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51.
An autopsy case of systemic histiocytosis with excessive deposition of K-type light chain crystals was reported in a 58 year-old man who had consistently showed K-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 Ultra-structurally 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- type light chain serum. Such a generalized storage histiocytosis may be secondarily induced by immunoglobulin synthesized in plasmocytoid cells.  相似文献   
52.
We report here that loss of the Sprouty2 gene (also known as Spry2) in mice resulted in enteric nerve hyperplasia, which led to esophageal achalasia and intestinal pseudo-obstruction. Glial cell line-derived neurotrophic factor (GDNF) induced hyperactivation of ERK and Akt in enteric nerve cells. Anti-GDNF antibody administration corrected nerve hyperplasia in Sprouty2-deficient mice. We show Sprouty2 to be a negative regulator of GDNF for the neonatal development or survival of enteric nerve cells.  相似文献   
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We describe the case of a 40-year-old man whose disease was initially diagnosed as acute myelocytic leukemia. The patient achieved remission with chemotherapy, but relapsed shortly afterwards with an acute T-cell lymphoblastic leukemia. He died of intracranial bleeding. Karyotyping analysis showed a del(9p?) as a common abnormality in the leukemic cells at onset and relapse. Fluorescence in situ hybridization analysis demonstrated allelic loss of the CDKN2A gene in cells from both stages of the disease. At relapse the leukemia cells had additional abnormalities such as add(1)(p36) and del(12)(p11). We postulate that the loss of CDKN2A is involved in leukemogenesis but does not determine the lineage of the leukemic cells. Instead, abnormalities of genes at 1p36, 12p11, or both may be involved in driving a lymphoid phenotype.  相似文献   
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MRL-lpr/lpr (MRL/lpr) mice spontaneously develop arthritis by an increase in the incidence of agalactosylated oligosaccharides in serum IgG, similar to rheumatoid arthritis patients. However, whether this association has a pathogenic significance is still unknown. In this study, we analyzed the oligosaccharide structure of serum IgG in various MRL mice with or without arthritis, to clarify the relationship between the oligosaccharide abnormality and the development of arthritis. The level of agalactosylation in serum IgG was comparable in both arthritis-free MRL/lpr and MRL-+/+ (MRL/+) mice at 6 weeks of age. In contrast, the incidence of IgG lacking galactose markedly increased in MRL/lpr mice at 6 months of age (the age at which arthritis occurred), compared with that from age-matched MRL/+ mice without arthritis. However, the proportion of agalactosylated IgG increased similarly in anti-CD4 monoclonal antibody-treated MRL/lpr mice at 6 months of age, despite the absence of the development of arthritis, because of depletion of CD4+ T cells. These results suggest that the abnormality in IgG galactosylation of MRL/lpr mice developed in an age-dependent manner, but it did so independently of CD4+ T cell-dependent B-cell activation and is not a consequence of the development of arthritis.  相似文献   
57.
We have found that the pleural effusion obtained from a patient with lung cancer (adenocarcinoma) has cytotoxic activity against the patient's lung cancer cells. This finding occurred in the course of establishing a lung cancer cell line from the patient's pleural effusion. The cytotoxic factor was partially purified from the pleural effusion and characterized. It had cytotoxicity against L-929 mouse fibroblasts in the standard 18-h killing assay of tumour necrosis factor (TNF). By molecular sieving chromatography, the activity appeared at molecular weight of 50,000. This activity was completely blocked by a monoclonal antibody to TNF. From these results, we conclude that the cytotoxic factor in the pleural effusion is TNF. The concentration of TNF in the pleural effusion was 34.5 pg/ml by radioimmunoassay. In addition, we detected TNF activity and protein in two other cases of carcinomatous pleural effusion. Therefore, it would appear that in vivo TNF displays cytotoxic activity against cancer cells.  相似文献   
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59.
Trypanosome alternative oxidase (TAO) is the terminal oxidase of the respiratory chain of long slender bloodstream forms (LS forms) of African trypanosoma, which causes sleeping sickness in human and nagana in cattle. TAO is a cytochrome-independent, cyanide-insensitive quinol oxidase and these properties are quite different from those of the bacterial quinol oxidase which belongs to the heme-copper terminal oxidase superfamily. Only little information concerning the molecular structure and enzymatic features of TAO have been available, whereas the bacterial enzyme has been well characterized. In this study, a cDNA encoding TAO from Trypanosoma brucei brucei was cloned into the expression vector pET15b (pTAO) and recombinant TAO was expressed in Escherichia coli. The growth of the transformant carrying pTAO was cyanide-resistant. A peptide with a molecular mass of 37 kDa was found in the cytoplasmic membrane of E. coli, and was recognized by antibodies against plant-type alternative oxidases from Sauromatum guttatum and Hansenula anomala. Both the ubiquinol oxidase and succinate oxidase activities found in the membrane of the transformant were insensitive to cyanide, while those of the control strain, which contained vector alone, were inhibited. This cyanide-insensitive growth of the E. coli carrying pTAO was inhibited by the addition of ascofuranone, a potent and specific inhibitor of TAO ubiquinol oxidase. The ubiquinol oxidase activity of the membrane from the transformant was sensitive to ascofuranone. These results clearly show the functional expression of TAO in E. coli and indicate that ubiquinol-8 in the E. coli membrane is able to serve as an electron donor to the recombinant enzyme and confer cyanide-resistant and ascofuranone-sensitive growth to E. coli. This system will facilitate the biochemical characterization of the novel terminal oxidase, TAO, and the understanding on the mechanism of the trypanocidal effect of ascofuranone.  相似文献   
60.
In order to clarify the histological and immunohistochemical characteristics of suppurative granuloma in abscess-forming granulomatous lymphadenitis (AGL), and the relation between AGL and cat scratch disease (CSD), 36 cases of AGL were studied. The combined results showed that there were two types of suppurative granulomas. The suppurative granulomas histologically revealed small lymphocytes of predominantly T cell phenotype distributed among the epithelioid histiocytes bordering central necrotic areas in the suppurative granulomas. These suppurative granulomas could be further subdivided into two groups, mainly those with and without the intermingling of large transformed cells of B-cell phenotypes: Type B granuloma with large transformed B cells and Type A without large transformed B cells. Both types of granulomas were observed in a varying degree in most cases. According to the predominant type of granulomas, 36 patients with AGL were further classified into two groups: Group I of Type A dominance and Group II of Type B dominance. Warthin-Starry (WS) silver stain positive bacteria, which are said to be a causative agent of CSD, were present in about 50% of both groups. No Brown-Hopps' Gram-positive bacteria, fungus, toxoplasma, Chlamydia or Bacillus Calmette-Guerin antigen were found in any case. Clinically, there was no significant difference between these two groups. On the other hand, the detection of WS-positive bacteria seemed to have some relationship with the duration of disease and the history of exposure to cats, and 70% of AGL cases occurred in autumn without a single concurrent epidemic.  相似文献   
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