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T Saito

Publications and source records attributed to T Saito.

At least 109 records · Page 6Linked to original sources

Isolation of peptides useful for differential diagnosis of Crohn's disease and ulcerative colitis.

BACKGROUND: Phage displayed random peptide technology has been utilised to identify binding epitopes of antibodies or receptor ligands. AIM: To isolates peptides from a phage library which are specifically recognised by antibodies in serum from patients with Crohn's disease (CD). METHODS: A phage displayed random peptide library composed of nine amino acids was established and sequentially screened using serum immunogloblin G obtained from CD patients. RESULTS: Five different CD specific peptides were isolated from the phage library. No homology in amino acid sequences was observed among four (CDP-1, -3 to -5) of the five peptides exhibiting different binding characteristics with each CD patient's serum. In contrast, two peptides (CDP-1 and -2) had similar amino acid sequences and similar binding characteristics. Four multiple antigenic peptides (MAP, CDP-1, -3 to -5) were synthesised, and an enzyme linked immunosorbent assay (ELISA) using the four peptides was developed to detect serum antibodies against them. Fifty two of 92 CD patients (56.5%) were detected by ELISA, none of 20 ulcerative colitis (UC) patients, only one of 25 duodenal ulcer patients, and only three of 48 healthy subjects. CONCLUSIONS: ELISA using the four peptides isolated in this study may be useful for the differential diagnosis of CD and UC.

Amino Acid Sequence↗

Mucosal sulfhydryl compounds evaluation by in vivo electron spin resonance spectroscopy in mice with experimental colitis.

BACKGROUND: Sulfhydryl (SH) compounds are essential in maintaining mucosal integrity in the gastrointestinal tract. A decrease in colonic mucosal SH compounds affects the redox status of the mucosa, resulting in vulnerability to further attacks. Therefore, there is a strong need for in vivo evaluation of SH compounds in the colonic mucosa. AIMS: The aim of the current study was to establish a method of evaluating levels of SH compounds in the colonic mucosa of live animals before and after induction of colitis. METHODS: Murine experimental colitis was induced by instillation of trinitrobenzene sulphonic acid (TNBS) dissolved in 50% ethanol into the colon via the anus. For evaluation of mucosal SH compounds in the colon, 3-carbamoyl-2,2,5,5-tetramethylpyrrolidine-1-oxyl (carbamoyl-PROXYL), a stable nitroxide radical, was instilled into the colonic lumen of live mice and the spin clearance rate was measured by L-band electron spin resonance (ESR) spectroscopy. RESULTS: Morphological study showed that mucosal damage was severe one or two days after TNBS instillation. The colonic mucosa started to regenerate at four days, and looked normal at seven days, after induction of colitis. The spin clearance rate of carbamoyl-PROXYL decreased significantly at 0.5, 1, 2, and 4 days after induction of colitis compared with mice before TNBS instillation. Surprisingly, although the colonic mucosa looked normal seven days after TNBS administration, the spin clearance rate still remained significantly slow. The spin clearance rate returned to normal 14 days after induction of colitis. The change in in vivo spin clearance rate was consistent with the time dependent change in mucosal reduced glutathione, a major component of SH compounds. CONCLUSION: The spin clearance rate obtained by L-band ESR spectroscopy in combination with carbamoyl-PROXYL can give an estimate of the level of colonic mucosal SH compounds in live animals and is useful for evaluating the mucosal defence system against oxidative stress.

Animals↗

Incidence and predicting factors of hypozincemia in very-low-birth-weight infants at near-term postmenstrual age.

We prospectively investigated serum zinc (Zn) concentrations and clinical factors in 118 very-low-birth-weight infants with a gestational age of 29.5 +/- (SD) 2.5 weeks and a birth weight of 1,194 +/- 254 g at near-term postmenstrual age. The 25th percentile of the serum Zn concentration was 7.0 micromol/l. The infants whose serum Zn concentrations were less than 7.0 micromol/l (defined as hypozincemia) did not have apparent symptoms of Zn deficiency. Multivariate logistic regression analyses demonstrated that hypozincemia was associated with factors such as weight gain (1-g/kg/day increase of weight; OR 1.1762, 95% CI 1.0414-1.3286) and serum albumin concentration (1-g/dl increase of serum albumin; OR 0.0816, 95% CI 0.0152-0.4372). The types of milk feeding did not affect the serum Zn concentrations in the study subjects. This study suggests that hypozincemia in very-low-birth-weight infants at near-term postmenstrual age is associated with greater weight gain and lower serum albumin concentration. Nutritional supply of Zn by human milk fortifier and preterm formula does not appear to meet the demands of rapidly growing very-low-birth-weight infants.

