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H Tsubota

Publications and source records attributed to H Tsubota.

At least 19 recordsLinked to original sources
PubMed2000

Dynamical relativistic effects in quasielastic 1p-shell proton knockout from 16O

We have measured the cross section for quasielastic 1p-shell proton knockout in the 16O(e,e(')p) reaction at omega = 0.439 GeV and Q2 = 0.8 (GeV/c)(2) for missing momentum P(miss)</=355 MeV/c. We have extracted the response functions R(L+TT), R(T), R(LT), and the left-right asymmetry, A(LT), for the 1p(1/2) and the 1p(3/2) states. The data are well described by relativistic distorted wave impulse approximation calculations. At large P(miss), the structure observed in A(LT) indicates the existence of dynamical relativistic effects.

Journal Article↗
PubMed2000

Morphometric study of the medial aspect of the human maxillary sinus with special reference to the nasal fontanelle.

OBJECTIVE: The purpose of this study was to clarify configurations of the nasal fontanelle (NF) from the morphometrical point of view, especially variations of its four margins (anterior, posterior, superior, and inferior), for clinical application. METHODS: We used 136 sides of hemi-sectioned heads that were obtained from 119 donated Japanese cadavers (66 men and 53 women with an average age of 77.6+/-12.0). After mucosal examination, the specimens were boiled with a small amount of powdered soap and treated with protease. The residual mucous membrane was then gently removed. These specimens were originally made for our previous study describing variations of the uncinate process (Isobe M, Murakami G, Kataura A. Variations of the uncinate process of the lateral nasal wall with clinical implications, Clin. Anat. 1998;11:295-303). Different series of measurements were conducted based on surgical approaches and angles of observation. RESULTS: The superior margin of the NF is difficult to identify because the ethmoidal infundibulum, which leads the anterior end of the margin upward, often interrupts the superior margin. Because the inferior and posterior margins are modified by thin paper-like bony structures and because the anterior margin is disturbed by variations of the lacrimal bone and/or the inferior turbinate, they are also difficult to identify. Knowing these variables, we evaluated the NF morphometrically. The NF was located 12.6+/-4.3 mm posterior to the anterior nasal spine and 6.6+/-2.2 mm anterior to the sphenopalatine foramen. The size of the NF was 17.9+/-3.2 mm (anteroposterior axis) x 11.5+/-3.0 mm (inferosuperior axis). The lowest orbital floor was located 10 mm below the superior margin of the anterior NF (-10 mm), and the distance was therefore measured as -3.7+/-2.4 mm on average. Viewed from the maxillary sinus, the location of the NF varied along the anteroposterior axis, whereas it was located consistently at the most superior portion of the medial aspect of the sinus wall. CONCLUSION: During endoscopic sinus surgery for tumor resection in the maxillary sinus, a large and primary window should be prepared in the posterior NF, including partial removal of the uncinate process. Preparation of an additional window in the inferior meatus is preferable to enlargement of the primary window. Approaching the anterior NF should be avoided, if possible, due to its complicated configuration as well as its proximity to the orbital floor.

Aged↗
PubMed1998

A new enzymatic assay for selectively measuring conjugated bilirubin concentration in serum with use of bilirubin oxidase.

A new enzymatic assay for selectively measuring conjugated bilirubin concentration in serum with use of bilirubin oxidase (BOD) has been developed. At pH 5.5 BOD can oxidize only conjugated bilirubin in the presence of reagents such as sodium fluoride and N-acetylcysteine which can decrease BOD reactivity to unconjugated bilirubin and bilirubin covalently bound to albumin (delta bilirubin). The resulting decrease in absorbance at 450 nm is linearly related to the concentration of conjugated bilirubin in serum. The BOD in this new assay was confirmed to oxidize conjugated bilirubin, and neither unconjugated nor delta bilirubin, based on both its reactivity to unconjugated bilirubin and HPLC results. This assay was found to give satisfactory results, such as in terms of the range of measurement, the reproducibility of the results, the lack of interference with coexisting substances in serum and the stability of the reagent solutions, in practical applications. The serum conjugated bilirubin concentrations determined using this assay correlate well with those determined by the HPLC analysis. This assay can be used for accurate monitoring of changes in the conjugated bilirubin concentration in patient sera. These findings suggest that the conjugated bilirubin assay is useful for fractional determination of bilirubin in icteric sera.

Bilirubin↗
PubMed1997

Prognostic factors and treatment outcome in non-Hodgkin's lymphoma of Waldeyer's ring.

