Search PubMed⌕ Search

Biomedical subjects

M Hagiwara

Publications and source records attributed to M Hagiwara.

At least 73 records · Page 4Linked to original sources
PubMed1998

[Current trends and problems in disclosure to lung cancer patients].

To assess current trends in the disclosure of cancer, we studied patients with primary lung cancer. Ninety-nine of 101 surgical patients (98.0%) and 96 of 128 non-surgical patients (75.0%) had been informed of their illness. Family members of 2 surgical patients refused to allow disclosure due to concerns about mental intolerance. Reasons for non-disclosure to non-surgical patients ranged from rejection by family members (29 patients) to a lack of ability to understand (3 patients). No mental problems were observed after disclosure. All but 11 patients were informed of their cancers by their physicians. Decisions regarding disclosure were not related to the pathological type or clinical stage of the cancer. For example, small cell carcinoma did not influence methods of or decisions concerning disclosure. Among non-surgical patients, the frequency of disclosure decreased with aging. However, no clear-cut factor appeared to influence the disclosure of metastatic sites. Views about informed consent are still at a transitional stage in Japan. The doctrine that patients have the right to be informed of their cancers and to choose their treatment has not always been the best policy in practice. Nevertheless, it seems desirable that approaches to disclosure adequately reflect the special needs of each patient and provide as much information as possible to allow each patient to make an accurately informed decision about treatment options. Such approaches would foster better relationships between physicians and their patients and relieve physicians from pressure to tell a medical lie.

Adult↗
PubMed1997

Identification of a novel nuclear speckle-type protein, SPOP.

A novel antigen recognized by serum from a scleroderma patient was identified by expression cloning from the HeLa cell cDNA library. The cloned cDNA encoded a 374-amino acid protein with a relative molecular mass of 47,000 and a predicted amino acid sequence 62.7% identical to the hypothetical protein of Caenorhabditis elegans, T16H12.5. The deduced amino acid sequence had a typical POZ domain and an unidentified region conserved during evolution. No zinc finger or RNA recognition motifs were found in this clone. The 2 kbp mRNA encoding the novel clone SPOP (speckle-type POZ protein) was found to be expressed in all human tissues examined. HA-tagged SPOP, transfected and overexpressed in COS7 cells, exhibited a discrete speckled pattern in the nuclei and was co-localized with the splicing factor, snRNP B'/B. Deletion analysis revealed that both the POZ domain and the evolutionarily conserved region at the amino-terminus are required for the nuclear speckled accumulation of SPOP.

Amino Acid Sequence↗
PubMed1997

Controlled gene expression with a reverse tetracycline-regulated retroviral vector (RTRV) system.

A retroviral vector was constructed with an autoregulatory cassette to allow expression of the gene of interest in response to oral administration of doxycycline (Dox) in vivo. The cassette contains all the components of the reverse tetracycline-regulated (rtTA) system, a drug selectable marker with the internal ribosome entry site and the gene of interest (GFP). FACS analyses showed an induction of GFP-fluorescence of two orders of magnitude in retrovirus-infected 208F cells dependent on the amount of Dox in the medium. Furthermore, oral administration of Dox resulted in GFP expression in transplanted 208F cells in the peritoneal cavity of nude mice. Thus this reverse tetracycline-regulated retroviral vector (RTRV) system simplifies the delivery of controllable genes to cultured and implanted cells. It is hoped that this approach may pave the way to controlled gene expression during a particular window of time in gene therapy applications.

Animals↗
PubMed1997

Expression cloning and intracellular localization of a human ZF5 homologue.

We isolated a cDNA encoding a human homologue of ZF5 (hZF5), which has five Kruppel-like C2H2 type zinc fingers at carboxyl terminus and the BTB/POZ (poxvirus and zinc finger) at the amino terminus, using autoimmune sera from a patient with overlap syndrome (dermatomyositis and scleroderma). Sequencing of the entire cDNA revealed an open reading frame (ORF) of 1349 bp with a deduced protein sequence of 449 amino acid residues and a calculated molecular weight of 51.3 kDa. The deduced amino acid sequence of hZF5 is highly homologous to mouse ZF5 (99.3% identity). Immunofluorescence studies revealed that HA-tagged hZF5 transiently expressed in COS-7 cells showed the nuclear dot pattern in the BTB/POZ domain-dependent manner.

