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Biomedical subjects

K Sugimoto

Publications and source records attributed to K Sugimoto.

At least 469 records · Page 26Linked to original sources
PubMed1991

Expression of stress fibers in bullfrog mesothelial cells in response to tension.

The relationship between stress fibers and tension in mesothelial cells of the bullfrog small intestine was examined by fluorescence cytochemistry using en face mesothelial cell preparations. In nontreated controls, actin revealed by rhodamine-phalloidin staining was localized only along the margins of the mesothelial cells. On the other hand, many stress fibers were formed in the mesothelial cells within 5-7 min after stretching of the intestinal wall in a given direction. The orientation of stress fibers within the cells was coincident with the direction of the tension applied. These cytoplasmic fibers disappeared almost completely from the mesothelial cells within 30 min after the release of tension. According to a difference in the intensity of tension necessary for stress fiber expression, the intestinal mesothelial cells were classified into two groups. Furthermore, cells containing stress fibers in each group showed a rapid increase in number once a given value of tension was applied. The present results indicate that the mesothelial cells of bullfrog small intestine may develop stress fibers to counteract tension exerted on the intestinal wall. Such stress fibers may serve to maintain cellular integrity by strengthening the cellular attachment to subepithelial tissue.

Animals↗
PubMed1991

Hierarchical regulation of interleukin production: induction of interleukin 6 (IL-6) production from bone marrow cells and marrow stromal cells by interleukin 3 (IL-3).

IL-3 stimulated the production of IL-6 from a bone marrow-adherent cell population, macrophages and from hemopoietic supportive stromal cell lines. It also induced IL-6 production from a stem cell-enriched population of bone marrow cells which did not produce IL-6 without stimulation. In contrast, stimulation with IL-6 of all the cell populations studied in the present experiments did not induce IL-3 production. These results indicate a hierarchical network in the regulation of interleukin production, and existence of a positive feedback mechanism; IL-3 induces IL-6 production which in turn stimulates stem cells into cycle and induces stem cells to respond to IL-3.

Animals↗
PubMed1991

Prevention of genetic resistance to bone marrow allografts by reticuloendothelial system blockade.

Agents which are toxic to macrophages such as silica and caragheenan suppress genetic resistance to bone marrow allografts. However, these agents may also be toxic to other tissues and cannot be used for the establishment of long-term bone marrow chimerism. In this study, we used chemically insert carbon particles to blockade phagocytic cells, and succeeded in carrying out bone marrow allografts. Long-term survival of the recipient mice after bone marrow transplantation (BMT) was achieved without apparent evidence of graft-versus-host reaction (GVHR), although T-cells were not depleted in donor marrow cells. The hemopoietic system of the recipient mice was replaced by that of donor origin. These results indicate that phagocytic cells play an essential role, probably as effector cells in genetic resistance to bone marrow allograft.

Animals↗
PubMed1991

Establishment of a sarcoma cell line, MS-K, expressing Ki-ras proto-oncogene product from mouse bone marrow stromal cells.

A sarcoma cell line, MS-K, was established from a long-term culture of mouse bone marrow stromal cells. When inoculated into syngeneic 3HC/HeNS1c mice, the cells formed large necrosis-free tumors, but there were no apparent changes in hematological features or in general conditions of tumor-bearing mice. The tumor had a fibroblastic appearance, was well vasculated and differentiated into adipocytes at the peripheral region. Immunohistochemical studies revealed that the cells were positive for vimentin and S-100 protein, indicating that the cells were of lipoblast origin. A significant amount of fat-deposition was induced in the cytoplasm of the cells when MS-K cells were cultured in the presence of hydrocortisone and insulin. Antibody-staining for oncogene products showed that the cells were negative for c-fos but strongly positive for Ki-ras. MS-K cells did not adhere hemopoietic stem cells or support their proliferation, which contrasts with previously established MS-1, which is a hemopoietic-supportive and stem cell-adherent lipoblast cell line. These properties of MS-K and MS-1 should be useful in the identification of the surface structures for stem cell anchorage.

