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H Itoh

Publications and source records attributed to H Itoh.

At least 55 records · Page 3Linked to original sources
PubMed2002

Oligoclonal accumulations of T-cell clones in gingivitis and periodontitis lesions.

Gingivitis and periodontitis have distinct clinical and immunopathological characteristics. We have previously demonstrated that T cells infiltrating periodontitis lesions recognize a restricted repertoire of antigens or antigenic epitopes. However, the clonality of T cells in the gingivitis lesion is not known. Therefore, we carried out a clonal analysis of T cells infiltrating gingivitis lesions using combined reverse transcription-polymerase chain reaction and single-strand conformation polymorphism (SSCP) analysis. As with periodontitis lesions, SSCP analysis demonstrated the emergence of a number of distinct bands suggesting clonal accumulation in the gingivitis lesion. Although the mean number of distinct bands in gingival tissue was significantly higher than that in peripheral blood mononuclear cells, numerical analysis clearly demonstrated that there was no difference in the total number of bands in gingival tissue specimens between the different disease types. Although there were slight variations in the number of distinct bands in each Vbeta family, there was no significant difference between gingivitis lesions and periodontitis lesions. These results demonstrate that antigen-specific T-cell responses also take place in gingivitis lesions. It remains to be determined, however, what role these antigen-specific T cells play and what antigens the T cells recognize in the pathogenesis of periodontal disease.

Clone Cells↗
PubMed2002

Role of leptin in pregnancy--a review.

Leptin is an adipocyte-derived hormone that decreases food intake and body weight via its receptor in the hypothalamus. In rodents, it also modulates glucose metabolism by increasing insulin sensitivity. We previously reported that leptin is produced by human placental trophoblasts. We also revealed that leptin gene expression in the placenta was augmented in severe pre-eclampsia, and suggested that placental hypoxia may play a role in this augmentation. Maternal plasma leptin levels correlated well with mean blood pressure, but not with body mass index. Plasma leptin levels in pre-eclamptic women with IUGR were higher than those without IUGR (P< 0.05). We further examined the effects of hyperleptinemia on the course of pregnancy by using transgenic mice (Tg) overexpressing leptin. In pregnant Tg mice, food intake was significantly less than non-Tg, and the fetal body weights were reduced to approximately 70 per cent of those of non-Tg. Resistin is a novel adipocyte-derived hormone that decreases insulin sensitivity and increases plasma glucose concentration, thus contributing the development of obesity-related type II diabetes mellitus. We recently found that resistin gene is expressed in the human placenta as well as adipose tissue. In this review, possible roles of placental leptin and resistin are discussed.

Adult↗
PubMed2002

Hepatocyte growth factor in human breast milk acts as a trophic factor.

To evaluate the significance of hepatocyte growth factor (HGF) in milk in the perinatal period, we examined immunoreactive HGF levels and bioactivity in human milk. Human milk samples were obtained from women at various postpartum ages, and the levels of HGF were measured by ELISA. In the cross sectional study, the concentration of milk HGF from term deliveries showed a significant inverse correlation with progress of lactation, whereas in cases of preterm delivery concentrations, levels remained high after a long period of lactation. In the longitudinal analysis, the contents of HGF in colostrum, transitional, and mature milk from preterm deliveries were significantly be higher than those from term deliveries. Although mature milk from term and preterm deliveries contained significantly lower levels of HGF than colostrum, high levels of HGF persisted in mature milk from preterm deliveries. After partial purification, immunoblotting analysis showed the presence of both alpha- and beta-chains of HGF. HGF in milk stimulated proliferation of rat hepatocytes in primary culture, which was inhibited by supplementation with anti-HGF antibody. Thus, a high concentration of bioactive HGF is present in human milk in the postpartum period. Our results suggest that HGF in milk acts as a trophic factor for the gastrointestinal tract in neonates.

Adult↗
PubMed2002

Effects of dietary chitosan on fat deposition and lipase activity in digesta in broiler chickens.