Adult↗
PubMed1997

Phosphorylation of ATF-1 enhances its DNA binding and transcription of the Na,K-ATPase alpha 1 subunit gene promoter.

Transcriptional activity of both ATF-1 and CREB is enhanced by protein phosphorylation. While enhancement has been attributed to an increase in binding affinity for a co-activator (CBP), induction of the DNA binding activity by phosphorylation is an open question. Using the Na,K-ATPase alpha1 subunit gene promoter, which has an asymmetrical ATF/CRE site, we analyzed the effect of phosphorylation on DNA binding activity of the ATF-1-CREB heterodimer. Dephosphorylation of the heterodimer in nuclear extracts reduced binding to the ATF/CRE site. Phosphorylation of ATF-1 at Ser63 enhanced its binding to the ATF/CRE site in both the homodimeric and heterodimeric forms. Transcription of the Na,K-ATPase alpha 1 subunit gene promoter was also stimulated by phosphorylated ATF-1 in vitro.

Activating Transcription Factor 1↗
PubMed1997

Low frequency of autoantibodies against Ki-67 antigen in Japanese patients with systemic autoimmune diseases.

The Ki-67 antigen, which is recognized by the monoclonal antibody Ki-67, is a marker of cell proliferation. During cDNA cloning using sera from a patient with systemic lupus erythematosus, we obtained a positive clone encoding part of Ki-67. We determined the frequency of autoantibodies against Ki-67 in patients with systemic autoimmune diseases. Serum samples from 252 patients with rheumatic diseases were examined by immunoblotting with HeLa nuclear extract and the recombinant N-terminus of the Ki-67 antigen. Autoantibodies against Ki-67 antigen were detected in two out of 76 patients with systemic lupus erythematosus and one out of 90 patients with scleroderma. While, in a previous report, anti-Ki-67 antibodies were frequently targeted by a certain strain of autoimmune mice, our results indicated that Ki-67 was a minor target of autoantibodies among Japanese patients with systemic autoimmune diseases.

Autoantigens↗
PubMed1997

Alteration of platelet aggregation in patients with thyroid disorders.

To determine whether Graves' disease or primary hypothyroidism influence platelet function, we evaluated platelet aggregation in the platelet-rich plasma (PRP) from such patients. Platelet aggregation induced by adenosine diphosphate (ADP) in blood obtained from patients with untreated Graves' disease was significantly lower than normal, whereas that in patients with untreated primary hypothyroidism was relatively increased. The magnitude of platelet aggregation induced by collagen in both groups of patients resembled that induced by ADP. However, significant differences were evident between the two diseases (P < .05). In addition, we observed a significant inverse correlation between the extent of platelet aggregation and plasma levels of thyroid hormones (triiodothyronine [T3], thyroxine [T4], and free T3). Platelet aggregation returned to normal when the euthyroid condition was obtained in the patients following administration of antithyroid drugs or thyroid hormone. The findings are consistent with the possibility that thyroid hormones influence platelet aggregation partly via inhibition of myosin light-chain kinase (MLCK).

Adenosine Diphosphate↗
PubMed1997

Anti-mitosin antibodies in a patient with chronic graft-versus-host disease after allogeneic bone marrow transplantation.

In a patient undergoing allogeneic BMT for ALL, chronic GVHD (cGVHD) with skin changes developed within 110 days after transplantation. One year post-BMT, anti-nuclear antibodies were detected. The patient's serum was used for immunoscreening of a HeLa cDNA library. Ten different overlapping positive clones were found to be partial clones of mitosin, a 350-kDa nuclear phosphoprotein which shows a speckled nuclear distribution in S phase and which relocates to the centromere and mitotic apparatus in M phase. Although autoantibodies against centromere protein-F, which is very similar to mitosin, have been reported in patients with cancer, this is the first report of autoantibodies against mitosin in a patient with cGVHD.

Adult↗
PubMed1997

Functional analyses of mammalian protein kinase C isozymes in budding yeast and mammalian fibroblasts.

