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T Hachiya

Publications and source records attributed to T Hachiya.

At least 109 records · Page 6Linked to original sources
PubMed1997

[Tumor lysis syndrome after treatment for mediastinal non-Hodgkin's lymphoma].

An 18-year man was admitted to the hospital because of acute dyspnea. Roentgenological examination revealed a large anterior mediastinal tumor. Histologic examination of a specimen from a cervical lymph node yielded a diagnosis of non-Hodgkin's lymphoma of, diffuse, large, T-cell type. Acute respiratory failure and a massive pleural effusion developed, and mechanical ventilation was begun. Chemotherapy with adriamycin, vincristine, cyclophosphamide, and prednisolone resulted in rapid shrinking of the mass. Acute renal failure developed because of hypoperfusion of the kidney caused by acute circulatory failure and the tumor lysis syndrome, and rapid increases in the concentrations of lactate dehydrogenase, creatine phosphokinase, and uric acid in serum after the tumor collapsed. Mediastinal malignant lymphoma often forms a bulky mass, and effective chemotherapy, while it can prolong survival, may also cause the tumor lysis syndrome.

Acute Disease↗
PubMed1996

The effect of a 5HT2 receptor antagonist sarpogrelate (MCI-9042) treatment on platelet function in Buerger's disease.

The effect of a new, specific 5-HT2 receptor antagonist sarpogrelate (MCI-9042) treatment on platelet function and serotonin levels in both plasma and whole blood in Buerger's disease, was assessed in a pilot study. We investigated 10 patients suffering from Buerger's disease. Sarpogrelate in a dose of 3 x 100 mg a day was given p.o. for a period of 8 weeks. It was well tolerated and no major side effects were noted. It was judged to be effective in some patients as assessed by its effect on both subjective complaints and objective evaluation of ankle pressure index (API). Sarpogrelate induced a significant decrease in plasma serotonin (5-HT) concentration starting after the 4th week which lasted through to the 8th week of the study, whereas plasma tryptophan concentration increased significantly after 2 and 4 weeks. There were no changes in plasma 5-HIAA concentration. On the other hand whole blood 5-HT concentration increased significantly after 2 weeks, and there was also a tendency to increase in whole blood tryptophan concentration (p = 0.052). Platelet aggregation induced by ADP and collagen did not show any statistically significant changes. Surprisingly, platelet aggregation induced by serotonin increased significantly after 2 weeks and even more so after 4 weeks of treatment, and then it returned to baseline values after 8 weeks. There was no effect on platelet count, APTT, TT and fibrinogen concentration.

Administration, Oral↗
PubMed1996

Accelerated degradation of PML-retinoic acid receptor alpha (PML-RARA) oncoprotein by all-trans-retinoic acid in acute promyelocytic leukemia: possible role of the proteasome pathway.

Acute promyelocytic leukemia (APL) is associated with a chromosomal translocation t(15;17) and successfully differentiated by all-trans-retinoic acid (ATRA) in vivo as well as in vitro. The PML-retinoic acid receptor alpha (RARA) oncoprotein, which is generated by the translocation, blocks the differentiation, and ATRA is thought to modulate the dominant negative function of PML-RARA. However, the molecular effect of ATRA on PML-RARA is unknown. In this study, we showed by means of immunoblotting that the expression of PML-RARA decreased within 12 h in APL cells treated with ATRA at concentrations greater than 0.1 microM. The decrease of PML-RARA was associated with restoration of the normal subcellular PML localization. PML-RARA transcripts were not down-regulated by ATRA. However, lactacystin, a specific inhibitor of the proteasome, almost completely inhibited the decrease of PML-RARA. These data indicate that the PML-RARA degradation is accelerated by pharmacological concentrations of ATRA, suggesting that ATRA allows APL cells to differentiate by relieving the differentiation block.

Acetylcysteine↗
PubMed1996

Isolation and characterization of cDNA for DREF, a promoter-activating factor for Drosophila DNA replication-related genes.

