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M Tanigawa

Publications and source records attributed to M Tanigawa.

At least 37 records · Page 2Linked to original sources
PubMed1999

Allelic diversity at class II DRB1 and DQB loci of the pig MHC (SLA).

The loci encoding the beta chain of the pig major histocompatibility complex (MHC) class II antigens, SLA-DR and -DQ, have been known to exhibit a remarkable degree of allelic polymorphism. Here, to understand the generation of SLA class II polymorphism, 25 SLA-DRB1 and 24 SLA-DQB genes including newly identified 12 SLA-DRB1 and 7 SLA-DQB genes obtained from miniature pigs were analyzed based on the nucleotide and deduced amino acid sequences. Most of the allelic diversity was attributed to the variable sequences which encode a beta1 domain consisting of a beta-pleated sheet followed by an a helix. In the beta1 domain coding region, there were four GC-rich sequences, which have been considered to involve the intra-exon sequence exchange also in other gene evolutions. The first and second GC-rich sequences were alpha-like sequences, which have been shown to be a putative recombination signal, and were stably conserved among SLA-DRB1 and DQB genes. These alpha-like sequences identified in SLA-DRB1 and SLA-DQB were found to encode the first turning point of the beta-pleated sheet and the boundary between the beta-pleated sheet and the alpha helix. Analysis of clustered sequence variation also suggested intra-exon gene conversions in which the alpha-like sequences act as putative breakpoints. In addition to point mutations and selection mechanism, intra-exon gene conversions must be an important mechanism in the generation of allelic polymorphism at the SLA-DRB1 and SLA-DQB.

Alleles↗
PubMed1999

The effects of several nucleotides on the molecular state and catalytic activity of Thiobacillus novellus cytochrome c oxidase. ATP affects the oxidase uniquely.

The catalytic activity and molecular aspects of Thiobacillus novellus cytpchrome c oxidase were affected by ATP. The steady-state kinetics in the oxidation of ferrocytochrome c by the oxidase varied with the presence or absence of ATP; the [S]-v curve of the reaction was sigmoid in the absence of ATP whereas it was a Michaelis-Menten-type hyperbola in the presence of 700 microM ATP. The oxidase was a dimer of the minimal structural subunit consisting of one molecule each of two subunits in the presence of Tween 20 and in the absence of ATP. The dimer dissociated into monomers in the presence of 700 microM ATP. The trough at 452 nm seen in the second derivative absorption spectrum of the CO compound of the oxidase in the absence of ATP, a characteristic of the cytochrome a component of cytochrome aa3, dissappeared in the presence of 700 microM ATP. However, ADP, AMP, GTP, CTP and UTP had little affect on both the [S]-v curve and the molecular mass of the oxidase when used in place of ATP.

Adenosine Triphosphate↗
PubMed1999

Diurnal variations and effects of fasting on blood constituents in minipigs.

We examined the diurnal variations and the effects of 48-hour fasting on hematological and serum biochemical values to obtain basic physiological data on ten male and seven female Göttingen minipigs 6 to 16 months of age. For all hematological parameters examined (RBC, HCT, HGB, WBC and PLT), there was no diurnal variation in either sex, but red blood cell parameters were affected by fasting, with an increase in males and a decrease in females. Three serum biochemical parameters (GOT, UN and i.p.) for males and four (GOT, UN, Ca and i.p.) for females exhibited diurnal variation. These variations were eliminated by fasting. The BIL level in males was increased by fasting, and the color of serum was yellowish. Fe concentration in both sexes and CRE and Mg levels in males were decreased by fasting. These findings are basic data for various experiments on minipigs, and indicate that great care is required in establishing feeding times and fasting intervals and in the analysis of results of experiments on minipigs.

Animals↗
PubMed1999

Power spectral analysis of heart rate variability for assessment of diurnal variation of autonomic nervous activity in miniature swine.

BACKGROUND AND PURPOSES: The purpose of the study was to document diurnal variation of autonomic nervous functions by use of power spectral analysis of heart rate (HR) variability. METHODS: To clarify characteristics of power spectral analysis of HR variability, electrocardiogram (ECG), blood pressure (BP), and respiratory (Resp) waveform simultaneously were recorded. RESULTS: Two major spectral components were examined at low (LF)- and high (HF)-frequency bands for HR variability. Coherence between HR and Resp variabilities and HR and BP variabilities was maximal at approximately 0.14 and 0.03 Hz, respectively. On the basis of these data, two frequency bands of interest--LF (0.01 to 0.07 Hz) and HF (0.07 to 1.0 Hz)--were defined. Autonomic blockade studies indicated that the parasympathetic system mediated the HF and LF components, whereas the sympathetic system mediated only the LF component; HR had a diurnal pattern. The LF and HF bands in the dark phase tended to be higher than those in the light phase. The LF-to-HF ratio had a diurnal pattern similar to that of the HR. CONCLUSION: Parasympathetic nervous activity in miniature swine may be predominant in the dark phase. The characteristics of power spectra and diurnal variations of autonomic nervous functions are almost the same as those of humans. Therefore, miniature swine may be a useful animal model for future biobehavioral and pharmacotoxicologic studies.

