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M Wakita

Publications and source records attributed to M Wakita.

At least 19 recordsLinked to original sources
PubMed1995

Analysis of the sequence of a new cryptic plasmid, pRJF2, from a rumen bacterium of the genus Butyrivibrio: comparison with other Butyrivibrio plasmids and application in the development of cloning vector.

A small cryptic plasmid, pRJF2, from Butyrivibrio fibrisolvens strain OB157 was isolated and sequenced. The plasmid is similar in organisation to the previously sequenced Butyrivibrio plasmid, pRJF1, with two open reading frames, ORF1 and ORF2, flanking a region tentatively identified as the replication origin, and a region of unknown function defined by terminal 79 bp invert repeats. The sequences of ORF1, ORF2, and the presumptive replication origin are highly conserved. The sequence between the 79, bp invert repeats is not, and is therefore presumed to be of lesser functional significance, although the 5' and 3' termini are still highly conserved. The functional importance for plasmid replication of these regions was tested by constructing potential shuttle vectors, each lacking one or more of the regions of interest. When the region between the invert repeats was deleted and replaced by the erythromycin resistance gene from pAM beta 1 together with pUC18, to produce the 7.9 kb chimaeric plasmid pYK4, the construct was successfully transformed into E. coli and B. fibrisolvens by electroporation, and was stably maintained in both hosts. Both ORF1 and ORF2 were required for successful transformation of B. fibrisolvens.

Amino Acid Sequence↗
PubMed1995

Interleukin-1 beta (IL-1 beta) and acute leukemia: in vitro proliferative response to IL-1 beta, IL-1 beta content of leukemic cells and treatment outcome.

We evaluated the in vitro proliferative response to exogenous IL-1 beta in terms of tritiated thymidine (3H-TdR) incorporation in leukemic cells obtained from 119 patients with various types of acute leukemia. The content of IL-1 beta in leukemic cells was measured by enzyme-amplified sensitivity immunoassay. We observed a significant proliferative response to exogenous IL-1 beta in leukemic cells from 27/66 patients with de novo AML, 1/29 patients with ALL, 2/3 patients with AUL, 8/12 patients with AML arising from MDS, 4/7 patients with myeloid crisis of CML, and 0/4 patients with lymphoid crisis of CML. Proliferation was marked in myeloid leukemic cells of a more premature stem cell origin. There were no significant differences in proliferative responses among the different FAB classes of de novo AML. The IL-1 beta content of leukemic cells was low in patients with lymphoid leukemia, but there was no significant difference among the various types of myeloid leukemia. There was no correlation between the proliferative response to exogenous IL-1 beta and the IL-1 beta content of leukemic cells. When we correlated the proliferative response to exogenous IL-1 beta with treatment outcome in patients with de novo AML, we found the rate of complete remission (CR) to be lower in those with a high proliferative response. We noted a longer duration of CR (p = 0.07) and of survival (p < 0.05) in patients with a low proliferative response. Thus, a high proliferative response to IL-1 beta in the cells of AML patients may indicate a poor prognosis.

Acute Disease↗
PubMed1994

Electron microscopic and histochemical studies of the mononuclear odontoclast of the human.

BACKGROUND: Osteoclasts and odontoclasts are multinucleated giant cells which resorb hard tissue by the ruffled borders. Recently, the authors reported the presence of a mononuclear osteoclast with a ruffled border in vitro. However, its presence in vivo has not been shown. To demonstrate the presence of a mononuclear odontoclast in humans, the present study used human deciduous teeth. METHODS: After fixation and decalcification, tartrate-resistant acid phosphatase (TRACPase) activity was detected with the azo dye method, and then TRACPase-positive cells were observed on resorbing areas of teeth. TRACPase-positive cells could be distinguished from other cells by light microscopy, and the cells for investigation were serially sectioned by alternating semithin and ultrathin sections to observe their ultrastructure and three-dimensional organization. RESULTS: TRACPase activity was detected in both multinucleated odontoclasts and a mononuclear cell from serial sections. By electron microscopy, most of the multinucleated odontoclasts had ruffled borders and clear zones. A mononuclear TRACPase-positive cell with a ruffled border and clear zone was reconstructed three-dimensionally by NIKON COSMO-ZONE 2SA. The reconstruction showed that this cell had one irregularly shaped nucleus and a wide ring-shaped clear zone and a small ruffled border. Under the ruffled border, this cell formed a small lacuna on the dentin surface. The results suggested that this cell was a mononuclear odontoclast. CONCLUSIONS: The present study concludes that cells with ruffled borders and clear zones observed by transmission electron microscopy can be identified as odontoclasts or osteoclasts irrespective of the number of nuclei.

