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T Shimamoto

Publications and source records attributed to T Shimamoto.

At least 55 records · Page 3Linked to original sources
PubMed2000

[Diffuse large B-cell lymphoma showing CNS invasion by CD30-positive multinuclear giant cells mimicking the clinical features of progressive multifocal leukoencephalopathy].

We report a 55-year-old woman with diffuse large B-cell lymphoma showing central nervous system (CNS) infiltration by CD30-positive lymphoma cells. The patient was admitted with pleural effusion, ascites and a large mass in the abdominal cavity. Southern blot analysis of DNA extracted from the ascites revealed IgJH rearrangement, and therefore she was initially diagnosed as B-cell neoplasia. She received combined chemotherapy (DICE and CHOP regimens), and achieved a transient clinical response. Three months later, she developed various neurological abnormalities, and brain magnetic resonance imaging revealed diffuse infiltration of the cerebral white matter. We considered the possibility of CNS involvement by the lymphoma or progressive multifocal leukoencephalopathy (PML), and began a course of anti-virus therapy and radiation therapy. Because multiple lumbar punctures demonstrated large multinuclear lymphoma cells in the cerebrospinal fluid, a diagnosis of metastatic CNS lymphoma was made. Immunohistochemistry revealed that these lymphoma cells were reactive with anti-CD30 antibody. Although the radiation therapy was temporarily effective against the CNS involvement, the patient died of systemic invasion of the lymphoma cells. The final diagnosis was diffuse large B-cell lymphoma on the basis of pathologic findings, immunohistochemistry, and Southern blot analysis using a mesenteric lymph node obtained at autopsy. Cytospin preparations and immunohistochemistry of specimens obtained from frequent lumbar punctures were useful for differentiating CNS lymphoma from PML.

Brain Neoplasms↗
PubMed1999

Hematopoietic progenitor cell abnormalities in Hoxc-8 null mutant mice.

The mammalian Hox genes encode a family of conserved transcription factors that control the establishment of the body plan during embryogenesis. Many Hox genes are also known to be expressed in hematopoietic cells. We found that Hoxc-8, a member of the Hox C cluster, is expressed in the mouse hematopoietic organs, fetal liver and adult bone marrow. To determine the role of Hoxc-8 gene in hematopoiesis, we compared progenitor cell numbers in the fetal liver and adult bone marrow cells. We observed a significant reduction in the number of erythroid burst-forming unit (BFU-E) and in granulocyte/macrophage colony-forming unit (CFU-GM) in the Hoxc-8 null mice, although the peripheral blood cell counts were normal. The hematopoietic cells from the homozygote animals exhibited normal expansion capability in a liquid culture system, suggesting that the decreased number of progenitor cells may be due to a defect extrinsic to the hematopoietic cells, such as in the interaction with the microenvironment.

Amino Acid Sequence↗
PubMed1999

Trends of cardiovascular risk factors and diseases in Japan: implications for primordial prevention.

We have documented a 70% fall in stroke mortality and a 20% decline in coronary disease (CHD) mortality over the past 30 years in Japan. This parallels a change away from the traditional Japanese eating pattern, with less salt and more meat and dairy products, and decreased rates of smoking. A recent increase in CHD rates among urban Japanese men raises the need for vigorous primordial prevention efforts to avoid elevated blood lipids in modern Japanese populations, while primary prevention efforts must continue for the prevention of hypertension and smoking.

Cardiovascular Diseases↗
PubMed1999

[Cohort study on risk factors for subarachnoid hemorrhage among Japanese men and women].

