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H Handa

Publications and source records attributed to H Handa.

At least 163 records · Page 9Linked to original sources
PubMed1994

Transcriptional activation through the tetrameric complex formation of E4TF1 subunits.

Transcription factor E4TF1 is composed of two types of subunit, an ets-related DNA binding protein, E4TF1-60, and its associated proteins with four tandemly repeated Notch-ankyrin motifs, E4TF1-53 and E4TF1-47. To determine the functional domains, we constructed various mutants of the subunits. E4TF1-60 bound to DNA as a monomer. The ets domain and its N-terminal flanking region were necessary to recognize the specific DNA sequence. The 48 amino acids at the E4TF1-60 C-terminus were required for interaction with the other type of subunit. E4TF1-53 and E4TF1-47 share the N-terminal 332 amino acids but differ at the C-termini. They interacted with E4TF1-60 through the N-terminal flanking region to form a heterodimer. E4TF1-53 dimerized with itself, whereas E4TF1-47 did not. The C-terminal region specific for E4TF1-53 was required for the dimerization. Therefore, heterodimers composed of E4TF1-53 and E4TF1-60 were further dimerized, resulting in the formation of a tetrameric complex, which stimulated transcription in vitro. Heterodimers of E4TF1-47 and E4TF1-60 weakly stimulated transcription in vitro. The results indicated that the tetrameric complex formation of E4TF1 subunits was necessary to activate transcription efficiently in vitro.

Base Sequence↗
PubMed1994

An adult patient with cerebellar ganglioglioma.

We encountered a very rare patient with cerebellar ganglioglioma. To our knowledge, there are 17 reported patients with this disease, of whom ours (a 53-year-old male) was the oldest. The tumor was totally resected, but radiotherapy was also performed to prevent recurrence. He is completely symptom-free 9 months after operation.

Cerebellar Neoplasms↗
PubMed1994

Structure-activity relationships of HIV-1 PR inhibitors containing AHPBA.

A series of Human Immunodeficiency Virus type-1 protease (HIV-1 PR) inhibitors that contain 3-amino-2-hydroxy-4-phenylbutanoic acid (AHPBA) at the scission site of the substrate were prepared and evaluated for their inhibitory activity. Preliminary studies on the chain length of inhibitors and the hydroxyl configuration of AHPBA indicated that small (2S,3S)-derivatives, composed of the regions between the P3 and P2' sites, showed enough inhibitory activity toward HIV-1 PR to become prototypes for further structural modification. Systematic replacement at the sites from P3 to P2' revealed that some bicyclic heteroarylcarbonyl derivatives possessed strong potency and good enzyme selectivity.

Amino Acid Sequence↗
PubMed1994

Preparation of DNA-carrying affinity latex and purification of transcription factors with the latex.

We have developed DNA-carrying latex particles for the separation and purification of transcription factors. These particles consist of styrene (St), glycidyl methacrylate (GMA) and divinylbenzene (DVB). It was confirmed that the ethanolamine-treated surface of these particles suffered no nonspecific adsorption of proteins. To the latex particles sequence-specific DNA oligomers were immobilized via covalent coupling. A transcription factor, E4TF3, was efficiently purified to homogeneity using the latext particles. In contrast, the purification using DNA-carrying Sepharose gel yielded poor results. Compared to DNA-carrying Sepharose gel, the latex particles exhibited several times higher efficiency in the purification of E4TF3 from the crude nuclear extract.

Adsorption↗
PubMed1994

Brachial plexus injury with cough attack: case report.

Cough attacks elicited by movement of the neck and right arm are reported in a patient who had sustained several shoulder injuries and who had an anterior scalenectomy. The coughing was accompanied by weakness in the right upper limb. At exploration, the phrenic nerve was found adhered to the brachial plexus. The cough attacks disappeared, and the weakness of the right upper limb improved somewhat after lysis of the adhesions between the phrenic nerve and the plexus and after external neurolysis of the upper, middle, and lower trunks. Postoperatively, the patient could elevate his right arm without coughing.