Animals↗
PubMed1991

A nuclear factor NF-GM2 that interacts with a regulatory region of the GM-CSF gene essential for its induction in responses to T-cell activation: purification from human T-cell leukemia line Jurkat cells and similarity to NF-kappa B.

Activation of T cells by antigen, lectin, or a combination of phorbol-12-myristate acetate (PMA) and calcium ionophore (A23187) leads to the induction of genes for a set of lymphokines, including granulocyte-macrophage colony-stimulating factor (GM-CSF). We demonstrated in earlier studies that the upstream region of the mouse GM-CSF promoter at positions between -95 and -73 is essential for transcriptional activation in response to PMA/A23187. This region contains two DNA-binding motifs, GM2 and GC-box. The GM2 sequence (GGTAGTTCCC) is recognized by an inducible factor NF-GM2; the other (CCGCCC) by constitutive factors A1, A2, and B. To elucidate the mechanism of GM-CSF gene activation, we have purified the inducible factor NF-GM2 from the nuclear extract of stimulated Jurkat cells on the basis of specific DNA-binding activity. The purified NF-GM2 consists of 50 (p50) and 65 kDa (p65) polypeptides and has a binding activity specific for both the GM-CSF and immunoglobulin kappa (GGAAAGTCCC) enhancers. Electrophoretically purified p50 alone can form a protein-DNA complex, but in the mixture, p50 associates preferentially with p65 to form the NF-GM2 complex. In addition, p65 gave per se, with low affinity, a protein-DNA complex that migrated more slowly than native NF-GM2 complex. Furthermore, an antiserum against KBF1 (identical to 50 kDa NF-kappa B protein) reacted with the p50 of NF-GM2, indicating that the NF-GM2 polypeptide cannot be immunologically differentiated from the 50 kDa subunit of NF-kappa B. The purified NF-GM2 activated in vitro transcription from the kappa B enhancer, while it failed to stimulate transcription from the GM-CSF promoter harboring the GM2 sequence. This suggests that the activation mechanism of the GM-CSF gene through the GM2/GC-box sequence is different from that of genes carrying the kappa B enhancer alone.

Base Sequence↗
PubMed1991

Measurement of plasma total renin by the anti-human renin monoclonal antibodies.

The authors evaluated the assay performances and clinical usefulness of a newly developed solid phase radioimmunoassay (RIA) for total renin concentration (TRC) in human plasma. The direct total renin RIA was performed by a sandwich technique with a pair of anti-human renin monoclonal antibodies. Renin activation with trypsin did not change TRC. The RIA showed satisfactory assay performances and demonstrated full compatibility with a direct RIA-kit for active renin concentration (ARC) in human plasma. The values of TRC were 105.3 +/- 8.6 pg/mL in normal subjects and 136.5 +/- 14.6 pg/mL in patients with essential hypertension. The values of TRC and the ratios of ARC to TRC were high in patients with renovascular hypertension and were low in patients with primary aldosteronism. Although the TRC value in diabetic patients was 134.4 +/- 14.8 pg/mL, the ratio of ARC to TRC was low. The RIA procedure was simple since prior purification or activation of renin was not required. These results suggest that the total renin RIA and its combined use with the active renin RIA may be helpful in understanding the renin-angiotensin system in human plasma.

Antibodies, Monoclonal↗
PubMed1991

A pathologic study on the inhibitory effects of a herbal medicine against the glomerular lesion induced by Agkistrodon venom in mice.

The inhibitory effects of a prescription of herbal medicine, tentatively named P-3, were studied pathologically in an experimental model of the glomerular lesion induced by purified snake Agkistrodon acutus venom proteinase (Ac1-P) in mice. Ac1-P was intravenously inoculated at a single LD50 dose. In the treated group, mice were intraperitoneally injected with an extract of P-3 at a designated time once every two days from 2 days before to 1 week after Ac1-P inoculation. The control group mice were injected with saline instead of P-3. In the control group, the main pathologic changes within 48 hrs after inoculation were pulmonary and gastrointestinal tract hemorrhage and renal petechiae with hematuria. The kidney microscopically showed cystic transformation of the glomerular capillary tufts. followed by occlusive thrombosis. One week after inoculation, the glomerular lesions were mostly replaced by proliferative or proliferative-sclerosing changes with occasional crescent formation. Early signs of tubular atrophy accompanying the glomerular changes were observed. In the P-3 treated mice surviving 48 hrs and 1 week, the changes observed in the controls were markedly inhibited, although P-3 treated mice dying earlier than 30 hrs exhibited hemorrhagic changes similar to controls. This indicated that the herbal medicine had efficacy against the tissue injuries induced by Ac1-P as a proteolytic enzyme.

