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Biomedical subjects

H Ide

Publications and source records attributed to H Ide.

At least 37 records · Page 2Linked to original sources
PubMed1998

Multiple digit formation in Xenopus limb bud recombinants.

We prepared recombinant limb buds of Xenopus tadpoles by grafting a mesenchyme mass of the hindlimb bud. The Xenopus recombinant limb buds with dissociated and reaggregated mesenchyme developed more than 30 digits with cartilage segmentation, while those with undissociated mesenchyme developed a limb with normal cartilage pattern. Before the formation of multiple digits, a patchy expression pattern of fgf-8, an AER marker, was observed in the distal region of recombinant limb buds. shh, a ZPA (zone of polarizing activity) marker, was expressed broadly in the distal region of recombinants. Recombinant limb buds with the reaggregated mesenchyme of anterior halves formed anterior digits with claws, and those with the mesenchyme of posterior halves formed posterior digits without claws. The temporal and spatial changes in the potency of multiple digit formation are discussed with reference to the regenerative capacity of Xenopus limb buds.

Animals↗
PubMed1998

Cell-cell adhesion in limb-formation, estimated from photographs of cell sorting experiments based on a spatial stochastic model.

We developed a new method to estimate the magnitude of differential cell-cell adhesion of two tissues based on the spatial patterns in cell-sorting experiments, and applied it to experimental data on progress-zone cells of avian limb bud at stages 20-26. The change in cell distribution in the experiment was recorded, and statistics qB/B for the degree of cell sorting was calculated from the photographs. Based on extensive computer simulations of spatial Markov processes on a 2-D lattice, we derived a formula for qB/B increasing with time. Using least square fitting, differential adhesion A and cell motility m are estimated from the time series data of qB/B obtained from the experiment. The estimated A was close to 0 (the spatial pattern remained random) if the mixed cells were from two tissues of the same stage. If the mixed cells were from different stages, and the estimated A was positive (cell sorting occurred). Estimated A increased with the difference in the stage number of the two tissues from which the cells were sampled. This result can be explained both by the stage-specific change in adhesion molecules and by a linear increase (or decrease) in the amount of adhesion molecules on cell surface.

Animals↗
PubMed1998

[Two cases of surgical treatment of recrudescent Stanford type A dissection after early thrombogenic closure without intimal tear].

We reported two cases of thrombosed, Stanford A type acute aortic dissection, initially without intimal tear, later operated upon because of recrudescence. They admitted to our hospital with the symptoms of aortic dissection. Early examination of computed tomography and angiography demonstrated thrombosed type A aortic dissection showing a normal aortic figure, although accompanied by pericardial effusion, that was drainaged. Under strict BP control, however, repeat CT examination revealed recrudescent dissection of ascending aorta, making dissecting aneurysms. Graft replacement of ascending aorta was performed, on the 55th and 153th day after admission, and they were discharged.

Aged↗
PubMed1998

Interleukin-13 down-regulates the expression of neutrophil-derived macrophage inflammatory protein-1 alpha.

OBJECTIVE AND DESIGN: To determine whether interleukin-13 (IL-13) possesses anti-inflammatory properties with respect to polymorphonuclear neutrophils (PMNs). Effects of IL-13 on production of the chemokine, macrophage inflammatory protein-1 alpha (MIP-1alpha), by PMNs were analyzed. SUBJECTS: Human peripheral blood PMNs obtained from healthy volunteers. METHODS: PMNs were stimulated by lipopolysaccharide (LPS) and/or IL-13 for selected periods of time, and MIP-1alpha expression was assessed by ELISA and Northern blot analysis. RESULTS: IL-13 suppressed expression and production of PMN-derived MIP-1alpha mRNA and protein in a dose- and time-dependent manner. Inhibition of protein synthesis caused significant enhancement of MIP-1alpha mRNA expression. The inhibitory activity of IL-13 was abrogated, however, in the presence of cycloheximide, suggesting that IL-13's effect was via synthesis of de novo repressor protein(s). CONCLUSIONS: PMN-derived chemokines are regulated by both proinflammatory and immunomodulatory cytokines. The coordinated production of these substances is likely to be important in the orchestration of inflammatory and immune responses.

Blotting, Northern↗
PubMed1998

Phorbol ester-induced production of prostaglandin E2 from phosphatidylcholine through the activation of phospholipase D in UMR-106 cells.