Brachial Plexus↗
PubMed1994

Studies of human immunodeficiency virus type 1 (HIV-1) protease inhibitors. III. Structure-activity relationship of HIV-1 protease inhibitors containing cyclohexylalanylalanine hydroxyethylene dipeptide isostere.

Systematic replacement of the P4-P2 subsites of substrate-based human immunodeficiency virus type 1 protease (HIV-1 PR) inhibitors containing cyclohexylalanylalanine hydroxyethylene dipeptide isostere (Cha-psi [H.E.]-Ala) at positions corresponding to the scissile sites of substrates was carried out. The structure-activity relationship revealed that compounds with the combination of hydrophilic P3 and beta-branched hydrophobic P2 amino acids generally showed strong inhibitory activity against HIV-1 PR. In particular, compounds 4 (Boc-Orn-Val-Cha-psi [H.E.]-Ala-NHBun; Bu(n) = n-butyl, Ki = 11 nM) and 6 (Z-Orn-Val-Cha-psi [H.E.]-Ala-NHBun, Ki = 8 nM) exhibited good enzyme selectivity, possessing no significant inhibitory activities toward closely related aspartic proteases, pepsin, cathepsin D, and renin. As a possible model system for (anti-Mo-MSV/MLV complex (Mo-MSV = Moloney murine sarcoma virus; MLV = murine leukemia virus)) activity was investigated. Both compounds were found to inhibit moderately the focus formation of Mo-MSV/MLV complex in NIH3T3 cells (compound 4, IC50 = 1.8 microM; compound 6, IC50 = 1.0 microM).

Amino Acid Sequence↗
PubMed1994

[Immortalization of rat corneal epithelial cells by SV40-adenovirus recombinant vector].

Using a SV40-adenovirus recombinant vector, we have successfully established a rat corneal epithelial cell line (RatCE) and studied its biological characteristics. RatCE continued to grow for more than 400 generations. It proliferated centrifugally in the early phase of the culture (1-3 days in culture) and had a cobblestone-like appearance in confluency. Desmosomes and microvilli were clearly seen under a transmission electron microscope. RatCE could be stored in liquid nitrogen and its biological characteristics were: doubling time, 18.3 hrs, colony forming ability, 36%, and growth ability in soft agar, 2%. When the insoluble extract from RatCE was electrophoresed, insoluble proteins were seen at 36 kD, 40 kD, 44 kD, 48 kD, 56 kD, and 64 kD. Anti-64 kD cytokeratin antibody strongly reacted with numerous filaments in the cytoplasm of RatCE. Hence, RatCE possessed 64 kD corneal specific keratin. A large amount of fibronectin was also assessed at focal contact by immunohistochemistry. Thus, RatCE retains several kinds of epithelial characteristics, is derived from one clone, and is immortalized. RatCE will be a useful tool in studies of the corneal epithelium.

Animals↗
PubMed1994

Bradykinin and Met-T-kinin-Leu stimulated PGE2 production by rat macrophage and fibroblast.

T-kininogen degradation and kinin release were observed in rat macrophages cultured under acidic conditions. Bradykinin and Met-T-kinin-Leu (a kinin precursor) stimulated PGE2 production by macrophages and fibroblasts but had no effect on O2- production. PGE2 production by macrophages stimulated with 10 microM bradykinin increased by approximately 148% compared to non-stimulated macrophages (0.47 +/- 0.13 vs 0.31 +/- 0.16 ng 10(6) cells-1 30 min-1), and increased by 161% in stimulated as opposed to non-stimulated fibroblasts (0.50 +/- 0.07 vs 0.31 +/- 0.05 ng 10(5) cells-1 30 min-1). No O2- production was detectable in fibroblasts despite stimulation with PMA, A23187, bradykinin, and Met-T-kinin-Leu. O2- production by macrophages was 4.2 +/- 0.3 and 3.0 +/- 0.2 nmol 10(6) cells-1 min-1 after stimulation with PMA and A23187, respectively, but no O2- production was observed after stimulation with bradykinin or Met-T-kinin-Leu. These data suggest that bradykinin and the kinin precursor are implicated in granulomatous tissue formation and wound healing through arachidonic acid and its metabolites but not through O2-.