PURPOSE: To examine the risk factors for subarachnoid hemorrhage, for few prospective data have been available on risk factors of subarachnoid hemorrhage among Japanese. METHODS: A 9.4-year cohort study was conducted on 12,372 men and women, aged 40-69 years, free of history of stroke in six communities in Japan. RESULTS: During the follow-up, seventy-one incidents of subarachnoid hemorrhage occurred. After adjusting for age, serum total cholesterol, body mass index, history of diabetes mellitus, blood pressure category and drinking category, current smokers had a significantly increased risk of subarachnoid hemorrhage compared with 'never-smokers': multivariate relative risk (RR) [95% confidence interval (95% CI)] = 3.1(1.4-6.9) for women, 1.5(0.4-5.3) for men and 2.7(1.3-5.5)for men and women. Hypertensives had a significantly increased risk of subarachnoid hemorrhage compared with normotensives: multivariate RR(95% CI) = 3.1(1.6-6.0) for women, 4.3(1.5-12.0) for men and 3.4(2.0-5.9) for men and women. For men, heavy drinkers (> = 69 g per day ethanol), had a significantly increased risk of subarachnoid hemorrhage compared with 'never-drinkers': multivariate RR(95% CI) = 4.3(1.1-16.8). For women, the relationship between heavy drinking and risk was not examined due to the small number of heavy drinkers (n = 13). Multivariate RR(95% CI) for men who smoked currently and drank heavily compared with men who did not smoke currently nor drink heavily was 6.0(1.8-20.1). Multivariate RR(95% CI) for hypertensive men who drank heavily compared with normotensive or borderline hypertensive men who did not drink heavily was 13.0(3.9-43.9). Multivariate RR(95% CI) for hypertensive men and women who smoked currently compared with normotensive or borderline hypertensive men and women who did not smoke currently was 6.1(1.3-28.7) for men and 6.3(1.4-28.0) for women. Furthermore, the combination of smoking, hypertension and heavy drinking raised the risk of subarachnoid hemorrhage substantially: multivariate RR(95% CI) = 17.5(3.4-90.2). CONCLUSION: Smoking and hypertension appeared to increase the risk of subarachnoid hemorrhage. For men, although the association of smoking with the risk of subarachnoid hemorrhage was weak compared with women, the combination of smoking, hypertension and heavy drinking increased the risk substantially. For women, smoking appeared to be an independent risk of subarachnoid hemorrhage, and the combination of smoking and hypertension increased the risk in additive fashion.

Adult↗
PubMed1999

[The effects of fish supplementation of platelet function, count and metabolism in healthy Japanese].

To investigate changes in platelet function, count and metabolism following fish intake among Japanese, we conducted an experimental intervention study of seven healthy Japanese volunteers (4 males and 3 females) aged 28-58 years. We supplemented their diets with an approximate daily intake of 200-400 g fish which is equivalent to about 10 g n3-polyunsaturated fatty acids (about 3.5 g eicosapentaenoic acid plus 5.0 g docosahexaenoic acid) during the 17 days. The study continued until the 23rd day after returning to an ad libitum diet. The proportion of serum n3-polyunsaturated fatty acids increased two-fold on 5th day and three-fold on 15th day of fish supplementation, but decreased to one and a half-fold on the 2nd day and returned to the level before fish supplementation on the 12th day after returning to an ad libitum diet. The proportion of serum n6-polyunsaturated fatty acids decreased by 17% to the level before fish supplementation on the 5th day, 33% on the 15th day of fish supplementation. However, the decrease was only 10% on the 2nd day and the proportion returned to the same level as before fish supplementation on the 12th day after returning to an ad libitum diet. As a result, the serum n3/n6 polyunsaturated fatty acid ratio increased four-fold on the 15th day of fish supplementation, and returned to the baseline level on the 12th day after returning to an ad libitum diet. Platelet counts decreased and the mean platelet volume increased during fish supplementation. Both parameters returned to the level before fish supplementation on the 12th day after returning to an ad libitum diet. The counts and proportion of large type platelets increased significantly during fish supplementation. Although platelet aggregation by ADP (adenosine 5'-diphosphate) did not change significantly, platelet aggregation by collagen tended to decrease during fish supplementation. Platelet factor 4, one of the indices of platelet activity, decreased significantly during fish supplementation. The mean serum triglyceride level declined during fish supplementation, but returned to the level just before fish supplementation on the 2nd day after returning to an ad libitum diet. The mean plasma fibrinogen level tended to decline during fish supplementation and remained lower until the 12th day after returning to an ad libitum diet. Habitual fish intake may attenuate the development of atherosclerosis and prevent ischemic heart disease through suppression of platelet activity, and by reducing platelet counts and serum triglyceride levels.

Adult↗
PubMed1999

Histopathological factors influencing pelvic lymph node metastases in two or more sites in patients with cervical carcinoma undergoing radical hysterectomy.