To determine the effects of 12-O-tetradecanoylphorbol-13-acetate (TPA) on phospholipase D (PLD) activity in osteoblast-like UMR-106 cells, we used cells prelabeled with [3H] myristic acid or [3H] arachidonic acid, which were preferentially incorporated to phosphatidylcholine. The treatment of [3H] myristate-labeled cells with TPA in the presence of 1% ethanol caused a dose-dependent formation of [3H] phosphatidylethanol (PEt), a product specific to PLD, suggesting an activation of this enzyme. Pretreatment of the cells with protein kinase C (PKC) inhibitors (GF109203X, staurosporine or H-7) abolished the TPA-dependent formation of PEt. The PEt formation in response to TPA treatment was not observed after the pretreatment of the cells with TPA to downregulate PKC. These results suggest the involvement of PKC in the TPA-induced activation of PLD. With [3H] arachidonate-labeled cells, TPA treatment in the absence of ethanol resulted in the liberation of [3H] arachidonic acid, which was gradually converted to prostaglandin E2 (PGE2), but the accumulations of [3H] phosphatidic acid (PA) and [3H] diacylglycerol (DAG) were very small and temporary. In contrast, PA was linearly accumulated following TPA treatment, when the cells were pretreated with an inhibitor of phosphatidate phosphohydrolase (PAP), propranolol, with no accumulation of either DAG or arachidonic acid. The TPA treatment of the cells pretreated with a DAG lipase inhibitor, RHC-80267, caused the generation of DAG after a lag period of approximately 5 min, with a very small and temporary accumulation of PA. The TPA treatment of cells pretreated with a cyclooxygenase (COX) inhibitor, indomethacin, blocked the PGE2 production. The TPA-induced PGE2 production was not affected by the pretreatment of cells with a phospholipase A2 inhibitor, p-bromophenacylbromide, or with a phospholipase C inhibitor, D-609. TPA also stimulated PGE2 production in osteoblastic cells that were enzymatically isolated from adult rat calvaria, and the experiments with lipid metabolizing enzyme inhibitors gave the same profile of inhibition of TPA-induced PGE2 production as was observed in UMR-106 cells. These results suggest that PA formed as a consequence of the activation of PLD by TPA is rapidly converted to arachidonic acid via a PAP/DAG lipase pathway, followed by a gradual conversion of arachidonic acid to PGE2 by COX in both UMR-106 cells and isolated adult osteoblastic cells, and that neither phospholipase A2 nor phospholipase C is involved in the TPA-induced PGE2 production. To the best of our knowledge, this is the first report that shows that the activation of PKC in osteoblastic cells leads to the production of PGE2 via a PLD/PAP/DAG lipase/COX pathway.

Animals↗
PubMed1998

Juxtaposition of two heterotypic monolayer cell cultures of chick limb buds.

In chick limb buds, mesenchymal cells of the progress zone (PZ-cells) at different developmental stages segregate one from the other in mixed cell cultures, suggesting they have different cell affinity. In order to learn the possible roles of such differences in the cells, two heterotypic leg PZ-cell populations (cells from stages 25/26 and 20/21) in vitro were juxtaposed to allow them to form the boundary. A method with double cylindrical columns was used to make adjoining monolayer cell cultures. It was shown that heterotypic juxtaposition produced two chondrogenic patterns along the boundary: aggregates of chondrocytes formed by stage 20/21 PZ-cells and a chondrocyte-free band formed by those at stage 25/26. Juxtaposition of PZ-cells and proximal cells also formed these patterns, while that between cells from anterior and posterior PZ formed indistinct patterns along the boundary. Homotypic PZ-cell juxtaposition did not produce these patterns. The results suggest that different cell affinity has a role in the segmentation of cartilage patterns at a point along the proximodistal axis, as well as a role in retaining cells in one area so as not to be recruited to other condensation areas.

Animals↗
PubMed1998

Apical ectodermal ridge induction by the transplantation of En-1-overexpressing ectoderm in chick limb bud.

In the early chick embryo, the dorsal ventral (DV) boundary organizes the apical ectodermal ridge (AER) structure in the limb bud field. Here it is reported that Engrailed-1 (En-1), a homolog of the Drosophila segment polarity gene engrailed expressed in the ventral limb ectoderm, participates in AER formation at the DV boundary of the limb bud. Restricted ectopic expression of En-1 in the dorsal side of the limb bud by transplantation of En-1-overexpressing ectoderm induces ectopic AER at the boundary of En-1-positive and -negative cells. The results suggest that En-1 is involved in AER formation at the DV boundary of the limb bud.

Animals↗
PubMed1998

Shh, Bmp-2 and Hoxd-13 gene expression in chick limb bud cells in culture.

