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101.
It is generally accepted that the interaction between CD40 and its ligand (CD154) plays a decisive role in contact-dependent help for T and B cells. In CD154-deficient MRL/Mp-Fas(lpr) (MRL/lpr) mice, however, high titres of IgG2a-type autoantibodies against small nuclear ribonucleoproteins (snRNPs) are observed. We successfully isolated two CD154-deficient MRL/lpr Th1 lines, which could provide B cell help for anti-snRNP antibody production. The proliferative responses of the Th1 cell lines were MHC class II (I-Ek)-restricted. Although syngeneic B cell proliferation was induced by Th1 lines in both a contact-dependent and -independent manner, the soluble form of TNF-alpha (sTNF-alpha) was not involved in contact-independent B cell proliferation. On the other hand, both anti-TNF-alpha and TNF-receptor 2 (TNF-R2, p75) monoclonal antibody (MoAb) blocked contact-dependent B cell proliferation, suggesting that the transmembrane form of TNF-alpha (mTNF-alpha)-TNF-R2 co-stimulation participates in B cell activation. Similarly, anti-TNF-alpha and TNF-R2 MoAb inhibited anti-snRNP antibody production in vitro, but anti-CD154 or TNF-R1 MoAb did not. These results indicate that the interaction of mTNF-alpha on activated Th1 cells with TNF-R2 on B cells may be involved in the autoimmunity seen in MRL mice, and that the blockade of CD40-CD154 co-stimulation may not always be able to suppress some Th1-related manifestations of lupus.  相似文献   
102.
A case of bronchial plasmacytoma occurring in a 57- year-old housewife is reported. She had had the productive cough and the "abnormal shadow" in the right lower lobe for three years before admission. On bronchocopy, a tumor was found in the right main bronchus, large enough to obstruct the air way. The tumor was resected through rigid bronchoscope. Histological impression was "plasmacytoma with local amyloid deposit." M-protein was never detected in the serum or urine. Applying the immunoperoxidase technique for the paraffin section, the plasma cells were found to contain only a single type of immunoglobulin, Ig G-L. The differential diagnosis between plasmacytoma and plasma cell granuloma was made, and plasmacytoma was considered to be one type of extranodal malignant lymphoma.  相似文献   
103.
The aluminum (Al) and iron (Fe) chelate complexes of nitrilotriacetate (NTA) cause renal insufficiency when they are administered intraperitoneally to rats. Their effects on bone metabolism were studied in 4 week old Wistar rats. Daily intraperitoneal administration of Al-NTA (3 mg Al/kg for 11 weeks) induced osteomalacia, impaired bone growth, decreased bone mineral density, lower serum PTH levels than normal as well as renal insufficiency. Al staining showed diffuse deposition in the trabecula and a strong linear band of aluminum deposited at the mineralization front and along the cement line. The osteoid seen markedly within the trabecula was probably the decalcified portion of the bone, the calcium apatite of which was defectively fabricated because of diffuse Al deposition in the trabecula. Al deposition along the cement line would make it much more susceptible to external shear stress than normal. Although daily intraperitoneal administration of Fe-NTA (6 mg Fe/kg for 11 weeks) caused impaired bone growth, decreased bone mineral content and renal insufficiency, the osteoid volume did not increase. Fe staining showed that Fe was deposited diffusely in the cytoplasm of osteoblasts. The results of this study demonstrated that during renal insufficiency, different minerals exhibi different modes of action on bone metabolism, and that AI-NTA is useful for experimental animal models of Al-induced osteomalacia in renal insufficiency.  相似文献   
104.
A case with tumorous deformity of the posterior mitral valve leaflet after spontaneous chordal rupture in a child is described. A partial rupture in the chordae tendineae of the posterior mitral leaflet was found by echocardiography in a 9-year-old Japanese boy. Tumorous bulging was gradually developed in the leaflet and was surgically excised 5 years later. Multiple nodular tumors were found on the atrial surface of the posterior mitral leaflet. Histological examination revealed that the tumorous bulging consisted of myxomatous materials in which collagen fibrils and very fine elastic fibers were distributed loosely and irregularly. Normal-looking endothelial cells covered the luminal surface of the bulging lesion. Vimentin-positive spindle-shaped mesenchymal cells were scattered in the bulge area. The labeling index of proliferating cell nuclear antigen (PCNA) in these cells was 29.3%. These spindle cells were positive for matrix metalloproteinase (MMP)-1 in the entire bulge area. The cells and matrix were positive for MMP-2 and tissue inhibitor of MMP (TIMP)-1 in the basal area of bulging, but were weakly positive or negative at the surface area. Reactivity for TIMP-2 in the cells in the bulge area was obviously weaker than that in the cells at the spongiosa of the anterior mitral leaflet, which was obtained from the patient at the valve replacement operation 9 months after the initial operation. These findings indicated that the tumorous deformity of the mitral valve was formed by the overgrowth of valve tissue under the stimulation of mitral regurgitation in this child, and the imbalance of MMP and TIMP might play an important role in the bulge formation.  相似文献   
105.
An electroencephalogram (EEG), is a visible record of the amplified electrical activity generated by the nerve cells of the brain. EEG has produced an abundance of useful information, though it shows only the activity of the immediately underlying cortex. From the beginning in the areas of convulsive disorder and tumor localization, electroencephalography has expanded to become useful not only in many organic brain disorders but also in many extracerebral conditions influencing the central nervous system (ie, metabolic, endocrine, and toxic). It has also shown some usefulness in sleep disorders. Sleep studies on humans are usually performed by using a polygraph to record three types of data: the EEG, the electrooculography (EOG), and the electromyogram (EMG). The EEG is the core measurement of polysomnography. Polysomnography is generally performed in diagnosing a variety of sleep disorders. Other measures used in polysomnography include: 1) Anterior tibialis EMG, 2) Nasal and oral flow, 3) Blood oxygen saturation, 4) Chest and abdominal movement, and 5) Electrocardiogram (EKG). Also different electronic apparatus and equipment for simultaneous and long-lasting observation and recording of varied physiological phenomena and behavioral manifestations (ie, video-electroencephalography with telemetry, topography, power spectrum) were used. However unless electroencephalography is organized and related to medicine and biology much of it will be disregarded and forgotten.  相似文献   
106.