Prognostic factors and treatment outcome of 71 patients with non-Hodgkin's lymphoma of Waldeyer's ring were analyzed retrospectively. In univariate analyses, unfavorable prognosis was associated with primary disease in the base of the tongue, stage III-IV diseases, B-symptoms, high-grade histology, T-cell phenotype, elevated serum LDH levels, decreased peripheral blood lymphocyte counts, and negative response on delayed type hypersensitivity skin reactions. Multivariate analysis showed that stage III-IV and T-cell phenotype were significant independent risk factors for death. In stage I-II lymphomas, patients with unilateral large or bilateral cervical lymph node involvement had a poorer prognosis. In stage I-II lymphomas with intermediate or high-grade histology, patients who had received radiotherapy with MTCOP-P chemotherapy (pirarubicin, cyclophosphamide, vincristine, methotrexate with leucovorin rescue, peplomycin, and predonisolone) showed significantly better 5-year disease-free survival rate compared with patients treated with radiotherapy alone.

Adolescent↗
PubMed1996

Expressions of very late antigen-6 and vitronectin receptor, and their interactions to laminin and vitronectin during tonsillar B-cell activation.

This study examined the expressions of a-subunits of very late antigen-6 (VLA-6; alpha 6) and vitronectin receptor (VNR; alpha V) on tonsillar B cells and interactions between those integrins and their respective ligands, laminin (LM) and vitronectin (VN). alpha 6 and alpha V were expressed on about 30 to 40% of tonsillar B cells. When purified tonsillar B cells were separated by a discontinuous Percoll gradient, the number of alpha 6- and alpha V-positive cells decreased as the cell density went down, while the number of activated cells went up. After in vitro activation of tonsillar B cells by Staphylococcus aureus Cowan I strain (SAC), the expressions of alpha 6 and alpha V and their adhesiveness to LM or VN decreased significantly. Increased proliferation of B cells was observed when tonsillar B cells were cultured with immobilized LM or VN. The results of immunohistological staining showed VLA-6, VNR, LM and VN in the follicular area. These results suggest that the expressions of VLA-6 and VNR on tonsillar B cells may be decreased during B cell activation, and the interaction between VLA-6, VNR, and LM, VN may give a costimulatory effect on B cell activation in the follicular area of the tonsil.

Antibodies, Monoclonal↗
PubMed1996

Interaction and immunological effect of very late antigen-4, 5, and fibronectin in tonsillar lymphocytes and their relation to age.

We examined the expressions of alpha-subunits of very late antigen (VLA)-4 (alpha4) and VLA-5 (alpha5) on tonsillar lymphocytes and the interaction between these integrin receptors and their ligand, fibronectin (FN). Immunohistological and flow cytometric analyses showed that alpha4 and alpha5 were expressed in the lymphoid follicle and were positive on about 10% each of T cells and on 55% and 35% of B cells. When tonsillar B cells were separated by a discontinuous Percoll gradient, the number of alpha4- and 5-positive cells decreased as the cell density went down, while the number of activated cells went up. After in vitro activation of tonsillar B cells by Staphylococcus aureus Cowan I strain (SAC), the expression of alpha5 and the adhesiveness to FN decreased. The increased proliferation of B cells was observed when tonsillar B cells were cultured with immobilized FN. The expressions of alpha-subunits of VLA-4 and VLA-5 on tonsillar T and B lymphocytes increased with age. These results suggest that: i) B cell activation may cause decreased expressions of VLA-4 and -5, which gives a costimulatory effect on B cell activation itself again in cooperation with FN, ii) Increased expressions of VLA-4 and -5 on tonsillar lymphocytes with age may be related to regional immune response of the palatine tonsils.

Adolescent↗
PubMed1996

Clinical analyses of focus tonsil and related diseases in Japan.

Clinical analyses were performed in groups of patients with several diseases that are regarded as diseases of focus tonsils. These patients underwent tonsillectomy from 1981 to 1993 in our department. They included 289 cases of pustulosis palmaris et plantaris (PPP), 35 cases of psoriasis vulgaris (PV), 100 cases of sternocostoclavicular hyperosteosis (SCCH), and 18 cases of rheumatoid arthritis (RA). Tonsillectomy was found to significantly alleviate clinical symptoms of the above diseases as follows: 88.1% of the PPP cases, 48.6% of the PV cases, 80.9% of the SCCH cases, and 66.7% of the RA cases. Age distribution of the patients, relation between the effect of tonsillectomy and age, sex and other factors were also analyzed.

