Search PubMed⌕ Search

Biomedical subjects

T Kusunoki

Publications and source records attributed to T Kusunoki.

At least 55 records · Page 3Linked to original sources
PubMed1994

Involvement of CD11b/CD18 in enhanced neutrophil adhesion by Fc gamma receptor stimulation.

Neutrophils showed a rapid and transient adhesion to immunoglobulin G (IgG)-coated plates compared with their adhesion to bovine serum albumin (BSA)-coated plates: the adhesion reached a peak after 15 min of incubation and then gradually returned to almost the basal state in 60 min. The addition of monomeric IgG or anti-Fc gamma RII monoclonal antibody (mAb) (IV.3) suppressed the increase in adhesion, whereas anti-Fc gamma RIII mAb (3G8) was hardly effective, indicating that the interaction of Fc gamma R, especially Fc gamma RII, with coated IgG is involved in the process. Adhesion was also blocked by cytochalasin B, suggesting that functional actin filament structures are crucial. Protein kinase inhibitors, erbstatin and genistein, inhibited the adhesion in a dose-dependent manner. The adhesion was inhibited by anti-CD11b (M1/70) and anti-CD18 (MHM23, TS1/18) mAbs. Moreover, neutrophils from a patient with complete leukocyte adhesion deficiency syndrome did not show increased adhesion to IgG-coated plates. The adhesion of neutrophils to fibrinogen- and BSA-coated plates was also increased when Fc gamma R was stimulated in the fluid phase with soluble aggregated IgG, which was also inhibited by anti-CD11b mAb. Stimulation of neutrophil Fc gamma R with soluble aggregated IgG enhanced the expression of CD11b in concert with the enhanced adhesion. These data collectively suggest that stimulation via Fc gamma R evokes a tyrosine kinase-dependent and actin filament-dependent intracellular signal that enhances the specific and nonspecific adhesive activity of neutrophils, presumably through the activation of CD11b/CD18.

Adult↗
PubMed1994

[Histopathological findings of human thyroid tumors and signal intensities of magnetic resonance imaging (MRI)].

We studied the correlation between postoperative thyroid histological findings and signal intensities of preoperative magnetic resonance (MR) imaging. The study subjects included 20 cases with thyroid diseases (7 with adenomatous goiter, 2 with follicular adenoma, 6 with papillary carcinoma, 5 with follicular carcinoma). Solid diseases excluding secondary changes (calcification, hemorrhage, necrosis and fibrosis) were investigated by T1 weighted imaging (T1WI) and T2 weighted imaging (T2WI). The results of this study showed that high signal intensities on T1 and T2 indicated preserved follicular structures with a full colloid and sparse atypical cells, in both benign and malignant diseases. Trabecular and microfollicular structures that showed destruction of follicular components and sparse colloid, had a tendency to show low approximately iso signal intensities on T1WI imaging. These results suggest that differentiated grades and the cell proliferative ability of thyroid tumors may be predictable with a combination of T1WI and T2WI.

Adult↗
PubMed1993

Organization of the cerebral ganglion of the colonial ascidian Polyandrocarpa misakiensis.

The cerebral ganglion of a budding styelid ascidian, Polyandrocarpa misakiensis, whose phylogenetic location is midway between vertebrates and invertebrates, was studied by light and electron microscopy to obtain some insight into the evolution of the central nervous system. The lateral and ventral sides of the ganglion are surrounded by blood sinuses. The ganglion is covered with a thin fibrous sheath through which many nerve fibers run. The ganglion is composed of a cellular cortex and a fibrous medulla. The cortex consists of three to six layers of large and small neurons. Some neurons are also scattered within the medulla. Many neurons are monopolar, and some are bi- or multipolar. The cytoplasm of the large neurons is dense with extensive rough endoplasmic reticulum, free ribosomes, mitochondria, one or more Golgi complexes, large dense bodies, and many clear or dense vesicular structures. Some neurons send their processes directly into the lumen of the sinuses. The medulla is composed of loosely arranged nerve fibers without cellular wrappings. The medullary fibers contain vesicles and granules of various sizes, and microtubules. At the anterior and posterior ends of the ganglion, the medullary fibers are assembled into thick peripheral nerve fiber bundles. The peripheral nerve fibers are enveloped and subdivided by fibrous structures. Synapses are found in the medulla, in the cortex, and between the peripheral nerve fibers. The presence of neurons and axodendritic or axoaxonic synapses in the peripheral nerve fibers is consistent with a diffuse organization of the central nervous system of the ascidians. The morphology of the central nervous system synapses is comparable to that of other invertebrates, but the locations of the synapses are similar to those of vertebrates.