BACKGROUND: The PKC1 gene of Saccharomyces cerevisiae encodes a homologue of mammalian protein kinase C (PKC) that is required for yeast cell growth. Pkc1 has been proposed to regulate a protein kinase cascade which includes the Bck1, Mkk1/Mkk2 and Mpk1 kinases. The functional relationship between Pkc1 and mammalian PKCs is unknown. Another signal transduction in Saccharomyces cerevisiae, the mating pheromone signalling pathway, is mediated by a heterotrimeric G protein, and causes cell cycle arrest in the G1 interval. It is not clear whether PKC is involved in this pathway. The effects of overexpression of PKCs in mammalian cells have been widely studied to analyse the function of PKCs in vivo. RESULTS: We isolated a human cDNA which encodes a protein kinase C type eta (PKC-eta) by complementation of pkc1 mutations in Saccharomyces cerevisiae. The human PKC-eta was able to complement the growth defect caused by the deletion of PKC1, whereas PKC-eta was unable to suppress the defect caused by deletion of BCK1. We also isolated human cDNAs that can suppress the adaptation defect of sst2. One of them encodes a protein kinase C type delta (PKC-delta). Expression of this gene in yeast stimulated an adaptation to the pheromone response. Human PKC-delta suppressed the adaptation defect of a pheromone receptor mutation lacking its C-terminal domain, but not that of a G protein beta-subunit mutation eliminating signal-induced phosphorylation, and not the lethality of the gpa1 null mutation. Moreover, overexpression of PKC-eta in NIH3T3 cells induced anchorage-independent growth. CONCLUSIONS: PKC-eta has a biological activity which is closely related to Pkc1, and PKC-eta activates the Pkc1-mediated pathway through an activation of the Bck1 kinase that is a homologue of MAP kinase kinase kinase. PKC-eta appears to play a critical role in growth control of yeast and mammalian cells. Suppression experiments with PKC-delta suggest that PKC-delta desensitizes the pathway by regulating an aspect of G protein function.

Adaptation, Biological↗
PubMed1997

Echographia as a symptom of interictal state in an epileptic patient: a case report.

Echographia is a phenomenon in which a patient continuously translates verbal stimuli into writing. We encountered a patient with epilepsy who developed visual echographia during interictal periods. In this case, echographia was observed during two different periods, namely the period of disturbed consciousness after the epileptic seizure and the period of clear consciousness after suppression of the seizures. Disinhibition due to disturbance of the consciousness is considered to have been the cause of echographia in the former period. In the latter period, it is considered that echographia was caused by the release of lower function from suppression of upper function by brain dysfunction, as the after effect of status epilepticus. As echographia can be observed in epileptic patients, attention and careful observation by epileptologists is needed.

Adolescent↗
PubMed1997

Characterization of a serum response factor-like protein in Saccharomyces cerevisiae, Rlm1, which has transcriptional activity regulated by the Mpk1 (Slt2) mitogen-activated protein kinase pathway.

The Mpk1 (Slt2) mitogen-activated protein (MAP) kinase has been implicated in several biological processes in Saccharomyces cerevisiae. The Rlm1 protein, a member of the MADS box family of transcription factors, functions downstream of Mpk1 in the pathway. To characterize the role of Rlm1 in mediating the transcriptional activation by the Mpk1 pathway, we constructed a LexA-Rlm1 deltaN chimera in which sequences, including the MADS box domain of the Rlm1 protein, were replaced by the LexA DNA binding domain and tested the ability of this chimera to activate a LexA operator-controlled reporter gene. In this assay, the Rlm1 protein was found to activate transcription in a manner regulated by the Mpk1 pathway. The Mpk1 protein kinase phosphorylated Rlm1 deltaN in vitro and the LexA-Rlm1 deltaN chimera protein was phosphorylated in vivo in a Mpk1-dependent manner. These results suggest that Mpk1 regulates the transcriptional activity of Rlm1 by directly phosphorylating it. We identified a Mpk1-like protein kinase, Mlp1, as an Rlm1-associated protein by using the yeast two-hybrid system. Overexpression of MLP1 suppresses the caffeine-sensitive phenotype of the bck1 delta mutation. The additivity of the mlp1 delta defect with the Mpk1 delta defect with regard to the caffeine sensitivity, combined with the results of genetic epistasis experiments, suggested that the activity of Rlm1 is regulated independently by Mpk1 MAP kinase and the Mlp1 MAP kinase-like kinase.