Adolescent↗
PubMed1995

Stabilized enzymatic reagents for measuring glucose, creatine kinase and gamma-glutamyltransferase with thermostable enzymes from a thermophile, Bacillus stearothermophilus.

Stabilized enzymatic reagents for measuring some components in biological fluids have been successfully developed based on two kinds of thermostable enzymes derived from Bacillus stearothermophilus with separation of the reagent into two complementary solutions. The thermostable glucokinase produced was applied to the measurement of glucose and creatine kinase activity, while the alanine dehydrogenase produced was used for the measurement of gamma-glutamyltransferase activity. The enzymatic reagents were also stabilized by developing two separate reagents with an optimum pH for the main reagent components. The stability of the reagents in liquid form was examined at 10 degrees C. It was clearly shown that the reagents for measuring glucose and creatine kinase activity were stable and retained their full capability for accurate measurement in biological fluids for over one year. The alanine dehydrogenase product was stable for at least 40 days.

Alanine Dehydrogenase↗
PubMed1994

[Tonsillectomy and osteoarthritic disease].

We investigated the clinical outcome of tonsillectomy in 89 cases out of 100 cases of sternocostoclavicular hyperosteosis (SCCH) and 18 cases of rheumatoid arthritis (RA) who went through the operation more than 3 months before in our hospital between April 1984 and May 1993. The effect of tonsillectomy was associated with a decrease in the degree of pain. The symptom improvement was defined as a degree of pain less than 50% of the pre-operative level. The rates of improvement were 80.9% (72/89) in SCCH and 66.7% (12/18) in RA, whole 79% of SCCH patients had pustulosis palmaris et plantaris, a known focal infection of the tonsil. Eight of nine (88.9%) patients and eleven of 13 (84.6%) patients who were positive for the tonsillar provocation test and the annulation test, respectively, showed improved SCCH postoperatively. These results suggest that focal infection of the tonsil may be one of the etiologies of SCCH and RA.

Arthritis, Rheumatoid↗
PubMed1994

[Efficacy of tonsillectomy for improving skin lesions of Pustulosis palmaris et plantaris--evaluation of 289 cases at the Department of Otolaryngology of Sapporo Medical University].

In recent years, Pustulosis palmaris et plantaris (PPP) has been described as one of the representative second lesions of focal tonsillitis in Japan. We selected 289 cases of PPP, treated with bilateral tonsillectomy at our department over the past 12 years for this clinical evaluation. In 211 of those 289 tonsillectomy cases, follow-up was done for more than 3 months after operation. Prior to tonsillectomy, 196 cases suffered from PPP only, 90 cases had the complication of osteo-arthral lesions such as sterno-costa-clavicular hyperosteosis (SCCH), rheumatoid arthritis, and soon, whereas only 3 cases showed simultaneous lesions of Psoriasis vulgaris. The efficacy of tonsillectomy for improving the skin lesions was classified into 6 grades, mainly based upon individual evaluation by each patient as follows; disappeared, remarkably improved, improved, slightly improved, unchanged, and worsened. According to our 211 cases, post tonsillectomy improvement of skin lesions was very obvious, with disappearance occurring in 54.3% of cases and remarkable improvement in 21.4%. Age of onset and the duration from onset to tonsillectomy showed no association with effectiveness. However, the shorter the duration from onset to tonsillectomy, the fewer days were required for improvement of the skin lesions. The rate of improvement of PPP rose in conjunction with the number of days after tonsillectomy. We conclude that it requires 12 months, at minimum, to determine the efficacy of tonsillectomy as a treatment for PPP.

Adolescent↗
PubMed1992

Assay of gamma-glutamyltransferase with amino acid dehydrogenases from Bacillus stearothermophilus as auxiliary enzymes.

A spectrophotometric assay for serum gamma-glutamyltransferase (gamma-GT, EC 2.3.2.2) based on the increasing absorbance at 340 nm due to NADH formation is described. Using gamma-glutamyl dipeptides as the donor substrate, amino acids formed by the gamma-glutamyl transfer from the donor substrate to the acceptor substrate glycylglycine are stoichiometrically converted by the corresponding amino acid dehydrogenases from Bacillus stearothermophilus to produce their keto acids and NADH. gamma-Glutamylalanine was found to be the most specific and sensitive donor substrate. The method can be mechanized, is free of interference and correlates well with conventional methods.

Amino Acid Oxidoreductases↗
PubMed1992

Regions of the CD4 molecule not involved in virus binding or syncytia formation are required for HIV-1 infection of lymphocytes.