Animals↗
PubMed1994

[Outpatient chemotherapy with continuous infusion of 5-fluorouracil (CI 5-FU) and intravenous bolus leucovorin (IVB LV) in advanced gastrointestinal cancer].

This study was designed to evaluate the efficacy, toxicity, and quality of life (QOL) of outpatient chemotherapy with 5-FU and LV in advanced gastrointestinal cancer. Treatment consisted of CI 5-FU 450-500 mg/body/day, days 1-28, IVB LV 30 mg/body q wk. 5-FU was administered with the Baxter infusor (0.5 ml/hr). LV was not administered if Grade 2 mucositis occurred. Seven patients (pts) with advanced gastrointestinal cancer (esophageal -2, gastric -1, colorectal -4) have been treated to maintain the efficacy of prior inpatient chemotherapy, and two pts with colorectal cancer instead of oral UFT. And to evaluate toxicity and QOL, six pts (bile duct -1, gastric -2, colorectal -3) treated as adjuvant chemotherapy were added. The median duration of response of the nine pts was 3.03 months. Because of mucositis, the administration of LV was restricted. The mean administration of it was 2.1 times (62 mg). Grade 3 or 4 toxicities of mucositis were seen in 40% of the cases. Grade 1 or 2 skin toxicities were seen in all pts. Mean score of QOL in these outpatients chemotherapy was 78.0 +/- 11.5, ranked between inpatient chemotherapy (5-FU+CDDP 59.0 +/- 13.8) and oral UFT (91.8 +/- 6.1). In conclusion, this schedule of 5-FU and LV combination offers a high patient QOL and is suitable for advanced gastrointestinal cancer treatment.

Aged↗
PubMed1994

Establishment of a human thymic stromal cell line (R-3-4) and its adhesive capacity with T cells in vitro.

T cells are considered to be activated in the thymus, and it has been emphasized recently that the thymic stromal cells play an important role in the process of T-cell maturation. To clarify how the stromal cells interact with T cells a cloned stromal cell line from human thymus was established and its adhesive capacity with T cells was studied. A recombinant plasmid, pSV3gpt containing SV40 large T antigen was introduced to human thymic stroma by the calcium phosphate co-precipitation method, and the thymic stromal cell line R-3-4 was obtained. Immunohistochemical examination showed that R-3-4 possessed with HLA-class 1 antigen, laminin, fibronectin, and keratin. To determine if the R-3-4 interacts with T cells, the binding activity of R-3-4 with T cells examined by using rosette formation technique. The R-3-4 formed rosette only with the T cells, but both B cells and myeloid cells did not bind to the R-3-4. This rosette formation between R-3-4 and T cells was inhibited when T cells were pretreated with anti-CD2 antibodies, suggesting that some mechanism involving CD2 participates in this binding. Our novel established thymic stromal cell line might be useful for studying the interactions between thymic stroma and T cells in vitro.

Antibodies, Monoclonal↗
PubMed1994

[Carpal tunnel syndrome: clinical experience of 61 cases].

Carpal tunnel syndrome (CTS) is the most frequent entrapment neuropathy. Appropriate diagnosis and therapy contribute to obtaining good results. We performed carpal tunnel release in 61 patients including 8 cases with chronic renal failure. They included 18 males and 43 females. Age distribution was from 28 to 76 years of age among the males, and from 29 to 82 years of age among the female patients. Bilateral operations were performed in 13 cases (male 5, female 8). Operations were carried out with local anesthesia in all cases except one. The skin incision was about 5 cm on the palmar skin. Hypertrophy of the transverse carpal ligament was found in all cases, with a thickness of 4 mm on the average. Usually, the ligament was as hard as gum in consistency. There were also hypertrophy of the subcutaneous connective tissue and palmar aponeurosis or aberrant muscle in some cases. In CTS following long-term hemodialysis for chronic renal failure, the ligament was very hard and appeared to be partly calcified. All patients improved clinically after the operation. We should understand the characteristic clinical symptoms and signs of CTS. Clinical worsening was prominent at night and/or early in the morning. Definite diagnosis was performed by electrophysiological means. Operative indications are 1) cases whose daily activities are disturbed due to severe symptoms with progressive aggravation, 2) cases with muscle weakness in the distribution of the median nerve, 3) cases with thenar atrophy, 4) cases which, electrophysiologically, are suspected of demyelination of the median nerve. As there were many unpredictable anomalies and variations among the lesions, correct decompression of the median nerve under direct vision is necessary during surgery.

