced by PhIP were examined by genomic PCR-SSCP analysis of exons 5 to 7 (from codon 124 to 304), which encompasses the 3' half of the conserved region II and all the conserved regions III-V. No band shifts were found in any of these tumors under at least two conditions of SSCP analysis. Our previous study had shown a Ki-ras mutation in only one Glu-P-1-induced adenocarcinoma among the same 27 colon tumors, and no other mutation of ras family genes had been found. HCA-induced rat colon tumors appear to represent a group of human colon tumors in which neither Ki-ras nor p53 is involved.

Infrequent mutation of Ha-ras and p53 in rat mammary carcinomas induced by 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine

2-Amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) is the most abundant of the heterocyclic amines, a group of potent carcinogens contained in cooked meat and fish. Female F344 rats fed a diet containing 100 or 400 ppm PhIP developed mammary carcinomas within 104 or 52 wk, respectively, at the rate of 47% for each group; these carcinomas were examined for mutations in three members of the ras gene family and in the p53 gene. Single-strand conformation polymorphism (SSCP) analysis and direct sequencing demonstrated a G-->A transition at the second position of Ha-ras codon 12, with the resultant substitution of glutamic acid for glycine, in two of 10 carcinomas induced by 100 ppm PhIP and in one of seven induced by the 400 ppm dose. No mutations in Ki-ras or N-ras were detected. cDNA polymerase chain reaction-SSCP analysis and direct sequencing demonstrated a G-->T transversion at the third position of p53 codon 130, with the resultant substitution of asparagine for lysine, in one of the 10 carcinomas induced by 100 ppm of PhIP for which freshly frozen samples were available. PhIP-induced rat mammary carcinogenesis can be regarded as a unique system in that rat mammary carcinomas are negative for ras and p53 mutations.

Detection of Haemophilus influenzae in middle ear of otitis media with effusion by polymerase chain reaction

Otitis media with effusion (OME) is one of the major causes of hearing loss in childhood. The pathogenesis still remains unclear, though it is closely related to acute otitis media with bacterial infections. It is known that Haemophilus influenzae is one of the most common bacteria isolated from middle ear effusions (MEEs). Recently, in vitro DNA amplification by polymerase chain reaction (PCR) is a new technology that has considerable implication for diagnosis of viral and bacterial infections because of its potentially precise specificity and sensitivity. In the present experiment polymerase chain reaction (PCR) was applied to the detection of DNA genome of H. influenzae contained in middle ear effusions. By Southern blot hybridization, two characteristic bands for H. influenzae DNA were detected at 273 b.p. and 550 b.p. position in 15 of 27 MEEs. However, no organism was cultured by conventional methods. Our results indicate the PCR technique is more specific and sensitive in detection of bacteria in middle ear effusion of OME, compared with conventional methods. It strongly suggests more involvement of the bacteria, especially H. influenzae, in OME onset.

[Respiratory symptoms in young adulthood in relation to the results of a house dust skin test during childhood--a 20 year follow-up survey]

Beginning in 1972, a survey of respiratory symptoms and allergic skin tests in school children from an agricultural area in the Hokuriku region has been continuing. A higher prevalence of respiratory symptoms in school children with positive house dust skin test has been previously reported. In order to elucidate the relationship between results of a house dust skin test during childhood and manifestation of respiratory symptoms thereafter, an examination of respiratory symptoms was conducted in 1991, of the portion of the 5,334 subjects who participated in the earlier survey during childhood, who still live in the same town after leaving junior high school. The results are as follows: 1) During childhood (school-age), prevalence of respiratory symptoms (subacute cough, wheezing when having a cold, wheezing attack) was higher in the positive skin test group (612 subjects) compared to the negative group (856 subjects). There were no significant differences between the two groups in the prevalence of respiratory symptoms (subacute phlegm, wheezing when not having a cold). 2) In young adulthood, prevalence of respiratory symptoms (subacute cough, subacute phlegm) was higher in the negative skin test group compared to the positive group. There were no significant differences between the two groups in the prevalence of respiratory symptoms (wheezing when not having a cold, wheezing attack). The prevalence of wheezing when having a cold was higher in the positive group compared to the negative group. 3) The paradoxical results in young adulthood was due to a marked decline in the prevalence ratio of the high positive rate skin test group (184 subjects) to the negative skin test group. This suggested a decline in contribution of serum IgE to manifestation of respiratory symptoms in young adulthood compared to childhood, with the result that the positive skin test group had a higher prevalence of respiratory symptoms during childhood, but lower in young adulthood.

Rare frequency of activation of the Ki-ras gene in rat colon tumors induced by heterocyclic amines: possible alternative mechanisms of human colon carcinogenesis

Heterocyclic amines present in cooked foods are known to produce colon tumors in F344 rats at a high incidence, indicating the possibility of involvement of ras gene activation in colon carcinogenesis in rats as in humans. We examined mutations at codons 12, 13, and 61 of the Ki-ras, Ha-ras, and N-ras genes by polymerase chain reaction--direct sequencing in seven colon tumors in F344 rats induced by 2-amino-6-methyldipyrido-[1,2-a:3',2'-d]imidazole (Glu-P-1), 11 induced by 2-amino-3-methylimidazo[4,5-f]quinoline, and nine induced by 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine. A Ki-ras gene mutation (G-->T at the second position in codon 12) was found in one Glu-P-1-induced colon adenocarcinoma. None of the other 26 tumors had mutations in any of these three ras family genes. These results indicate that in rats, colon carcinogenesis induced by heterocyclic amines may be induced by alterations of other oncogenes or tumor suppressor genes. We think this experimental system using carcinogens to which humans are exposed is a good model for studying alterations of other genes in human colon tumors in which no Ki-ras alterations are observed.

