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101.
Inflammatory mediators in culture filtrates of Escherichia coli.   总被引:2,自引:2,他引:2       下载免费PDF全文
Escherichia coli, when cultured on a simple medium containing only glucose and inorganic compounds, release soluble factors which have a variety of biologic effects on cells in vitro. These low molecular weight (less than 12,000) substances are capable of: a) reversibly inhibiting the migration of macrophages, b) causing chemotactic attraction of neutrophils, c) inducing blast transformation of lymphocytes, and d) producing cytotoxic effects on mouse fibroblasts in culture. Although these activities are functionally similar to those which have been described for various lymphokines obtained from antigen-activated lymphocyte cultures, lymphocyte and bacterial factors which share a given property do not appear to be identical. For example, the bacterial factor which inhibits macrophage migration is partially heat labile and is dialyzable, characteristics which distinguish it from conventional migration inhibition factor. Nevertheless, similarity of function may imply the existence of some degree of chemical homology which would have importance implications concerning the evolution of host-defense reactions. In any case, as is the situation for the lymphokines, the in vitro behavior of the bacterial factors suggest a role for them in in vivo inflammatory responses.  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   
105.
An intracellular protein, dystrophin, plays an important role in keeping muscle fibers intact by binding at its N-terminal end to the subsarcolemmal cytoskeletal actin network and via its C-terminal end to the transmembraneous protein beta-dystroglycan. Duchenne muscular dystrophy is caused by the loss of dystrophin, which can result from the loss of this binding. The N-terminal part of the latter binding site of dystrophin has been well documented using overlay assay and X-ray diffraction assays. However, the binding site at the C-terminal region of dystrophin has not been examined in detail. In the present work, we report a detailed analysis of the C-terminal binding domain as follows. (1). The full binding activity corresponding to the effective binding in vivo is expressed by the dystrophin fragment spanning amino acids 3026-3345 containing the ZZ domain at the C-terminus. Determination of this binding range is important not only for understanding of the mechanism of dystrophy, but also useful for the design of truncated dystrophin constructs for gene therapy. (2). The ZZ domain binds to EF1 domain in the dystrophin fragment to reinforce the binding activity. (3). The cysteine 3340 in the ZZ domain is essential for the binding of dystrophin to beta-dystroglycan. A reported case of DMD due to missense mutation C3340Y may be caused by inability to fix dystrophin beneath the cell membrane. (4). The binding mode of utrophin is different from that of dystrophin. The difference is conspicuous concerning the cysteine residues present in the ZZ domain.  相似文献   
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A typical case of the D uchenne type of progressive muscular dystrophy with autopsy findings was presented. Changes in the myocardial and smooth muscle of many organs were found, and the skeletal muscles also revealed florid changes.
Histopathological examination of the skeletal muscle was made in detail through light and electron microscopic observation.  相似文献   
108.
Recently it has been reported that patients with ulcerative colitis (UC) often have thymus abnormalities, although the precise mechanisms which induce those abnormalities remain unclear. We have examined the effect of serum fractions from patients with UC and other colonic diseases on mouse thymus to clarify the possible existence of factors which have thymus growth activity. These fractions were separated from sera of patients with UC by gel filtration and anion exchange high performance liquid chromatography. In mice given UC serum fractions; (i) remarkable increases in weight and total cell number of the thymus were observed from day 4 to day 9; (ii) a significant increase in the number of peanut agglutinin (PNA)+ thymus cells was demonstrated using flow cytometry on day 9; (iii) on quantitative analysis of surface antigens the percentage of Lyt-2+ thymus cells decreased and that of L3T4+ thymus cells increased remarkably on day 13; the number of bright Thy-1.2+ cells and of dull Lyt-1+ cells increased. In contrast, the serum fractions from patients with other colonic diseases and from normal persons caused little change in mouse thymus throughout the study. The results suggest that factors fractionated from the serum of patients with UC disturb intra-thymic T cell maturation and enhance the proliferation of thymus cells.  相似文献   
109.
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   
110.
The effects of biliary obstruction on the secretory activity and ultrastructure of the exocrine pancreas were studied in rats. Increased volume, protein and amylase secretion were observed in the early periods, under basal conditions and in response to cerulein-secretin stimulation. Bicarbonate concentrations in the pancreatic juice were not significantly altered during the experiments, under either basal or stimulated conditions. The wet weight of the pancreas, and the tissue protein and amylase content of the pancreas increased progressively after bile duct ligation, under basal conditions. Morphological changes were marked in the acinar cells, the most characteristic being an increase in the size and number of zymogen granules and dilatation of the Golgi cisternae. These findings demonstrate a hyperfunctional state of the acinar cells following progressive suppression of granule discharge. It is suggested that the inhibition of granule discharge from acinar cells in rats with prolonged bile duct ligation may be due to the cytotoxic effects of hyperbilirubinemia and inhibition of normal mitochondrial function.  相似文献   
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