Animals↗
PubMed1993

Giant terminals in the dorsal octavolateralis nucleus of lampreys.

The dorsal octavolateralis nucleus of lampreys is a primary nucleus for electroreceptive stimuli in the medulla. In Lampetra japonica, the rostral and caudal thirds of this nucleus are exclusively occupied by giant terminals, which become evident when the primary fibers of an electrosensory nerve (recurrent branch of the anterior lateral line nerve) are labeled with horseradish peroxidase. We studied the ultrastructure of these terminals. They contain neurofilaments, mitochondria, microtubules, and tubular membranous structures. Many synapses, all of the chemical type, are located around the neck region of the terminal swellings. Many vesicular structures, which are clear, round, and uniform in size, and most of which are probably synaptic vesicles, are densely clustered in a single large mass in the neck region of the terminals. Some of the tubular structures may serve as a membrane reservoir for the large number of synaptic vesicles required in the giant terminals.

Animals↗
PubMed1993

Manganese superoxide dismutase content and localization in human thyroid tumours.

Manganese-containing superoxide dismutase (Mn-SOD) content and its immunohistochemical localization in human thyroid tumours and some other thyroid diseases were examined and compared with adjacent normal thyroid tissue. Enzyme-linked immunosorbent assay (ELISA) was used in this study for the measurement of Mn-SOD. The content of Mn-SOD tended to increase in diffuse hyperplasia, adenomatous goitre, and follicular adenoma. In papillary carcinoma, it was significantly higher than in adjacent normal thyroid tissue. Follicular carcinoma also revealed a markedly high Mn-SOD content. In the immunohistochemical study, adjacent normal thyroid tissue showed granular positive staining of Mn-SOD in the cytoplasm. An increase of Mn-SOD was observed in the papillary proliferative lesion of diffuse hyperplasia and in the follicles adjacent to lymphoid tissue in chronic thyroiditis with hypothyroidism. Strong positive staining of Mn-SOD was observed in papillary and follicular carcinomas, whereas in anaplastic carcinoma staining was markedly less intense. These results indicate that the Mn-SOD content varies according to the degree of differentiation of thyroid carcinomas.

Adenoma↗
PubMed1993

[Study on human diseased thyroid cells in collagen gel culture--morphology and their malignancy of cultured colonies].

Thyroid cells from 14 normal subjects, two patients with Grave's disease, four patients with follicular adenoma and eight patients with papillary carcinoma were cultured in collagen gel. The colonies of these cells were stereoscopically observed and their morphological characteristics were studied with regard to relation with pathological findings of mother tumor, extra-capsular invasion and metastatic potential. For normal thyroid, Grave's disease and follicular adenoma (except for one case), their own characteristic branching type colonies were found. For papillary carcinoma, both branching type and spheroid type of colonies were observed. The ratio of branching type/spheroid type varied individually in the patients with papillary carcinoma. However, the spheroid type was found to trend to be predominant in patients with extra-capsular invasion and/or lymph node metastasis. This means that the observation of spheroid type colonies in collagen gel is suggestive of risk of extra-capsular invasion or lymph node metastasis. From the obtained results, it seemed possible to diagnose poorly-differentiated cells in vitro by morphologically observing colonies of human thyroid papillary carcinoma cells developing in collagen gel.

Adenoma↗
PubMed1993

[Proliferating cell nuclear antigen (PCNA) on human diseased thyroid cells].