1. The effect of dietary chitosan on fat deposition and lipase activity in the small intestinal contents was investigated in broiler chickens fed an adequate or high metabolisable energy (ME) diet. 2. Male broiler chickens at 14 d old were fed on the adequate or high ME diet supplemented with 0 or 50 g/kg chitosan, which has a low viscosity, for 3 weeks. 3. Dietary chitosan did not affect food intake, body weight gain or food efficiency in either dietary ME groups. 4. Dietary chitosan reduced the excessive abdominal fat deposition induced by the high ME diet. 5. Dietary chitosan increased the weight of intestinal contents irrespective of dietary ME concentration. 6. Dietary chitosan decreased the lipase activity per g of small intestinal contents. 7. These results suggest that dietary chitosan with low viscosity decreases lipase activity and fat absorption in the small intestine, consequently resulting in a reduction of fat deposition in broiler chickens. 8. It was concluded that dietary chitosan with low viscosity can decrease body fat deposition without reducing food intake and body weight gain in broiler chickens.

Abdomen↗
PubMed2001

Antisense oligodeoxynucleotide targeted to Midkine, a heparin-binding growth factor, suppresses tumorigenicity of mouse rectal carcinoma cells.

Midkine (MK), a heparin-binding growth factor, is overexpressed in a wide range of human carcinomas and is believed to contribute to tumorigenesis and tumor progression. To develop an antitumor reagent, we designed a phosphorothioate antisense oligodeoxynucleotide molecule based on the secondary structure of MK mRNA. The antisense MK at the dosage of 5 microM suppressed MK production by CMT-93 mouse rectal carcinoma cells after cationic liposome-mediated transfection, to 13% of that in control cultures. The growth of CMT-93 cells and their colony formation in soft agar were inhibited by the addition of the antisense MK, whereas the control reagent, the sense MK, showed no effects. On s.c. injection into nude mice, CMT-93 cells transfected with the antisense MK formed tumors much smaller than those by control cells. Finally, untreated CMT-93 cells were inoculated to nude mice, and 7 days later the antisense MK (50 microM) with atelocollagen was directly injected into the preformed tumor region to evaluate the curative effect; the injection was repeated at the interval of 2 weeks. During the period of 10-41 days after initiation of therapy, the rate of increase of tumor volume treated with the antisense MK was found to be about 4.2-fold lower than that seen after treatment with the sense MK. On this occasion, proliferation of tumor cells as estimated by 5-bromodeoxyuridine incorporation was strongly inhibited, whereas angiogenesis was less affected. These findings strongly suggested the usefulness of MK antisense oligodeoxynucleotide as a new reagent for cancer therapy.

Amino Acid Sequence↗
PubMed2001

Galphaq-dependent activation of mitogen-activated protein kinase kinase 4/c-Jun N-terminal kinase cascade.

G-protein-coupled receptors (GPCRs) typically activate c-Jun N-terminal kinase (JNK) through the G protein betagamma subunit (Gbetagamma), in a manner dependent on Rho family small GTPases, in mammalian cells. Here we show that JNK activation by the prototypic Gq-coupled alpha1B-adrenergic receptor is mediated by the alpha subunit of Gq (Galphaq), not by Gbetagamma, using a transient transfection system in human embryonic kidney cells. JNK activation by the alpha1B-adrenergic receptor/Galphaq was selectively mediated by mitogen-activated protein kinase kinase 4 (MKK4), but not MKK7. Also, MKK4 activation by the alpha1B-adrenergic receptor/Galphaq required c-Src and Rho family small GTPases. Furthermore, activation of the alpha1B-adrenergic receptor stimulated JNK activity through Src family tyrosine kinases and Rho family small GTPases in hamster smooth muscle cells that natively express the alpha1B-adrenergic receptor. Together, these results suggest that the alpha1B-adrenergic receptor/Galphaq may up-regulate JNK activity through a MKK4 pathway dependent on c-Src and Rho family small GTPases in mammalian cells.

Animals↗
PubMed2001

Quantitative evaluation of magnetic resonance imaging of deep white matter hyperintensity in geriatric patients by multifractal analysis.

