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H Tsuda

Publications and source records attributed to H Tsuda.

At least 73 records · Page 4Linked to original sources
PubMed2001

[Hemophagocytic syndrome with hemophagocytes in the peripheral blood].

A 79-year-old man developed a high fever, facial erythema, anemia and thrombocytopenia during conservative therapy for ischemic colitis. Peripheral hemophagocytes (PHP) were identified in smear specimens of peripheral blood, and hemophagocytes also showed proliferation in the bone marrow. After treatment with steroid and antibiotics under a diagnosis of bacteria-associated hemophagocytic syndrome, the patient recovered rapidly. Although the prognosis of hemophagocytic syndrome (HPS) depends on the underlying disease, any delay in diagnosis can sometimes result in a poor outcome in cases of infection-associated hemophagocytic syndrome. In the present case, early diagnosis of bacteria-associated hemophagocytic syndrome was made by detection of PHP. The appearance of PHP in virus-associated hemophagocytic syndrome (VAHS) and after administration of macrophage colony stimulating factor has been described. However, the significance and cytological characteristics of PHP have been unknown. In this report, we propose that PHP can be a useful indicator for early diagnosis of HPS, and we report 7 additional cases in which the PHP was detected retrospectively. The cytological characteristics and biological significance of PHP are discussed.

Aged↗
PubMed2001

[Therapeutic plasmapheresis for the prevention of congenital complete heart block associated with anti-SS-A/Ro antibody and anti-SS-B/La antibody].

OBJECTIVES: Neonatal lupus erythematosus is characterized by transient lupus abnormalities, various systemic and hematological abnormalities, and congenital complete heart block (CCHB). It is well known that anti-SS-A/Ro antibody (52 kD/60 kD) and anti-SS-B/La antibody are associated with CCHB. This study was conducted to evaluate the effects of the removal of anti-SS-A/Ro antibody (52 kD/60 kD) and anti-SS-B/La antibody from plasma in pregnant women whose fetuses are at a high risk of developing CCHB. MATERIALS & METHODS: Fifteen pregnant patients positive for anti-SS-A/Ro antibody and anti-SS-B/Laantibody were subjected weekly to double filtration plasmapheresis to remove both antibodies. Antibody titers were measured by double immunodiffusion (DID) and ELISA. RESULTS: As a result, all women gave birth to live babies, but CCHB was recognized in one baby. No transient lupus abnormalities were recognized in any of the babies. Fourteen patients showed decreased antibody titers by ELISA during plasmapheresis. However, the patient who was delivered of a baby with CCHB showed an increase of antibody titers by ELISA while the DID method showed a decrease of antibody titers. CONCLUSION: Our study suggested that plasmapheresis prevents CCHB associated with anti-SS-A/Ro and anti-SS-B/La antibody. Also, it is important to monitor the antibody titer regularly during the course of pregnancy, because it may increase due to worsening of the mother's primary disease.

Adult↗
PubMed2000

Connexin43 suppresses MFG-E8 while inducing contact growth inhibition of glioma cells.

Gap junction expression has been reported to control the growth of a variety of transformed cells. We undertook parallel analysis of connexins Cx32 and Cx43 in glioma cells, which revealed potential mechanisms underlying this phenomenon and led to several novel findings. Cx43, but not Cx32, suppressed C6 glioma cell growth. Paradoxically, Cx32 transfection resulted in severalfold more dye transfer than Cx43. However, Cx43 transfectants shared endogenous metabolites more efficiently than Cx32 transfectants. Interestingly, a significant portion of Cx43 permeants were incorporated into macromolecules more readily than those that transferred via Cx32. Cx43 induced contact inhibition of cell growth but in contrast to other reports, did not affect log phase growth rates. Cell death, senescence, or suppression of growth factor signaling was not involved because no significant alterations were seen in cell viability, telomerase, or mitogen-activated protein kinase activity. However, suppression of cell growth by Cx43 entailed the secretion of growth-regulatory factors. Most notably, a major component of conditioned medium that was affected by Cx43 was found to be MFG-E8 (milk fat globule epidermal growth factor 8), which is involved in cell anchorage and integrin signaling. These results indicate that Cx43 regulates cell growth by the modulation of extracellular growth factors including MFG-E8. Furthermore, the ability of a Cx to regulate cell growth may rely on its ability to mediate the intercellular transfer of endogenous metabolites but not artificial dyes.