Acid Phosphatase↗
PubMed1994

Comparative study of the initial genesis of acellular and cellular cementum in rat molars.

The initial genesis of acellular and cellular cementum was examined in rat molars by light and electron microscopy. Before root dentinogenesis, flattened dental follicle cells formed compartments by regularly arranged cellular processes which demarcated collagen fibril bundles oriented in parallel with the root long axis in both of the two kinds of cementum. After this stage, compartments disappeared from the dental follicle cells, which became elongated and polarized, with the cytoplasmic side facing toward the root surface in the acellular cementogenesis. Fibril bundles, oriented in parallel with the root long axis, decreased in number, and principal fibers appeared. Some principal fibers were attached on the first acellular cementum. Observations suggested that the fibril bundles, which had been oriented in parallel with the root long axis, were reoriented to merge into the principal fibers. In cellular cementogenesis, the dental follicle cells continued to hold the fibril bundles in cellular compartments. The regular processes were transformed into randomly oriented, finger-like processes. At the same time, fibers, which may be secreted from the finger-like processes, appeared around the preformed fibril bundles oriented in parallel with the root long axis. The different cellular behavior may result in the different fiber arrangement of acellular and cellular cementum.

Age Factors↗
PubMed1994

Lysis of autologous tumor cells by large granular lymphocytes in patients with acute leukemia in complete remission: correlation between lytic activity and clinical outcome.

In order to evaluate the effect of specific immune response on prognosis in acute leukemia, we investigated the correlation between the lysis of autologous tumor cells (ATC) by lymphocytes and prognosis. Peripheral mononuclear cells (PMC) from most patients with acute leukemia in complete remission (CR) do not exhibit cytotoxic activity against fresh-frozen ATC, although they have adequate cytotoxic activity against K562 cells. When the large granular lymphocyte (LGL) fraction was used in this study, we observed lysis of ATC in 17 (43.6%) of 39 patients with acute leukemia (12 (42.9%) of the 28 patients with acute myelogenous leukemia (AML) and 5 (45.5%) of the 11 patients with acute lymphocytic leukemia (ALL)). With regard to prognosis, the lytic activity of the LGL fraction did not reflect the duration of CR. The median CR duration in AML patients was 13 months for the lysis-positive group and 11 months for the lysis-negative group. No significant correlation was also found between lytic activity of the LGL fraction and overall survival in each patient. However, the lysis-positive group tended to have a longer survival, the median overall survival being 48 months for the lysis-positive group vs 12 months for the lysis-negative group. The prolonging of overall survival in the lysis-positive group was attributed to a high rate of induction of second remissions in this group. Long-term patient survival in the two groups did not differ.

Adolescent↗
PubMed1994

Translocation (3;21)(q26;q22) in treatment-related acute leukemia secondary to acute promyelocytic leukemia.

We performed cytogenetic studies in a patient with treatment-related acute leukemia (t-AL) to identify the associated chromosomal changes. Metaphase analysis revealed a t(3;21)(q26;q22) translocation. Acute promyelocytic leukemia (APL) had been diagnosed 4 years earlier and the patient had received intensive induction chemotherapy and sequential post-induction therapy that included agents that targeted DNA-topoisomerase II (topo II). This case suggests an association between previous therapy with topo II inhibitors and development of t-AL associated with a balanced aberration involving the 3q26 and 21q22 bands.

Acute Disease↗
PubMed1994

Effects of 3 chemical treatments on in vitro fermentation of rice straw by mixed rumen microbes in the presence or absence of anaerobic rumen fungi.

