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K Kozima

Publications and source records attributed to K Kozima.

At least 19 recordsLinked to original sources
PubMed1996

Macrophagic cells outgrowth from normal rat glomerular culture: possible metaplastic change from podocytes.

One representative of a number of severe lesions that occur outside the glomerular capillaries and involve podocytes is crescentic glomerulonephritis. The question of whether the crescent-forming cells are derived from glomerular epithelial cells or monocytes/macrophages is highly controversial and has not yet been clarified. To investigate the pathophysiology of podocytes in crescentic glomerulonephritis, we attempted to establish methods for culturing cells confirmed to be derived from podocytes, focusing particularly on the relationship between podocytes and macrophages. Nonadherent cells of unknown origin that grew from normal rat isolated glomerular cultures increased in number, reaching a total of 3.5 x 10(5)/ml on Day 11. They showed several characteristics of macrophages, the expression of specific antigens and enzymes, morphology, and production of H2O2. They expressed Fx1A but lacked the expressions of Thy1.1 or factor VIII. A morphologic kinetic study on Days 3 to 11 of culture showed that the cells with foot processes on the glomerular basement membrane changed into macrophagic cells (MC) and migrated from the glomeruli. Immunofluorescence double staining indicated that the cells that migrated from the glomerular surface on Day 8 were both anti-podocalyxin- and ED-1-positive. Furthermore, immunoelectron microscopy revealed that the ED-1-positive cells were located on the glomerular basement membrane. Pretreatment with anti-macrophages and -Thy1.1 antibodies, both with complement, did not reduce the number of MC, whereas pretreatment with puromycin aminonucleoside predominantly reduced the number of MC. A predominant decrease in the number of glomerular macrophages by gamma-irradiation did not result in a reduction of the number of MC. MC derived from glomerular cultures of bone marrow chimeric rats expressed the la antigen originated from recipient, which indicates that MC is not derived from bone marrow cells. Macrophage colony-stimulating factor accelerated the speed of the change into MC, and granulocyte-macrophage colony-stimulating factor dramatically enhanced its degree with increase of cell number on Day 8. We concluded that podocytes change into MC in normal rat glomerular culture and that the change is enhanced by colony-stimulating factors. The results provide a completely new insight into the origin of crescent-forming cells.

Animals↗
PubMed1992

Stercoraceous perforation of the sigmoid colon: report of two cases.

Stercoraceous perforation of the sigmoid colon has rarely been reported in the literature. This lesion is assumed to be produced by the pressure from a hard scybalum resulting in a perforated ulcer with necrotic edges. Two cases of stercoraceous perforation of the sigmoid colon are presented in this paper. It is difficult to diagnose this lesion preoperatively, although ultrasonograms proved useful in showing the colon perforation. This lesion should always be suspected when a patient who has had chronic constipation presents with sudden severe abdominal pain. It is possible that this lesion is becoming more common as the mean age of the population increases and we stress the importance of immediate surgery and intensive care for improving the prognosis.

Aged↗
PubMed1991

[A case of intraosseous meningioma].

A case of intraosseous meningioma at the posterior fossa was reported. Intraosseous meningioma is very rate and only six cases have been reported in Japanese literature. A 64 year-old woman complained of progressive headache and was admitted to Ichinomiya Neurosurgical Hospital. On admission, neurological examination did not reveal any abnormalities. However, plain skull X-p showed a hyperostotic lesion in the right posterior fossa. CT scan demonstrated homogeneously enhanced mass by contrast medium. MRI showed a mass lesion of the posterior fossa on T1 and T2 weighted images. The right vertebral angiogram showed an avascular area in the right posterior fossa and no tumor stain. The tumor, which was partially attached to the underlying dura, was successfully removed surgically. The operative finding confirmed an intraosseous meningioma which had arisen from the right asterion. The post operative course was uneventful. Histological examination revealed fibroblastic meningioma.

Female↗
PubMed1985

Effects of a Fusobacterium nucleatum extract on immunoregulation in mice.