BACKGROUND: Lymph node metastasis has been one of the strongest prognostic factors in patients with cervical cancer. In order to select patients with high risk for recurrence, a relationship between status of lymph node and other histopathological parameters was investigated in the patients treated with radical hysterectomy with pelvic lymph adnectomy. METHODS: Of 483 patients undergoing radical hysterectomy with pelvic lymph adnectomy, 309 had stage Ib disease, 62 stage IIa, and 112 stage IIb. RESULTS: Pelvic lymph node metastasis(PLNM) was positive in 98 patients (20%). Of those positive patients, 51(56%) had metastasis in one site, 25 (26%) in two sites, and 22 (22%) in three or more sites. There was a significant difference in survival between patients with metastasis in one or no sites and those in two or more sites (p<0.0001). There was a relationship between PLNM in more than two sites and histological parameters such as histologic subtype, longitudinal diameter of cervical lesion, degree of stromal invasion, depth of stromal invasion, lymph-vascular space invasion, parametrial invasion, and corpus invasion. All of these parameters except for histologic subtype were significantly correlated with the number of positive lymph node sites. Multivariate analysis revealed that among these parameters, longitudinal diameter of the cervical lesion, parametrial invasion, and lymph-vascular space invasion were independently significantly correlated with PLNM in two or more sites. CONCLUSIONS: From these results, patients having these three histopathological parameters could be considered as those with extensive disease distribution.

Adenocarcinoma↗
PubMed1999

DLX-7 homeobox gene regulates c-myc and GATA-1 gene expression in different stages respectively.

Homeobox genes code for transcription factors with a highly conserved DNA binding motif, but their target genes are largely unknown. We have shown that inhibition of the DLX-7 homeobox gene by an antisense oligonucleotide decreased the expression of c-myc and GATA-1 genes. Nuclear run-on assay revealed decreased transcriptional activity of c-myc but not of GATA-1 after DLX-7 antisense treatment. Actinomycin D chase experiments demonstrated that GATA-1 mRNA became unstable as a result of DLX-7 inhibition, whereas c-myc mRNA stability was unaffected. These results suggest that DLX-7 may regulate c-myc and GATA-1 genes at transcriptional and post-transcriptional levels.

Cell Line↗
PubMed1999

[Changes in 24-hour urinary excretion of sodium and potassium in a community-based heath education program on salt reduction].

PURPOSE: To examine changes in urinary excretion of sodium, potassium and sodium/potassium ratio in a community-based health education program on salt reduction. SUBJECTS AND METHODS: The surveyed community was Kyowa town (census population in 1985 = 16,792) where we have conducted a community-based blood pressure control program since 1981 and health education on reduction of salt intake since 1983 for primary prevention of hypertension. A 24-hour urine collection was conducted for systematically selected samples of the participants aged 40-69 in cardiovascular risk surveys in 1982-86 (early period) and in 1990-94 (later period) to estimate changes in urine excretion of sodium, potassium, and sodium/potassium ratio. RESULTS: A 24-hour urine collection was available for 565 persons (410 men and 155 women) in 1982-86 and 1,461 persons (571 men and 890 women) in 1990-94. A decline in mean sodium excretion was larger in ages 40-49 than in other age groups, and for ages 40-69 combined, the decline was 0.9-1.1 g per day for men and women. Mean sodium excretion declined to 10 g or less per day for men and women aged 60-69. Mean potassium excretion did not change except for men aged 60-69 with an increase in potassium. Sodium/potassium ratio tended to decline for women aged 40-49, and declined significantly for other sex-age groups. A larger reduction in sodium excretion was seen among persons with a history of hypertension compared to those without it. CONCLUSIONS: A significant reduction in urinary excretion of sodium and sodium/potassium ratio was observed in a community-based health education program. Men and women aged 60-69 reached a recommended level of 10 g or less in sodium intake.

Adult↗
PubMed1998

Response to head-up tilt testing in patients with situational syncope.

The results of head-up tilt testing were compared between 24 patients with situational syncope and 44 age-matched patients with typical vasovagal syncope. Patients with situational syncope showed poor positive responses, especially in the passive tilt results (8.3% vs. 39%, p = 0.0078).

Adult↗
PubMed1998

Analysis of human herpesvirus 6 U3 gene, which is a positional homolog of human cytomegalovirus UL 24 gene.

