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Biomedical subjects

H Moriyama

Publications and source records attributed to H Moriyama.

At least 181 records · Page 10Linked to original sources
PubMed1994

Adoptive immunotherapy mediated by anti-TCR/IL-2-activated tumour-draining lymph node cells.

The adoptive immunotherapy of cancer with sensitized T lymphocytes is well documented in several animal models. These studies indicate the existence of precursor lymphocytes, in the tumour-bearing animals, which can acquire therapeutic efficacy after in vitro manipulations. To generate immune effector cells, these precursor lymphocytes have to be antigenically stimulated in vitro by the tumour of origin. Using the weakly immunogenic MCA 205 and MCA 203 murine sarcomas, we demonstrate here that this in vitro antigenic stimulation can be achieved by sequential activation with anti-T-cell receptor (TCR) monoclonal antibody and interleukin-2 (IL-2). The culture of tumour-draining lymph node (TDLN) cells with anti-TCR/IL-2 resulted in an up to eightfold increase in cell numbers. The adoptive transfer of these activated cells mediated a significant reduction of 3-day established pulmonary metastases. Although this antibody could activate all of the TCR alpha beta-bearing T cells non-specifically, the therapeutic efficacy mediated by anti-TCR/IL-2-activated cells was tumour specific. Treatment of MCA 205 advanced pulmonary metastases resulted in prolongation of survival, and 30% of treated mice were tumour free for more than 90 days. These tumour-free mice rejected a challenge of MCA 205 but not MCA 203, indicating the development of long-lasting systemic tumour immunity. In spite of their in vivo anti-tumour efficacy, the anti-TCR/IL-2-activated TDLN cells did not exhibit detectable in vitro cytotoxicity. These results demonstrate that this activation method could be an alternative way to generating potent anti-tumour effector T cells.

Animals↗
PubMed1993

Enigmatic double-stranded RNA in Japonica rice.

We have found a linear, 16 kb, double-stranded RNA (dsRNA) in symptomless Japonica rice (Oryza sativa L.) that is not found in Indica rice (Oryza sativa L.). The dsRNA was detected in every tissue and at every developmental stage, and its copy number was approximately constant (about 20 copies/cell). Double-stranded RNA was also detected in two strains of Oryza rufipogon (an ancestor of O. sativa). Hybridization experiments indicated that the dsRNA of O. rufipogon was homologous but not identical to that of O. sativa. The sequence of about 13.2 kb of the dsRNA was determined and two open reading frames (ORFs) were found. The larger ORF (ORF B) was more than 12,351 nucleotides long and encoded more than 4,117 amino acid residues.

Base Sequence↗
PubMed1993

Genetic mapping of bfmA mutation causing fatty acid deficiency in Bacillus subtilis.

Bacillus subtilis strain 626, defective in the bfmA gene, is a derivative derivatives of B. subtilis strain 168 and requires branched short-chain carboxylic acids for growth. Branched-chain 2-keto acid decarboxylase activity and fatty acid synthesis in B. subtilis strain 626 were 14 and 7%, respectively, of their levels in strain 626-2R, a spontaneously reverted strain. These results indicate that the bfmA mutation is in either the branched-chain 2-keto acid decarboxylase gene itself or its controlling gene. Thus, primer synthesis from the 2-keto acid substrate in strain 626 is defective, causing a deficiency in fatty acid synthesis. A bfmA mutation was transferred to a suitable genetic background and analysed. The bfmA strain, CAC1, was competent and motile, and required 50 microM CaCl2 or 5 microM FeCl3 for growth on glucose minimal agar plates. The bfmA gene was mapped between glyC (320 degrees) and ctrA (325 degrees) and estimated to be at 320 degrees by protoplast fusion and PBS1 phage transduction.

Bacillus subtilis↗
PubMed1992

Site-directed mutagenesis at aspartate and glutamate residues of xylanase from Bacillus pumilus.