Interleukin-1 of cholesteatomatous keratinocytes

Interleukin-1 (IL-1) has been thought to be one of the essential cytokines mainly produced by macrophages. It has recently been reported that epidermal keratinocytes produce IL-1, and attention is being paid to local immune reactions mediated with this cytokine. Interleukin-1 not only activates lymphocytes, but also acts as an osteoclast-activating factor. In this study, we used immunohistochemistry and immunoblotting on cholesteatomatous epithelium with anti-IL-1 alpha antibody and anti-IL-1 beta antibody. Next, the relationship of cholesteatomatous debris to the production of IL-1 by keratinocytes was evaluated. Highly concentrated IL-1 alpha was found in the cholesteatomatous epithelium, especially in the basal cell layer. The intensity of IL-1 beta staining was weaker than that of IL-1 alpha staining. In the immunoblotting study, the 31 kd band, an intracellular immature precursor molecule, was identified. The production of IL-1 alpha from keratinocytes was augmented to a greater degree by cholesteatomatous debris than by lipopolysaccharide or keratin. The keratinocytes did not produce IL-1 beta. These findings suggest that IL-1 alpha is derived from cholesteatomatous keratinocytes. Interleukin-1, mainly IL-1 alpha, from the stimulated cholesteatomatous keratinocytes may be an important factor in the markedly increased bone resorption observed in cholesteatoma.

Circulating tumor-associated antigens detected by monoclonal antibodies against the polypeptide core of mucin--comparison of antigen MUSE11 with CA15-3

The antigen MUSE11 detected by a monoclonal antibody (MAb) is an adenocarcinoma-associated antigen, while CA15-3 is a representative breast cancer-associated antigen detected by MAbs 115D8 and DF3. MAb MUSE11 showed higher binding activity to a synthetic peptide corresponding to the tandem repeat motif of the mucin core protein than that of MAb DF3, although MAb DF3 also had a significant binding activity indicating that MAbs MUSE11 and DF3 could recognize an identical polypeptide core. The reactivity of MAb DF3 to a breast cancer cell line MRK-neu-1 was completely abolished by neuraminidase treatment whereas that of MAb MUSE11 was partly conserved. The simultaneous measurement of the antigens MUSE11 and CA15-3 in sera from 35 cancer patients demonstrated that the incidence of abnormal serum level of CA15-3 was lower than that of antigen MUSE11. These data suggest that at least a part of the structural basis for the difference between the serum levels of antigen MUSE11 and CA15-3 could be carbohydrate side chains including sialic acids.

[The localization and production of interleukin-1 in pharyngeal epithelium]

Interleukin-1 (IL-1) has been thought to be one of the essential cytokines mainly produced by macrophage. The function of IL-1 are not only activates T-lymphocytes, but also regulates immune responses to several antigens and effects on local and systemic immune reactions. Recently, it is reported that epidermal keratinocytes produces IL-1, and attention has been paid to local immune reaction mediated with this cytokine. In this study, we performed immunohistochemistry and immunoblotting on the pharyngeal epithelial keratinocytes and we evaluated the production of IL-1 by these cells. Pharyngeal mucous membrane of each region reacted strongly against anti-IL-1 alpha antibody, on the contrary, anti-IL-1 beta antibody comparatively only weakly. Strong reactivity was often observed on the basal layer, then it was seemed that some important relationship exists between the production of IL-1 and maturation of pharyngeal keratinocytes. Infiltration of T-lymphocytes was observed in proportion to the increase of epithelial reactivity against IL-1. There seemed to be no correlation between expression of HLA-DR antigen on keratinocytes and reactivity of IL-1. In immunoblotting study, the 31kD band, intracellular immature molecule, was identified besides 17 and 52kD. From this finding, it was suggested that IL-1 is derived from pharyngeal keratinocytes. In conclusion, the present study is helpful for well-understanding of local cellular immunity of pharyngeal mucous membrane.

Recognition of the polypeptide core of mucin by monoclonal antibody MUSE11 against an adenocarcinoma-associated antigen

Monoclonal antibody (MAb) MUSE11 detects an adenocarcinoma-associated antigen and is useful for the serodiagnosis of pancreas cancer. We established a sandwich enzyme immunoassay using MAb MUSE11 and MAb DF3 against a breast cancer-associated mucin core protein as a catcher and a tracer, respectively. With this assay system, the binding of the tracer MAb DF3 to an antigen in the human kidney tissue lysate was clearly inhibited by MAb MUSE11. In addition, MAb MUSE11 showed a significant binding activity to the synthetic peptide corresponding to the tandem repeat of a human epithelial mucin core protein. These data suggest that MAb MUSE11 could detect the polypeptide core of a mucin, and may be of use for studying mucin as a gene product.