Amino Acid Sequence↗
PubMed2000

Combined measurement of the c-erbB-2 protein in breast carcinoma tissues and sera is useful as a sensitive tumor marker for monitoring tumor relapse.

c-erbB-2 protein levels in tissue extracts and sera were determined in a retrospective analysis of 158 patients who underwent surgical resection of breast carcinoma by means of a sandwich enzyme immunometric assay (EIA) using monoclonal antibodies (MAbs) directed to the extracellular domain of the c-erbB-2 oncogene protein (ErbB-2). In the analysis of tissue extracts, 48 samples (30.3%) showed ErbB-2 levels exceeding 18.0 ng/mg protein (group A), while in 110 samples these levels were below 18.0 ng/mg protein (group B). Immunohistochemical examination of resected tissues using anti-c-erbB-2 antibody revealed positive staining in 93.8% (45/48) in group A and 13.6% (15/110) in group B (p < 0.00001). The proportion of patients who preoperatively showed a serum ErbB-2 value above 5.4 ng/ml was 52.1% (25/48) in group A and 10.0% (11/110) in group B (p < 0.00001). Thus, the level of ErbB-2 in tissue extracts was significantly associated with immunohistochemistry and ErbB-2 levels in preoperative sera. During follow-up, 48 patients (30.3%) developed recurrent disease: 17 in group A (35.4%) and 31 in group B (28.2%). From an ROC analysis based on the postoperative serum ErbB-2 levels in patients either with or without relapse, the cutoff value of serum ErbB-2 for tumor relapse was determined to be 6.5 ng/ml. The sensitivity of serum ErbB-2 in patients with relapsed breast cancer was 58.3% (21/36) overall, 84.6% (11/13) in group A and 43.5% (10/23) in group B. In the analysis of serum samples taken before relapse, 90.9% (10/11) of the subjects in group A and 26.7% (4/15) of those in group B were shown to be positive for serum ErbB-2. Serum ErbB-2 in group A was a more sensitive marker than other tumor markers such as CEA, CA15-3, and NCC-ST-439. Thus, the determination of ErbB-2 in tissue extracts of breast carcinoma may be useful for assessing c-erbB-2 protein expression in the primary tissue and indicates that serum ErbB-2 may be a sensitive marker for monitoring tumor relapse.

Antigens, Tumor-Associated, Carbohydrate↗
PubMed2000

Xenopus Xenf: an early endodermal nuclear factor that is regulated in a pathway distinct from Sox17 and Mix-related gene pathways.

We report a novel zygotic gene encoding a Xenopus endodermal nuclear factor, Xenf. Expression of Xenf starts at the late blastula stages and is decreased after gastrulation. Xenf shows no structural homology to any known proteins. When GFP-tagged Xenf is overexpressed in Xenopus cells, Xenf protein is localized to the nucleus, associating closely with the chromosomes. In animal cap assays, Xenf expression is strongly activated by mRNA injection of Vg1 and VegT, maternal vegetal genes that can induce endodermal differentiation. In contrast, Xenf is not induced by endoderm-inducing zygotic transcription factors such as Sox17 and Mix-related genes. In turn, Xenf does not activate expression of Sox17, Mixer or Milk. Thus, Xenf is regulated by maternal vegetal positional information in a parallel manner to Sox17 and Mix-related gene pathways.

Amino Acid Sequence↗
PubMed2000

Differential effect of subcellular localization of communication impairing gap junction protein connexin43 on tumor cell growth in vivo.