Amino Acid Sequence↗
PubMed1997

Antithrombotic effects of the novel inhibitor of thrombin-induced offtelet aggregation and thrombus formation, 3-[2-[1,1':2',1"]-terphenyl-4'-yl)ethyl]phenoxyacetic acid.

The new compound 3-[2-([1,1':2,1"]-terphenyl-4'yl)ethyl]phenoxyacetic acid (F1070) was synthesized and its effects on platelet aggregation induced by thrombin, thrombin receptor agonist peptide (TRAP), ADP and collagen were evaluated in humans, guinea pigs and rats, and were compared with the effects of he thrombin antagonists argipidine and (D)Phe-Pro-Arg-CH2Cl (FPR). F1070 inhibited the platelet aggregation induced by these agonists and was highly selective in its inhibition of thrombin. F1070 inhibited fibrin formation induced by thrombin, but far less effectively than argipidine. In a guinea pig model of extracorporeal circulation thrombosis, F1070 (10 mg/kg p.o.) significantly inhibited the development of a thrombus. F1070 is thus a key compound that should facilitate the development of new orally active antithrombotic drugs that are specific for thrombin.

Animals↗
PubMed1997

High-affinity binding of DTZ323, a novel derivative of diltiazem, to rabbit skeletal muscle L-type Ca++ channels.

A novel derivative of diltiazem (1,5-benzothiazepine Ca++ antagonist), DTZ323, 3-(acetyloxy)-5-[2-[[2-(3,4-dimethoxyphenyl)ethyl]-methylamino]eth yl]-2,3-dihydro-2-(4-methoxyphenyl)-1,5-benzothiazepine-4(5H)-one, was characterized by radioligand binding experiments with rabbit skeletal T-tubule membranes in terms of the affinity and the selectivity to the binding sites for the three classical calcium antagonists, such as dihydropyridines, phenylalkylamines and benzothiazepines. DTZ323, like diltiazem and clentiazem, exhibited complete and concentration-dependent inhibition of d-cis-[3H]diltiazem binding to the membrane with a slope factor close to unity. Ki values indicated that DTZ323 (Ki = 6.6 +/- 0.6 nM, mean +/- S.E., n = 4) was 48 times and 9 times more potent than diltiazem and clentiazem, respectively. DTZ323 partially inhibited the specific binding of a dihydropyridine ligand, (+)-[3H]PN200-110, at 37 degrees C. The equilibrium saturation study showed that DTZ323 reduces the affinity for the (+)-[3H]PN200-110 binding in a concentration-dependent manner with a slight decrease in the density of the binding sites. DTZ323 also inhibited the specific binding of a phenylalkylamine ligand, (-)-[3H]D888, completely as did diltiazem. DTZ323 (1 microM) had no effect on the dissociation rate of d-cis-[3H]diltiazem at 2 degrees C, whereas 30 microM verapamil increased the dissociation rate, which suggested that DTZ323 inhibits the specific binding of d-cis-[3H]diltiazem in a manner similar to other competitive ligands for the benzothiazepine binding site. These results indicate that DTZ323 is a selective ligand for the 1,5-benzothiazepine binding site with the highest affinity among the diltiazem derivatives.

Animals↗
PubMed1997

Anticoagulant activity of the novel thrombin inhibitor 1-butyl-3-(6,7-dimethoxy-2-naphthylsulfonyl) amino-3-(3-guanidinopropyl)-2-pyrrolidinone hydrochloride.

1-Butyl-3-(6,7-dimethoxy-2-naphthylsulfonyl)amino-3-(3-guanidin opropyl)-2-pyrrolidinone hydrochloride (CAS 173440-64-7, SPI-501), which has highly selective thrombin-inhibitory activity, caused a concentration-dependent increase in the time taken for coagulation induced by thrombin in rabbit plasma. The IC50 of SPI-501 was 1.7 mumol/l. Argipidine also prolonged coagulation time and its activity was one order of magnitude greater than that of SPI-501. SPI-501 and argipidine caused dose-dependent increases in the activated partial prothrombin time (APTT) and prothrombin time (PT) of rat plasma. When APTT and PT were measured, IC50 values of SPI-501 were 38.0 and 18.5 mumol/l and those of argipidine, 1.4 and 1.9 mumol/l, respectively. Intravenous administration of SPI-501 (10 and 30 mumol/kg) and argipidine (1 and 3 mumol/kg) prolonged both APTT and PT in rats. While SPI-501 was less potent than argipidine, the durations of the effects of both were the same.