Adult↗
PubMed1994

Hematopoietic supportive function of human bone marrow stromal cell lines established by a recombinant SV40-adenovirus vector.

We have previously reported the establishment of a variety of human bone marrow stromal cell lines using a recombinant SV40-adenovirus vector. Using this vector, we obtained more clonal stromal cells. Here, we have characterized these cells and analyzed their capacity to support the proliferation and differentiation of hematopoietic cells. The stromal cells were cocultured with nonadherent human bone marrow cells used as hematopoietic cells. The total numbers of hematopoietic cells and CFU-GM in culture were counted every week. Two of the six stromal cell lines, AA101 and HAS303, supported the proliferation and differentiation of hematopoietic cells and CFU-GM for more than 9 weeks. Further, granulocytes, macrophages, and megakaryocytes were detected when cocultured with these cells. When hematopoietic cells were cocultured but separated from the two stromal cell lines by a 0.45-microns millipore membrane to prevent their attachment, almost all CFU-GM disappeared within 7 weeks. The supportive stromal cells produced GM-CSF and IL-6. However, other cell lines producing these humoral factors did not support hematopoietic cell proliferation for such a long time. These findings suggest that these established human bone marrow stromal cell lines will be useful, in that analysis of their supportive function in hematopoietic cell proliferation and differentiation through cell-to-cell interaction will shed some light on this area.

Adenoviridae↗
PubMed1994

The retinoblastoma binding factor 1 (RBF-1) site in RB gene promoter binds preferentially E4TF1, a member of the Ets transcription factors family.

The tumor suppressor retinoblastoma gene product, pRB, is a well known regulator of G1/S cell cycle progression. Moreover, mutational inactivations within the retinoblastoma gene (RB) are found in many human malignant tumors, and thus, believed to be an essential step in tumor formation. The human RB gene is considered as a housekeeping gene with no characteristic TATA or CAAT elements in its promoter region, but the sequence between 206 and 185 bases upstream of the initiation codon, essential for RB promoter activity, contains putative Sp1 and ATF recognition sites. We have previously reported that point mutations in this region, causing low penetrance retinoblastomas, completely reduced RB promoter activity, and that a nuclear factor, named RBF-1 (retinoblastoma binding factor 1), could specifically bind to this sequence, overlapping Sp1 recognition sequence. We show here, that RBF-1 can recognize a specific DNA sequence, 5'-GGCGGAAGT-3', overlapping the Sp1 and ATF sites and corresponding to the consensus DNA binding site for members of Ets transcription factors family. When RBF-1 site was used for sequence specific DNA affinity purification from erythroleukemia cells, reconstitution assays, immunoblotting analysis and peptide mapping show that the two major co-purified proteins are identical to human E4TF1-60 and -53 proteins. This reveals that E4TF1 can bind to the RBF-1 site of RB gene promoter, which, thus, constitutes a new target for this member of Ets transcription factors family.

Base Sequence↗
PubMed1993

Effect of vitamin E on arachidonic acid-release in rat peritoneal macrophages.

We have previously reported on suppression of the PGE2 production in PMA- and calcium ionophore A23187-stimulated macrophages isolated from vitamin E-treated rats. To further study the mechanism, we examined the effect of vitamin E on phospholipase A2 activity in both intact macrophages and cell-free homogenates measuring the release of [14C]arachidonic acid. In macrophages from vitamin E-treated rats, arachidonic acid release in intact cells as stimulated with PMA and calcium ionophore A23187 was hardly detected. In the cell-free homogenates, increase in phospholipase A2 activity of cytosol and particulate fractions by PMA and A23187 was partially suppressed. In unstimulated macrophages, most of phospholipase A2 was recovered in the cytosol fraction. The partially purified cytosolic phospholipase A2 showed a molecular mass 95 kDa on TSK gel G3000SW gel-filtration and on Western blot analysis using anti-rabbit platelet phospholipase A2 monoclonal antibody RHY-5. The activity of cytosolic 95 kDa phospholipase A2 was not inhibited in vitro by vitamin E. From these results, it was suggested that vitamin E needs intact macrophages to suppress arachidonic acid release.