Angiography↗
PubMed1991

Tarsal tunnel syndrome. Causes and results of operative treatment.

From 1975 to 1988, operative treatment was performed on 50 feet in 45 patients with tarsal tunnel syndrome. The causes of this syndrome were correlated with operative findings and included ganglia in 18, and a bony prominence from talocalcaneal coalition in 15. Five feet had sustained an injury, tumours were found in three and there was no obvious cause in nine. In most cases in need of operative treatment, there was a space-occupying lesion. Classifying the results according to causes, those with coalition or a tumour fared better, and idiopathic and traumatic cases had a worse outcome. In cases with a definite lesion, an excellent result can be expected from surgical treatment carried out soon after onset of the condition.

Adolescent↗
PubMed1991

A rapid isolation of the unknown 5'-flanking sequence of human CENP-B cDNA with polymerase chain reactions.

We rapidly and efficiently isolated the 5'-region of cDNA encoding the N-terminal region of human centromere antigen B (CENP-B) including an ATG methionine codon by polymerase chain reactions (PCR). The unknown 5'-flanking sequence of the cDNA was amplified using an adaptor-sequence ligated to the 5' end as a universal primer sequence. To locate the target fragments, we did an additional PCR with another set of two internal primers using samples of the size-fractionated products as templates, rather than using the conventional hybridization procedure. This approach can further be applied to the analysis of other unknown flanking sequences of cDNA or genomic DNA.

Autoantigens↗
PubMed1991

[Right ventricular infarction following acute inferior myocardial infarction confirmed by dual isotope single photon emission computed tomography (SPECT) of [99mTc] pyrophosphate and [201Tl] chloride].

A 56-year-old man, complaining of severe substernal chest pain, was admitted. In this patient, right ventricular infarction following by acute inferior myocardial infarction was suggested by serial enzymes, electrocardiogram, echocardiogram, and hemodynamic data, but it was not confirmed. A dual isotope SPECT with 99mTc-pyrophosphate and 201Tl-Cl was performed and color-coded tomograms were obtained. It showed a characteristic image of right ventricular infarction, especially in the short axis view right ventricular infarction looked like shape of a tongue which protruded from left ventricle. We concluded that though the diagnosis of right ventricular infarction is difficult, a dual isotope SPECT is a useful method because it shows a characteristic image.

Diphosphates↗
PubMed1991

[Antigenic determinants on ovalbumin and ovomucoid: comparison of the specificity of IgG and IgE antibodies].

To delineate the antigenic determinants on ovalbumin (OA) and ovomucoid (OVM) recognized by specific IgG and IgE antibodies in sera from patients with allergy to hen's egg, we studied the binding activities of IgG and IgE antibodies to native OA or OVM and seven different OA or OVM preparations, i.e. heated OA or OVM (100 degrees C for 3 min and 80 degrees C for 30 min) or 0.3 M NaOH, dithiothreitol (DTT), sodium dodecyl sulfate (SDS), 6 M urea or HCl treated OA or OVM. Eight patients with IgE anti-OA antibodies and 12 patients with IgE anti-OVM antibodies were used in these studies. The binding activities of IgG and IgE antibodies to physically or chemically denatured OA were partially decreased compared with those to native OA, whereas IgG and IgE antibodies in sera from patients bound well to denatured OVM with similar binding activities to native OVM. These results strongly suggest that antibodies to OA recognize partially conformational antigenic determinants on OA, whereas antibodies to OVM mainly recognize sequential antigenic determinants on OVM, and that antigenic determinants of OVM recognized by antibodies in sera from patients are more stable than those of OA under these denaturation conditions. In addition, the binding activities of IgE antibodies to denatured OA or OVM were significantly different from those of IgG antibodies to these OA or OVM, suggesting that the specificities of IgE antibodies to OA or OVM may be different from those of IgG antibodies to OA or OVM.

