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61.
In the present study, 13 cases of a peculiar gall-bladder granuloma characterized by marked proliferation of ceroid-fllled brown histiocytes were pathomorphologically, histochemically and ultrastructurally examined to define the pathologic features of such a lesion previously undescribed in the literature. The lesion grossly showed a granulomatous appearance of yellow brown to dark brown color developing in the wall of gall-bladder. Histologically, there was proliferation of histiocytes containing abundant brown pigment granules In their cytoplasm. The pigment granules proved to have staining characteristics closely resembling those of lipogenic ceroid-like pigment. Ultrastructurally, these granules showed membrane-bound, pleomorphic osmiophilic inclusions of heterogenous materials. With regard to the pathogenesis of this granuloma, it may be suggested that lipid components of bile juice, particularly unsaturated fatty acids and phospholipids, play an Important role as a source of ceroidogenesis In the proliferating histiocytes. 相似文献
62.
Junichi Tamaru Atsuo Mikata Makiko Itami Toshiyuki Takagi 《Pathology international》1990,40(7):517-521
Human non-Hodgkin's lymphomas were studied by means of an avidin biotin complex immunoperoxidase method using several monoclonal antibodies against the intermediate filament protein, vimentin. The study cases were 61 B cell lymphomas (including 2 plasmacytomas) and 30 T cell lymphomas (including 8 cases of mycosis fungoides). Twelve of the 61 B cell lymphomas were positive for vimentin, and were composed of extrafollicular center cells such as immunoblastic and plasmacytoid cells. On the other hand, lymphomas of follicular center cell origin were negative for vimentin. All cases of T cell lymphoma except for 14 (all of 9 AlLD- type lymphomas, all of 4 lymphoblastic lymphomas and one diffuse mixed small/ large lymphoma) were positive for vimentin. Although vimentin expression appeared to be influenced by various conditions such as the proportion of T- and B cell subsets, or B cell proliferation rate, follicular center cells were constantly negative for vimentin. 相似文献
63.
Postsynaptic potentials (PSPs) with long latencies were evoked in cat hindlimb motoneurons by stimulation of the distal stump of a cut ventral root. Measurements of their latency and the threshold in the responsible afferent fibers showed that they were produced mainly by the activity of the unmyelinated fibers in the ventral root that enter the spinal cord through the dorsal root. Patterns of PSPs evoked in flexor and extensor motoneurons by ventral root stimulation were similar to those observed in the flexion reflex. 相似文献
64.
Tarner IH Nakajima A Seroogy CM Ermann J Levicnik A Contag CH Fathman CG 《Clinical immunology (Orlando, Fla.)》2002,105(3):304-314
Rheumatoid arthritis (RA) is an autoimmune arthritis, for which treatment options remain limited. This study investigated the potential role of adoptive cellular gene therapy as a novel means for treating the RA animal model collagen-induced arthritis (CIA). Adoptive transfer of antigen-specific T-cell hybridomas retrovirally transduced to express IL-4 1 day before booster immunization significantly reduced the number of inflamed joints. Cell transfer after clinical onset of disease had no therapeutic effect. Bioluminescence imaging showed that the hybridomas migrated to the inflamed joints, thus delivering the regulatory protein locally at the site of inflammation. The homing was, at least in part, due to chemotaxis in response to proinflammatory chemokines that are expressed in inflamed joints. There were no significant changes in the cytokine milieu of the draining lymph nodes, nor in the systemic levels of anti-collagen antibodies in treated mice. We conclude that the beneficial clinical effects observed in our model were most likely based on the local action(s) of IL-4 in the inflamed joints and that the local delivery (and effects) of regulatory cytokines, like IL-4, constitutes a novel and effective method of preventing organ-specific autoimmune disease and of minimizing systemic adverse effects. 相似文献
65.
The effects of the 56-kilodalton protease (56K protease) from Serratia marcescens on complement-derived chemotactic activity were examined. Fresh human serum was incubated with zymosan to produce C5a. This activated serum was then incubated with various concentrations of 56K protease, and the chemotactic activity of mouse peritoneal exudate polymorphonuclear leukocytes (PMN) and macrophages was evaluated. A significant dose-dependent decrease of chemotactic activity was observed after protease treatment. Furthermore, treatment of human recombinant C5a with 56K protease at a dose of 1.0 microgram/ml resulted in a complete loss of chemotactic activity. When the living bacteria of the virulent strain, which produced about 10 times more protease than did the less virulent strain, were injected intraperitoneally into mice, the magnitude of infiltration of polymorphonuclear leukocytes into the peritoneal cavity was much lower than that caused by the less virulent strain. Because complement-dependent chemotactic activity is an initial response to bacterial infection, these results suggest indirect pathogenic functions of serratial proteases that suppress chemotactic activity. 相似文献
66.
Atsuo Ogura Toshihiko Asano Junichiro Matsuda Minako Koura Masaro Nakagawa Hiroshi Kawaguchi Yutaka Yamaguchi 《Virchows Archiv : an international journal of pathology》1990,417(3):223-228
Summary Glomerular lesions in hereditary nephrotic mice (ICGN strain) were investigated by electron microscopy. The glomeruli of unaffected animals, which appeared normal by light microscopy, had developed an ultrastructural change in the glomerular capillary basement membrane (GCBM). There was a partial thickening of the GCBM with bilaminar splitting of the lamina densa and an electron-dense fibrillar material exhibiting cross-striations. In affected animals, light microscopy revealed a marked thickening of GCBM and an increase of mesangial matrix without cellular proliferaton. By electron microscopy, multilaminar splitting of the lamina densa in the thickened GCBMs and fusion of the epithelial foot processes were observed. In some severely affected animals, immune complex deposition was found in GCBM, but little if any was observed in other animals. In the end, the glomeruli were globally sclerosed. Our findings suggest that initial structural abnormalities in GCBM may play an important role in the onset and development of the disease, though subsequent events such as immune complex deposition would modify the disease. 相似文献
67.