DREF, a transcription regulatory factor which specifically binds to the promoter-activating element DRE (DNA replication-related element) of DNA replication-related genes, was purified to homogeneity from nuclear extracts of Drosophila Kc cells. cDNA for DREF was isolated with the reverse-transcriptase polymerase chain reaction method using primers synthesized on the basis of partial amino acid sequences and following screening of cDNA libraries. Deduced from the nucleotide sequences of cDNA, DREF is a polypeptide of 701 amino acid residues with a molecular weight of 80,096, which contains three characteristic regions, rich in basic amino acids, proline, and acidic amino acids, respectively. Deletion analysis of bacterially expressed DREF fused with glutathione S-transferase (GST-DREF) indicated that a part of the N-terminal basic amino acid region (16-115 amino acids) is responsible for the specific binding to DRE. A polyclonal and four monoclonal antibodies were raised against the GST-DREF fusion protein. The antibodies inhibited specifically the transcription of DNA polymerase alpha promoter in vitro. Cotransfection experiments using Kc cells demonstrated that overproduction of DREF protein overcomes the repression of the proliferating cell nuclear antigen gene promoter by the zerknüllt gene product. These results confirmed that DREF is a trans-activating factor for DNA replication-related genes. Immunocytochemical analysis demonstrated the presence of DREF polypeptide in nuclei after the eighth nuclear division cycle, suggesting that nuclear accumulation of DREF is important for the coordinate zygotic expression of DNA replication-related genes carrying DRE sequences.

Amino Acid Sequence↗
PubMed1996

Anti-Ro/SSA associated recurrent annular erythema: autoimmune response to recombinant 60- and 52-kDa Ro/SSA proteins.

Recurrent annular erythema associated with anti-Ro/SSA antibody response has recently been recognized as a distinct clinical entity. Serum samples from 15 anti-Ro/SSA positive patients with recurrent annular erythema were tested by enzyme-linked immunosorbent assay (ELISA) for reactivity with full-length recombinant human 60-kDa and 52-kDa Ro/SSA proteins. All the 15 sera were positive for anti-60-kDa Ro/SSA, and 11 sera (73.3%) contained anti-52-kDa Ro/SSA. These results suggest the importance of 60-kDa polypeptide component of the Ro/SSA particle as a potential target in anti-Ro/SSA associated annular erythema.

Adolescent↗
PubMed1996

Precise determination of TSH receptor antibody activity in serum containing bovine TSH (bTSH) binding antibody by absorption using denatured bTSH or sheep FSH.

A previous report demonstrated that sera with bovine TSH (bTSH) binding antibody showed abnormally negative TSH receptor antibody (TRAb) activity in the standard TRAb assay method. The corrected TRAb activity calculated by the determination of the nonspecific binding of the labeled bTSH for each test serum [NSB(T)] resulted in positive TRAb activity. However, the precise calculation was difficult because NSB(T) level was significantly higher than the nonspecific binding in normal pool serum [NSB(N)] level. In the present experiment the determination of the TRAb activity was performed after absorption of bTSH binding antibodies by the heat-denatured bTSH to obtain more precise TRAb activity. In addition, absorption by sheep FSH (sFSH) was performed because almost all bTSH binding antibodies showed specific binding to the alpha-subunit of mammalian pituitary glycoprotein hormones in our previous study. Three days absorption of test serum using 1 mU of the heat-denatured bTSH (100 degrees C for 1 h) or 5 mU of sFSH was chosen as optimal because NSB(T) decreased remarkably to NSB(N) levels. The corrected TRAb determined after these absorptions decreased significantly compared to the corrected TRAb activity without the absorption. When the complete absorption of bTSH binding antibody was performed by the decrease of the NSB(T) level to the NSB(N) level, the TRAb activity determined by these two different absorptions was almost similar (difference was less than 10%). However, it was difficult to obtain the precise TRAb activity in the cases with extremely high bTSH binding antibody, because the NSB(T) level was higher than the NSB(N) level by the incomplete absorption of bTSH binding antibody.

Absorption↗
PubMed1996

Identification of the nuclear localization signal of mouse DNA primase: nuclear transport of p46 subunit is facilitated by interaction with p54 subunit.

DNA polymerase alpha-primase is a replication enzyme necessary for DNA replication in all eukaryotes. Mouse DNA primase is composed of two subunits: a 46 kDa protein (p46), which is the catalytic subunit capable of RNA primer synthesis, and a 54 kDa protein (p54), whose physiological role is not clear. To understand the structure-function relationship of DNA primase, we set out to characterize these two subunits individually or in combination using a cDNA expression system in mammalian cultured cells, and determined the subcellular distribution of ectopically expressed DNA primase. The p54 expressed in COS-1 cells after transfection was predominantly localized in the nucleus, whereas p46 was retained in the cytoplasm as shown by indirect immunofluorescence analysis. Using several mutant proteins with deletions or substitutions as well as chimeric constructs, we identified the nuclear localization signal of p54 as RIRKKLR, encoded near the amino terminus (residues 6-12). Furthermore, co-expression of both p46 and p54 subunits markedly altered the subcellular distribution of p46; co-expressed p46 was transported into the nucleus as efficiently as p54. These results demonstrate that p54 has a nuclear localization signal and is able to be translocated into the nucleus independently of DNA polymerase alpha subunits. In contrast, p46 lacks a nuclear localization signal, and its nuclear translocation is facilitated by interaction with p54. We present here first evidence for a novel role of p54 in the nuclear translocation process, and a piggy-back binding transport mechanism of mouse DNA primase.

