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T Tajiri

Publications and source records attributed to T Tajiri.

At least 73 records · Page 4Linked to original sources
PubMed1999

Highly sensitive analysis for N-myc amplification in neuroblastoma based on fluorescence in situ hybridization.

BACKGROUND/PURPOSE: The N-myc amplification status in neuroblastoma has been evaluated previously for the whole tumor by the Southern blot method. The aim of this study is to evaluate the effectiveness of the fluorescence in situ hybridization (FISH) method to analyze N-myc amplification in neuroblastoma and compare the findings with those using the Southern blot method. METHODS: In 26 neuroblastoma primary tumors and metastatic lesions, the N-myc amplification status was evaluated by both the Southern blot method and FISH method. RESULTS: Of the 22 samples with no N-myc amplification using Southern blot, no cells with N-myc amplification using FISH were present in 21 of the samples. However, one metastatic liver lesion showed 16% of the nuclei to display more than 10 copies of N-myc based on FISH analysis. In the 4 remaining samples with N-myc amplification using the Southern blot method (17 copies, 15 copies, 6 copies, and 3 copies), the rates of cells with more than 10 copies of N-myc based on a FISH analysis were 79%, 68%, 94%, and 9%, respectively. CONCLUSIONS: The FISH method can detect more accurately N-myc amplification than the Southern blot method either when the rate of cells with N-myc amplification is low or intratumor heterogeneity is present.

Blotting, Southern↗
PubMed1999

Rapid somatic growth after birth in children with neuroblastoma: A survey of 1718 patients with childhood cancer in Kyushu-Okinawa district.

OBJECTIVE: To evaluate the association of somatic growth from birth through diagnosis with the development of childhood cancer. METHODS: The weights and heights of 1718 children with cancers were determined and converted into standard deviation (SD) scores, both at birth and at diagnosis, by using the means and SD values of the general population. RESULTS: Among patients with neuroblastoma and acute lymphoblastic leukemia, the percentages of children with body weight and height over mean + 2 SDs were significantly higher at diagnosis than the expected value in the general population. The percentage of children with neuroblastoma and body weight over mean + 2 SD increased significantly from birth through diagnosis (P =.04). Although the medians of weight SD scores decreased from birth through diagnosis in patients with representative cancers except for neuroblastoma, the value significantly increased in patients with neuroblastoma diagnosed before 1 year of age (P =.03), especially in those whose cancer was detected by mass screening at 6 months of age (P <.01). CONCLUSIONS: Rapid somatic growth from birth through diagnosis in patients with neuroblastoma diagnosed before 1 year of age suggests a possible involvement of certain growth factors in these patients.

Birth Weight↗
PubMed1999

Lung cancer in a child with a substantial family history of cancer.

The occurrence of primary lung cancer is rare in childhood. The case of an 11-year-old boy with primary lung cancer is presented in this report. He had a substantial family history of cancer. His chief complaint was coughing with right chest pain. A chest radiograph showed a coin lesion in the right lower lung. A right lower lobectomy revealed a squamous cell carcinoma (stage IIIA at Japanese TNM classification). Systemic chemotherapy using cisplatin, vindesine, THP-adriamycin and cyclophosphamide was performed. Six months after surgery, a recurrent tumor occurred. An analysis of the familial cancer related genes (p53 gene and mismatch repair gene) showed no abnormality.

Age of Onset↗
PubMed1999

PTEN/MMAC1 mutations in hepatocellular carcinomas: somatic inactivation of both alleles in tumors.

Allelic loss of loci on chromosome 10q occurs frequently in hepatocellular carcinomas. Somatic mutations of the PTEN/MMAC1 gene on this chromosome at 10q23 were recently identified in sporadic cancers of the uterus, brain, prostate and breast. To investigate the potential role of PTEN/MMAC1 gene in the genesis of hepatocellular carcinomas, we examined 96 tumors for allelic loss on 10q and also for subtle mutations anywhere within the coding region of PTEN/MMAC1 gene. Allelic loss was identified in 25 of the 89 (27%) tumors that were informative for polymorphic markers in the region. Somatic mutations were identified in five of those tumors: three frameshift mutations, a 1-bp insertion at codon 83-84 in exon 4 and two 4-bp deletions, both at codon 318-319 in exon 8; two C-to-G transversion mutation, both at -9 bp from the initiation codon in the 5' non-coding region of exon 1. No missense mutation was observed in this panel of tumors. In most of the informative tumors carrying intragenic mutations of one allele, we were able to detect loss of heterozygosity as well. These findings suggest that two alleles of the PTEN/MMAC1 gene may be inactivated by a combination of intragenic point mutation on one allele and loss of chromosomal material on the other allele in some of these tumors.

Alleles↗
PubMed1998

A microsatellite instability analysis in neuroblastoma based on a high resolution fluorescent microsatellite analysis.