To elucidate the reaction mechanism of xylanase, the identification of amino acids essential for its catalysis is of importance. Studies have indicated the possibility that the reaction mechanism of xylanase is similar to that of hen's egg lysozyme, which involves acidic amino acid residues. On the basis of this assumption, together with the three-dimensional structure of Bacillus pumilus xylanase and its amino acid sequence similarity to other xylanases of different origins, three acidic amino acids, namely Asp-21, Glu-93 and Glu-182, were selected for site-directed mutagenesis. The Asp residue was altered to either Ser or Glu, and the Glu residues to Ser or Asp. The purified mutant xylanases D21E, D21S, E93D, E93S, E182D and E182S showed single protein bands of about 26 kDa on SDS/PAGE. C.d. spectra of these mutant enzymes show no effect on the secondary structure of xylanase, except that of D21E, which shows a little variation. Furthermore, mutations of Glu-93 and Glu-182 resulted in a drastic decrease in the specific activity of xylanase as compared with mutation of Asp-21. On the basis of these results we propose that Glu-93 and Glu-182 are the best candidates for the essential catalytic residues of xylanase.

Aspartic Acid↗
PubMed1992

Mucoceles of ethmoid and sphenoid sinus with visual disturbance.

In the period from 1980 through 1989, we treated 25 (20 postoperative and five primary) cases of mucoceles of the posterior ethmoidal sinus and/or sphenoidal sinus accompanied by visual disturbances. The postoperative mucocele developed 15 to 25 years after initial surgery. Manifestations of mucoceles include headache, ophthalmalgia, double vision, and exophthalmos in addition to a decrease in visual acuity. The degree of improvement in visual acuity after an operation depends on visual acuity before the operation, the mode of development of the mucocele, and the time from onset of the disease until surgery. Opening the mucocele by an endonasal approach using an endoscope is recommended as the radical form of therapy.

Adolescent↗
PubMed1992

Studies on mucocoeles of the ethmoid and sphenoid sinuses: analysis of 47 cases.

Forty-seven mucocoeles of the ethmoid and/or sphenoid sinuses (33 males, 14 females) were operated on during the 10-years period from 1980 through 1989. Thirty-seven cases were post-operative mucocoele, while the remaining 10 were so-called primary mucocoeles. None of the cases had a history of facial trauma. In the majority of post-operative cases, the mucocoele develops 15-24 years after initial surgery. Paranasal sinus surgery in young patients (teenagers) may lead to a mucocoele due to post-operative scarring in the surgical wound. The principal symptoms include globe displacement, double vision, headache, deep orbital pain, a mass in the supero-medial quadrant of the orbit, visual disturbance, etc. Sufficient opening of the mucocoele wall by the endonasal approach is recommended for surgical treatment of ethmoidal and sphenoidal mucocoeles.

Adolescent↗
PubMed1992

Crystallization and preliminary X-ray studies of a Bacillus subtilis and Thermus thermophilus HB8 chimeric 3-isopropylmalate dehydrogenase and thermostable mutants of it.

A new type of chimeric 3-isopropylmalate dehydrogenase (2T2M6T) was produced by expressing the fused gene of Bacillus subtilis and Thermus thermophilus. The enzyme shows heat stability intermediate between those of the parents. The crystal of the enzyme belongs to the space group of P3(2)21, with cell dimensions of a = b = 78.9 A and c = 158.9 A. Two thermostable mutants of the chimeric enzyme were prepared by site-directed mutagenesis and then crystallized.

3-Isopropylmalate Dehydrogenase↗
PubMed1991

Determination of serum cortisol by reversed-phase liquid chromatography using precolumn sulphuric acid-ethanol fluorescence derivatization and column switching.

