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101.
102.
103.
Intensified IgA mesangial deposits after administration of sheep anti-type IV collagen serum in mice
Sheep anti-type IV collagen serum was intravenously administered to male mice of the BALB/c, C3H and ddY strains, and their kidneys were morphologically studied monthly for 10 months thereafter. By immunofluorescence, the sheep IgG was seen to have immediately become conjugated to the glomeruli, mainly in a mesangial pattern. Successively, autologous mouse C3 and IgG appeared with the same type of distribution. Within 3 to 4 months after the start of the experiment, mouse IgA also appeared in the mesangium, especially in ddY mice. The intensity and frequency of mesangial IgA deposition and the serum IgA level increased with time in this strain. BALB/c and C3H mice also showed the same tendency of mesangial IgA deposition, although to a lesser degree. In summary, it was concluded that mesangial IgA deposition was due to non-immunological local trapping, on the basis of the results obtained by ELISA analysis of the sera and renal eluate. Although the ddY mouse is known to show spontaneous mesangial IgA deposition associated with a high serum IgA level with aging, these characteristics were much accelerated and intensified by this antiserum treatment. The relation of this observation to the pathogenesis of human IgA nephritis is discussed. 相似文献
104.
Keiji Nagai Yukihiko Ueno Nobuo Takamiya Masao Kaneko 《Macromolecular chemistry and physics.》1995,196(4):1241-1250
The photoluminescent Ru(bpy) complex was dispersed in a polysiloxane film containing 2,2′-bipyridine (bpy) pendant groups. The unusually long photoluminescence lifetime of the Ru(bpy) (1,94 μs at 25°C) and the blue-shifted photoluminescent wavelength suggest a rigid polymer matrix. The fluorescence yield becomes lower with higher probe concentration, indicating concentration quenching. According to the analysis based on Stern-Volmer plots, the quenching obeys a mechanism composed of both static and dynamic processes. A statistical intermolecular distance distribution between the probes was used to interpret the results in terms of static and dynamic quenching. It is shown that in the present system the dispersed complexes diffuse slightly during the excited state. 相似文献
105.
Phenotypic and functional heterogeneity of endothelial cells (ECs) is being recognized with increasing frequency. Here we report a novel murine monoclonal antibody (MoAb), named 8C9, that detects a unique epitope on the leukocyte differentiation antigen CD36 (platelet glycoprotein IV or IIIb) expressed by both normal and neoplastic ECs. In immunohistochemical and flow-cytometric studies, 8C9-immunoreactivity was detected on capillary ECs, adipocytes, monocytes, platelets and a human monocytoid cell line U-937, which are known to express the CD36 antigen. Blocking experiments using U-937 cells and studies on cryostat sections revealed that a murine MoAb OKM5, which detects the CD36 antigen, blocked the binding of 8C9 to its antigen. Immunoblot analysis showed that 8C9 bound to a 97-kDa membrane protein expressed by U-937 cells treated with phorbol ester. These results indicate that 8C9 detects the CD36 antigen. However, the findings that some OKM5-positive normal ECs in the liver, spleen and lymph nodes as well as neoplastic ECs in a cutaneous angiosarcoma did not react with 8C9, together with the fact that the CD36 antigen does not form a complex or associate with other proteins, suggest epitopic heterogeneity of the CD36 antigen expressed by these tissues. 相似文献
106.
Nakamichi I Takakuwa T Tanio Y Iuchi K Aozasa K 《Virchows Archiv : an international journal of pathology》2005,447(5):888-891
Pyothorax-associated lymphoma (PAL) is a B-cell lymphoma which develops in the pleural cavity of patients with an over-20-year
history of pyothorax. Aberrant expression of surface antigens is occassional in PAL, although genotype is not fully investigated.
We report here a PAL with dual genotype, i.e., simultaneous immunoglobin (Ig) and T-cell receptor (TcR) gene rearrangement.