Cellular localization of inflammatory cytokines in human glomerulonephritis   总被引:8,自引:0,他引:8  
We evaluated the expression of inflammatory cytokines in renal tissues obtained from 45 patients with several types of glomerulonephritis. Immunofluorescence studies with specific antibodies to interleukin (IL)-1, IL-1, IL-6, tumour necrosis factor (TNF)-, and TNF- showed intense cytoplasmic staining in the glomeruli and interstitium. Cells positive for these cytokines were found frequently in tissue from patients with lupus nephritis (WHO Class IV) and membranoproliferative glomerulonephritis, and, to a lesser extent, in tissue from patients with mesangial proliferative glomerulonephritis, Henoch-Schönlein purpura nephritis, and minimal change nephrotic syndrome. Most of these cells were dual-stained with a monoclonal antibody to monocytes-macrophages. In situ hybridization for cytokine mRNA, combined with immunoperoxidase staining for monocytes-macrophages, detected IL-1, IL-6, and TNF- mRNA in monocytes-macrophages infiltrating the glomeruli and interstitium. Occasionally, there was weak or moderate immunostaining for IL-1, IL-6, and TNF- in the glomerular mesangial and epithelial cells, but in situ hybridization signals were rarely found in these loci. These findings suggest that infiltrating monocytes-macrophages, rather than resident glomerular cells, are the major source of inflammatory cytokines in human glomerulonephritis.  相似文献   
107.
A case of primary seminal vesicle carcinoma is reported. The tumor was a CA125-producing adenocarcinoma consisting of fine papillary-tubular, intricate branching or anastomosing glandular structures and was composed of small cuboidal, but occasionally hobnailed, cells with mostly clear, but occasionally granular, cytoplasm. Some tumor cells showed evidence of secretion of seromucinous materials into the interpapillary and cystic space. lmmunohistochemically, almost half of the tumor cells expressed a positive reaction with anti-CAl25, a common serological marker for ovarian epithelial carcinomas; however, no tumor cells expressed any other serological tumor markers such as carcinoem-bryonic antigen, α-fetoprotein, human chorionic gonadotropin, prostatic specific acid phosphatase, or prostatic specific antigen. The patient showed a high level of serological CA125, which fluctuated parallel with the growth, removal and recurrence of the tumor. The morphological and immunohistochemical findings suggested a close relationship between the present tumor and clear cell carcinoma of the ovary, which is thought to be of a Müllerian-Wolfian duct origin.  相似文献   
108.
Fanconi-Bickel syndrome (FBS), or glycogen storage disease type XI, is a rare autosomal recessive disorder characterized by hepatorenal glycogen accumulation, Fanconi nephropathy, and impaired utilization of glucose and galactose. Recently, this disease was elucidated to link mutations in the glucose transporter 2 (GLUT2) gene. Only three mutations in three FBS families have been reported. Therefore, it is important to elucidate mutations in the GLUT2 gene in FBS by answering the question of whether the syndrome is a single gene disease. In this report, we describe two patients in two unrelated families clinically diagnosed with FBS. No mutation in the entire protein coding region of the GLUT2 gene was detected in patient 1, which suggested that no mutation existed in the GLUT 2 gene, or that some mutations had affected the expression of the GLUT 2 gene. In patient 2, a novel homozygous nonsense mutation (W420X, Trp at codon 420 to stop codon) was detected. These results support the correlation between GLTU2 gene mutation and FBS syndrome. However, many patients must be analyzed to determine whether other genes are involved in FBS. Received: July 16, 1999 / Accepted: September 3, 1999  相似文献   
109.
Hepatocellular carcinomas (HCCs) were induced in male Fischer 344 rats with dietary 3'-methyl-4-(dimethylamino)-azobenzene treatment and were classified into solid, glandular (well- or poorly differentiated), and trabecular types. Investigation of cell proliferation kinetics and immunohistochemical localization of transforming growth factor alpha (TGF-alpha) demonstrated all solid (n = 24) and poorly differentiated glandular type (n = 6) HCCs to have TGF-alpha-positive nuclei. Nuclear staining of TGF-alpha was also observed in 13 of 28 (46%) trabecular-type HCCs, whereas 12 (43%) exhibited cytoplasmic staining, and 3 (11%) were negative. As for well-differentiated glandular HCCs, 7 of 20 (35%) were positively stained in their nucleus, another 7 (35%) demonstrated antibody binding in the cytoplasm, and 6 (30%) were negative. The order for growth rate evaluated by bromodeoxyuridine (BrdU) labeling was solid (38.22%), poorly differentiated glandular (26.82%), trabecular (7.98%), and well-differentiated glandular (2.57%) types. For trabecular HCCs with nuclear, cytoplasmic, or negative TGF reactions, values were 13.39% (n = 13), 3.61% (n = 12), and 2.01% (n = 3), respectively. Likewise, BrdU-labeling indices for the counterpart groups of well-differentiated glandular type HCCs were 4.53, 1.91, and 1.29%, respectively. The results indicate that TGF-alpha expression might be linked to histopathological differentiation and cell proliferation in rat HCCs.  相似文献   
110.
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