3T3 Cells↗
PubMed1996

Two cases of severe bronchiectasis successfully treated with a prolonged course of trimethoprim/sulfamethoxazole.

Two patients with severe bronchiectasis, one patient without other disease and the other with hyper IgE syndrome, were successfully treated with long-term therapy with low doses of trimethoprim and sulfamethoxazole (TMP-SMZ). Recurrent respiratory infections with productive cough and high fever were resistant to various antibiotics and often disturbed the patients' activities in daily life. However, they showed marked improvement following TMP-SMZ therapy, which was started for methicillin-resistant Staphylococcus aureus (MRSA) infection. MRSA disappeared some months later, but Pseudomonas aeruginosa appeared again in the sputum. Both patients, however, have remained free from symptoms for over one year.

Adult↗
PubMed1996

[Two cases of primary Sjögren's syndrome with pulmonary involvement histopathological study of open-lung biopsy specimens].

We report two cases of primary Sjögren's syndrome with pulmonary involvement, in which open lung biopsies were done. The patient in the first case was a 58-year-old woman and the patient in the second case was a 54-year-old woman. Both patients were admitted to our hospital because of dry coughing and exertional dyspnea. Chest X-ray films and CT scans showed interstitial shadows in both cases and multiple bullae in the first case. Pulmonary-function tests showed decreased diffusing capacity, and examination of bronchoalveolar lavage fluid revealed increased percentages of lymphocytes. Open-lung biopsy specimens showed thickening of the alveolar septa and interstitial mononuclear cell infiltration, composed predominantly of lymphocytes, with lymphoid follicles in both cases, and peribronchiolar mononuclear cell infiltration in the first case. Therefore, the histopathological diagnosis was cellular interstitial pneumonia with lymphoid follicles. Both patients were treated with oral corticosteroids. Symptoms were relieved and laboratory findings improved.

Biopsy↗
PubMed1996

[Effects of compton scatter in quantitative brain SPECT].

Effects of Compton scatter has been investigated for quantitative single-photon emission computed tomography. Using a technique proposed by Ichihara and Ogawa (triple-energy window method) as a gold standard, effects of correcting the scatter has been evaluated for 5 different phantom configurations, as well as a clinical cerebral blood flow study with use of 123I-IMP. Without the scatter correction but with a correction for attenuation, a conventional reconstruction provided a non-uniform distribution for uniform phantom configurations, and the quantitative pixel counts being highly dependent on size and shape of the objects. On the other hand, a uniform distribution and quantitative pixel counts that were independent of size or shape of the object were obtained by applying the scatter correction using a conventional attenuation correction technique with use of a theoretical mu value of 0.146 cm-1, thus suggesting importance of the scatter correction. Similar results were observed without the scatter correction, if an empirical value of mu of 0.07 cm-1 was used in the attenuation correction. However, this procedure was found to decrease the image contrast between the high count and low count regions. Significant underestimation of 20-30% was caused in cortical gray matter regions, and overestimation of 20% in the white matter regions. In practical clinical studies, magnitude of the error is still unknown, and is probably dependent on shape, size and radioactivity distribution of the object. A further systematic study is required in order to investigate significance of the scatter correction in real clinical studies.

Adult↗
PubMed1996

[Pulmonary malignant fibrous histiocytoma presenting as hemothorax].

A 39-year-old woman, who suffered from a sudden episode of severe left-sided back pain, was admitted to our hospital because of hemothorax. Chest CT scans revealed a mass extending from the left hilum to the posterior thoracic wall. The mass occluded the left pulmonary artery at the left main bronchus. Examination of a frozen section of a specimen obtained during a thoracotomy showed a sarcomatous tumor. A left pneumonectomy was then performed. Microscopic examination of a specimen revealed that the tumor was composed of spindle cells with cellular atypia and mitosis forming fascicles and storiform arrays. Malignant fibrous histiocytoma (storiform-pleomorphic pattern) was diagnosed. Chemotherapy was carried out six times during the year after surgery. No recurrence of the tumor has been seen during 20 months of follow-up.

Adult↗
PubMed1996

[A case report of Takayasu's arteritis with aortic pseudoaneurysm caused by aortic perforation].

