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41.
We report a case of primary pulmonary low-grade marginal zone B-cell lymphoma of the mucosa-associated lymphoid tissue (MALT)-type with prominent sclerosis, which morphologically resembled pulmonary hyalinizing granuloma (PHG) or inflammatory pseudotumor (IPT) of the lung. The patient, a 66-year-old Japanese female with a history of Sj?gren's syndrome and primary biliary cirrhosis, presented with a lower left lobe mass 6.8 cm in diameter. Histologically, the lesion is characterized by dense bundles of collagen with scattered plasma cells, mature small lymphocytes, and histiocytes among the collagen bundles. Only the peripheral area of the nodule contained dense lymphoplasmacytoid and histiocytoid infiltrates. A few centrocyte-like cells were obscured by the numerous plasma cells and plasmacytoid cells. In addition, lymphoepithelial lesions and colonalized lymphoid follicles were identified by immunohistochemistry alone. Although PHG and IPT are unlikely to be confused with pulmonary MALT-type lymphomas, the present case suggests that MALT-type lymphoma should be added to the list of differential diagnoses for PHG and IPT.  相似文献   
42.
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   
43.
Recently genotyping of JC virus (JCV) DNA in renal tissue was reported to be useful to identify the geographic origin of unidentified cadavers. In the above study, autopsied tissue samples without storage or stored in a frozen state were used. This study examined JCV DNA sequence modifications caused by formalin-fixation, in an attempt to elucidate whether formalin-fixed, paraffin-embedded tissue samples can also be used to determine the genotypes of JCV DNA in the kidney. In four cases, a 610 bp typing region of the JCV genome was PCR-amplified from renal tissues stored for 1 year in three different states: frozen at -80 degrees C [Amaker, B.H., Chandler, F.W., Huey, L.O., Colwell, R.M., 1997. Molecular detection of JC virus in embalmed, formalin-fixed, paraffin-embedded brain tissue. J. Forensic Sci., 1157-1159], formalin-fixed, paraffin-embedded [Ault, G.S., Stoner, G.L., 1992. Two major types of JC virus defined in progressive multifocal leukoencephalopathy brain by early and late coding region DNA sequences. J. Gen. Virol. 73, 2669-2678], and soaked in 5% formalin [Baksh, F.K., Finkelstein, S.D., Swalskey, P.A., Stoner, G.L., Ryschkewitsch, C.F., Randhawa, P.R., 2001. Molecular genotyping of BK and JC virus in human polyomavirus-associated interstitial nephritis after renal transplantation. Am. J. Kidney Dis. 38 (2), 354-365]. The amplified fragments were cloned, and the resultant clones were sequenced. In frozen samples, single sequences ('original' sequences) were detected in all cases. In formalin-fixed, paraffin-embedded samples, not only the original sequences but also those with 1-6 base substitutions were detected. From formalin-soaked samples, the original sequences and those with 1-5 and 10-13 substitutions were detected. The genotyping of JCV DNA was not hampered by the presence of 1-6 substitutions, but a shift in JCV genotypes was observed in sequences with 10-13 substitutions. Thus, it was concluded that the genotypes of JCV DNA in the kidney can be determined only with specimens stored in a frozen state or formalin-fixed for a short time.  相似文献   
44.
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   
45.
A series of the copper(II) complexes of the type CuL4X2 (L: ligand, X: anion) was prepared with the following substituted imidazoles as ligands 2-ethyl- ( 1a ), 2-ethyl-4-methyl- ( 1b ), 2-phenyl- ( 1c ), 2-undecyl- ( 1d ), and 2-heptadecylimidazole ( 1e ). The structures of these complexes were confirmed by elemental analysis, reflection spectra of the crystals as well as IR-spectroscopy. Polymerization of acrylonitrile was tested in the presence of each imidazole-copper(II) complex in dimethyl sulfoxide solution.  相似文献   
46.
An autopsy case of systemic histiocytosis with excessive deposition of kappa-type light chain crystals was reported in a 58 year-old man who had consistently showed kappa-type light chain paraproteinemia, Bence Jones proteinuria and hypogammaglobulinemia for about 10 years until his death. However, no bony destruction was found by repeated X-ray examinations. At autopsy, extensive hyperplasia of crystal-storing histiocytes was observed in the bone marrow, spleen, liver, lymph nodes, interstitial tissues of visceral organs and loose connective tissues. In the bone marrow and some other tissues, mild proliferation of plasmocytoid cells containing small crystals were found. Histochemically the crystals positively stained with various methods for amino acids and proteins, especially with Weigerts' method for fibrin. Ultrastructurally intralysosomal crystal deposition was confirmed in the storage histiocytes and derivation of the crystals from Golgi's sacculi in the plasmocytoid cells was suggested. Biochemically the crystals were regarded as mainly consisting of dimers of a variable half of light chain immunoglobulin and immunochemically and immunohistochemically reacted to anti-kappa type light chain serum. Such a generalized storage histiocytosis may be secondarily induced by immunoglobulin synthesized in plasmocytoid cells.  相似文献   
47.