Surgical materials obtained from 5 normal human thyroids and 19 diseased tissues (4 with Grave's disease, 4 adenomatous goiters, 3 follicular adenomas, 2 papillary carcinomas, 4 follicular carcinomas and 2 undifferentiated carcinomas) were investigated immunohistochemically using the avidin-biotin-peroxidase complex technique with anti-proliferating cell nuclear antigen (PCNA) antibody and epidermal growth factor receptor (EGFR) antibody. The results of this study suggested the following: (1) Labeling indexes of PCNA positive cell nuclei were shown in high grade malignant cases accompanied by capsular invasion and lymph node metastasis, in undifferentiated carcinoma cells, and in proliferative lesions of benign diseases. These results suggest that PCNA is indicative of proliferative ability in thyroid diseases. (2) On thyroid tumors, EGFR regions with strong positive staining showed many PCNA positive cell nuclei. EGF appears to have a significant association with proliferative ability in thyroid diseases.

Adult↗
PubMed1993

Scintigraphic evaluation of gastroesophageal reflux following gastrectomy.

We used scintigraphy to detect and quantify gastro-esophageal reflux, and determined the sensitivity of this method for identifying patients with clinical symptoms and/or endoscopic evidence of reflux. Thirty gastrectomy patients with heartburn and regurgitation, and 8 healthy controls were studied. The gastro-esophageal reflux index, calculated from imaging data, correlated significantly with the symptom score of the subjects, and the index was significantly larger in the symptomatic patients group (7.07 +/- 1.21) than in the healthy control group (1.54 +/- 0.22) (p < 0.001). Our study suggests that scintiscanning is capable of detecting gastro-esophageal reflux accurately, rapidly, noninvasively, and with a high degree of sensitivity. In addition, scintiscanning can be employed to quantify reflux in gastrectomy patients.

Adult↗
PubMed1993

Gastroesophageal scintigraphy following gastrectomy: comparison to endoscopy and esophageal biopsy.

We evaluated the relationship between gastroesophageal scintigraphy, endoscopy, and biopsy in 48 gastrectomy patients (33 with reflux and 15 without reflux symptoms). Endoscopic esophagitis was demonstrated in 78.8% of the patients with reflux symptoms, histological esophagitis was found in 72.2% of them, and scintigraphic reflux was found in 81.8%. Either endoscopic or histological esophagitis was recognized in 93.7% of the patients with reflux symptoms, while either scintigraphic reflux or endoscopic esophagitis was demonstrated in 97.0%. Scintigraphic reflux was significantly more common in patients with histological esophagitis than in those without it (92.9% vs. 40%, p < 0.01). In addition, it was found in 74.2% of patients with and 64.7% of patients without endoscopic esophagitis. The reflux index tended to increase as the grades of esophagitis increased; there was an approximate relationship between the two parameters. Our study suggested that scintigraphy reflects histological esophagitis rather than endoscopic esophagitis, and that there was an approximate relationship between the reflux index and the endoscopic grade of esophagitis. In addition, performance of scintigraphy and endoscopy combined with esophageal biopsy increased the diagnostic yield in gastrectomy patients with reflux symptoms.

Biopsy↗
PubMed1993

Monomeric IgG2 enhances Ig production and proliferation in human B cells.