Rice straw (Rs) was treated by a sodium chlorite/acetic acid mixture (Sct), ammoniation (At) and alkaline hydrogen peroxide (Athp) methods. The objective was to compare their degradation and fermentation products in the presence or suppression of anaerobic fungi. Significant differences (P < 0.01) in degradation of straws were observed during all periods of incubation with Sct having the highest digestibilities during the 48-h and 72-h incubations. The degradation of Sct straw was highest in both of the incubations with whole rumen fluid (WRF) and WRF plus cycloheximide. In sacco digestion followed the order of Sct > At > Rs > Athp. Suppressing fungal activity with cycloheximide resulted in a decrease in dry matter degradation, with concomitant decrease in total volatile fatty-acid concentration. While the suppression of fungal activity with cycloheximide depressed acetate and butyrate production, it favored an increase in propionate production.

Acetates↗
PubMed1994

Interaction between dibucaine and pig erythrocyte membranes as studied by NOESY experiments in 1H-NMR spectroscopy. Which form of dibucaine interacts more strongly, cationic or uncharged?

The interaction between amine local anesthetic dibucaine and pig erythrocyte membranes has been studied by 1H-NMR spectroscopy. Two-dimensional NOESY spectra were observed to obtain the conformations of cationic and uncharged forms of dibucaine. The NMR spectra were measured at pH 7.4, and the temperature was raised (318-348 K) to increase the concentration of the uncharged form of dibucaine, taking the temperature dependence of the pKa value of dibucaine into consideration. The dibucaine in a buffered solution showed the presence of two kinds of distinctly different species; one is assignable to the cationic form and the other to the uncharged form of dibucaine, suggesting that the protonation equilibrium between the two forms is slow in the presently employed experimental condition. The uncharged dibucaine showed well-defined NOE cross-peaks in the NOESY spectra of the solution containing no erythrocyte membranes, suggesting that its conformation is relatively fixed. Interestingly, however, it was only the cationic dibucaine that showed NOE cross-peaks when the solution contained the membranes, and experiments were performed at a much shorter mixing time for the buildup of NOEs, suggesting that it appeared only the cationic form of dibucaine is interacting with the membranes. It was concluded that the uncharged form of dibucaine, which was produced by raising the temperature, formed micelles in a buffered solution. Thus formed micelles didn't interact with membranes owing to the repulsive forces between the structured water surrounding the micelles and those at the surface of the membranes. This conclusion could be a promising reason why the cationic local anesthetics are much more active than their uncharged counterparts in blocking nerve conduction.

Animals↗
PubMed1994

The three-dimensional structure of Tomes' processes and their relationship to arrangement of enamel prism in dog teeth.

The relationship between the course of enamel prisms and the direction of secretory face in Tomes' process of ameloblast was examined three-dimensionally in the dog tooth by light and electron microscopy, as well as by reconstruction. Scanning electron microscopic observation on the developing enamel surface after the dissolution of the enamel organ showed numerous groups of pits with bulbous faces inclined in the same sidewards direction, while those faces in neighboring groups were inclined in an opposite direction. Tangential semithin sections from demineralized tooth germs were serially cut from the enamel surface to the enamel-dentin junction. These sections showed numerous belt-like zones arranged perpendicular to the meridian of the tooth. A straight row of enamel prisms perpendicular to the boundaries of the belt-like zones was selected at 142 microns from the enamel-dentin junction. The row of prisms and their successive Tomes' processes were reconstructed from micrographs with a personal computer. The cut ends of the enamel prisms initially perpendicular to the boundaries appeared as a sine curve, viewed from the enamel-dentin junction. In a single belt-like zone, the horizontal tilt angles of the enamel prisms towards the enamel-dentin junction tended to be largest at the center of the zone, and smallest near the boundaries. The long axis of each enamel prism was at right angles to the secretory face of the Tomes' process. The secretory faces in a single belt-like zone were inclined in the same sidewards direction and the secretory faces in neighboring zones were inclined in opposite directions. The results suggest that the direction of the sidewards displacement in ameloblasts is related to that of the secretory face of Tomes' processes. Further, one group of ameloblasts with their secretory faces inclined in the same sidewards direction form one belt-like zone.

Ameloblasts↗
PubMed1994

Cytokeratin expression during regeneration of the intralobular duct in rat submandibular glands after YAG laser irradiation.