Gestational Age↗

Paraoxonase (Pon1) Q192R polymorphism and serum Pon1 activity in diabetic patients on maintenance hemodialysis.

Patients with diabetic nephropathy have an increased risk of coronary heart disease (CHD). Paraoxonase (Pon1) is a high-density lipoprotein- (HDL) associated enzyme that protects low-density lipoprotein from oxidation and also protects against atherosclerosis. We investigated the relationship of serum Pon1 activity, Pon1 Q192R polymorphism and HDL-C level to type 2 diabetes mellitus (DM) in patients on maintenance hemodialysis (HD). DM patients (n = 56, F/M = 17/39, aged 64.5 +/- 7.5 years) and non-DM patients (n = 89, F/M = 28/61, aged 62.7 +/- 8.3 years) under HD were included in this study. Salt-stimulated serum Pon1 activities were measured using paraoxon as a substrate. Pon1 Q192R polymorphism was detected by the mutagenically separated polymerase chain reaction. DM patients on HD had significantly lower HDL-C levels and serum Pon1 activities than non-DM patients on HD (657 +/- 277 vs. 763 +/- 257 IU/l, p < 0.01). The distribution of Pon1 Q 192R genotypes in all subjects did not differ from that predicted from the Hardy-Weinberg equilibrium. Serum Pon1 activities in both DM and non-DM patients on HD were regulated by Pon1 Q192R polymorphism: RR > QR > QQ. However, the reduced Pon1 activities in DM patients on HD were related to DM independent of the Pon1 genotype: reduced Pon1 activity was related to DM in RR carriers. Serum Pon1 activities were positively correlated with HDL-C levels. The association between HDL-C and DM in hemodialyzed patients was independent of Pon1 activity as assessed by an analysis of variance. But the relation between Pon1 activity and DM was modified by HDL-C levels: significantly when HDL-C was below 50 mg/dl, but not significantly when HDL-C was above 50 mg/dl. The results of a logistic regression analysis show that reduced serum Pon1 activities and low HDL-C levels were additively associated with DM. In conclusion, Pon1 status and HDL levels are independently associated with DM in patients on hemodialysis and may contribute to the increased risk of CHD in diabetic nephropathy.

Aged↗

[Utility of the perfusion-assist for beating heart coronary artery bypass surgery].

During off-pump coronary artery bypass surgery, concern remains about the possible myocardial injury associated with the transient occlusion and stabilization of the target vessels. To try to minimize myocardial ischemia and achieve hemodynamic stability, we utilized a coronary perfusion catheter combined with the perfusion-assisted direct coronary artery bypass system that enables active and modified coronary perfusion of the target vessel throughout the duration of multiple grafting (modified PADCAB). In the series of 10 patients, perfusion of the target coronary systems averaged 2,072.8 +/- 649.7 ml over 92.9 +/- 26.1 minutes under a constant infusion pressure of 120 mmHg. Nitroglycerin (100 micrograms/l of flow) was delivered directly into the coronary arteries as an additive in all patients. Hemodynamic instability was notably absent in all cases, even in cases that required difficult anastomosis with a relatively long time for the anastomosis. There were no perioperative complications and no detectable myocardial damage (i.e., impairment of myocardial wall motion indicated by echocardiography findings or by > 0.25 ng/ml of troponin-T release compared to the preoperative level) in this series of patients.

Aged↗

Immunohistochemical study of macrophage migration inhibitory factor in rat liver fibrosis induced by thioacetamide.

Macrophage migration inhibitory factor (MIF) is a molecule known to regulate macrophage accumulation at sites of inflammation. To elucidate the role of MIF in progression of liver fibrosis, the immunohistochemical localization of MIF and macrophages in the liver were examined. Male Wistar rats received thioacetamide (TA) injections (200 mg/kg, i.p.) for 1 or 6 weeks. In biochemical and histological tests, it was confirmed that liver fibrosis was induced. In immunohistochemical analyses, the expression of MIF protein was seen in hepatocytes in the areas extending out from the central veins to the portal tracts. In particular, at 6 weeks, immunoreactivity was detected in degenerated hepatocytes adjacent to the fibrotic areas but hardly observed in the fibrotic areas. On the other hand, a number of exudate macrophages stained by antibody ED1 were seen in the areas from the central veins to the portal tracts at 1 week and in the fibrotic areas at 6 weeks. Macrophages also showed a significant increase in number as compared with controls. These results revealed that there was a close relationship between the appearance of MIF expression and ED1-positive exudate macrophages in degenerated hepatocytes during the progression of TA-induced liver fibrosis.