Animals↗
PubMed1997

Antithrombotic effects of 3-([1:1',2':1"]-3'-terphenyl)propanol in animals.

3-([1:1',2':1"]-3'-Terphenyl)propanol (CAS 186835-06-3, F050) and acetylsalicylic acid (ASA) inhibited platelet aggregation induced by CaCl2, arachidonic acid, collagen, adenosine diphosphate (ADP) and thrombin in guinea pigs, rabbits and rats in vitro. However, F050 had a wider spectrum of actions than ASA. Orally administered F050 inhibited platelet aggregation ex vivo. F050 significantly reduced the thrombus formation in the extracorporeal circulation thrombosis model in guinea pigs. It inhibited erythrocyte hemolysis induced by hypotonic NaCl, while ASA did not. F050, but not ASA, inhibited increases in platelet [CA2+]i caused by thrombin in guinea pigs. F050 is a parent compound that will facilitate the development of an orally active drug for the treatment of thrombotic diseases.

Animals↗
PubMed1996

Purification and identification of a major activator for p38 from osmotically shocked cells. Activation of mitogen-activated protein kinase kinase 6 by osmotic shock, tumor necrosis factor-alpha, and H2O2.

A stress-activated, serine/threonine kinase, p38 (also known as HOG1 or MPK2) belongs to a subgroup of mitogen-activated protein kinase (MAPK) superfamily molecules. An activity to activate p38 (p38 activator activity) as well as p38 activity itself were greatly stimulated by hyperosmolar media in mouse lymphoma L5178Y cells. The activator activity has been purified by sequential chromatography. A 36-kDa polypeptide that was coeluted with the activity in the final chromatography step was identified as MAPK kinase 6 (MAPKK6) by protein microsequencing analysis. Monoclonal and polyclonal antibodies raised against recombinant MAPKK6 recognized specifically the 36-kDa MAPKK6 protein but did not cross-react with MKK3 proteins. The use of these anti-MAPKK6 antibodies revealed that two major peaks of the p38 activator activity in the first chromatography step reside in the activated MAPKK6. Using a genetic screen in yeast, we isolated MKK3b, an alternatively spliced form of MKK3. Like MKK3 and MAPKK6, MKK3b was shown to be a specific activator for p38 and was activated by osmotic shock when expressed in COS7 cells. Immunoblotting analysis revealed that MAPKK6 is expressed highly in HeLa and KB cells and scarcely in PC12 cells, whereas MKK3 and MKK3b are expressed in all cells examined. Immunodepletion of MAPKK6 from the extracts obtained from L5178Y cells and KB cells exposed to hyperosmolar media depleted them of almost all of the p38 activator activity, indicating that MAPKK6 is a major activator for p38 in an osmosensing pathway in these cells. In addition, MAPKK6 was activated strongly by tumor necrosis factor-alpha, H2O2, and okadaic acid and moderately by cycloheximide in KB cells. Thus, there are at least three members of p38 activator, MKK3, MKK3b, and MAPKK6, and MAPKK6 may function as a major activator for p38 when expressed.

Amino Acid Sequence↗
PubMed1996

Calmodulin-dependent protein kinase II potentiates transcriptional activation through activating transcription factor 1 but not cAMP response element-binding protein.

Activating transcription factor 1 (ATF1) and the cAMP response element-binding protein (CREB) are members of the CREB/ATF family implicated in cAMP- and calcium-induced transcriptional activation. Although ATF1 and CREB share extensive homology, the function of ATF1 is poorly understood. Its phosphorylation state and activation by Ca2+- and calmodulin-dependent protein kinase (CaMK) II were therefore examined. Phosphopeptide mapping analysis and Western blotting studies demonstrated that in vitro, CaMK II phosphorylates only Ser63 (corresponding to Ser133 of CREB), which is essential for the activation, and not Ser72 (corresponding to Ser142 of CREB), which is a negative regulation site. Both ATF1 and CREB bound CBP in a phosphorylation-dependent manner. As expected from these in vitro studies, transient transfection studies revealed that ATF1 is activated by CaMK II. Our findings suggest that CaMK II mediates transactivation of cAMP responsive genes via ATF1.

Activating Transcription Factor 1↗