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1.
Hepatic angiomyolipoma is a rare tumor composed of spindle-shaped and epithelioid smooth muscle cells, adipose tissue, and proliferating blood vessels. We report the first documented case of this tumor developing in a patient with ulcerative colitis. A solitary tumor (7.5×7.5×7cm) was detected in the left lateral segment of the liver and a left hepatic lobectomy was performed. The diagnosis of angiomyolipoma was confirmed by a pathological examination. We also review the literature on previously reported cases of hepatic angiomyolipoma.  相似文献   
2.
BACKGROUND: Atopic dermatitis (AD) is a chronic inflammatory skin disease associated with tissue eosinophilia and the activation of T lymphocytes. The novel eosinophil chemoattractants, eotaxin and monocyte chemotactic protein (MCP)-4, are up-regulated at sites of allergic inflammation, yet their contribution to the pathophysiologic mechanisms of AD remains to be determined. OBJECTIVE: We sought to investigate the expression of eotaxin and MCP-4 in acute and chronic lesions from patients with AD and to determine their relationship to the numbers of resident inflammatory cells. METHODS: With use of in situ hybridization, the expression of eotaxin and MCP-4 messenger RNA (mRNA) in skin biopsy specimens from patients with acute and chronic AD skin lesions was compared with that of uninvolved skin from these patients and skin from healthy volunteers. RESULTS: There was a constitutive expression of eotaxin and MCP-4 mRNA in skin biopsy specimens from healthy subjects. Positive signal for chemokine mRNA was observed both within the epidermis and inflammatory cells (macrophages, eosinophils, and T cells) of the subepidermis in AD skin lesions. Within the subepithelium acute and chronic skin lesions exhibited a significant increase in the numbers of eotaxin and MCP-4 mRNA-positive cells compared with uninvolved skin (P <.01), whereas the numbers of eotaxin and MCP-4 mRNA-positive cells were significantly higher in chronic AD compared with acute AD skin lesions (P <.005, P <.001, respectively). Correlations were observed between the expression of eotaxin and MCP-4 mRNA and the presence of eosinophils and macrophages, respectively, in AD lesions (r(2) = 0.84, r(2) = 0.94). CONCLUSION: There is an increased expression of eotaxin and MCP-4 in acute and chronic lesions, suggesting that these chemotactic factors play a major role in the pathophysiologic mechanisms of AD.  相似文献   
3.
Anti-centromere autoantibodies (ACA) are commonly found in the serum of patients with a limited type of scleroderma and other systemic autoimmune diseases. CENP-A is one of the major antigens against ACA and a histone H3-like protein. To analyse the autoantigenic epitopes of CENP-A, a series of truncated peptides of human CENP-A were expressed in Escherichia coli and immunoblotting analysis was performed with 91 ACA+ sera. Eighty sera (88%) with the ACA reacted to the 52-amino acids N-terminal region which is not homologous to H3, while no sera reacted to the C-terminus which has a sequence similarity with H3. Moreover, ELISA was also employed in this study using two synthetic peptides corresponding to the amino acid sequences 3-17 (peptide A) and 25-38 (peptide B). Peptides A and B were reactive to 78 (86%) and 79 (87%) of ACA, respectively. Core antigens of hepatitis B virus (HBV) and hepatitis C virus (HCV) have similar sequences to peptide A and/or peptide B, but three sera containing HBV without ACA and five sera containing HCV without ACA were found to be reactive to neither peptide. Centromere localization of CENP-A is dependent on the H3-like C-terminal domain which is not autoantigenic, while the antigenic N-terminal domain, which might play unidentified functional roles, should be an important region for the induction of ACA.  相似文献   
4.
Optimal activation of human T cells mediated by ligation of CD3/T cell receptor (TcR) complex requires co-stimulatory signals. These can be provided by the adhesive interaction between receptor molecules on T cells and their counter-receptors on antigen-presenting cells. Soluble ICAM-3, anti-ICAM-3 and anti-CD3 mAb were utilized to address the role of the ICAM-3/LFA-1 pathway in TcR/CD3-dependent or -independent T cell activation. Immunoaffinity-purified ICAM-3 co-immobilized with suboptimal concentrations of anti-CD3 monoclonal antibody (mAb) stimulated T lymphocytes as monitored by the expression of the lymphocyte activation antigens CD25 and CD69. The mechanism underlaying this activation appear to involve the interaction of ICAM-3 with a β2 integrin, likely to be LFA-1, since mAb to the CD18 chain completely inhibited T cell activation. Similar experiments demonstrated that anti-ICAM-3 mAb were able to co-stimulate both resting (cord blood) and activated (T cell clones) T lymphocytes. On the contrary, anti-ICAM-1 mAb were only co-stimulatory for CD25 expression on activated but not on resting T cells. In addition, we have found that some γδ T cell clones bearing the Vδ1 segment were activated by direct mAb engagement of ICAM-3 in the absence of TcR/CD3 occupancy. Furthermore, immobilized anti-ICAM-3 mAb also induced development of dentritic processes. In conclusion, our data suggest that ICAM-3 on the surface of both T cells and antigen-presenting cells plays an essential role in the initiation of the immune response.  相似文献   
5.