BACKGROUND: Chymase is a chymotrypsin-like serine protease primarily stored in mast cells. Infection with helminth parasites is known to increase the level of mast cell chymase in the jejunum and serum in mice. The aim of the present study is to elucidate the role of chymase in helminth infection. METHODS: Chymase inhibitor SUN-C8257 was administered to mice infected with the nematode Nippostrongylus brasiliensis, and the number of eosinophils in the blood, serum IgE levels and fecal egg counts were determined. RESULTS: Administration of SUN-C8257 significantly inhibited blood eosinophilia in BALB/c mice infected with N. brasiliensis. The effect of SUN-C8257 was specific for eosinophils, in that it affected neither the number of total leukocytes nor serum IgE levels. SUN-C8257 did not alter the fecal egg counts in this model, showing that SUN-C8257 has no effect on infectivity and expulsion of the nematode. N. brasiliensis infection induced eosinophilia in mast cell-deficient mice (W/W(v)) as well as their littermates (+/+), and SUN-C8257 inhibited the eosinophilia in +/+ mice but not in W/W(v) mice. These results suggest that the eosinophil number may be regulated by different mechanisms in W/W(v) and +/+ mice, and that the effect of SUN-C8257 on nematode-induced eosinophilia is probably due to chymase inhibition. CONCLUSIONS: Chymase released by activated mast cells may play a role in helminth-induced eosinophilia.  相似文献   
48.
While the pathological events evoked by infection are commonly described, effective host responses to bacteria and their products should primarily be protective. Heat shock protein (Hsp) expression is upregulated by many stimuli and serves to maintain intracellular protein integrity. The ability of the prototypic superantigen, Staphylococcus aureus enterotoxin B (SEB) to induce Hsps was investigated with BALB/c mice and by in vitro addition to the murine small intestinal epithelial cell line MSIE. SEB-treated (5 or 100 microg intraperitoneally) mice revealed increased Hsp25 and Hsp72, but not Hsc73, in jejunal lymphocytes and epithelial cells. A similar Hsp response to SEB occurred in MSIE cells and was preceded by activation of the ERK1/2 and p38 mitogen-activated protein kinases but not the SAPK/JNK pathway; pharmacological inhibition of ERK1/2, but not p38, significantly reduced SEB-induced Hsps. Moreover, SEB-treated MSIE cells were protected against oxidant-induced cytotoxicity (measured by 51Cr release) and F-actin depolymerization. Thus, SEB exposure results in a rapid induction of the Hsp25 and Hsp72 in intestinal epithelial cells, both directly and through lymphocyte activation, and we suggest that this event is important in protecting the gut from damage by Staphylococcus infection or in the reparatory process and may be a generalized response to lumen-derived bacterial toxins.  相似文献   
49.
The signal transduction pathways and activation of the MAP kinase or PI3 kinase signaling cascade regulate a variety of cellular processes, including proliferation and differentiation in hepatocytes. To elucidate the mechanisms of signal transmission required for the regulation of gap and tight junctions during DNA synthesis in rat hepatocytes, we determined changes of expression and function of gap and tight junctions of cells grown in primary culture, using inhibitors of signaling pathways for MAP kinase (PD98059) and PI3 kinase (LY294002). During the stimulation of DNA synthesis induced by epidermal growth factor (EGF), immunoreactivity and mRNAs of gap junction protein Cx32 and of tight junction protein claudin-1 markedly decreased with reduction of gap junctional intercellular communication (GJIC) and the fence function of tight junctions. In Western blots, whole-cell lysate of claudin-1 protein decreased and phosphorylated Cx32 protein in the insoluble fraction of Triton X-100 increased during the stimulation of DNA synthesis. During reinhibition of DNA synthesis, the changes of Cx32 and claudin-1 returned to control levels, as did both functions. In treatment with the inhibitors before DNA synthesis, PD98059 inhibited the changes of expression and function of Cx32, but not claudin-1, without inhibition of cell growth, whereas LY294002 completely inhibited cell growth. These findings indicate that the PI3 kinase pathway rather than the MAP kinase pathway plays an important role for EGF-induced proliferation of rat hepatocytes, and that changes of Cx32 in hepatocytes during the stimulation of DNA synthesis may be in part controlled through MAP kinase. Furthermore, Cx32, but not claudin-1, protein may be a target of activated MAP kinase in hepatocytes.  相似文献   
50.
Radiotherapy is one of the most effective treatments for cancers. However, external irradiation provides only small doses to deep-seated cancers, and often causes damage to healthy tissues. It has been reported that 20-30 microm diameter 17Y(2)O(3)-19Al(2)O(3)-64SiO(2) (mol%) glass microspheres are useful for the in situ irradiation of cancers. Yttrium-89 (89Y) in this glass can be neutron bombarded to form the beta-emitter 90Y (half-life=64.1h). When injected in the vicinity of the cancer, such activated glass microspheres can provide a large localized dose of beta-radiation. The Y(2)O(3) content of the glass in the microspheres is limited to only 17 mol%. Chemically durable microspheres with a higher Y(2)O(3) content need to be developed. Phosphorus-31 (31P) with 100% natural abundance can also be activated by neutron bombardment to form the beta-emitter 32P (half-life=14.3d). Chemically durable microspheres containing a high phosphorus content are expected to be more effective for cancer treatment. We prepared pure Y(2)O(3) and YPO(4) microspheres using a high-frequency induction thermal plasma melting technique, and investigated the resulting structure and chemical durability. We successfully prepared smooth, highly spherical polycrystalline Y(2)O(3) and YPO(4) microspheres with diameters in the range 20-30 microm. Both the Y(2)O(3) and YPO(4) microspheres showed high chemical durability in saline solutions buffered at pH=6 and 7. These microspheres are expected to be more effective than the conventional glass microspheres for the in situ radiotherapy of cancer.  相似文献   
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