An 82-year-old woman with pain on the left side of the chest was admitted. She had been suffering from pyothorax after artificial
pneumothorax for treatment of tuberculosis of the pulmonary when she was 18 years old. The mass that was confined to the left
pleural cavity affected by pyothorax was biopsied and histologically diagnosed as diffuse large cell lymphoma. The tumor cells
were positive for CD20, CD16, and TIA-1 but negative for CD79a, CD45RO, CD43, CD3, and CD56. Surface antigen expression was
further investigated in cultured cells, showing that the cultured cells did not express representative B-cell markers, except
for CD20, as well as T-cell markers, but were positive for CD16, CD30, and CD103. Southern blotting revealed the monoclonally
rearranged bands of both Ig heavy chain and TcR gene. The patients died of tumors 14 months after admission. Aberrant genotype
and immunophenotype of PAL cells is discussed in reviewing the pertinent literature. 相似文献
107.
The organization of serotonin fibers in the anterior column of the mammalian spinal cord. An immunohistochemical study 总被引:1,自引:0,他引:1
Detailed comparative analysis of the organization of serotonin fibers in the anterior column of the mammalian spinal cord (rat, guinea pig, cat, dog and monkey) was carried out by use of the indirect antibody peroxidase-antiperoxidase (PAP) method. The plexus formation of serotonin-containing varicose fibers around the alpha-motoneurons in the monkey anterior horn was in much closer apposition to the cell bodies in comparison with the spinal cords of the rodents and carnivores. The results may suggest that anterior horn motoneurons in the simian spinal cord are intimately innervated by serotonin fibers in a manner different from that of rodents and carnivores. Furthermore, the small cell groups endowed with particularly dense networks of serotonin fibers were demonstrable in the anterior horn of L1-L2 segments of rats, and L3-L4 of guinea pigs and monkeys; however, in the lumbar levels of the carnivores this was not the case. Hence it seems doubtless that there exists in the lumbar anterior horn of the rodent and primate spinal cords a cell group with an unknown specialized function. 相似文献
108.
Green tea and gastric cancer 总被引:2,自引:0,他引:2
109.
A case of neurofibroma of the gallbladder in a 44-year-old woman without von Recklinghausen neurofibromatosis but with right hypochondralgia is reported. The tumor was seen preoperatively as a polypoid lesion and in the resected gallbladder as a papillary polypoid growth over the main intramural tumor mass. Microscopically, the tumor was identified as a neurofibroma with many tactile corpuscle-like structures (Wagner-Meissner bodies), which were found by electron microscopic and immunohistochemical examination to consist of Schwann cells. Twelve cases of non-epithelial neoplasms arising in the gallbladder are also reviewed. 相似文献
110.
Sano C Sato K Shimizu T Kajitani H Kawauchi H Tomioka H 《Clinical and experimental immunology》1999,115(3):435-442
We assessed the roles of proinflammatory cytokines IFN-gamma and TNF-alpha, and immunoregulatory cytokines IL-10 and TGF-beta in the modulation of the anti-microbial activity of murine peritoneal macrophages against Mycobacterium avium-intracellulare complex (MAIC). First, both IFN-gamma and TNF-alpha significantly reduced the bacterial growth in macrophages, indicating that these cytokines participate in up-regulation of macrophage anti-MAIC function. Second, although MAIC-infected macrophages produced substantial amounts of IL-10 and TGF-beta, neutralization of endogenous IL-10 and TGF-beta with anti-IL-10 and anti-TGF-beta antibodies, respectively, did not affect the intracellular growth of MAIC in macrophages from mice with BcgS (MAIC-susceptible) or BcgI (MAIC-resistant) genotype, regardless of the virulence of test MAIC strains. The same result was also obtained for macrophages stimulated with IFN-gamma or TNF-alpha. Third, in MAIC-infected mice, the growth of organisms at the sites of infection (lungs and spleens) was not affected by administration of anti-IL-10 or anti-TGF-beta antibodies. These findings indicate that, in the case of mice, endogenous IL-10 and TGF-beta are essentially ineffective in down-regulating macrophage anti-MAIC functions not only in vitro but also in vivo. 相似文献