There is a large body of evidence suggesting the connexin gap junction proteins appear to act as tumor suppressors, and their tumor inhibitory effect is usually attributed to their main function of cell coupling through gap junctions. However, some cancer cells (e.g. the rat bladder carcinoma BC31 cell line) are cell-cell communication proficient. Using specific site-directed mutagenesis in the third membrane-spanning (3M) domain of connexin43 (Cx43), we abolished the intrinsic gap junction intercellular communication (GJIC) in BC31 cells either by closing the gap junctional channels or by disruption of the transport of connexin complexes to the lateral membrane. Clones of BC31 cells transfected with a dominant negative Cx43 mutant giving rise to gap junctional channels, permeable only for a small tracer (neurobiotin), displayed accelerated growth rate in vivo, showing the critical role of selective gap junctional permeability in the regulation of cell growth in vivo. The use of other dominant-negative mutants of Cx43 also suggested that the effect of impaired communication on the tumorigenicity of cancer cells depends on the subcellular location of connexin. Inhibition of intrinsic GJIC in BC31 cells by sequestering of Cx protein inside the cytoplasm, due to expression of dominant-negative transport-deficient Cx43 mutants, did not significantly enhance the growth of transfectants in nude mice, but occasionally slightly retarded it. In contrast, augmentation of GJIC in BC31 cells by forced expression of wild-type Cx43, or a communication-silent mutant, fully suppressed tumorigenicity of these cells. Overall, these results show that cell coupling is a strong, but not the sole, mechanism by which Cx suppresses growth of tumorigenic cells in vivo; a GJIC-independent activity of Cx proteins should be considered as another strong tumor-suppressive factor.

Animals↗
PubMed2000

Aberrant DNA methylation precedes loss of heterozygosity on chromosome 16 in chronic hepatitis and liver cirrhosis.

The aim of this study was to examine the significance of aberrant DNA methylation, the participation of which in genetic instability is controversial, in hepatocarcinogenesis. The DNA methylation status of the region around the promoter of the E-cadherin tumor suppressor gene, which is located on 16q22.1, and the allelic status at the D16S421 locus, which is adjacent to the E-cadherin locus, were examined using microdissected liver specimens from 38 hepatocellular carcinoma (HCC) patients. Almost all of the non-cancerous liver tissues showed histological findings compatible with chronic hepatitis and cirrhosis, which are considered to be precancerous conditions. DNA hypermethylation was detected in 61% of the non-cancerous liver tissues. The incidence of DNA hypermethylation in the non-cancerous liver tissues of patients with HCCs also showing DNA hypermethylation (72%) was significantly higher than that of patients without DNA hypermethylation in their HCCs (53%, P<0.05). Loss of heterozygosity (LOH) at the D16S421 locus was detected in 35% of the non-cancerous liver tissues. The incidence of LOH in the non-cancerous liver tissues of patients with HCCs also showing LOH was 78%, whereas LOH was not detected in non-cancerous liver tissues of patients without LOH in their HCCs. Fifty-two percent of the non-cancerous liver tissues showed both or neither of DNA hypermethylation and LOH; the incidence of DNA hypermethylation alone in noncancerous liver tissue was 41%. The incidence of LOH alone in non-cancerous liver tissue (7%) was significantly lower compared to those of the former two cases (P<0.0001). These data suggest that aberrant DNA methylation participates in the precancerous stage of hepatocarcinogenesis by preceding, or causing, LOH.

Adult↗
PubMed2000

c-erbB-2 protein overexpression and p53 immunoreaction in primary and recurrent breast cancer tissues.