Fractal analysis has played an important role in various fields such as physics, biology and medicine. Recently, multifractal analysis based on generalized concepts of fractals has been applied to biological tissues composed of complex structures. Deep white matter hyperintensity (DWMH) on brain magnetic resonance imaging (MRI) is more often observed in patients with geriatric depression than in healthy elderly subjects, and its clinical significance is receiving attention. We applied multifractal analysis to white matter images on brain T2-weighted MRI in 62 patients with geriatric depression (50-75 years). The local fractal dimensions, alpha(max) and alpha(min), which serve as indices of complexity, and their difference, alpha(max) - alpha(min), were closely correlated with the macroscopic grading according to Fazekas classification, suggesting that multifractal analysis is useful for quantitative evaluation of DWMH on MRI.

Aged↗
PubMed2001

Risk factors for massive hemoptysis after endobronchial brachytherapy in patients with tracheobronchial malignancies.

BACKGROUND: Massive and mostly fatal hemoptysis is a frequently reported morbidity after endobronchial brachytherapy (EBB) for tracheobronchial malignancies. However, to the authors' knowledge, it remains controversial whether this morbidity is related directly to EBB. To investigate whether massive hemoptysis is related to EBB, the authors retrospectively analyzed risk factors for massive hemoptysis after EBB. METHODS: Thirty-six patients (30 men and 6 women) with a mean age of 70 years underwent high-dose rate EBB for tracheobronchial malignancy using a cobolt-60 (Co-60) afterloading machine. EBB was performed as primary therapy in 6 patients and as salvage treatment for recurrent disease in 30 patients. EBB was delivered to the tracheal lesions in 15 patients and to the main bronchial lesions in 21 patients. EBB was combined with external beam radiation therapy (EBRT) in 24 patients, with laser photocoagulation in 3 patients, and with EBRT plus laser photocoagulation in 5 patients. The dose of EBRT delivered with the EBB ranged from 16-69 grays (Gy), with a mean dose of 37 Gy. RESULTS: At a mean follow-up of 18 months, 33 of the 36 patients had died. Eight of the 33 patients had no evidence of local disease at the time of death. Seven patients died of massive hemoptysis. The cumulative rate of massive hemoptysis was 29.4% at 2 years. According to univariate analysis, no statistically significant correlation with massive hemoptysis was observed for EBRT dose delivered in combination with EBB, EBB fractional and total doses, EBB length, and the sum of all the EBRT doses including that used for the initial treatment. Local failure or persistent malignancy (P = 0.033) and delivery of laser photocoagulation (P = 0.032) were found to be statistically significantly associated with massive hemoptysis. Direct contact between the EBB applicator and the tracheobronchial walls at the vicinity of the great vessels was observed in 16 patients and was found to be statistically significantly associated with massive hemoptysis (P = 0.003). In six patients, the applicator was in direct contact with two or more tracheobronchial walls at the vicinity of the great vessels; all these patients died of massive hemoptysis. CONCLUSIONS: Direct contact between the EBB applicator and the tracheobronchial walls at the vicinity of the great vessels was one of the significant risk factors for massive hemoptysis. To prevent massive hemoptysis, a specific spacer should be employed to maintain a safe distance between the applicator and the bronchial wall.

Aged↗
PubMed2001

Serial MRI and (1)H-MRS of Wernicke's encephalopathy: report of a case with remarkable cerebellar lesions on MRI.

Before and after the administration of thiamine (vitamin B(1)), MRI and proton magnetic resonance spectroscopy ((1)H-MRS) were serially performed in a patient with Wernicke's encephalopathy demonstrating remarkable cerebellar lesions on MRI. Before thiamine administration, high signal intensities were observed in the thalamus around the third ventricle and in the superior portion of the cerebellar vermis and hemisphere on fluid-attenuated inversion recovery (FLAIR) and T2-weighted MR images. After thiamine administration, the high signal intensity in the former region disappeared immediately, while that in the latter regions persisted. The low level of N-acetylaspartate (NAA)/creatine (Cr) in the thalamus before thiamine administration improved to some degree on the (1)[H]-MRS images taken after thiamine administration. In the cerebellum, a lactate peak was observed before thiamine administration, and the NAA/Cr level did not improve after thiamine administration, suggesting that irreversible necrosis occurred. It is suggested that serial MRI/(1)H-MRS observation may be helpful in determining the neuronal viability of Wernicke's encephalopathy and the prognostic implications of sequelae such as Korsakoff's syndrome and cerebellar ataxia.