An assay method for serum cortisol, using precolumn sulphuric acid-ethanol fluorescence derivatization and reversed-phase liquid chromatography with a column-switching technique, has been developed. The crude precolumn fluorescence cortisol derivative was prepared by the addition of sulphuric acid to serum deproteinized with ethanol, and directly injected onto an octadecylsilane-bonded silica gel (ODS) precolumn for concentration and purification. After switching columns the samples were separated using an ODS analytical column and monitored fluorimetrically. When the pH of the mobile phase in the analytical separator decreased to 1.85, the emission wavelength of the cortisol derivative changed to 520 nm (excitation of 365 nm) and the fluorescence intensity increased. Among the sulphuric acid-ethanol derivatives of various steroids, cortisol, corticosterone and testosterone emitted fluorescence. However, their retention times differed from those of the cortisol derivatives (12.5 min). The detection limit of cortisol was 0.3 micrograms/dl (signal-to-noise ratio of 3). Use of the fully automated column-switching system contributed to good reproducibility and recovery.

Chromatography, High Pressure Liquid↗
PubMed1991

Crystallization and preliminary X-ray studies of a Bacillus subtilis and Thermus thermophilus HB8 chimeric 3-isopropylmalate dehydrogenase.

A chimeric gene was constructed by fusing the Bacillus subtilis and Thermus thermophilus genes coding for 3-isopropylmalate dehydrogenase, and expressed in Escherichia coli. The chimeric enzyme was crystallized in a size suitable for X-ray structure analysis. The crystal has a space group of P3(1)21 or P3(2)21, a = b = 77.1 A and c = 158.3 A, which is isomorphous with that of the native enzyme from T. thermophilus.

3-Isopropylmalate Dehydrogenase↗
PubMed1991

Crystallization and preliminary X-ray studies on Sulfolobus acidocaldarius ferredoxin.

Ferredoxin from a thermoacidophilic archaebacterium, Sulfolobus acidocaldarius, has been crystallized. The space group is P4(3)2(1)2 or P4(1)2(1)2 and the cell dimensions are a = b = 50.12 A and c = 69.52 A. The Vm value is calculated to be 1.88 A3/Da, assuming one molecule per asymmetric unit. The crystal diffracts X-rays beyond 2.0 A resolution.

Crystallization↗
PubMed1991

The technique of endoscopic surgery and diagnosis of frontal recess and sinus disease under local anesthesia.

Operations are performed with the patient in a semi-reclining position under local anesthesia. Usually a rigid endoscope (70 degrees) is used for treatment of the nasofrontal-duct. Intranasal procedures are conducted in close anatomical relationship to the ground lamella in the ethmoid sinus. First, the bulla is resected through the middle meatus, then IIIgl is removed and the posterior ethmoid sinus is opened. The upper part of the ethmoid sinus is removed, and then infundibular cells connected to the naso-frontal-duct are cleared and communication with the frontal sinus is enlarged using special forceps. The lateral wall at this portion curves outward superiorly and the roof curves upward anteriorly, and it is necessary that this area be made as smooth as possible. Most cases of suppurative frontal sinusitis are curable just by opening nasofrontal-duct via endonasal approach using an endoscope.

Anesthesia, Local↗
PubMed1991

Endoscopic endonasal sinus surgery. Approaches and post-operative evaluation.

Recently, by using a rigid endoscope and a VIDEO system (CCD camera and TV monitor) for endonasal sinus surgery, surgical complications have been prevented. This is because a decrease in the dead angles achieves wide and clear visualisation of the site of manipulation of the paranasal sinuses, which have a delicate and complicated structure. Our endonasal sinus procedures under local anaesthesia consist of removal of pathologic mucosa within the anterior and posterior ethmoid sinuses, opening of the cellulae and establishment of sufficient communication between the ethmoid sinus and the maxillary and frontal sinuses. Even if pathologic mucosa is present in the maxillary sinus, we leave it intact and attempt to heal it by achieving good ventilation. The surgical technique often includes correction of septal deviations and conchotomy. In patients with moderate to severe sinusitis (62 cases, 102 examples) who underwent endoscopic endonasal sinusectomy by the same surgeon, X-ray studies of post-operative changes of the maxillary sinus were performed. Fifteen cases showed excellent results, 47 good results, 30 fair results and 10 were unchanged. Clinical symptoms exhibited an overall improvement rate of 73%. Improvement of nasal discharge and nasal obstruction was more easily achieved than improvement of post-nasal discharge.