Animals↗

Q2 evolution of the generalized Gerasimov-Drell-Hearn integral for the neutron using a 3He target.

We present data on the inclusive scattering of polarized electrons from a polarized 3He target at energies from 0.862 to 5.06 GeV, obtained at a scattering angle of 15.5 degrees. Our data include measurements from the quasielastic peak, through the nucleon resonance region, and beyond, and were used to determine the virtual photon cross-section difference sigma(1/2)-sigma(3/2). We extract the extended Gerasimov-Drell-Hearn integral for the neutron in the range of four-momentum transfer squared Q2 of 0.1-0.9 GeV2.

Journal Article↗

Sigma-nucleus potential in A=28.

We have studied the (pi(-),K+) reaction on a silicon target to investigate the sigma-nucleus potential. The inclusive spectrum was measured at a beam momentum of 1.2 GeV/c with an energy resolution of 3.3 MeV (FWHM) by employing the superconducting kaon spectrometer system. The spectrum was compared with theoretical calculations within the framework of the distorted-wave impulse approximation, which demonstrates that a strongly repulsive sigma-nucleus potential with a nonzero size of the imaginary part reproduces the observed spectrum.

Journal Article↗

Genetic linkage maps constructed by using an interspecific cross between Japanese and European pears.

Genetic linkage maps of the European pear ( Pyrus communis L.) cultivar 'Bartlett' and the Japanese pear ( Pyrus pyrifolia Nakai) cultivar 'Housui' were constructed based on AFLPs, SSRs from pear, apple and Prunus, isozymes and phenotypic traits by using their F(1) progenies. The map of the female parent Bartlett consisted of 226 loci including 175 AFLPs, 49 SSRs, one isozyme and one S locus on 18 linkage groups over a total length of 949 cM, while that for 'Housui' contained 154 loci including 106 AFLPs, 42 SSRs, two phenotypic traits and the other four markers on 17 linkage groups encompassing a genetic distance of 926 cM. These maps were partially aligned using 20 codominant markers which showed segregating alleles in both parents. Compared with the reports of apple genetic maps, these pear maps were not saturated but were near saturation. Distorted segregation was observed in two and one regions of the genome of Bartlett and Housui, respectively. The position of 14 SSRs originating from apple could be successfully determined in pear maps, which enabled us to compare the two maps. Some SSRs developed from Prunus (peach, cherry) were also mapped. The relationships between pear and the other species belonging to the Rosaceae were discussed based on the position of SSRs.

Chromosome Mapping↗

Green revolution: a mutant gibberellin-synthesis gene in rice.

The chronic food shortage that was feared after the rapid expansion of the world population in the 1960s was averted largely by the development of a high-yielding semi-dwarf variety of rice known as IR8, the so-called rice 'green revolution'. The short stature of IR8 is due to a mutation in the plant's sd1 gene, and here we identify this gene as encoding an oxidase enzyme involved in the biosynthesis of gibberellin, a plant growth hormone. Gibberellin is also implicated in green-revolution varieties of wheat, but the reduced height of those crops is conferred by defects in the hormone's signalling pathway.

Crops, Agricultural↗

Quantitative analysis of NF-kappaB-expression in cartilage and synovium of rat knee induced by intra-articular injection of synthetic lipid A.

OBJECTIVE: NF-kappaB expression in cartilage and synovium of rat knee after intra-articular injection of lipid A was investigated. METHODS: Inflammation was evaluated in histological sections stained with hematoxylin and eosin, toluidine blue and immunostained with monoclonal anti-NF-kappaB antibody or monoclonal anti-TNF-alpha antibody. RESULTS: Inflammatory cell infiltration into the synovium, hyperplasia of synovial lining layers, loss of metachromasia of cartilage, TNF-alpha-positive cells and NF-kappaB-positive cells in the synovium and cartilage were observed in all 26 rat knees intra-articularly injected with lipid A. The numbers of TNF-alpha-positive and NF-kappaB-positive synovial cells and chondrocytes after the injection were significantly greater than those in knees injected with triethylamine (p < 0.05). The amount of inflammatory cell infiltration into the synovium, synovial lining layers, TNF-alpha-positive synovial cells and NF-kappaB-positive synovial cells 12 h after the injection was significantly smaller than those after 1 day (p < 0.05). CONCLUSION: Intra-articular injection of lipid A induced NF-kappaB expression in cartilage and synovium. Cartilage degeneration started earlier than synovitis in this model. Quantitative analysis of NF-kappaB in cartilage might be useful to evaluate the extreme acute phase of cartilage degeneration.