A 47-year-old man presented with hemoptysis. From around June 20, 1995, he had symptoms of a common cold, but hemoptysis suddenly occurred on July 1 and he was brought to hospital. The chest X-ray film showed pleural effusion and enlargement of the mediastinum. CT scans showed calcification of the aorta, with a pseudoaneurysm 8 cm in diameter anterior to the descending aorta. When thoracotomy was performed under partial extracorporeal circulation, the thoracic cavity was found to be filled with bloody hydrothorax and hematoma, and the lower lobe of the left lung was adherent to the descending aorta. After a longitudinal incision was made in the aorta, a perforation 7 mm in diameter was identified in the posterior wall, and this was assumed to be the cause of the pseudoaneurysm. This part of the aorta was replaced with a Woven Dacron graft. Takayasu's arteritis was diagnosed by histological examination of the resected specimen, and the changes in the aortic wall at the site of perforation were considered to be chronic. About 30% of patients with this disease have aortic ectasia, but only a few pseudoaneurysms have been reported. Since the pseudoaneurysm occurred in our patient after reduction in the dose of medication, the development of perforation was suggested to be related to this change. In the future, this patient will require careful follow up for anastomotic aneurysm.

Aneurysm, False↗
PubMed1996

Highly sensitive ELISA for soluble Fas in serum: increased soluble Fas in the elderly.

We have developed and characterized a highly sensitive ELISA for soluble Fas (sFas) in the serum. The linearity of calibrator range was 0.06-2.00 micrograms/L and the detection limit was 0.01 microgram/L. The average within- and between-run CVs were 3.9% and 3.8%, respectively. The recovery of added sFas to serum was 93-118%. The effects of possible interferences (tryglyceride, hemoglobin, bilirubin) were negligible. We determined serum sFas in 155 healthy subjects, ages 20-69. The mean value of sFas in men (2.50 +/- 0.63 micrograms/L, n = 78) was significantly higher than that in women (2.01 +/- 0.53 micrograms/L, n = 77) (P < 0.001). Furthermore, there was a significant correlation between serum sFas concentration and age (men, r = 0.397, P < 0.001; women, r = 0.569, P < 0.001). Although the concentrations of sFas tended to increase with aging, it remains to be clarified how Fas-mediated apoptosis relates to aging.

Adult↗
PubMed1995

The rck/p54 candidate proto-oncogene product is a 54-kilodalton D-E-A-D box protein differentially expressed in human and mouse tissues.

Expression of the RCK gene, which is a target gene on 11q23 of the t(11;14) (q23;q32) translocation in the B-cell lymphoma cell line RC-K8, was studied by Northern and Western blot analyses. The RCK gene product is a member of the D-E-A-D box protein/RNA helicase family. With the use of Northern blot analysis, a 7.5-kb transcript of the RCK gene was shown to be expressed ubiquitously in human and mouse tissues. Polyclonal antibodies against the RCK gene product were raised, and the RCK gene expression pattern was examined in human and mouse tissues. Two different polyclonal anti-rck antibodies detected a specific 54-kilodalton product named rck/p54 in the majority of human and mouse tissues tested by Western blot analysis. However, rck/p54 was shown to be very low in the human brain and was not detectable in lumbar muscle and lung tissues, although RCK mRNA is abundantly present in these tissues. It is of interest that malignant transformed human cells arising from tissues with low or no expression of rck/p54, such as neuroblastoma, glioblastoma, rhabdomyosarcoma, and lung cancer cell lines, produced a moderate amount of rck/p54 protein, suggesting that rck/p54 plays a role in tumorigenesis. In addition, the rck/p54 protein was localized to cytoplasm by immunostaining with the use of laser microscopy and by subcellular fractionation.

Amino Acid Sequence↗
PubMed1995

Endogenous cleavage of phospholipase C-beta 3 by agonist-induced activation of calpain in human platelets.