Junya Yoneda Ikuo Saiki Hideji Fujii Fuminori Abe Yutaka Kojima Ichiro Azuma 《Clinical & experimental metastasis》1992,10(1):49-59
We have investigated the effect of the immunomodulator ubenimex (hereafter referred to as bestatin) on the enzymatic degradation
of the extracellular matrix by human renal cell carcinoma SN12M cells during the invasive process. The invasion of SN12M cells
into reconstituted basement membrane (Matrigel) was inhibited by the presence of bestatin in a concentration-dependent manner.
However, bestatin did not have any effect on tumor cell adhesion and migration to the extracellular matrices which may be
involved in tumor cell invasion. Bestatin inhibited the degradation of type IV collagen by tumor cells, but not by tumor-conditioned
medium (TCM), in a concentration-dependent manner. We also found that bestatin inhibited hydrolysing activities towards substrates
of aminopeptidases in SN12M cells. Since bestatin was found to inhibit aminopeptidase activity, the inhibition of tumor invasion
by bestatin is likely to be associated with its action as an enzyme inhibitor. Bestatin only slightly inhibited tumor cell
plasmin activity, which can lead to the conversion of the latent collagenase to the active form, but this slight effect was
not significant. The zymography of TCM from SN12M cells showed that the treatment of tumor cells with bestatin resulted in
the disappearance of the 68 kDa type IV collagenase-enzyme level (active form) and slight reduction of the 72 kDa type IV
collagenase-enzyme level (latent form). These results indicated that bestatin may inhibit tumor cell invasion through a mechanism
involving its inhibitory action on aminopeptidases in tumor cells, suggesting that the aminopeptidase may partly be associated
with the conversion of a latent form of type IV procollagenase to an active form or the secretion of the collagenases from
tumor cells. 相似文献
68.
H Kanagawa E Takai F Tsuda A Machida M Kojima A Ishijima T Tanaka H Okamoto Y Miyakawa M Mayumi 《Journal of medical virology》1992,37(4):288-293
Of sera from 1,878 Japanese blood donors who carried hepatitis B surface antigen (HBsAg), 420 were subtyped as adw (22.4%) and 1,443 as adr (76.8%); only 15 (0.8%) contained HBsAg of subtype ayw or ayr. Sera with HBsAg/adr had higher HBsAg titres than those with HBsAg/adw (geometric mean of haemagglutination titre: 10.1 +/- 2.4 vs. 9.7 +/- 2.4, p less than 0.01), and a higher prevalence of hepatitis B e antigen (24% vs. 13%, p less than 0.001). Carriers of HBsAg/adr progressively predominated over those of HBsAg/adw with increasing age. Of sera from 1,863 carriers of HBsAg/adw or HBsAg/adr, 182 (9.8%) contained HBsAg particles with both subtypic determinants in the w/r allele. The presence of w and r determinants on the same particles was ascertained by sandwiching them between monoclonal antibody with the specificity for w and that with the specificity for r. HBsAg particles of compound subtype (adwr) were found more often in sera with hepatitis B e antigen than those without it (145/403 [36.0%] vs. 37/1,460 [2.5%], p less than 0.001). Sera with HBsAg/adwr particles had HBsAg titres higher than those without them (12.4 +/- 1.9 vs. 9.7 +/- 2.3, p less than 0.001). HBsAg/adwr particles arise from phenotypic mixing of the S-gene product of wild-type virus and that of mutants with point mutations for subtypic changes. The results obtained indicated that HBV strains of subtype adr have a higher replicative activity than those of adw, and suggested that mutations in the S gene for subtypic changes would be associated with an active replication of hepatitis B virus. 相似文献
69.
Hideo Sakuma Naoyoshi Mori Mizu Kojima Takeo Saito Fuminori Tachibana Makoto Naito 《Pathology international》1984,34(5):1157-1166
A case with lymphadenopathy of the left side of the neck in a 38-year-old male is described. He had a history of several relapses of about 10 years duration. Swollen lymph nodes were histologically similar to those of the hyaline-vascular type of Castleman's disease, but contained clear-cut lymph sinus and a sheet-like proliferation of plasma cells. Lymph follicles showed proliferation and atrophic germinal centers, in which cellular hypertrophy in the wall of ramifying small blood vessels, called angiosclerosis, was frequently encountered. During its progress, the patient developed plasmacytoma of the lymph nodes with varied clinical manifestations such as polyneuropathy, disturbance of gait, unusual perspiration, hirsuitism, gynecomastia, bilateral papilledema, and albumino-cytologic dissociation in cerebrospinal fluid. 相似文献
70.
Joji Haratake Atsuo Jimi Akio Horie Taizoh Inokuma Masato Ohno 《Pathology international》1984,34(4):925-933
This is a case report of a malignant mesenchymoma of the esophagus in a 50?year-old Japanese man. The tumor was a sessile polypoid mass showing a downward invasion limited to the submucosa of the esophagus. Histologically, the lesion contained rhabdomyosarcomatous and osteosarcomatous areas, in addition to an ill-defined fibrosarcomatous element. In contrast with reports of carcinosarcoma up to the present, this tumor lacked any invasive lesion of an epithelial malignancy. The morphogenesis of these tumor groups was discussed from a hamartoblastomatous standpoint. Acta pathol. jpn. 34: 925~933, 1984. 相似文献