Aged↗
PubMed2001

Identification of hepatocyte growth factor activator inhibitor type 2 (HAI-2)-related small peptide (H2RSP): its nuclear localization and generation of chimeric mRNA transcribed from both HAI-2 and H2RSP genes.

A novel small gene, designated hepatocyte growth factor activator inhibitor type 2 (HAI-2)-related small peptide (H2RSP) was cloned and characterized in the process of the search for splicing variant forms of HAI-2 by 3'-rapid amplification of cDNA ends (RACE). The gene consisted of 4 exons spanning approximately 1 kb and was located in 11 kb downstream of HAI-2 gene (19q.13.11). The novel transcript identified by 3'-RACE was thought to be chimerically transcribed from both HAI-2 (exons 1-7) and H2RSP (exons 2-4) genes. Wild-type H2RSP mRNA (0.5 kb) was detected abundantly in various tissues including the gastrointestinal tract, whereas chimeric mRNA (1.5 kb) was found mainly in the kidney, prostate, and placenta by Northern blot analysis. The predicted amino acid sequence of H2RSP contained two unique domains, namely the serine-rich region (exon 3) and the lysine-rich region (exon 4). Transfection of deleted series of H2RSP cDNAs fused to enhanced green fluorescent protein (EGFP) into HeLa cells revealed that H2RSP has nuclear localization signal in the lysine-rich region. Immunohistochemical study using anti-H2RSP polyclonal antibody indeed revealed the nuclear localization of this peptide in vivo. These results suggest that H2RSP and H2RSP/HAI-2 chimeric peptides might function as a transcriptional regulatory peptide at the nucleus.

Amino Acid Sequence↗
PubMed2001

Galpha11 induces caspase-mediated proteolytic activation of Rho-associated kinase, ROCK-I, in HeLa cells.

Expression of the constitutively active mutant of Galpha(11) (Galpha(11)QL) induces the formation of vinculin-containing focal adhesion-like structures in HeLa cells. This was found to be inhibited by Y-27632, a specific inhibitor of Rho-associated kinases (ROCK), but not by co-expression with a dominant negative mutant of RhoA, suggesting Rho-independent activation of ROCK by Galpha(11)QL. Investigation of trypan blue exclusion and immunocytochemistry with an antibody against cleaved caspase revealed the cellular phenotype of Galpha(11)QL-expressing cells to be identical to that displayed by cells undergoing apoptosis, and the caspase inhibitor zVAD-fmk blocked all morphological changes induced by Galpha(11)QL. Transfection of Galpha(11)QL induced cleavage of ROCK-I, and this proteolysis was also prevented by zVAD-fmk. ROCK-I C-terminally truncated at its authentic caspase sites also induced the formation of vinculin-containing focal adhesion-like structures. In addition, cleavage of ROCK-I was observed when cells overexpressing m1 muscarinic acetylcholine receptors were stimulated with carbachol. These results suggest that Galpha(11) induces proteolytic activation of ROCK-I by caspase and thereby regulates the actin cytoskeleton during apoptosis.

Calcium↗
PubMed2001

Reduced expression of hepatocyte growth factor activator inhibitor type-2/placental bikunin (HAI-2/PB) in human glioblastomas: implication for anti-invasive role of HAI-2/PB in glioblastoma cells.