Two membrane-associated phosphoinositide-specific phospholipase Cs (mPI-PLC-1 and mPI-PLC-2) and a cytosolic enzyme (cPI-PLC) that were activated by brain G-protein beta gamma subunits have been isolated from human platelets. The truncation of mPI-PLC-1 that was mediated by mu-calpain induced much higher activation by beta gamma subunits (Banno, Y., Asano, T., and Nozawa, Y. (1994) FEBS Lett. 340, 185-188). On the basis of size and immunological cross-reactivity, mPI-PLC-1 (155 kDa) was PLC-beta 3, and mPI-PLC-2 (100 kDa) was its truncated form. The cPI-PLC (140 kDa) was recognized by the antibody selective for internal sequences of PLC-beta 3 but not by the antibody raised against its carboxyl terminus, indicating that it may be related to PLC-beta 3. Treatment of human platelets with A23187 and dibucaine, activators of calpain, caused cleavage of actin-binding protein and talin in a time-dependent manner. At the same time, decrease of PLC-beta 3 (155 and 140 kDa) and concomitant increase of the 100-kDa product of cleavage were observed on immunoblots with the antibody to internal sequences of PLC-beta 3. Furthermore, stimulation of platelets by natural agonists, thrombin and collagen, caused the cleavage of PLC-beta 3 (155 and 140 kDa) and an increase of 100 kDa PLC-beta 3 in a time- and dose-dependent manner. The cleavage of these PLC-beta 3 enzymes was completely blocked by calpain inhibitor, calpeptin, indicating that the PLC-beta 3 modification may be a consequence of platelet activation leading to activation of calpain. This is the first demonstration that PLC-beta 3 is indeed cleaved by calpain upon platelet activation by physiological agonists. The cleavage of PLC-beta 3 evoked by thrombin and collagen but not ADP was correlated with irreversible aggregation, suggesting that the PLC-beta 3 modification may play a role in secondary irreversible aggregation in agonist-stimulated human platelets.

Amino Acid Sequence↗
PubMed1995

Expression patterns of DNA replication enzymes and the regulatory factor DREF during Drosophila development analyzed with specific antibodies.

Specific antibodies were prepared against Drosophila DNA polymerase epsilon and DREF, a regulatory factor for DNA replication-related genes. Using these antibodies together with those for DNA polymerase alpha and proliferating cell nuclear antigen (PCNA), we examined expression patterns and sub-cellular distributions of these proteins during Drosophila development. DNA polymerase alpha, epsilon and PCNA proteins were maternally stored in unfertilized eggs and maintained at high levels during embryogenesis. With distinct nuclear localization, proteins were observed in embryos at interphase stages throughout the 13 nuclear division cycles, suggesting that they all participate in rapid nuclear DNA replication during these cycles. In contrast, maternal storage of a DREF protein was relatively low and its level increased throughout embryogenesis. Strong nuclear staining with the anti-DREF antibody was not observed until the nuclear division cycle 8. Immunostaining of various larval tissues from transgenic flies carrying the PCNA gene promoter-lacZ fusion gene revealed co-expression of DREF, PCNA and lacZ, suggesting that DREF regulates the expression of PCNA gene in these tissues. In addition, we detected a relatively high level of DREF in adult males as well as females. Since DNA polymerase alpha, epsilon and PCNA are hardly detectable in adult males, DREF very likely regulates genes other than those closely linked to DNA replication in adult males.

Animals↗
PubMed1995

Demonstration of thyroactive smaller components released from TSAb-IgG by protease digestion.

Thyroid stimulating (TS) activity (cAMP production in thyroid cells) and TSH binding inhibition (TBI) activity (determined by TSH receptor assay) in fragments released from TSAb-IgG by protease digestion were examined. The unbound fraction (UF) and the bound fraction (BF) were separated using a protein A-Sepharose column after papain hydrolysis (more hydrolysis at pH 5.0 than pH 7.5) of TSAb-IgG. When both fractions were gel filtrated on a Sephadex G-100 column, the TS and TBI activity were found in both Fab fraction (Mr 50 kDa) and the retarded fraction (between Mr 50 and 20 kDa) in the UF, and also in the first fraction (undigested IgG, Mr 160 kDa), the second fraction (Fc with tracer amounts of Fab, Mr 50 kDa), and the retarded fraction (between Mr 50 and 20 kDa) of the BF. The biological activity in the second fraction was suggested as being derived from Fab, because the activity bound to the anti-F(ab')2 column but did not bind to the anti-Fc column. Anti-Tg and anti-TPO activities were found in Fab, but were not found in the retarded fraction that consisted of Mr 20-30 kDa. In pepsin hydrolysis the UF from the protein A column consisted of both F(ab')2 (Mr 100 kDa) and pF'c (CH3) (Mr 25 kDa), and the BF consisted of only the undigested IgG. The biological activities were found in both the F(ab')2 fraction and the retarded fraction (between Mr 100 and 25 kDa). Anti-Tg and anti-TPO activities were found in F(ab')2, but no activity was observed in the Mr 25-kDa fraction. The present study showed that the biological activity of TSAb is distributed in not only the Fab or F(ab')2 fragment, but also in thyroactive smaller components (TSC) (Mr 20-30 kDa) without antigen-binding activity such as anti-Tg and anti-TPO. We suggest that TSC may be released from the Fab fragment region of TSAb-IgG by protease hydrolysis.

Animals↗