The US22 gene family was first discovered in human cytomegalovirus (HCMV) and contains several conserved amino acid motifs. Human herpesvirus 6 (HHV-6) also encodes several genes belonging to the US22 family, including the U3 gene (a positional homolog of HCMV UL24). Because the gene products of the US22 gene family function as gene regulators in general, we analyzed the HHV-6A U3 gene. Six transcripts with different molecular weights of 7.5-1.8 kb were detected by Northern blot analysis using a U3-specific probe. Sequence analyses of the respective cDNA clones and primer extension experiments revealed that the U3 gene encoded the 2.0- and 3.5-kb transcripts and had no splicing within the U3 gene region. By immunofluorescence testing using antibodies raised to a fusion protein of MBP (maltose-binding protein) and U3, the U3 viral antigen was detected as early as 24 h p.i. in HHV-6A-infected U373 cells. The antigens were found in cytoplasmic granules, preferentially in the endoplasmic reticulum. Moreover, cotransfection assay using a luciferase gene expression system revealed that the U3 gene product was capable of activating the human immunodeficiency virus long terminal repeat promoter in CV1 cells.

Cytomegalovirus↗
PubMed1998

Conversion of temperature-sensitive to -resistant gene expression due to mutations in the promoter region of the melibiose operon in Escherichia coli.

The melibiose utilization system of Escherichia coli W3133, a derivative of K12, is nonfunctional between 37 and 42 degreesC. The reason for this temperature sensitivity was thought to be that the melibiose transporter (MelB) of W3133 cells was temperature-sensitive. A mutant W3133-2 has been isolated as a temperature-resistant strain that can utilize melibiose between 37 and 42 degreesC. However, we found that the melibiose transporter of the W3133-2 was still temperature-sensitive. Half-life activities of the melibiose transporter at 37 degreesC (or 40 degreesC) in both E. coli W3133 and W3133-2 were exactly the same. Furthermore, we found that the nucleotide sequence of coding region of the melB structural gene (the second gene of the melibiose operon) of W3133-2 was exactly the same as that of W3133. Activity of alpha-galactosidase (product of the first gene, melA, of the melibiose operon) of W3133 cells grown at 40 degreesC was very low, although that of W3133-2 cells grown at 40 degreesC was high. These observations suggested that expression of the melibiose operon in W3133 is also temperature-sensitive. In fact, we found that the expression in W3133 cells was temperature-sensitive, while that in W3133-2 cells was temperature-resistant, by analyzing mRNA levels using the Northern blot method. Furthermore, we identified mutations in the promoter region of the melibiose operon of W3133-2 that resulted in the elongation of an 18 nucleotide inverted repeat sequence to a 28-nucleotide repeat sequence present immediately upstream of the -35 region. This may stabilize a possible stem structure due to the inverted repeat at 37-42 degreesC.

Base Sequence↗
PubMed1998

Alcohol intake and premature coronary heart disease in urban Japanese men.

To examine the relation between alcohol intake and the incidence of coronary heart disease among Japanese, the authors analyzed data from a prospective study of 8,476 Japanese male employees, who were 40-59 years old at baseline (between 1975 and 1984) and worked for 13 urban companies in Osaka, Japan. These men were followed until the end of 1993, on average, an 8.8-year follow-up. Eighty-three coronary heart disease events (54 myocardial infarction, 32 angina pectoris) occurred during the employment period under study. Compared with the risk of coronary heart disease for never drinkers, the age-adjusted relative risk for those with an increased ethanol intake was lower, but the risk did not appear to be reduced further with the intake of > or = 69 g of ethanol per day. The multivariate relative risk adjusted for age, serum total cholesterol, cigarette smoking, body mass index, left ventricular hypertrophy, and a history of diabetes mellitus was 0.83 (95% confidence interval (CI) 0.24-2.86) in exdrinkers, 0.69 (95% CI 0.37-1.29) in drinkers of 1-22 g/day of ethanol, 0.55 (95% CI 0.29-1.05) in drinkers of 23-45 g/day, 0.41 (95% CI 0.19-0.88) in drinkers of 46-68 g/day, and 0.59 (95% CI 0.23-1.51) in drinkers of > or = 69 g/day. The inverse association with alcohol intake was similar between myocardial infarction and angina pectoris. Alcohol intake seemed to prevent the premature incidence of coronary heart disease among urban Japanese middle-aged men.