BACKGROUND AND OBJECTIVES: We investigated whether expression levels of c-erbB-2 and p53 proteins in breast cancer tissues differ in primary and metastatic lesions. METHODS: Immunohistochemical staining or sandwich enzyme immunoassay was used to determine expression levels of c-erbB-2 and p53 proteins in 42 breast cancer samples from 21 patients. Estrogen (ER) and progesterone receptors (PgR) were also measured by enzyme immunoassay in each case. All patients had undergone radical surgery for primary tumors and surgical resection of asynchronous metastatic lesions. Thirteen patients (62%) were premenopausal and 14 (67%) received postoperative adjuvant therapies. Median disease-free survival time was 26 months (range, 5-104). The resected metastatic lesions included 1 in the liver, 3 in the lung, and 3 in the supraclavicular lymph nodes. The remaining 14 were local skin lesions. RESULTS: There was no difference in the positivity rate of c-erbB-2 (38%: 8/21) and p53 (39%: 7/18) expression between the primary tumors and the recurrent lesions. In addition, no discordant c-erbB-2 or p53 expression was observed between the primary tumors and their respective metastatic lesions. Positivity rates for ER and PgR were 50% (10/20) and 60% (12/20) for the primary tumors, but only 25% (5/20) and 30% (6/20) for the recurrent lesions, respectively (P = 0. 19 for ER and P = 0.11 for PgR). CONCLUSIONS: c-erbB-2 and p53 expression levels in breast cancer cells were almost unchanged as the disease progressed and/or in response to adjuvant therapies, regardless of the hormone receptor status.

Adult↗
PubMed2000

Type I and type II T-cell profiles in aplastic anemia and refractory anemia.

Immune-mediated suppression of hematopoiesis has been considered the most important mechanism in the development of idiopathic aplastic anemia (AA) and some types of myelodysplastic syndrome (MDS). Using flow cytometric analysis of intracellular cytokine expression at the single-cell level, we analyzed helper-T (Th) and cytotoxic-T (Tc) subsets in patients with AA and MDS of refractory anemia (RA) subtype. The results showed marked increases in the Th1/Th2 ratio and Tc1/Tc2 ratio in both AA and MDS/RA. Overproduction of cytokines inhibitory to hematopoiesis reported so far might be a reflection of imbalanced development of Th and Tc. Determination of the factors that affect Th and Tc profiles may lead to further understanding of immunological states and the development of effective immunotherapy in AA as well as some types of MDS.

Anemia, Aplastic↗
PubMed2000

Prevention of colon carcinogenesis and carcinoma metastasis by orally administered bovine lactoferrin in animals.

Bovine lactoferrin (bLF), a milk protein known to have bacteriostatic properties was examined for its preventive effects on colon and other organ carcinogenesis and experimental metastasis. (Experiment 1) The influence on colon carcinogenesis was investigated in male rats treated with azoxymethane (AOM), then received 2 or 0.2% bLF for 36 weeks. Significant reduction in the incidence (27% and 46% of the control, respectively) and number of adenocarcinomas of the large intestine was observed. (Experiment 2) In BALB/c mice bearing subcutaneous (s.c.) implants of colon carcinoma 26 (Co 26Lu). bLF demonstrated significant inhibition of spontaneous lung metastasis (approximately 43% of the control). Number of cytotoxic asialoGM1+ and CD8+ cells in white blood cells increased (171% and 122% of control, respectively) after treatment. Results of those experiments indicate that bLF remarkably prevents colon carcinogenesis and lung metastasis of colon carcinoma cells, possibly due to increasing cytotoxic cells in the peripheral blood.

Animals↗
PubMed2000

Chemoprevention of lung cancer by lycopene.

An investigation was conducted to assess the chemopreventive potential of lycopene (LP), a naturally occurring hydrocarbon carotenoid found in tomatoes and their products, administered during the post-initiation stage in a multiorgan carcinogenesis model. One hundred eighteen B6C3F1 mice of both sexes were subjected to combined treatment with diethylnitrosamine (DEN), N-methyl-N-nitrosourea (MNU) and 1,2-dimethylhydrazine (DMH) from day 11 after birth to week 9 (DMD treatment) (groups 1 and 2) or given their vehicles (group 3). Then group 1 received LP (25 or 50 ppm in drinking water) for 21 weeks from weeks 11 to 32. Group 2 served as a carcinogen alone control and group 3 was given only LP (25 or 50 ppm). The incidences and multiplicities of lung adenomas plus carcinomas combined in male mice in group 1 receiving LP 50 ppm were significantly decreased as compared to the DMD alone or DMD and LP 25 ppm group values (75.0 vs 18.8%, P < 0.02; 0.94+/-0.17 v.s 0.25+/-0.14, P < 0.001). While hepatocellular carcinomas were lacking in the DMD and LP groups, two cases were found in the DMD alone group (not statistically significant). The values for aberrant crypt foci (ACF) and tumors in the colon and kidney did not show any significant variation among the carcinogen-treated subgroups. The results of this study provide evidence that the tomato carotenoid, lycopene, may have potential as a chemopreventive agent against carcinogenesis in the male lung.