Adolescent↗
PubMed1991

[Clinical evaluation of nonseminomatous testicular germ cell tumors].

We treated 26 patients with nonseminomatous germ cell tumors (NSGCT) between January 1976 and March 1989. Histologically, 7 were embryonal carcinoma (27%), 4 were teratoma (15%), 2 were yolk sac tumor (8%), 10 were teratocarcinoma (38%) and 3 were other mixed tumors. As regards staging, 18 belonged to stage I (69%), 1 to stage II A (4%), 1 to stage IIB (4%), 1 to stage IIIA, 2 to stage III B1 (8%) and 3 to stage III B2 (12%). Patients in stage I were treated by orchidectomy with lymphadenectomy and occasionally chemotherapy before 1984, resulting in a 100% 5-year survival. However, after 1985, 5 cases in stage I were treated by orchidectomy alone according to a watch-and-see policy. Two cases among them relapsed within two years and both of them contained immature teratoma elements. Six patients with metastatic tumor were treated with PVB therapy of which response rate was 66.7%. The total 5-year survival rate of patients in stage I, II and III was 100%, 50%, 50%, respectively and that in overall cases was 84.6%.

Adult↗
PubMed1991

Symptomatic talocalcaneal coalition. Its clinical significance and treatment.

The clinical significance of symptomatic talocalcaneal coalition was described subjectively, objectively, and identified roentgenographically after examining 67 feet of 42 patients between 1977 and 1987. Computed tomographic examinations, conducted on 29 of 42 patients, were useful in recognizing the extent of coalition, the condition of union, and the postoperative results. Tarsal tunnel syndrome was present in 23 feet with the coalition. Thirty-one feet (24 patients) were treated conservatively and 36 feet (29 patients) surgically. Of the surgically treated feet, the coalition was excised in 33 and talocalcaneal fusion was performed in three. Follow-up examinations were performed at an average of 5.3 years (range, 2.25-11.2 years). In the excision group, the results were excellent in 24 feet, good in seven, and fair in two. The results were good in three feet treated by arthrodesis.

Adolescent↗
PubMed1991

Application of renal microangiography to normal and diseased kidneys of cattle and mice.

Use of microangiography is now essential for the study of microcirculation in various organs. Renal microangiographic studies have been reported in rats, rabbits, dogs, human beings, and mice. However, we could not find any report on use of the technique in cattle, despite high incidence of renal disease in that species. The perfusion technique used in mice was improved over that of our previous report, and was applied to normal and diseased bovine kidneys. For the microangiographic technique, composition of the contrast medium, pressure of the injection, duration of perfusion, and washing of kidneys with heparinized saline solution before perfusion are important. In cattle, 1- to 2-mm-thick sections of the kidneys were generally necessary to observe renal vasculature: arcuate and interlobular arteries, afferent arterioles, and glomerular capillaries. In normal bovine kidneys, the angiographic and microangiographic findings were easily recognized as normal, compared with those of normal mice. In affected bovine kidneys, which histologically represented glomerulonephritis and pyelonephritis, angiography and microangiography revealed corresponding findings.

Angiography↗
PubMed1990

[Application of an angiographic catheter with side holes to intra-arterial drug infusion--improvement of drug distribution by occlusion of the catheter tip].

To improve distribution of drug by intraarterial infusion a new catheter system with sideholes, tip of which was able to be occluded by an embolus, was developed. Inner diameter of the catheter was 0.038 inch. Tip of the catheter was so smoothly tapered to 0.025 inch in inner diameter that it could be occluded by an embolus of 0.038 inch in diameter. After occlusion of the tip, drug flowed out rectangly to catheter axis from only sideholes, resulting that drug flowed out was mixtured by blood stream to make a uniform distribution of it.

Catheterization↗