Anesthesia, Local↗
PubMed1990

Nucleotide sequences of the Bacillus subtilis flaD locus and a B. licheniformis homologue affecting the autolysin level and flagellation.

A DNA fragment containing the flaD locus of Bacillus subtilis, which had been cloned into plasmid pAC3, was subcloned into an M13 phage and sequenced. The sequence contained five open reading frames (ORFs), of which ORF2 was the flaD gene. Unexpectedly, the sequence of the flaD locus was identical to that of sin [sporulation inhibition gene; Gaur, N. K., Dubnau, E. & Smith, I. (1986). Journal of Bacteriology 168, 860-869]. A B. licheniformis homologue (flaL) of the B. subtilis flaD locus was cloned into pUC19 and identified by colony hybridization. The B. licheniformis DNA was subcloned and sequenced. Two ORFs (ORF1, or L-ORF1; and ORF2, or flaL) were detected, encoding 58 and 111 amino acid residues, respectively. These are almost identical in length to ORF1 (D-ORF1; 57 amino acids) and flaD (111 amino acids) on the fragment of B. subtilis DNA. The overall interspecies differences between the nucleotide sequences of D-ORF1 and L-ORF1, and those of flaD and flaL, were 42% and 11%, respectively, and the differences in the predicted amino acid sequences were 50% and 7%, respectively. The regions 3' of the ORFs (flaL and flaD) in both species resemble rho-independent terminators of transcription. The characteristics of the amino acid sequences are also discussed.

Amino Acid Sequence↗
PubMed1990

A new apparatus for brain imaging: four-head rotating gamma camera single-photon emission computed tomograph.

The development of a new rotating gamma camera SPECT device for imaging the brain was undertaken with the objective of achieving the highest full volume imaging spatial and temporal resolution performance. For this purpose, four rectangular gamma camera detectors were arranged as close to the head as possible, and united in a block to insure detector head registration and alignment as well as to enable rotation stability at high speeds. Phantom and clinical studies performed demonstrated 42 sequential, 4-mm thick transaxial images acquired in one scan and with sufficient volume to permit the entire cerebrum and cerebellum to be imaged with high sensitivity. The central field of view reconstructed spatial resolution measured 7.0 mm full width of half maximum utilizing the high-resolution collimator, and tomographic images of arbitrary planes including sagittal and coronal demonstrated equally high resolution. The high sensitivity and high speed rotational acquisition capability of the device permits dynamic SPECT studies to be carried out in the analysis of rapidly varying radiotracer concentrations.

Brain↗
PubMed1989

The solubility and colloidal behaviour of neptunium (IV).

The solubility and colloidal particle formation of Np(IV) in 10(-1) M Na2S2O4 solution in the pH range 2-10 were studied by sequential filtration with decreasing filter pore size. With the help of spectrophotometry and an extraction technique, the species remaining in the final filtrate were found to be Np(V) at pH less than 6 and Np(IV) at pH greater than 8; particle species were attributed to Np(IV). The solubility data obtained at pH less than 6 were interpreted using the reaction: Np(OH)4(am)----NpO2+ + e- + 2H2O, log K = -6.7 +/- 0.4 At pH greater than 8, the solubility increased rapidly with increasing pH in the presence of air, and this was interpreted as being due to the formation of the negatively charged species Np(CO3)4x - 2x. The formation constants beta 3 and beta 4 were estimated to be similar to those reported for Pu(IV). The size distribution of colloidal Np(IV) was also obtained. Some simple models used to describe the observed size distributions and to estimate the equilibrium size distributions of colloidal Np(IV) were examined.

Colloids↗