The anteroposterior axis of the vertebrate limb bud is determined by signals from the zone of polarizing activity (ZPA). Sonic hedgehog (Shh) is expressed in the posterior mesoderm, which corresponds closely to ZPA activity. Moreover, Bmp-2 and HoxD genes are expressed in the broader posterior mesoderm, and it is thought that the ZPA signaling pathway consists of these gene products. Limb outgrowth and patterning, including expression of these genes, depend on the apical ectodermal ridge (AER). Fibroblast growth factors (FGF) have been identified as candidates for signal molecules from the AER. To further understand the ZPA signaling pathway and the participation of FGF, expressions of these genes were examined by reverse transcription-polymerase chain reaction in chick limb bud cells cultured with FGF-4. The present results indicate that FGF-4 cannot maintain Shh expression but can maintain Hoxd-13 expression in cultured posterior cells; moreover, Bmp-2 is expressed independently of FGF-4. These results suggest that Bmp-2 and Hoxd-13 expressions do not require a continuous expression of Shh. Further, it was demonstrated that posterior cells cultured with FGF-4 recovered Shh expression when grafted to the limb bud, indicating that FGF-4 maintains not Shh expression itself but competence of Shh expression.

Animals↗
PubMed1998

Coordinated expression of Hoxa-11 and Hoxa-13 during limb muscle patterning.

The limb muscle precursor cells migrate from the somites and congregate into the dorsal and ventral muscle masses in the limb bud. Complex muscle patterns are formed by successive splitting of the muscle masses and subsequent growth and differentiation in a region-specific manner. Hox genes, known as key regulator genes of cartilage pattern formation in the limb bud, were found to be expressed in the limb muscle precursor cells. We found that HOXA-11 protein was expressed in the premyoblasts in the limb bud, but not in the somitic cells or migrating premyogenic cells in the trunk at stage 18. By stage 24, HOXA-11 expression began to decrease from the posterior halves of the muscle masses. HOXA-13 was expressed strongly in the myoblasts of the posterior part in the dorsal/ventral muscle masses and weakly in a few myoblasts of the anterior part of the dorsal muscle mass. Transplantation of the lateral plate of the presumptive wing bud to the flank induced migration of premyoblasts from somites to the graft. Under these conditions, HOXA-11 expression was induced in the migrating premyoblasts in the ectopic limb buds. Application of retinoic acid at the anterior margin of the limb bud causes duplication of the autopodal cartilage and transformation of the radius to the ulna, and at the same time induces duplication of the muscle pattern along the anteroposterior axis. Under these conditions, HOXA-13 was also induced in the anterior region of the ventral muscles in the zeugopod. These results suggest that Hoxa-11 and Hoxa-13 expression in the migrating premyoblasts is under the control of the limb mesenchyme and the polarizing signal(s). In addition, these results indicate that these Hox genes are involved in muscle patterning in the limb buds.

Animals↗
PubMed1998

Protective roles of bacterioruberin and intracellular KCl in the resistance of Halobacterium salinarium against DNA-damaging agents.

Halobacterium salinarium, a member of the extremely halophilic archaebacteria, contains a C50-carotenoid namely bacterioruberin. We have previously reported the high resistance of this organism against the lethal actions of DNA-damaging agents including ionizing radiation and ultraviolet light (UV). In this study, we have examined whether bacterioruberin and the highly concentrated salts in this bacterium play protective roles against the lethal actions of ionizing radiation, UV, hydrogen peroxide, and mitomycin-C (MMC). The colourless mutant of H. salinarium deficient in bacterioruberin was more sensitive than the red-pigmented wild-type to all tested DNA-damaging agents except MMC. Circular dichroism (CD) spectra of H. salinarium chromosomal DNA at various concentrations of KCl (0-3.5 M) were similar to that of B-DNA, indicating that no conformational changes occurred as a result of high salt concentrations. However, DNA strand-breaks induced by ionizing radiation were significantly reduced by the presence of either bacterioruberin or concentrated KCl, presumably due to scavenging of free radicals. These results suggest that bacterioruberin and intracellular KCl of H. salinarium protect this organism against the lethal effects of oxidative DNA-damaging agents.

Carotenoids↗
PubMed1998

Induction of fragile sites by fluorodeoxyuridine and caffeine accompanies with misincorpolation of endogenous uridine nucleotide into DNA of feline fibroblasts.

Fluorodeoxyuridine, an inhibitor of thymidylate synthetase, is known to induce chromosomal fragile sites. The drug treatment may cause deprivation of intracellular thymidine nucleotide pool followed by a serious imbalance of deoxynucleotide pool. Though the stress is probably related to the induction of folate-sensitive fragile sites, the exact mechanism is still to be investigated. The present study has been carried out to test the possibility that the fragile sites are originated, at least in part, from incorpolated uracil residues. The incorpolated uracil residue can be detected by a novel assay for abasic sites after treatment with uracil-DNA N-glycosylase (UDG). About 2.7 abasic sites per 10(4) nucleotides were detected in the DNA extracted from feline fibroblasts after the treatment with FUdR and caffeine. By digesting the DNA with UDG prior to the assay, significant increase in the number of abasic sites were observed. These results indicate that the large amount of uracil residues are present in the feline fibroblast DNA under the condition which induces chromosomal fragile sites.