Animals↗
PubMed1999

Protection against murine cytomegalovirus retinitis by adoptive transfer of virus-specific CD8+ T cells.

PURPOSE: Human cytomegalovirus retinitis, the most common ophthalmic infection of AIDS patients, has been modeled in BALB/c mice infected with murine cytomegalovirus by the supraciliary route. A series of depletion and adoptive transfer studies was performed to determine whether adoptive transfer of T cells protects mice from retinitis caused by murine cytomegalovirus infection after supraciliary inoculation and to determine which subset of T cells is responsible for protection. METHODS: BALB/c mice were thymectomized and T cell-depleted by injection of monoclonal antibodies to CD4, CD8, or both. Murine cytomegalovirus (9 x 10(2) plaque forming units [pfu]) was injected into the supraciliary space. Experimental animals received murine cytomegalovirus-specific T cells or subsets of T cells 2 hours before virus injection, whereas control animals received herpes simplex virus type 1-specific T cells by tail vein injection. Eight days after virus injection, retinal pathology was scored by histopathologic examination of hematoxylin and eosin-stained ocular sections. RESULTS: CD8+ T cell depletion was sufficient for development of retinitis after supraciliary injection of murine cytomegalovirus. Adoptive transfer of murine cytomegalovirus-specific T cells, but not herpes simplex virus type 1-specific T cells, provided protection from retinitis. Additionally, separation of the murine cytomegalovirus-specific T cells into CD8+ and CD4+ subsets before adoptive transfer showed that the CD8+ fraction of the adoptive T cells was responsible for protection. CONCLUSIONS: These results suggest that adoptive transfer of cytomegalovirus-specific T cells or T cell subsets might be used to treat or prevent cytomegalovirus retinitis in immunosuppressed human patients.

Animals↗
PubMed1998

Motion assimilation for expansion/contraction and rotation and its spatial properties.

In a two-frame apparent motion display, a test grating was displaced horizontally or vertically in the presence of an inducer of which component gratings made up expanding/contracting or rotational motion as a whole. In the first experiment, we demonstrated that motion assimilation did occur for the test accompanied by the two-dimensional motion of the inducer. In the second experiment, we showed that the spatial limit of motion assimilation for expansion/contraction or rotation was large, extending over at least a visual angle of 14-21 deg in diameter, but spatial summation did not occur within the limit. The results were discussed in terms of the interaction between local motion detectors and higher-order detectors which monitor global motion of the whole stimulus pattern.

Humans↗
PubMed1998

Computed tomographic findings in non-specific interstitial pneumonia/fibrosis.

The entity of non-specific interstitial pneumonia/fibrosis (NIP) has recently been recognized as an addition to the current classification of idiopathic interstitial pneumonia, which includes usual interstitial pneumonia, desquamative interstitial pneumonia, diffuse alveolar damage, and bronchiolitis obliterans organizing pneumonia. We studied the computed tomographic (CT) findings of nine NIP patients who were diagnosed pathologically. The main findings were ground glass opacities (66.7%), airspace consolidation (88.9%) and reticular opacities (89.7%), distributed predominantly in the bilateral and lower lung. In all cases, the clinical and abnormal opacification observed on the chest CT was improved by the administration of corticosteroid. Both the subpleural and patchy distributed opacifications predominantly in the bilateral and lower lung, and the good response to treatment may help to differentiate non-specific interstitial pneumonia from other types of idiopathic interstitial pneumonia.

Adult↗
PubMed1998

Orbital tumor in acute myeloid leukemia associated with karyotype 46,XX,t(8;21)(q22;q22): a case report.

Orbital tumor formation in acute myeloid leukemia (AML) is rare as an initial symptom. Furthermore, orbital granulocytic sarcoma (myeloid sarcoma) in pediatric patients is uncommon. We describe a 5-year-old Japanese girl with a left orbital mass as an initial symptom of AML, the mass revealed by computed tomography. Peripheral blood and bone marrow pictures and a chromosomal analysis disclosing 46,XX,t(8;21)(q22;q22) showed AML (M2 according to the French-American-British classification). She was treated with antileukemic chemotherapy systemically. Three weeks after the initiation of chemotherapy, the orbital tumor regressed markedly. AML as an initial symptom of the orbital mass should be fully considered in a differential diagnosis, even in the absence of typical leukemic symptoms, and chromosomal analysis and immunophenotypical analysis may explain the pathogenesis of the extramedullary leukemic tumor.