1,2-Dimethylhydrazine↗
PubMed2000

A proposal for the histopathological diagnosis of ductal carcinoma in situ of the breast.

BACKGROUND: As the incidence of ductal carcinoma in situ (DCIS) is increasing, it is necessary to make a guideline for the pathological examination and diagnosis of DCIS, by creating criteria based on clinical and biological aspects of the disease. METHOD: We collected biopsy specimens originally diagnosed as benign lesions, from patients who subsequently developed invasive carcinoma in the ipsilateral breast. The histology of the biopsy specimens was re-evaluated principally according to the 1995 Philadelphia Consensus on DCIS. Histopathological agreement on each biopsy specimen was made by the JBCS Study Group members under a multiviewer microscope. In the course of making conclusive agreements among the pathologists, we developed a consensus for the histopathological diagnosis of DCIS, especially non-comedo types. RESULTS: DCIS is defined as a carcinoma of ductal epithelial origin, without any evidence of stromal invasion. It is necessary to note the methods of pathologic examination required to diagnose DCIS. Stromal invasion is an important prognostic factor, and should be diagnosed with caution. Classification of proliferative ductal lesions as benign or malignant (DCIS), the subtype of DCIS (nuclear grade, architecture, and necrosis), and the histological grading of DCIS are proposed and recommended. CONCLUSION: Although we have made a new proposal according to current concepts, there are still several unresolved problems. Thus further examination and modification will be necessary in the future.

Breast Neoplasms↗
PubMed2000

Treatment of noninvasive carcinoma: fifteen-year results at the National Cancer Center Hospital in Tokyo.

The introduction of screening mammography (MMG) will lead to increased detection of preclinical early breast cancer in Japan. It has become more important to understand the nature of these lesions. We tried to elucidate the long term prognosis and clinical and pathological characteristics of noninvasive cancers. A total of 336 (5.4%) ductal carcinoma in situ (DCIS) and 32 (0.5%) lobular carcinoma in situ (LCIS) were diagnosed in 6 277 breast carcinomas at the National Cancer Center Hospital from 1962 to 1995. Most (80%) LCIS occurred in premenopausal women. LCIS has significantly higher bilaterality than that of DCIS. Local recurrence occurred in approximately 10% of patients after breast conserving surgery for DCIS and LCIS. Four patients died of breast carcinoma, which were initially diagnosed as noninfiltrating carcinoma. The 15-year cause specific survival rates of patients with DCIS and LCIS were 98.5 % and 100 %, respectively.

Breast Neoplasms↗
PubMed2000

Evaluation of histopathological criteria for identifying node-negative breast cancer with high risk of early recurrence in the NSAS-BC protocol study.

BACKGROUND: The histopathological criteria for high-risk node-negative primary breast cancer stated in the National Surgical Adjuvant Study of Breast Cancer (NSAS-BC) protocol were used to grade a consecutive series of 488 cases at our hospital. METHODS: To validate the criteria retrospectively, we examined the histological features of node-negative primary breast cancers which showed early relapse within 2 years after surgical therapy. RESULTS: Early relapse occurred in 12 patients, distant metastases in 11, and local recurrence in one. Among 278 cases followed for up to 1.5 years or longer, early systemic relapse was detected in 10 (5.8%) of 172 higher-grade tumors (9 invasive ductal carcinomas of nuclear grade 3 and one invasive ductal carcinoma of nuclear grade 2) and one stromal cell sarcoma. Among the 115 low-risk tumors, only one case (0.9%) of invasive ductal carcinomas with nuclear grade 1 showed early local recurrence. Early relapse occurred in only one (1.5%) of 67 tumors with an invasive component of 1.0 cm but in 11 (5.2%) of 211 tumors with an invasive component of 1.1 cm. The recurrence rate increased to 9.3% (8/86) when tumor invasion was 2.1 cm. In 12 cancers showing recurrence, strand structure, large central acellular zones, and squamoid features were histologically observed in four, two, and three cases, respectively. The present results confirmed the reported tendency of correlation between strand pattern and bone metastasis, large central acellular zones and lung and brain metastasis, and squamoid features and lung metastasis. Synchronous bilateral and unilateral multiple cancers were characterized by lower nuclear grades. CONCLUSIONS: At our hospital, the criteria used in the NSAS-BC protocol were demonstrated to identify node-negative cancers with high risk of early recurrence at a hospital level. To further identify groups prone to recurrence, longer follow-up would be necessary. In addition, the histological criteria could be improved to correlate with patient outcome more accurately.