The purpose of this study was to examine the effect of an extract of Fusobacterium nucleatum on humoral and cell-mediated immunity and phagocyte functions in mice. The extract was obtained from the heat-inactivated supernatant of sonicated F. nucleatum. Mouse splenocytes were cultured with sheep red blood cells (SRBC), and antibody formation was assayed by counting the plaque-forming cells (PFC). After C3H mouse skin was grafted onto the BALB/c mouse, cytotoxicity of BALB/c mouse splenocytes to L-cells was enumerated, T- and B-cell blastogenesis was determined by the uptake of 3H-thymidine. In vivo phagocyte functions were measured using carbon clearance test, bactericidal, and acid phosphatase activity assays. The number of SRBC-specific and non-specific PFC in splenocytes stimulated with the extract increased 2.5-8.7-fold over that of unstimulated splenocytes. Cytotoxicity of splenocytes from the extract-injected mice decreased in a dose-dependent fashion at 12 days after grafting. T-cell mitogenicity of the extract was observed. The carbon clearance rate was reduced, and bactericidal and acid phosphatase activities were elevated by the extract injection of the mice. In conclusion, F. nucleatum extract has an adjuvant effect on humoral immunity, and a suppressive effect on cell-mediated immunity and activated phagocyte functions.

Animals↗
PubMed1984

Purification by sucrose density gradient zonal centrifugation and affinity column chromatography of antigenic substances from the livers of mice infected with Tyzzer's disease.

Antigenic substances from livers of mice infected with Tyzzer's disease were purified by means of sucrose density gradient zonal centrifugation and affinity column chromatography using antiserum and checking antigenicity with the complement fixation test. Fractions obtained from zonal centrifugation fell into three main groups with different molecular weights, two of which (Fr. I and Fr. II) positively reacted with antiserum in the complement fixation tests. Both fractions were further purified by affinity column chromatography. The molecular weights of the main antigenic substances derived from Fr. I and Fr. II were determined to be about 52 000 and 66 000, respectively, by means of SDS-PAGE.

Animals↗
PubMed1978

Dominant IgM deposition in experimentally induced amyloid kidney of the mouse and its immunological implications.

Prolonged hyperimmmunization of C3H mice with casein resulted in immune deposits in glomeruli which led to subsequent amyloid deposition. During the immunization, the animals were in state of extreme antigen excess without any detectable circulating antibodies. The immunofluorescent findings in the later period revealed predominant IgM deposition in glomeruli, which was quite consistent with the dominant presence of IgM antibody-forming cells in spleen in the apparently tolerant state.

Amyloid↗
PubMed1975

Experimental rheumatoid arthritis-like features induced by prolonged sensitization with focal antigens.

Prolonged sensitization with emulsion of an autologous or isologous subcutaneous abscess of Arthus type induced by injection of hen egg-white was performed in 34 rabbits which were divided into (high responder and intermediate responder groups (H- and M-groups) according to individual difference of immune responses. The development of a rheumatoid factor-like substance (RFLS) was demonstrated after 30 experimental days and subsequently observed in 21 out of 33 rabbits. There was no significant difference in the incidence of RFLS between both groups. As to the relation between the development of RFLS and types of focal antigens, the group of the autologous W-substance showed a higher incidence of RFLS than the N-substance. Acute and/or chronic synovitis was demonstrated in 13 of 33 rabbits and inflammatory changes were more intensive and extensive in the later period of experiment. Presence of RFLS in the affected synovial tissues, chiefly in the cytoplasm of plasma cells and mononuclear cells, occasionally in a free state was revealed by immunofluorescent study, and depositions positive for IgG and beta 1C were observed in the wall of blood vessels and fibrinous thrombi in the affected synovial tissues.

Animals↗
PubMed1968

Electron microscopic localization of the nephrotoxic antibody in the glomeruli of the rat after intravenous application of purified nephritogenic antibody-ferritin conjugates.

Nephritis in rats was induced by intravenous injection of purified ferritin-conjugated rabbit and duck nephrotoxic globulin. Using the fluorescent antibody technique, the same capillary pattern was found as that in glomeruli of rats receiving uncoupled nephrotoxic globulin. Electron microscopy revealed a heavy accumulation of the basement membrane-fixed antibody almost exclusively at the endothelial side. A higher concentration of ferritin was demonstrable in the peripheral basement membrane. The once-fixed antibody remained at the site of reaction though decreasing with time. The half-disappearance time seemed to be shorter than that of the uncoupled nephrotoxic globulin. No difference in localization was observed between rabbit and duck antibody. At least 40 basement membrane-fixed antibody molecules from the rabbit per 3000 mmicro(2) of filtration surface were needed to cause immediate nephritis. To induce nephritis using duck antibody, a greater number of basement membrane-fixed antibody seemed to be necessary. No evidence of specific reaction with constituents of glomerular cells was obtained.

Animals↗