Adult↗
PubMed1998

Clinical effect of immunochemotherapy for a patient with advanced gallbladder cancer: report of a case.

A 56-year-old woman was admitted presenting with a sensation of abdominal fullness. She was diagnosed to have advanced gallbladder cancer with carcinomatous peritonitis, as well as lymph node and liver metastases. We obtained highly purified tumor cells and tumor-infiltrating lymphocytes (TIL) from extirpated cervical lymph nodes and peritoneal effusion, and the chemosensitivity of these cells was tested with an MTT assay. Intensive chemotherapy with cisplatin (CDDP) and 5-fluorouracil (5-FU) was then performed according to the results of the MTT assay. Thereafter, cytotoxic T-lymphocytes (CTL) were induced in mixed cultures of autologous tumor cells and peripheral blood lymphocytes, and adoptive immunotherapy was performed with TIL and CTL. The malignant ascites and metastatic lesions disappeared after the intraperitoneal administration of CDDP and the transfer of TIL and CTL, and subsequently the patient's quality of life improved. This patient could return to work; however, liver metastasis was later observed, and she died 14 months after the initial diagnosis. Combination therapy with anticancer drugs and activated killer cells was thus found to be effective in a patient with advanced gallbladder cancer.

Adenocarcinoma↗
PubMed1998

Homeobox genes in hematopoiesis and leukemogenesis.

Homeobox genes have a strikingly conserved 61-amino acid sequence, encoding DNA-binding domain. Some homeobox genes, located in four clusters are designated HOX A through D, while others are known as divergent homeobox genes. Many researchers have demonstrated that hematopoietic cells express many homeobox genes. Induced over- and under-expression of these genes has been used to demonstrate their affect on some aspects of hematopoiesis and leukemogenesis. Recently, knock-out mice of homeobox genes by targeted disruption have also been used to examine their hematological effect. There are examples of the aberrant expression of a homeobox gene causing leukemias in humans. In pre-B acute lymphoblastic leukemia (ALL) with t(1;19) translocation, a fusion protein is created between E2A and a homeobox gene PBX. In T-cell ALL with t(10;14) translocation, the HOX 11 gene is deregulated. In acute myeloid leukemia (AML) with t(7;11) translocation, the HOX A9 gene is rearranged. In this review article, many functions of homeobox genes both at the early stem cell level as well as at the later stages of hematopoietic differentiation, and the leukemogenic effect of altered homeobox genes are discussed.

3T3 Cells↗
PubMed1998

In vitro synthesis of multicopy single-stranded DNA, using separate primer and template RNAs, by Escherichia coli reverse transcriptase.

A minor population of wild strains of Escherichia coli contains a retron, a retroelement responsible for the synthesis of multicopy single-stranded DNA (msDNA). The retron is a genetic element consisting of the gene for reverse transcriptase (RT) and the msr-msd region under a single promoter. A single RNA transcript from the msr-msd region serves not only as a template but also as a primer for msDNA synthesis. Here, using a cell-free system with purified RT from retron Ec73, we examined whether the reaction can occur in a bimolecular reaction with use of separately expressed msr and msd transcripts. DNA sequencing of the cell-free product revealed that the sequence of the 5'-end region was identical to that of msDNA-Ec73, indicating that the cDNA synthesis was primed from the 2'-OH group of the specific internal G residue of the primer RNA, identical to the branching G residue in the RNA molecule of msDNA-Ec73. The present results raise an intriguing possibility for a role of bacterial retrons in vivo, the possibility that cellular mRNAs can be converted into cDNAs in retron-harboring cells if the mRNAs contain a sequence complementary to the sequence directly upstream of the branching G residue of the msr RNA transcript.

DNA, Bacterial↗
PubMed1998

Mutants of Citrobacter freundii that transport and utilize melibiose.

We have isolated mutants of Citrobacter freundii that can grow on melibiose. Inducible alpha-galactosidase activity and melibiose transport activity were detected in the mutant cells but not in the wild-type cells. We detected a DNA region which hybridized with melB (the gene for the melibiose transporter) DNA of Escherichia coli in the chromosomal DNA of wild-type C. freundii. Protons, but not sodium ions, were found to be the coupling cations for melibiose (and methyl-beta-D-thiogalactoside) transport in the mutant cells.

Biological Transport↗