Acute Disease↗
PubMed1998

Establishment of a 24-hour electrocardiogram recording system using a Holter recorder for miniature swine.

A Holter recording system was established for the Göttingen miniature swine. For this purpose, we first developed a jacket to hold a Holter recording set, and subsequently determined a bipolar lead suitable for obtaining stable electrocardiogram (ECG) recording without artifacts. To make the jacket, we measured the lengths of eight sites of the body of 14 miniature swine. Several types of jackets were made and tested. We observed the behaviour of animals with these jackets by videotape recorder (VTR) recording. These observations permitted development of a jacket suitable for Holter recording. The jacket permits easy placement of the recorder, and long-term ECG recording can be performed without difficulty. In order to determine a suitable lead for long-term recording, we recorded ECGs from six adult miniature swine using three types of leads, the M-X, R-L and A-B leads. The R-L lead frequently exhibited baseline drift, and QRS complexes often disappeared in this lead due to low amplitude. ECG recording with the M-X and A-B leads was of sufficient quality to permit analysis. This system is expected to be useful for further cardiovascular research in miniature swine.

Anesthesia↗
PubMed1998

Complete amino acid sequence of chitinase-A from leaves of pokeweed (Phytolacca americana).

The complete amino acid sequence of pokeweed leaf chitinase-A was determined. First all 11 tryptic peptides from the reduced and S-carboxymethylated form of the enzyme were sequenced. Then the same form of the enzyme was cleaved with cyanogen bromide, giving three fragments. The fragments were digested with chymotrypsin or Staphylococcus aureus V8 protease. Last, the 11 tryptic peptides were put in order. Of seven cysteine residues, six were linked by disulfide bonds (between Cys25 and Cys74, Cys89 and Cys98, and Cys195 and Cys208); Cys176 was free. The enzyme consisted of 208 amino acid residues and had a molecular weight of 22,391. It consisted of only one polypeptide chain without a chitin-binding domain. The length of the chain was almost the same as that of the catalytic domains of class IL chitinases. These findings suggested that this enzyme is a new kind of class IIL chitinase, although its sequence resembles that of catalytic domains of class IL chitinases more than that of the class IIL chitinases reported so far. Discussion on the involvement of specific tryptophan residue in the active site of PLC-A is also given based on the sequence similarity with rye seed chitinase-c.

Amino Acid Sequence↗
PubMed1998

Cloning and characterization of a new swine MHC (SLA) class II DQB allele.

Major histocompatibility complex (MHC) of pigs is known as swine leukocyte antigen (SLA). The cDNA encoding a new allele of SLA class II DQ beta-chain was successfully isolated from a CSK miniature pig (derived from Göttingen strain) and characterized by sequence analyses. SLA-DQB cDNA fragment encoding beta 2-domain was amplified by reverse transcriptase-polymerase chain reaction using the sequences preserved in a various vertebrates as primers. Using non-radioisotope technique with the PCR product as a probe, cDNA clone G01 was isolated from a spleen cDNA library, and nucleotide sequence of this clone was determined. This clone encompassed a whole SLA-DQ beta-chain coding region, containing a total length of 1161 nucleotides with an open reading frame (ORF) of 786 nucleotides, 5' untranslated region of 15 nucleotides, and 3' untranslated region of 360 nucleotides ending with a canonical polyadenylation signal, followed by a poly A tail. Sequence comparisons of the ORF of this clone with those of known SLA-DQB genes confirmed that this clone is a new allele (SLA-DQB*G01). Phylogenetic analysis of the nucleotide sequences of swine, human, and murine MHC class II genes indicated that SLA-DQB was more similar to HLA-DQB1 than H-2A beta. Comparison of the nucleotide and deduced amino acid sequences among SLA-DQB alleles showed that the SLA-DQ beta-chain polymorphism was found almost in beta 1-domain which contains the antigenic peptide binding sites.

Alleles↗
PubMed1998

Differential interleukin 12 responsiveness for interferon gamma production in advanced stages of cancer patients correlates with performance status.

Interleukin 12 (IL-12) has been shown to exhibit potent antitumor activity in murine tumor models through various mechanisms including the capacity to stimulate IFN-gamma production by T cells and natural killer cells. The aim of the present study was to examine the efficacy of IL-12 in inducing IFN-gamma secretion in cancer patients. A comparison was made between healthy individuals who served as controls and cancer patients for IFN-gamma production induced after the stimulation of whole blood samples with 1000 pg/ml IL-12. Samples from all healthy individuals showed positive IL-12 responsiveness. Approximately half of the samples from patients displayed levels of IFN-gamma production comparable to those observed for controls, whereas the rest of the samples exhibited almost-null responses. The incidences for reduced capacity of IFN-gamma production and null IL-12 responsiveness in cancer patients at all cancer stages or at a given advanced stage (stage IV) increased along with performance status. However, these correlated with neither the number of lymphocytes contained in the blood samples nor the tumor types. When peripheral blood mononuclear cells were isolated from patient blood samples showing null/marginal responses, and their responsiveness was examined, 7 of 13 samples exhibited positive responses. Whereas enhanced tumor necrosis factor alpha production was also observed in some patients after IL-12 stimulation, the elevation of tumor necrosis factor alpha was induced only in blood samples that showed IL-12-stimulated IFN-gamma production. These observations indicate that a remarkable difference exists in IL-12 reactivity among cancer patients, and that differential IL-12 responsiveness depends largely on performance status.