Cell surface-expressed CD4 binds to the envelope glycoprotein of HIV-1 and mediates syncytia formation through interacting with membrane expressed HIV-1 gp120. Further possible roles of the CD4 molecule in the process of cell infection by HIV-1 remain poorly understood. In our study we describe two mAb that recognize the V3/V4 domain of the CD4 molecule. Although these mAb do not inhibit gp120-CD4 binding or HIV-1-induced syncytia formation, they inhibit HIV-1 infection of human PBL. These findings suggest that discrete, definable domains of the CD4 molecule may be involved in interactions after HIV-1 envelope binding that lead to virus entry into the cell.

Antibodies, Monoclonal↗
PubMed1991

Soluble human CD4 elicits an antibody response in rhesus monkeys that inhibits simian immunodeficiency virus replication.

Rhesus monkeys infected with the simian immunodeficiency virus of macaques (SIVmac) demonstrate significant virologic and clinical improvement as a result of treatment with human recombinant soluble CD4 (rsCD4). We show that human rsCD4 does not efficiently inhibit SIVmac replication in bone marrow macrophages of rhesus monkeys and does not significantly augment bone marrow hematopoietic colony formation in vitro. However, plasma of human rsCD4-treated rhesus monkeys does exhibit significant anti-SIVmac activity in vitro. Plasma of these animals efficiently blocks SIVmac replication in peripheral blood lymphocytes and bone marrow macrophages. It also increases granulocyte/macrophage colony formation in vitro by bone marrow cells of SIVmac-infected monkeys. This plasma and the IgG fraction of plasma from a rhesus monkey immunized with human rsCD4 in adjuvant demonstrate reactivity with a soluble form of the rhesus monkey CD4 molecule, exhibit binding to CD4+ but not CD8+ concanavalin A-activated rhesus monkey peripheral blood lymphocytes, and precipitate the CD4 molecule from surface-labeled activated rhesus monkey peripheral blood lymphocytes. Moreover, anti-viral activity is demonstrable in the IgG fraction of plasma from a human rsCD4-immunized monkey. These studies raise the possibility that a modified human CD4 molecule serving as an immunogen might elicit an antibody response that could potentially induce a beneficial therapeutic response in human immunodeficiency virus-infected individuals.

Animals↗
PubMed1991

[Clinical significance of creatine kinase isoform assay by a new reagent based on immunoinhibition method].

Clinical significance of creatine kinase (CK) isoform assay by a new diagnostic reagent based on immunoinhibition method was evaluated. In the method, a monoclonal antibody (CKM-G 01), which inhibits MM3 but not MM1 isoform, was used. Serial serum samples from 143 acute myocardial infarction (AMI) patients were examined in hospitals. Isoform ratio (I.R.: defined as follows; inhibited CK activity/uninhibited CK activity) increased most rapidly (whose peak appeared 8.5 h after onset of AMI), compared with total CK (18.3 h) and CK-MB (16.1 h). In 61 patient samples collected within 4 h from onset, I.R. in 25 samples (41%) exceeded reference interval, whereas total CK in only 17 samples (28%) did it. Reference interval of the I.R. was 0.42 +/- 0.33 (mean +/- SD) in 1,246 normal subjects. These results show that the assay of CK isoforms by the reagents based on immunoinhibition method is useful for earlier detection of AMI.

Antibodies, Monoclonal↗
PubMed1990

Studies of cloned simian immunodeficiency virus-specific T lymphocytes. gag-specific cytotoxic T lymphocytes exhibit a restricted epitope specificity.

CD8+ CTL inhibit the replication of HIV and simian immunodeficiency virus of macaques (SIVmac) in PBL and, therefore, are likely to play an important role in containing the spread of the AIDS virus in infected individuals. We have generated a series of gag-specific lytic T lymphocyte clones from PBL: of an SIVmac-infected rhesus monkey. These T cell clones are CD3+CD8+ and are MHC class I-restricted in their target specificity. They are, therefore, CTL. Interestingly, all gag-specific CTL clones, as well as the gag-specific lytic activity of PBL of this monkey, demonstrated specificity for a single 25 amino acid fragment of the SIVmac gag protein. Moreover, they were restricted in their lytic function by a single MHC class I allele. These findings illustrate a powerful method for cloning AIDS virus-specific T lymphocytes and demonstrate a remarkably restricted epitope specificity of this AIDS virus-specific CTL response.

Animals↗