Adult↗
PubMed2000

Good or evil: CD26 and HIV infection.

Acquired immune deficiency syndrome (AIDS) is an incurable disease at present and so many efforts to conquer this disease are being made around the world. In studies of human immunodeficiency virus (HIV) infection and the disease progression, it has been reported that T cells expressing CD26 are preferentially infected and depleted in HIV-infected individuals. CD26 is a widely distributed 110 kDa cell-surface glycoprotein with known dipeptidyl peptidase IV (DPPIV) activity in its extracellular domain. This ectoenzyme is capable of cleaving N-terminal dipeptides from polypeptides with either proline or alanine residues in the penultimate position. On human T cells, CD26 exhibits the co-stimulatory function and plays an important role in immune response via its ability to bind adenosine deaminase (ADA) and association with CD45. Recent studies have been stripping the veil from over the relationship between CD26 and HIV infection. Susceptibility of cells to HIV infection is correlated with CD26 expression, and HIV transactivator Tat and envelope protein gp120 are reported to interact with CD26. These observations indicate that CD26 is closely involved in HIV cell entry and that CD26-mediated T cell immune response is suppressed. In addition, it has been demonstrated that the anti-HIV and chemotactic activities of RANTES (regulated on activation, normal T cell expressed and secreted) and stromal cell-derived factor-1 (SDF-1) are controlled with the DPPIV activity of CD26. Thus, the regulation of the function of chemokines by CD26/DPPIV appears to be essential for lymphocyte trafficking and infectivity of HIV strains.

Amino Acid Sequence↗
PubMed2000

Milk and dairy products in cancer prevention: focus on bovine lactoferrin.

Milk and dairy products constitute an important part of the western style diet. A large number of epidemiological studies have been conducted to determine effects of consumption on cancer development but the data are largely equivocal, presumably reflecting the different included components. It has been proposed that whereas fats in general could promote tumor development, individual milk fats like conjugated linoleic acid could exert inhibitory effects. There is also considerable evidence that calcium in milk products protects against colon cancer, while promoting in the prostate through suppression of circulating levels of 1,25-dihydroxyvitamin D3. Whey protein may also be beneficial, as shown by both animal and human studies, and experimental data have demonstrated that the major component bovine lactoferrin (bLF), inhibits colon carcinogenesis in the post-initiation stage in male F344 rats treated with azoxymethane (AOM) without any overt toxicity. The incidence of adenocarcinomas in the groups receiving 2% and 0.2% bLF were thus 15% and 25%, respectively, in contrast to the 57.5% control value (P<0.01 and P<0.05, respectively). Results in other animal models have provided further indications that bLF might find application as a natural ingredient of milk with potential for chemoprevention of colon and other cancers.

Adenocarcinoma↗
PubMed2000

Obsession of hearing music: from the viewpoint of Morita theory.

We present two typical cases among five Japanese students who have complained of hearing music. They were found among 638 student case reports during 4 years at the mental health service center of a preparatory school. We diagnosed the complaint of hearing music as a symptom of obsession. Morita therapy was an effective treatment for this symptom. We discuss the characteristics of the symptom as an obsession and the therapy in the light of Morita theory.

Adolescent↗