Changes in the expression of cytokeratin subunits during regeneration of the intralobular duct in partially injured rat submandibular glands were investigated. Limited parts of rat submandibular glands were injured by irradiation with YAG laser. Irradiated glands were investigated histologically and immunohistochemically using anti-cytokeratin monoclonal antibodies, RCK105 and CK19. Irradiated areas became necrotic one day after YAG laser irradiation. At three and five days, duct-like structures and epithelial clusters began to regenerate at the periphery of the remaining lobule. Epithelial clusters without ductal spaces were situated at the terminal portion of the duct-like structures. At seven and ten days, duct-like structures were composed of cuboidal or low columnar cells, and the number of epithelial clusters decreased. Immunohistochemically, cells of intralobular ducts in normal rat submandibular glands reacted to RCK105 and CK19. At three and five days, the epithelial cells of duct-like structures were positive for both antibodies. Many cells in the epithelial clusters showed negative reaction. However, in some epithelial clusters, inner cells and cells facing narrow luminal spaces were positive for both antibodies. At seven and ten days, positive reaction for both antibodies was identified in duct-like structures. This study showed that cells of the epithelial cluster were less mature than those of the duct-like structure, and that in the epithelial cluster, the inner cells were the first to differentiate into intralobular ductal cells.

Animals↗
PubMed1994

[CAMBO-VIP for advanced diffuse large cell lymphoma (LSG classification)--a long-term follow-up study].

Twenty-two patients with advanced diffuse large cell lymphoma (LSG classification) were treated with the combination chemotherapy of cyclophosphamide, doxorubicin, methotrexate with leucovorin rescue, bleomycin, vincristine, etoposide, ifosfamide and prednisolone (CAMBO-VIP) from Oct. 1987 to Sept. 1989. Eighteen (90%) of 20 evaluable patients achieved complete remission and 2 patients had partial remission. With a median follow-up of 52 mos, 3 patients relapsed (17%), and 2 patients died. The actuarial overall survival and relapse-free survival at 4 years were estimated to be 90% and 83%, respectively. Myelosuppression was severe, but transient. No serious infection was seen, and no platelet transfusion was required. Oral mucositis and liver damage (Grade 3 in WHO grading) was seen in one patient each, but no treatment-related fatalities were observed. CAMBO-VIP is a well tolerated, effective treatment regimen for advanced diffuse large cell lymphoma.

Adolescent↗
PubMed1994

[Increased blood cell destruction during vigorous regeneration of bone marrow after CAMBO-VIP chemotherapy for non-Hodgkin's lymphoma].

Alternating non-cross-resistant chemotherapy has been induced for the treatment of non-Hodgkin's lymphoma (NHL) with the aim of cure, even in advanced cases. We formulated a new high dose regimen, CAMBO-VIP, which was a weekly treatment. They were administered during alternate weeks for a total period of 12 weeks. We obtained high response rate and prolonged disease-free survival with this regimen. We noticed the elevation of serum LDH level in some patients at or shortly after the completion of CAMBO-VIP treatment. LDH elevation was not associated with liver function abnormality in terms of elevation of GOT or total bilirubin. All of these patients were in complete or partial response with no evidence of tumor progression. An LDH isozyme study which was done at the time of LDH elevation showed elevation of both LDH1 and LDH2. Interestingly serum haptoglobin was undetectable in all 6 patients measured at the time of LDH elevation. Reticulocytosis and leukoerythroblastosis in peripheral blood were also observed in all of these patients. These abnormalities including LDH elevation returned to normal within a rather short period, usually within 1 to 3 weeks. From these observations, it is most likely that these abnormalities were due to excessive blood cell destruction, which was observed in association with rapid recovery from myelosuppression.

Adolescent↗
PubMed1994

[Salvage chemotherapy for relapsed/refractory aggressive non-Hodgkin's lymphoma with a combination of dexamethasone, etoposide, ifosfamide and carboplatin].

Seventeen patients with refractory or relapsed, intermediate or high grade non-Hodgkin's lymphoma (NHL) were treated with the combination of dexamethasone (40 mg/body x 3d, iv) (DeVIC) between January and December 1992. The treatments were repeated every three weeks for a minimum of two courses unless the patient had PD. G-CSF (2 micrograms/kg, sc) was given during leukopenia in most cases. Of 16 evaluable patients 6 (38%) achieved a complete remission (CR) and 4 showed a partial remission. With median follow up of 15 (7-26) months (mos.) all CR patients were alive in CR, except for 1 patient who died of secondary AML. The actuarial 50% survival duration after DeVIC was 15+ mos. One patient died of sepsis but myelosuppression was generally moderate and no other serious toxicity was observed. Although this is a preliminary study, DeVIC regimen seems to be an effective salvage therapy for patients with refractory or relapsed NHL with acceptable toxicity.