Hepatocyte growth factor activator inhibitor type-2/placental bikunin (HAI-2/PB) is a serine proteinase inhibitor that contains 2 Kunitz-domains and a presumed transmembrane domain. It has broad inhibitory spectra against various serine proteinases showing potent inhibitory activities not only to hepatocyte growth factor activator but also to plasmin, trypsin and kallikreins. In this study, we investigated the expression of HAI-2/PB in human gliomas in vivo and the effects of HAI-2/PB on the fibrinolytic and invasive capabilities of human glioblastoma cells in vitro. With RNA blot analysis, HAI-2/PB mRNA was expressed in normal brain and in low-grade astrocytomas, but was hardly detectable in anaplastic astrocytomas and glioblastomas, indicating that its expression levels were inversely correlated with the histological grade of human gliomas. To further explore the possible role of HAI-2/PB in glioma progression, cultured human glioblastoma cell lines (U251 and YKG-1) were transiently transfected with an expression vector harboring human HAI-2/PB cDNA. Subsequent analysis indicated that the expression of HAI-2/PB suppressed the fibrinolytic activities of both glioblastoma cell lines. Moreover, HAI-2/PB inhibited Matrigel invasion of U251 and YKG-1 cells by 30% and 64%, respectively. This anti-invasive effect appeared to be mediated primarily by the inhibitory activity of HAI-2/PB against the serine proteinase-dependent matrix degradation. These findings suggest that the reduced expression of HAI-2/PB is possibly involved in the progression of human gliomas.

Astrocytoma↗
PubMed2001

Early-phase enhanced inflammatory reaction after spinal instrumentation surgery.

STUDY DESIGN: The erythrocyte sedimentation rate, C-reactive protein, white blood cell count, and body temperature were measured prospectively in patients after two types of spinal surgery without complications and three cases of infection after spinal instrumentation surgery. OBJECTIVES: To investigate the effects of instrumentation on postoperative inflammatory reaction, and to describe early detection of postoperative wound infection. SUMMARY OF BACKGROUND DATA: In thoracic and abdominal surgery as well as hip arthroplasty, C-reactive protein has proved more valuable than erythrocyte sedimentation rate for early detection of postoperative infectious complications. It has not yet been established, however, how inflammatory parameters change after surgery when spinal instruments have been inserted into the body. METHODS: For this study, two groups of patients were examined: a control group that underwent spinal decompression surgery without instrumentation (n = 36) and another group that underwent spinal decompression and fusion surgery with spinal instrumentation (n = 37). The erythrocyte sedimentation rate, C-reactive protein, white blood cell count, and body temperature were recorded 1 day before surgery and on days 0 to 4, 7, 11, 14, 21, 28, and 42 after surgery. RESULTS: Inflammatory indexes (i.e., C-reactive protein, erythrocyte sedimentation rate, white blood cell count, and body temperature) were significantly higher for the surgery with instrumentation than for the spinal decompression surgery without instrumentation. Multiple regression analysis showed that C-reactive protein and erythrocyte sedimentation rate peaks significantly correlated with the use of instrumentation (C-reactive protein: P = 0.000257, erythrocyte sedimentation rate: P = 0.000132). In the patients with infection after spinal instrumentation surgery, C-reactive protein, white blood cell count, and body temperature started to increase again 4 to 11 days after surgery. The elevation of erythrocyte sedimentation rate levels was prolonged. CONCLUSIONS: Erythrocyte sedimentation rate and C-reactive protein display a significantly higher reaction after spinal surgery with instrumentation. Renewed elevation of C-reactive protein, white blood cell count, and body temperature after postoperative days 4 to 7 may be a critical sign of postoperative infection.

Adult↗
PubMed2001

Cloning and functional analysis of two gibberellin 3 beta -hydroxylase genes that are differently expressed during the growth of rice.

We have cloned two gibberellin (GA) 3 beta-hydroxylase genes, OsGA3ox1 and OsGA3ox2, from rice by screening a genomic library with a DNA fragment obtained by PCR using degenerate primers. We have used full-scan GC-MS and Kovats retention indices to show function for the two encoded recombinant fusion proteins. Both proteins show 3 beta-hydroxylase activity for the steps GA(20) to GA(1), GA(5) to GA(3), GA(44) to GA(38), and GA(9) to GA(4). In addition, indirect evidence suggests that the OsGA3ox1 protein also has 2,3-desaturase activity, which catalyzes the steps GA(9) to 2,3-dehydro-GA(9) and GA(20) to GA(5) (2,3-dehydro GA(20)), and 2 beta-hydroxylase activity, which catalyzes the steps GA(1) to GA(8) and GA(4) to GA(34). Molecular and linkage analysis maps the OsGA3ox1 gene to the distal end of the short arm of chromosome 5; the OsGA3ox2 gene maps to the distal end of the short arm of chromosome 1 that corresponds to the D18 locus. The association of the OsGA3ox2 gene with the d18 locus is confirmed by sequence and complementation analysis of three d18 alleles. Complementation of the d18-AD allele with the OxGA3ox2 gene results in transgenic plants with a normal phenotype. Although both genes show transient expression, the highest level for OsGA3ox1 is from unopened flower. The highest level for OsGA3ox2 is from elongating leaves.