It has recently been reported that mismatch repair enzymes, which are one type of DNA repair enzymes, are the causative genes for a major group of hereditary non-polyposis colon cancers (HNPCC). Abnormalities in the mismatch repair system can be monitored by observing instability at the microsatellite loci (MSI) in cancer cells. MSI has been reported not only in tumors associated with hereditary non-polyposis colorectal cancer but also in sporadic forms of various tumors. No correlation between pediatric malignant tumors and the mismatch repair system has yet been reported. In the present study, we examined the frequency of MSI in 21 neuroblastomas, which are the most common solid tumors in childhood, using a high resolution fluorescent microsatellite analysis. MSI on five microsatellite loci was detected in none of the 21 samples. Other mechanisms independent of mismatch repair deficiency may thus play a role in both tumorigenesis and the development of neuroblastoma.

Child↗
PubMed1998

Mass screening for neuroblastoma at 6 months of age: difficult to justify.

BACKGROUND/PURPOSE: A statistical analysis of the mass screening for neuroblastoma in Japan based on a population study rarely has been reported. This study aims to evaluate retrospectively the effectiveness of mass screening at 6 months of age using the available population data. METHODS: The data on the neuroblastoma cases registered by the Committee for Pediatric Solid Malignant Tumors in the Kyushu area were analyzed based on both screened and unscreened populations in the Kyushu area. RESULTS: From 1988 to 1992, the cumulative incidence of neuroblastoma in children less than 5 years of age was 82 in 484,599 for screened children, and 11 in 92,966 for unscreened children, respectively. Fourteen of the 82 screened patients had negative findings at 6 months of age (MS-negative cases). No significant difference was observed in the cumulative mortality rates from neuroblastoma in children younger than 5 years of age between the screened children and the unscreened children. Six of seven patients who died among the screened children were MS-negative cases with stage III or IV disease. In addition, no significant difference was found in the cumulative mortality rates from the neuroblastoma cases in patients less than 5 years of age between the children screened from 1988 to 1992 (7 of 484,599) and all children from 1980 to 1984 (14 of 668,084). CONCLUSIONS: These findings suggests that the majority of the patients detected by mass screening had a favorable prognosis, and, mass screening in Japan for children less than 6 months of age was not observed to reduce the incidence and mortality from neuroblastoma. Therefore, mass screening at 6 months of age was not found to improve substantially the prognosis of patients with unfavorable neuroblastoma identified over 1 year of age, which is the primary purpose of such mass screening for neuroblastoma.

Evaluation Studies as Topic↗
PubMed1998

Clinicopathological studies on association of gallbladder carcinoma and pancreaticobiliary maljunction.

During the past 17 years, 1,722 of 4,832 consecutive patients investigated with endoscopic retrograde cholangiopancreatography (ERCP) were assessed by the radiological criteria of the Japanese Study Group of Pancreaticobiliary Maljunction (PBM). Out of these 1,722 patients, PBM was found in a total of 52, representing 3.0%, of which gallbladder carcinoma was associated with 14. These 14 with gallbladder carcinoma consisted of 10 (62.5%) of the 16 with PBM without association of congenital bile duct dilatation (CBDD) and 4 (11.1%) of the 36 PBM with CBDD. The relationship between PBM and gallbladder carcinoma was closely examined; PBM was noted in 14 (32.6%) of a total of 43 patients with gallbladder carcinoma compared to 38 (2.3%) among the 1,679 patients with various diseases excluding gallbladder carcinoma. Similarly, it was revealed that gallbladder carcinoma was predominantly noted in the 14 (26.5%) of the 52 patients with PBM in contrast to an incidence of 1.7% (29) among the 1,670 patients without PBM. As we studied the characteristic clinical features of the 14 gallbladder carcinoma patients with PBM when compared with 29 of those without PBM, the following was disclosed: on average, the patients with PBM were 10 years younger (49.4 vs 61.4 years in mean age); there was a preponderance of women (0/14 vs 12/17, male-female ratio); there existed a significantly lower incidence of associated gallstone disease (7.1% vs 72.4%). These figures were shown to be statistically significant. We concluded that the results prove a link between the crucial features of gallbladder carcinoma and PBM, and also suggest the promotive role of PBM in carcinogenesis of the gallbladder.

Adenocarcinoma↗
PubMed1997

Hepatic lobar differences in progression of chronic liver disease: correlation of asialoglycoprotein scintigraphy and hepatic functional reserve.

We studied the hepatic functional reserve in the lobes of the liver in 28 patients with chronic liver disease and 13 controls using single photon emission computed tomography (SPECT) imaging with a radiolabeled asialoglycoprotein analog, Technetium-99m-diethylenetriaminepentaacetic acid-galactosyl-human serum albumin (Tc-99m GSA). Counts of Tc-99m GSA radioactivity in the liver on SPECT images significantly correlated (P < .0001) with the serum albumin level (r = .612), log (serum cholinesterase activity) (r = .618), serum bilirubin level (r = .628), prothrombin time (r = .715), hepaplastin test (r = .637), and indocyanine green retention rate at 15 minutes (r = .771), making it possible to estimate the distribution of functional reserve in the liver based on counts. Using the intact hepatocyte theory, we estimated the number of viable hepatocytes based on the counts. With progression of hepatic functional degeneration, counts per unit hepatic volume decreased (rho = .779, P < .0001), and left lobe to right lobe ratio of this parameter increased (rho = .491, P = .0019) significantly. These findings suggest that the reduction of hepatic functional reserve per unit hepatic volume and numerical density of the hepatocytes, and the proliferation of fibrosis in patients with chronic liver disease is slower in the left lobe than in the right. We discuss a possible biological basis for these apparent lobar differences and for hepatic morphological changes seen in cirrhosis.