Adolescent↗
PubMed1993

Calcium-dependent changes in structure of calmodulin with substance P.

Solution x-ray scattering using synchrotron radiation as an x-ray source has been used to study the solution structure of calmodulin complexed with substance P, a undecapeptide neurotransmitter. The x-ray data indicate that the complex has a compact globular structure, the formation of which is dependent upon the binding of Ca2+ to calmodulin. In the Ca(2+)-saturated condition, the radius of gyration of complexed calmodulin was 4.2 A smaller than that of uncomplexed calmodulin. The Ca(2+)-dependent change in radius of gyration of calmodulin with substance P is complete by the third and fourth Ca2+ binding. The behavior of the Guinier plot at small-to-moderate angles for uncomplexed calmodulin corresponds to a dumbbell shape. The Guinier plot for complexed calmodulin, however, corresponds to a non-dumbbell shape. The susceptibility of calmodulin to proteolytic attack with trypsin was used to examine the nature of the calmodulin complexed with substance P. In the presence of equimolar substance P, the first and second Ca2+ binding to calmodulin was enough to form a trypsin-resistant complex. These biochemical and x-ray data suggest that the binding of substance P to calmodulin is completed when the C-terminal half of calmodulin is occupied by Ca2+, while a significant structural change of calmodulin in the complex is still induced by successive Ca2+ occupancy on the N-terminal half of this molecule.

Amino Acid Sequence↗
PubMed1993

Expression of a novel human homeobox-containing gene that maps to chromosome 7q36.1 in hematopoietic cells.

A homeobox is a DNA sequence of 180 base pairs that encodes a DNA-binding domain known as a homeodomain. The polymerase chain reaction (PCR) has been used to prepare probes of homeobox-containing genes. We cloned and sequenced the amplified products of PCR that was performed with human genomic DNA and two primers that correspond to well-conserved regions in homeoboxes. Fifteen kinds of homeobox gene were identified and 13 of them were assigned to HOX genes that have already been reported. Two others represented novel homeobox genes and one of them, GBX1, was mapped to chromosome 7q36.1 by fluorescence in situ hybridization. Northern hybridization of mRNA for various kinds of hematopoietic cell showed that the newly identified GBX1 gene is expressed in K562 cells and Daudi cells.

Amino Acid Sequence↗
PubMed1993

Effect of hypophysectomy on insulin-like growth factor (IGF)-1 binding activity of serum in chickens.

1. Hypophysectomy elevated IGF-1 binding activity of serum concurrently with decreases in circulating concentrations of IGF-1 and growth hormone (GH). 2. When sera pooled from each experimental group were chromatographed on a Sephadex G-200 column, IGF-1 binding activity was mainly found in 150 and 30 kilodalton (kDa) proteins. 3. Most of the serum IGF-1 were distributed among 150 kDa protein fractions. 4. Hypophysectomy elevated IGF-1 binding activity of these proteins, especially that of 30 kDa protein. 5. The binding of [125I]IGF-1 to the 30 kDa protein was inhibited by unlabelled IGF-1 but not by insulin, and saturated with a small amount of the ligand compared to the 150 kDa protein. 6. The IGF-1 binding activity of 30 kDa protein was dependent on GH status of chickens.

Animals↗
PubMed1993

Effects of thyroxine supplement on serum insulin-like growth factor-binding activity in propylthiouracil induced hypothyroid cockerels.

In propylthiouracil (PTU)-fed (g/kg feed) hypothyroid cockerels, serum levels of growth hormone (GH), but not insulin-like growth factor (IGF)-1, tended to rise and those of IGF-binding activity to fall. Thyroxine (T4) supplement (200 micrograms/kg/day) to PTU-fed cockerels for 8 days produced a hyperthyroid state and reversed these serum parameters. A chromatographic analysis of serum proteins revealed that T4 supplement markedly enhanced the IGF-binding activity of a 30 kDa protein and slightly lowered that of a 150 kDa protein, suggesting that T4 increases unsaturated IGF-binding proteins by reducing circulating IGF-1 concentrations.

Animals↗