Amino Acid Sequence↗
PubMed2001

Beta2-adrenergic receptor/cyclic adenosine monophosphate (cAMP) leads to JNK activation through Rho family small GTPases.

Gi- and Gq-coupled G protein-coupled receptors (GPCRs) have been shown to activate c-Jun N-terminal kinase (JNK), a subfamily of mitogen-activated protein kinases (MAPKs), through Rho family small GTPases in mammalian cells. We investigated the signaling pathway linking the Gs-coupled beta2-adrenergic receptor with JNK, using smooth muscle DDT1 MF-2 cells, which natively express the beta2-adrenergic receptor. Stimulation of the beta2-adrenergic receptor activated JNK in a time-dependent manner, and a cell-permeable cyclic adenosine monophosphate analogue (8-Br-cAMP) activated JNK. The beta2-adrenergic receptor- or 8-Br-cAMP-induced activation of JNK required Rho family small GTPases. Also, the beta2-adrenergic receptor or 8-Br-cAMP induced activation of Rho family small GTPases. These results demonstrate that the beta2-adrenergic receptor/cAMP leads to JNK activation through Rho family small GTPases in DDT1 MF-2 cells. Activation of Rho family small GTPases may provide a common step in GPCR-mediated JNK activation.

Animals↗
PubMed2001

Mouse hepatocyte growth factor activator inhibitor type 1 (HAI-1) and type 2 (HAI-2)/placental bikunin genes and their promoters.

Hepatocyte growth factor (HGF) activator inhibitor type 1 (HAI-1) and type 2 (HAI-2) were recently discovered as specific inhibitors of HGF activator. Each of them contains two Kunitz-type serine protease inhibitor domains and a transmembrane domain, so that their overall structures are similar to each other. In this study, mouse genes encoding HAI-1 and HAI-2 were cloned by screening of a mouse genomic bacterial artificial chromosome library and by polymerase chain reaction of mouse genomic DNA, respectively. The genes (mHAI-1 and mHAI-2) were defined to consist of 11 and eight exons spanning 11 kbp and 9.5 kbp, respectively. Neither a TATA nor CAAT box was found in 5'-flanking regions of both genes and no apparent homologous portion was observed between mHAI-1 and mHAI-2 promoter regions. Promoter assay of mHAI-1 and human HAI-1 revealed that the potential binding sites of a complex of Egr-1-3 and Sp1, which was well-conserved between human (-42 to -58) and mouse (-44 to -57), might be a key portion of its transcriptional regulation to function as not only house-keeping but also early responsive genes.

Animals↗
PubMed2001

A long-lasting facilitation of hippocampal neurotransmission via a phospholipase A2 signaling pathway.

Phospholipase A2, which is linked to a protein kinase C pathway, hydrolyzes phosphatidylcholine into cis-unsaturated free fatty acids and lysophosphatidylcholine (lysoPC). The present study investigated the effect of the free fatty acids, such as arachidonic, oleic, linoleic, and linolenic acid, and lysoPC on neurotransmission by monitoring population spikes (PSs) from the granular cell layer of rat hippocampal slices. All the free fatty acids and lysoPC examined here gradually increased PS amplitude to a different extent, the effect being evident 60 min after treatment. No significant synergistic enhancement in the PS amplitude was not induced by arachidonic acid following oleic acid, linoleic acid or lysoPC. The results of the present study, thus, demonstrate that phospholipase A2-linked free fatty acids and lysoPC are employed in the sustained facilitation of hippocampal neurotransmission, suggesting a significant role of a phospholipase A2 signaling pathway in the neuroplasticity.

Animals↗