The effect of purified polyclonal human IgG subclasses on B-cell responses was studied using the human IgA-producing B-cell line GM-1056. IgG2 at concentrations of 0.01-1 microgram/mL enhanced both IgA production and proliferation, while IgG1, IgG3, and IgG4 each failed to do so at tested concentrations between 0.001 and 10 micrograms/mL. This enhancement was Fc gamma R mediated, since IgG2 Fc fragments enhanced IgA production and proliferation to the same extent as did the whole IgG2 molecule, whereas F(ab')2 fragments did not. However, in contrast to monomeric IgG2, aggregated IgG2, which was expected to bind Fc gamma RII on B cells, affected neither IgA production nor proliferation. Similarly, anti-CDw32 mAb (2E1, anti-Fc gamma RII), anti-CD 64 mAb (32.2 anti-Fc gamma RI), and anti-CD16 mAb (Leu 11a, anti-Fc gamma RIII) mAb each failed to stimulate GM-1056 cells, and more importantly did not block IgG2-induced stimulation. Of various cytokines tested, including IFN-alpha, IFN-gamma, IL-1 beta, IL-2, IL-3, IL-4, IL-5, and IL-6, IL-6 alone augmented IgG2-induced enhancement of IgA production and proliferation. Moreover, the IL-6 effect was lost following preabsorption with anti-IL-6 antibody but not following preabsorption with control antibody. IgG2 also enhanced Ig production and proliferation in tonsillar large activated B cells, while IgG1, IgG3 and IgG4 each failed to do so. In contrast, IgG2 had no effect on Ig production and proliferation in tonsillar small resting B cells or SAC-stimulated small B cells. IgG2-induced enhancement of Ig production and proliferation in large B cells was not blocked by 2E1, 32.2, or Leu 11a, while enhancement was augmented in a specific fashion by IL-6. These results indicate that monomeric IgG2 specifically enhances B cell responses via an Fc gamma R receptor distinct from Fc gamma RI, Fc gamma RII, and Fc gamma RIII, and that IL-6 may play a role in augmenting this response.

B-Lymphocytes↗
PubMed1993

Morphological properties of human thyroid tumor cells in collagen gel culture and metastatic or invasive ability.

Using normal human thyroid cells and tumor cells, the reconstruction of various diseased cells in collagen gel as well as the relationship between the morphology of colonies in collagen-embedded culture and the biological behavior (benignity, malignancy, metastasis, and invasion) of the original tumors were studied. In collagen gel culture, normal thyroid cells reorganized follicle-like constructions, and follicular adenoma cells showed in vivo-like constructions. However, two different types of colonies were observed in cultures of cells from papillary carcinomas. One was the branching type with many outgrowths projecting to three dimensions and the other was the spherical type without any outgrowths. These spherical colonies were observed in all cases of papillary carcinoma, but varied from one case to another. Metastasis and invasion were detected during pathological examination in cases with a high ratio of spherical colonies. Our results indicate that cells from highly metastatic and invasive thyroid cancer form spherical colonies in the collagen gel culture, and that this collagen culture is a useful method for studying the heterogeneity of tumor cells as well as the metastasis and invasive ability of tumor cells in vitro.

Adenoma↗
PubMed1992

Tyrosine phosphorylation and its possible role in superoxide production by human neutrophils stimulated with FMLP and IgG.

Superoxide production by human neutrophils stimulated with FMLP and soluble aggregated human IgG were inhibited in a dose dependent manner by two kinds of tyrosine kinase inhibitors, erbstatin and genistein. Superoxide production stimulated with surface bound IgG, however, was scarcely inhibited by either inhibitor. Protein tyrosine phosphorylation studies with immunoblotting revealed specific tyrosine phosphorylation of a 40 Kd protein by soluble aggregated and surface bound IgG, and that of a 39 Kd protein, as well as the 40 Kd protein, by FMLP. These were all inhibited by the tyrosine kinase inhibitors. These data suggest that superoxide production induced by FMLP and soluble aggregated IgG are, at least in part, tyrosine kinase dependent, but the tyrosine kinases and/or substrates of tyrosine kinases involved may be different. In addition, tyrosine kinase independent pathways are also suggested to be involved in superoxide production by stimulation with surface bound IgG.

Humans↗
PubMed1991

Complete primary structure of a galactose-specific lectin from the venom of the rattlesnake Crotalus atrox. Homologies with Ca2(+)-dependent-type lectins.