Adult↗
PubMed1997

Increased tissue factor pathway inhibitor in patients with acute myocardial infarction.

We examined hemostatic abnormalities in 23 patients with acute myocardial infarction (AMI), 10 with pulmonary embolism (PE), and 10 with deep vein thrombosis (DVT). At the onset of AMI, plasma levels of tissue-type plasminogen activator (t-PA), PA inhibitor-I (PAI-I), fibrin-D-dimer, thrombin-antithrombin complex (TAT), and plasmin-plasmin inhibitor complex (PPIC) were significantly increased. Both the plasma total TFPI and free-TFPI levels in the AMI patients were significantly higher than those in the healthy volunteers, PE patients, and DVT patients. There was no significant difference in total TFPI or free-TFPI among patients with PE, those with DVT, and healthy volunteers. One hour after percutaneous transluminal coronary angioplasty (PTCA) in the AMI group, the total TFPI level was further increased, and it was significantly reduced 24 hr after PTCA, to a level similar to that in healthy volunteers. Free-TFPI showed a pattern similar to that of total TFPI. The ratio of free-TFPI/total TFPI was highest 1 hr after PTCA. Increased TFPI in AMI patients might be released from ischemic tissues.

Adult↗
PubMed1997

In vivo effect of recombinant human leukemia inhibitory factor in primates.

Leukemia inhibitory factor (LIF) is known to be a causative factor for cachexia and thrombocytosis in nude mice bearing human cancer cells. In the present study, we investigated whether recombinant human (rh) LIF can induce these biological activities in a primate model. rhLIF was synthesized by the expression of LIF protein in Escherichia coli. rhLIF (5, 20, or 80 micrograms/kg) was administered subcutaneously twice daily to cynomolgus monkeys for 14 consecutive days. A remarkable decrease of body weight (10%) was observed in the 80 micrograms/kg/day group. Approximately two-fold increases in platelet counts were observed at doses higher than 5 micrograms/kg/day when compared with control counts. These biological effects disappeared soon after the cessation of rhLIF treatment. Macroscopically, a remarkable reduction in subcutaneous fatty tissues and severe splenomegaly were observed. The results of this study demonstrate that rhLIF induces weight loss and thrombocytosis in a primate model.

Alanine Transaminase↗
PubMed1997

Pure amnesia caused by bilateral temporal lobe astrocytoma--case report.

A 32-year-old male presented with progressive pure amnesia caused by astrocytoma invading the bilateral medial temporal lobes. Methionine positron emission tomography demonstrated the extent of tumor invasion well. His memory impairment was partially improved by treatment for the astrocytoma. Lesion of the bilateral hippocampus causes memory impairment, but pure memory loss without other associated neurological sign or deterioration of consciousness is rare in a case of cerebral neoplasm.

Adult↗
PubMed1996

Continuous monitoring of cellular nitric oxide generation by spin trapping with an iron-dithiocarbamate complex.

Nitric oxide (NO) generation in murine macrophages was determined in real time using the electron paramagnetic resonance (EPR) spin trapping method. An iron complex of N-methyl D-glucamine dithiocarbamate was utilized as the spin trap. This spin trapping compound reacts with NO in solution to form a specific room-temperature stable, mononitrosyl complex which is readily detected and identified by EPR spectroscopy. Mouse peritoneal macrophages were placed in an EPR sample-cell and activated by lipopolysaccharide and gamma-interferon at 37 degrees C, followed by an additional incubation in oxygenated medium without these activation agents. After various incubation periods, spin trap solution was infused to replace the medium in the sample-cell, and the time-evolution of the EPR signal of the spin adduct (NO-complex) was recorded. Rates of NO generation were calculated based upon the initial slopes of the increase in the EPR intensity with time. In comparison to the NO (or NO2-) generation rate obtained under similar experimental conditions using the Griess reaction assay, the spin trapping method was found to be more sensitive, with a lowest limit of the detection of 3 pmol/min. In addition, by using the spin trapping method, NO generation from the same cells could be measured consecutively during various stages of activation, because infusion of the spin trap solution did not affect the viability of macrophages.

Animals↗