Adult↗
PubMed1996

Effect of mutY and mutM/fpg-1 mutations on starvation-associated mutation in Escherichia coli: implications for the role of 7,8-dihydro-8-oxoguanine.

MutY specifies a DNA glycosylase that removes adenines unnaturally paired with various bases including oxidized derivatives of guanine, such as 7,8-dihydro-8-oxoguanine (8-oxoG). The rate of mutation in starved Escherichia coli cells is markedly raised in mutY mutants defective in this glycosylase. As predicted, the mutations produced include G to T transversions. Bacteria carrying mutM or fpg-1 mutations (defective in Fapy glycosylase, which removes oxidized guanine residues such as 8-oxoG) show little or no enhancement of mutation under starvation conditions. When present together with mutY, however, mutM clearly further enhances the rate of mutation in starved cells. Plasmids resulting in overproduction of MutY or Fapy glycosylases reduce the rate of mutation in starved cells. We conclude that, in non-growing bacteria, oxidized guanine residues, including 8-oxoG, constitute an important component of spontaneous mutation. Addition of catalase to the plates did not reduce the mutant yield, indicating that extracellular hydrogen peroxide is not involved in the production of the premutational damage. Singlet oxygen, known to give rise to 8-oxoG, may be the ultimate oxidative species.

Catalase↗
PubMed1996

[The evaluation of therapeutic effect on partial splenic embolization (PSE) for liver cirrhosis patients].

Partial splenic embolization (PSE) was performed on fifty cases with liver cirrhosis underwent no therapy. We evaluated changes of platelet count, ICGR15, GPT and Child-Pugh score which were significantly recovered by PSE. About liver cirrhosis before PSE, K.ICG, GPT, Alb, platelet count and splenic volume were selected as total characteristic factors by principal component analysis. We showed predicting formulas after PSE by multiple regression analysis between five factors selected by principal component analysis and platelet count, HPT, PT, Alb, ICGR15, K.ICG, GOT, GPT and Child-Pugh score after PSE. In conclusion, it is suggested that PSE is useful for recovering of platelet count and liver function. We made it possible to estimate therapeutic effect by predicting formulas before PSE.

Aged↗
PubMed1996

[Mitomycin C-DNA adduct detection in rat organs and human liver].

Mitomycin C-DNA adduct formation was detected in rat organs and also in human tissues by 32P-postlabeling assay. The adduct levels were 1-4 adduct/ 10(8) nucleotides in the human liver after 20 mg of mitomycin C by intra-artery administration and which level was higher comparing with the levels in the rat liver after 10 times more dosages of mitomycin C administration by intra-venous injection. The levels in the human liver were maintained at least 56 days after administration. Organ-specific differences of adduct levels were observed in rat experiments: the adduct levels of liver, lung and kidney were stable but rapidly decreased in stomach and colon. These results, which were obtained from the experiments using the normal parts of each organs may indicate that the drug effectivity for adduct formation was sufficient with smaller dose in the stomach and colon, but disappeared quickly, mean while, the drug effectivity was undergoing in relatively high levels for longer periods in the liver lung and kidney. The analysis of human liver samples may suggest that the selective intra-artery injection induced stronger drug effectivity for adduct formation in human organs.

Adult↗
PubMed1996

[Interventional radiology for portal hypertension. PTO.TIO].

Percutaneous transhepatic obliteration (PTO) and transileocolic vein obliteration (TIO) are techniques of interventional radiology for embolization of collaterals due to portal hypertension 1) We can obtain good results from the precise selection of these techniques in accordance with the patient's hemodynamics and general condition. 2) Endoscopic injection sclerotherapy (EIS) combined with PTO or TIO for esophageal varices proves to be superior in reliability and durability to EIS alone, and the time before retreatment is much longer when this combination therapy is used. 3) In the intractable EIS only cases, a distinct improvement in results and prognosis appears in using PTO or TIO and also in adding more EIS thereafter. 4) After treatment with EIS and PTO or TIO for cardiac varices, we obtain better results in the disappearance rate as well as in the recurrence rate compared with EIS alone. 5) Gastric varices disappear and hepatic encephalopathy due to porto-systemic shunt is improved after PTO or TIO or using these with balloon occluded retrograde transvenous obliteration (BRTO). Thus PTO and TIO would be analogous to surgical devascularization or ligation. Therefore it is concluded that the best results would be obtained with PTO or TIO with other nonsurgical treatments.

Aged↗