The complete primary structure of a galactose-specific lectin contained in the venom of the rattlesnake, Crotalus atrox, was determined. The lectin is composed of two covalently linked, identical subunits, each consisting of 135 amino acid residues. Under physiological conditions the lectin proved to be highly aggregated. The venom lectin contained 9 half-cystines, 8 of which formed four intrasubunit disulfide bridges (Cys3-Cys14, Cys31-Cys131, Cys38-Cys133, and Cys106-Cys123), while Cys86 was involved in an intersubunit disulfide bridge. Because of the high content of disulfide bridges, the intact lectin was extremely resistant to tryptic digestion. The determined amino acid sequence was found to be homologous with those of the so-called carbohydrate recognition domains of Ca2(+)-dependent-type lectins in animal. Among them, 8 amino acid residues (Cys31, Gly69, Trp92, Pro97, Cys106, Asp120, Cys123, and Cys131) were completely conserved. Leu40, Trp67, and Trp81 were also well conserved. The rattlesnake venom lectin showed high hemagglutinating activity. These results, together with the occurrence of similar lectins in crotalid venoms, suggest that these lectins have evolved in order to make the venom a more effective weapon to capture prey animals.

Amino Acid Sequence↗
PubMed1991

Intercellular IgA dermatosis of childhood. Selective deposition of monomer IgA1 in the intercellular space of the epidermis.

We describe a 7-year-old girl with recurrent pruritic vesiculopustular lesions involving the trunk, extremities, face, and oral mucosa. Histopathologic examination revealed intraepidermal bullae containing neutrophils and eosinophils, and direct immunofluorescence test showed the deposition of IgA in the intercellular space of the epidermis. Circulating IgA anti-intercellular antibodies were also detected by indirect immunofluorescence test. Immunofluorescence studies using monoclonal antibodies to human IgA subclasses showed that these IgA antibodies belonged to IgA1. Antisera against J chain and secretory component did not show any specific intercellular staining. Surface IgA(+)-B cells were transiently increased in the peripheral blood during the active stage of the disease. These results indicated the extragut origin of these IgA antibodies. Dapsone therapy was shown to be very effective.

Child↗
PubMed1991

Nerve growth factor specifically induces human IgG4 production.

The effect of nerve growth factor (NGF) on human IgG4 production was studied. NGF specifically enhanced IgG4 production in cultures of human tonsillar mononuclear cells without affecting production of other isotypes or other IgG subclasses. Optimal enhancement of IgG4 production by NGF required the presence of T cells. However, NGF induced significant IgG4 production by small resting B cells in the absence of T cells, and this production was enhanced by stimulation with Staphylococcus aureus Cowan strain I (SAC). In contrast to small B cells, large activated B cells produced IgG4 spontaneously; this production was enhanced by NGF. NGF also enhanced IgM and IgA production by large B cells, while production of IgG1, IgG2, IgG3 and IgE was not affected. The enhancement of IgG4 production was blocked by anti-NGF serum but not by control serum. NGF, T cells and SAC, separately or together, failed to induce IgG4 production by surface (sIgG4+)-depleted B cells. In contrast to NGF, other recombinant human cytokines including interleukin (IL) 1 beta, IL 2, IL 4, IL 5, IL 6, granulocyte-macrophage colony-stimulating factor, interferon alpha and gamma failed to induce IgG4 production. These results suggest that NGF directly and preferentially stimulates activated sIgG4+ B cells to produce IgG4.

B-Lymphocytes↗
PubMed1991

Application of mathematical model to multiple-dose experimental chemotherapy for fatal murine pneumonia.

Two beta-lactam antibiotics, cefazolin and cefmenoxime, were administered for 7 days to mice with pneumonia caused by Klebsiella pneumoniae by using dosage regimens that would simulate multiple dosing in usual clinical treatments at dosing intervals of 8 or 12 h. Viable numbers of the bacteria in the lungs were measured at 12- or 24-h intervals. The mathematical model established in a previous single-dose study was applied in this study to explain the time courses of the changes in bacterial count over 7 days. However, because the error in viable count measurements was larger than that in the previous study, the time course of the changes in mean viable count was not regular and the viable count reduction rate changed during multiple dosing, and therefore it was difficult to explain the time course by repeated application of the mathematical model described previously. This study suggests that the changes in pharmacokinetic and pharmacodynamic parameters during multiple dosing need to be considered.

Animals↗