Animals↗
PubMed1998

CYFRA 21-1 as a tumor marker for squamous cell carcinoma of the esophagus.

This study assessed the clinical value of CYFRA 21-1 in comparison with squamous cell carcinoma antigen (SCC-Ag), carcinoembryonic antigen (CEA), and carbohydrate antigen 19-9 (CA19-9) in patients with esophageal squamous cell carcinoma. In 112 primary cancer patients, the diagnostic sensitivity of CYFRA 21-1 (33.9%) was superior to SCC-Ag (28.6%), CEA (12.5%), and CA19-9 (6.3%). Levels of CYFRA 21-1 were closely correlated with TNM stage and wee below the cutoff value in all 21 patients with stage I disease. All 38 patients with a CYFRA 21-1 level over the cutoff value among the 80 patients who underwent esophagectomy had lymph node metastases (pN1). A correlation was found between CYFRA 21-1 levels and clinical response in serial measurements of 21 patients who received chemotherapy or chemo radiotherapy. Our findings suggest that CYFRA 21-1 is not useful for diagnosis, but that it is valuable for monitoring the efficacy of therapy.

Adult↗
PubMed1998

Effects of FGFs on the morphogenic potency and AER-maintenance activity of cultured progress zone cells of chick limb bud.

The apical mesodermal region of chick limb buds (progress zone, PZ) which is essential for limb pattern formation contains uncommitted cells that change their positional values instructed by the apical ectodermal ridge (AER). Reciprically, the PZ cells maintain the AER activity. FGF-2 and FGF-4 can substitute for the AER to maintain normal outgrowth and gene expression in the limb bud. We examined the effects of FGF on the maintenance of PZ cells characteristics in culture by making recombinant limbs with anterior PZ cells that were pre-cultured in the presence of FGF-2 or FGF-4 and analyzed their morphogenic potency and responsiveness to positional cues arising from the zone of polarizing activity (ZPA). The limb buds expressed distal Hox genes and could form a segmented digit. Recombinant limb buds consisting of anterior PZ cells cultured without FGF failed to express Hox genes and formed instead a small cartilage nodule. These results indicate that addition of FGF-2 or FGF-4 to cultured PZ cells maintains their competence for Hox gene expression and digit formation, but not their responsiveness to positional cues from the ZPA. We also found that when anterior PZ cells which had been pre-cultured with FGF-2 or FGF-4 were implanted underneath the AER, they could maintain Fgf-8 expression in the AER, whereas this expression was not detected in the AER on the grafted anterior PZ cells that had been pre-cultured without FGF, indicating that FGF maintains AER-maintenance activity of PZ cells in culture.

Animals↗
PubMed1998

[The role of endoscopic ultrasonography for gastric cancer in the cardiac area].

In order to select the most appropriate treatment for gastric cancer in the cardiac area, precise staging by determining the depth of cancer invasion, and esophageal invasion, and lymph node metastases is important. In this paper, diagnosis of these factors using endoscopic ultrasonography (EUS) and its accuracy are discussed. In 121 cases of gastric cancer in the cardiac area, EUS was performed and the findings compared with the pathological diagnosis. The depth of cancer invasion was accurately determined in 60% of mucosal cancer cases, 83% of cancer invading the submucosa, 50% of cancer invading the muscularis propria or the subserosa, 86% of cancer invading the serosa, 45% of cancer invading other organs, and overall accuracy was 77%. In cases of esophageal invasion sensitivity was 98%, specificity 93%, and overall accuracy 94%. In cases of lymph node metastasis specificity was 78%: 86% for N1 and 72% for N2. EUS therefore has an important role in diagnosis and selection of treatment.

Cardia↗
PubMed1998

[A case report of selective IgA deficiency in rheumatoid arthritis and anti-IgA antibody induced anaphylactic transfusion].

We described a case of rheumatoid arthritis (RA) with selective IgA deficiency. A 69 year-old female with RA was admitted because of gall bladder cancer, and also had selective IgA deficiency which serum IgA level was less than 5.0 mg/dl, and IgA 1 and IgA 2 subclasses were not detected. Prior to the operation, she was given red cell compatible blood transfusion because of severe anemia. After 30 min of transfusion, she developed chill, nausea, vomiting and hypotension. These anaphylactic reactions might be induced by the presence of anti-IgA antibody, since the level of this antibody titers in her serum was elevated, assessed by the methods of ELISA and Western blotting. Although a case of RA associated with selective IgA deficiency, and also with elevated serum anti-IgA antibody level is extremely uncommon, attention should be paid to the presence of anti-IgA antibody in patients with selective IgA deficiency to avoid any unexpected anaphylactic reactions.

Aged↗