Animals↗
PubMed1993

Underwinding of DNA on binding of yeast TFIID to the TATA element.

The TATA box-binding factor TFIID is an essential component for the initiation of transcription by eukaryotic RNA polymerase II. We investigated the effect of DNA supercoiling on TFIID: promoter interactions using recombinant yeast (ry) TFIID. DNase I footprinting analysis showed that ryTFIID has a higher affinity for the adenovirus major late promoter in the negatively supercoiled state than that in the relaxed state. On the contrary, its affinity for the Drosophila hsp70 promoter is constant irrespective of DNA topology. Binding of ryTFIID to these promoters induced underwinding of duplex DNA. The functional TATA box and active ryTFIID are essential for the underwinding. The step was facilitated by negative supercoiling of DNA on the adenovirus major late promoter but not on the Drosophila hsp70 promoter.

Animals↗
PubMed1993

Novel 8-base pair sequence (Drosophila DNA replication-related element) and specific binding factor involved in the expression of Drosophila genes for DNA polymerase alpha and proliferating cell nuclear antigen.

Upstream regions containing a novel common 8-base pair (bp) palindromic sequence, 5'-TATCGATA (Drosophila DNA replication-related element (DRE)), are required for the high expression of Drosophila genes for DNA polymerase alpha and the proliferating cell nuclear antigen (PCNA) (an auxiliary protein for DNA polymerase delta). Three DREs and one DRE are present in the DNA polymerase alpha gene (nucleotides-217, -83, and -30 with respect to the transcription initiation site) and in the PCNA gene (nucleotide-100), respectively. Deletions or 2-bp insertional mutations of DRE sequences led to an extensive reduction of promoter activities of both genes. Chemically synthesized oligonucleotides containing DRE sequences greatly stimulated the activity of the heterologous promoter of the Drosophila metallothionein gene, in addition to the promoter of the PCNA gene, when they were placed upstream from these promoters in a normal or a reverse orientation. The stimulatory effect increased synergistically and depended on the number of DREs. DRE activated the promoter when placed within 1.4 kilobases upstream from the promoter, but was much less active when placed 2.5 kilobases or more apart from the promoter. Using a gel mobility shift assay method, we obtained evidence for a protein factor (DREF) in the nuclear extract of cultured Drosophila cells (Kc cells), and this factor specifically binds to DREs of both genes. DNase I footprinting analysis indicated that DREF binds to the 24-bp DRE region of the DNA polymerase alpha gene in which 8-bp palindromic sequences are centered. A UV cross-linking experiment revealed that a polypeptide of approximately 90 kDa in the nuclear extract interacts directly with the DRE sequence. Using DRE-conjugated latex particles, DREF was affinity-purified from the Kc cell nuclear extract. By comparing results obtained by SDS-polyacrylamide gel electrophoresis and gel mobility shift experiments, we concluded that DREF is associated with the 86-kDa polypeptide. On gel filtration chromatography, a single peak of DREF activity was recovered in fractions corresponding to a molecular mass of 170 kDa, and the 86-kDa polypeptide was detected only in the corresponding fractions; thus, active DREF is probably a homodimeric form of the 86-kDa polypeptide. DREF may play important roles in coordinating expressions of Drosophila DNA replication-related genes.

Animals↗
PubMed1993

Diversification in the concept of "birth and death": the controversy about "brain death and organ transplantation" in Japan.

There is a lot of hesitation in Japan in defining brain death as the death of the individual and in proceeding to organ transplantation. Regarding the diagnostic criteria of brain death, those issued by the Japanese Ministry of Health and Welfare in 1985 are sufficient for judgment of brain death. Many people, however, do not accept brain death as death of the individual, and even those who admit brain death as death of the individual hesitate to approve of the actual removal of organs from brain dead patients. Thus, the controversy about brain death in Japan appears to be separated from the objective of organ transplantation.

Brain Death↗