Animals↗

Hemorrhagic infarction of fibroma. MR imaging appearance.

We experienced a case of hemorrhagic infarction of the ovarian fibroma and that indicated the characteristic following appearance: exhibiting a high signal intensity area observed at the periphery of mass on T1-weighted MRI (magnetic resonance imaging). It was thought that this appearance developed because hemorrhagic infarction was caused by subacute ovarian torsion. This is a useful finding for suspecting hemorrhagic infarction preoperatively.

Abdominal Pain↗

Effects of diet consistency on the myosin heavy chain mRNAs of rat masseter muscle during postnatal development.

To study the effects of diet consistency on the fiber phenotypes of rat masseter (1-70 days of age), the mRNAs of myosin heavy chain isoforms (MHC embryonic, neonatal, I, IIa, IId/x and IIb) were measured in total RNA preparations from masseters of hard-diet group (HDG) and soft-diet group (SDG) by competitive reverse transcriptase-polymerase chain reaction (RT-PCR). With respect to the time course of the transition of each MHC mRNA expressed as a percentage relative to the maximum mean, the soft diet facilitated early (9 days after weaning) expression of IId/x and IIb isoforms, and also a decline in the expression of neonatal and IIa isoforms. The expression of neonatal, IIa and IId/x isoforms at 70 days of age was significantly (P<0.05, P<0.01, P<0.01, respectively) lower in SDG than in HDG, indicating a higher relative composition of the IIb isoform in the SDG. Embryonic MHC mRNA had disappeared by 14 days of age (i.e. before weaning at 19 days). No MHC I mRNA was observed in any masseter studied. These results suggest that in the rat a soft diet facilitates an even more MHC IIb-rich phenotype in the masseter muscle than a hard diet.

Animals↗

Postnatal changes in the nicotinic acetylcholine receptor subunits in rat masseter muscle.

No published study on synaptogenesis in masseter muscle has focused on the shift of nicotinic acetylcholine receptors (nAChRs) from the embryonic type (alpha(2)-, beta-, gamma- and delta-subunits) to the adult-type (alpha(2)-, beta-, epsilon- and delta-subunits) and the elimination of nAChRs outside the neuromuscular junction. To identify the time course of the nAChR transitions in rat masseter muscle between 1 and 63 days of age, the expression of delta-, epsilon- and gamma-subunit mRNAs was analysed by competitive polymerase chain reaction in combination with reverse transcription. The expression of the delta-subunit was high between 1 and 7 days of age, then decreased by 95% (P<0.0001) between 7 and 28 days, suggesting that the nAChR elimination occurs during this period. The quantity of the epsilon-subunit increased by approximately 600% (P<0.0001) between 1 and 21 days of age, whereas the quantity of the gamma-subunit decreased by 85% (P<0.0001) during the same period. This result indicates that the nAChR type shift is terminated at 21 days of age. The feeding behaviour of the rats inevitably changed from suckling to biting after 19 days of age, because they were weaned at that age. As the nAChR type shift was terminated soon after weaning, the termination could be related to the change in feeding behaviour. However, it might also be the case that nAChR elimination is not directly related to the change in feeding behaviour, as the elimination continued at the same rate for 9 days after weaning (from 19 to 28 days of age).

Animals↗

FcgammaRI (CD64) contributes substantially to severity of arthritis, hypersensitivity responses, and protection from bacterial infection.

The high-affinity receptor for IgG, FcgammaRI, shares its capacity to bind IgG2a immune complexes (IgG2a-IC) with the low-affinity receptor FcgammaRIII and complement factors, hampering the definition of its biological role. Moreover, in vivo, FcgammaRI is occupied by monomeric IgG2a, reducing its accessibility to newly formed IgG2a-IC. By using a variety of FcgammaR(-/-) mice, we demonstrate that in the absence of FcgammaRI, the IgG2a-IC-induced cellular processes of phagocytosis, cytokine release, cellular cytotoxicity, and antigen presentation are impaired. FcgammaRI(-/-) mice showed impaired hypersensitivity responses, strongly reduced cartilage destruction in an arthritis model, and impaired protection from a bacterial infection. We conclude that FcgammaRI contributes substantially to a variety of IgG2a-IC-dependent immune functions and immunopathological responses.

Animals↗