Centromere protein-C (CENP-C), one of the centromere autoantigens and components of the inner plate of the kinetochore, is suggested to make a dimer at the C-terminus. In order to investigate the presence of conformation-specific anti-centromere antibodies (ACA) to the dimer form, the C-terminal 124 amino acids (CF-124) were expressed in Escherichia coli, affinity purified and chemically cross-linked. Immunoblotting was utilized to compare the reactivities between the dimers and the monomers against 58 ACA(+) sera. The reactivities of the dimers were obviously higher in both IgG and IgM responses. The dimer was still more reactive than the glutathione S-transferase-fused monomer in some sera. Two kinds of CF-124 mutant (each contained one amino acid change at the N-terminal region of CF-124) and two cut segments of CF-124 (67 N-terminal amino acids and 58 C-terminal amino acids) were also examined. The former two mutants decreased the dimerization activity. The latter two mutants lost both activities except for the faint dimerization activity of the N-terminal half. Affinity-purified antibodies with CF-124 in a liquid phase containing the co-purified GroE protein of E. coli, GroEL, reacted to the centromere in culture cells. In conclusion, there are heterogeneous autoepitopes including some conformational epitopes at the C-terminal CENP-C.  相似文献   
6.
7.
Discograms of images that were eccentrically dyed because of insufficient infiltration of contrast medium are difficult to classify into the usual past discogram patterns. In this study, these types of images were detected in 40 discs of 36 patients with lumbar disc disease. We classified these images into the following three types, and analyzed the dye mechanisms in each case by computed tomography discographic findings: (1) type A (image of the annulus fibrosus only). Nine discs in nine cases. A part of the marginal annulus fibrosus was dyed. (2) type B (image of the right or left half of the nucleus pulposus). Eighteen discs in 15 cases. Unilateral dyeing was considered nucleus pulposus existing in the central region of the disc. (3) type C (partial image of the superior or inferior half of the nucleus pulposus). Thirteen discs in 12 cases. Only the superior or inferior half showing a cotton-ball pattern was dyed.  相似文献   
8.
Nakano Y  Sakai H  Muro S  Hirai T  Oku Y  Nishimura K  Mishima M 《Thorax》1999,54(5):384-389
BACKGROUND: The low attenuation areas on computed tomographic (CT) scans have been reported to represent emphysematous changes of the lung. However, the regional distribution of emphysema between the inner and outer segments of the lung has not been adequately studied. In this study the regional distribution of low attenuation areas has been compared by quantitative CT analysis and the contribution of the regional distribution to pulmonary function tests evaluated in patients with chronic obstructive pulmonary disease (COPD). METHODS: Chest CT images and the results of pulmonary function tests were obtained from 73 patients with COPD. The lung images were divided into inner and outer segments in the upper (cranial), middle, and lower (caudal) sections. The percentage ratio of low attenuation area to corresponding lung area (LAA%) was then calculated. The LAA% of each segment was also compared with the results of pulmonary function tests. RESULTS: The mean (SD) LAA% of the inner segment was 39.1 (18.5) compared with 28.1 (13.2) for the outer segment (p<0.0001). Linear and multiple regression analyses revealed that airflow limitation is closely correlated with the inner segment LAA% of the lower lung. In contrast, the carbon monoxide transfer factor is closely correlated with the inner segment LAA% of the upper lung. CONCLUSION: Low attenuation areas on CT scans are more often found in the inner segment of the lung than in the outer segment, and the contribution of the inner segment to pulmonary function tests may be greater than the outer segment.  相似文献   
9.
We have observed an inhibitory action of magnolol on the production of leukotriene (LT) C4 and LTB4, important lipid mediators in allergy and inflammation. IgE- and A23187-stimulated production of LTC4 and LTB4 was measured by radio-immunoassay (RIA) in the absence or presence of various concentrations of magnolol in intact rat basophilic leukemia (RBL)-2H3 cells. Magnolol dose-dependently inhibited synthesis of LTC4 and LTB4. Magnolol inhibited the IgE-mediated increase of intracellular calcium ion concentration, resulting in the inhibition of cytosolic phospholipase A2 (cPLA2) and possibly 5-lipoxygenase (5-LO), both calcium ion-dependent enzymes. In cell-free studies magnolol inhibited LTC4 synthase activity. LTA4 hydrolase activity was only inhibited at the higher concentration (2.5 x 10(-5)M). These results indicate that magnolol inhibits production of LTs by inhibiting PLA2, 5-LO, LTC4 synthase and LTA4 hydrolase which are essential for LT-synthesis. Magnolol may have anti-allergic effect by blocking LT-synthesis.  相似文献   
10.
Summary Two children, aged 18 months and 6 years, who had Recklinghausen's disease, had occlusion of cerebral arteries. One child had no motor deficit but the other had right hemiparesis and partial occlusion of the left posterior cerebral artery, a fact not found in the literature.  相似文献   
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