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991.
N. Freudenberg P. Rahner C. Darda U. N. Riede M. Schubert K. Frenzer-Welle A. Kiss G. Veres T. Nees R. Lamers C. Kortsik 《Virchows Archiv : an international journal of pathology》1996,428(3):187-194
We investigated the reaction of the cellular immune system of liver and blood in the C57BL/6 mouse to a metastasizing Lewis lung carcinoma. The cellular immune system of the liver consists of mature and immature macrophages, B-cells, T-cells including their subpopulations, and natural killer cells, and their percentage frequencies differ significantly from those in the corresponding mononuclear blood cell (MBC) compartment. This suggests that the hepatic immune cells represent a system with autonomous function showing a typical homing of its members. Imminent metastasis to the liver is signalled by impressive alterations in the percentage frequencies of nonparenchymal liver cells (NPLC). There are a dramatic loss of mature macrophages, an increase in immature macrophages, a reduction of T-helper cells leading to a low CD4/CD8 ratio, and an increase in natural killer cells. In the blood, the corresponding precursor cells show comparable changes with a delay of at least 2 days. Early metastasis is accompanied by a significant increase in mononuclear NPLC producing tumour necrosis factor . The alterations in percentage frequencies of the NPLC during tumour metastasis differ markedly from the changes in these cells in the liver during endotoxinaemia. 相似文献
992.
IL-10 stimulates production of platelet-activating factor by monocytes of patients with active systemic lupus erythematosus (SLE) 总被引:2,自引:0,他引:2
Bussolati B Rollino C Mariano F Quarello F Camussi G 《Clinical and experimental immunology》2000,122(3):471-476
IL-10 displays modulatory properties on the synthesis of platelet-activating factor (PAF), a potent inflammatory mediator of vascular injury. Despite the fact that IL-10 is considered to be an anti-inflammatory cytokine, IL-10 levels correlate with disease activity in SLE. Moreover, in SLE IL-10 is unable to exert its immunosuppressive and anti-inflammatory effects. We have investigated the ability of IL-10 to stimulate PAF production from monocytes of SLE patients. Spontaneous and IL-10-stimulated PAF production by peripheral blood monocytes was measured in active (n = 13) and inactive (n = 14) SLE patients and in 15 normal control subjects. We observed that monocytes derived from patients with active SLE, but not from controls or inactive SLE, spontaneously produced significant amounts of PAF. Moreover, IL-10 enhanced the synthesis of PAF from monocytes of active SLE patients only. IL-10-induced PAF production correlated with the severity of the disease and with the extent of proteinuria. These results indicate that IL-10 only stimulates the synthesis of PAF from monocytes of SLE patients when immunologically active, suggesting that IL-10 may possess a paradoxical proinflammatory effect in SLE by promoting the production of PAF, a secondary mediator of inflammation. 相似文献
993.
Alteration of E-cadherin-mediated adhesion protein is common,but microsatellite instability is uncommon in young age gastric cancers 总被引:3,自引:0,他引:3
AIMS: Gastric adenocarcinoma in young patients has been considered to differ in many ways from gastric carcinoma in older patients. This study was designed to determine the clinicopathological features and molecular mechanisms. METHODS AND RESULTS: Based on 4123 patients of gastric cancer in Seoul National University Hospital, 135 patients (3.3%) were chosen by the age of 30 years or younger. Expression of E-cadherin, beta-catenin, p53 and Epstein-Barr virus (EBV) was analysed using the tissue array method in formalin-fixed paraffin-embedded specimens and microsatellite instability (MSI) was determined. As a control, 320 cases of older patients were compared. Gastric adenocarcinoma of young patients revealed significant female predominance, type IV gross type, proximal location, diffuse type and frequent lymph node metastasis. In-situ hybridization for EBV showed higher positivity in young patients (9/78, 11.5%) than in older ones, but not statistically significant. In EBV+ cases, p53 over-expression was significantly higher in young patients than older patients (P < 0.05). Alteration of E-cadherin or beta-catenin was significantly higher in younger patients than in older patients (P < 0.05). Overall survival was significantly poorer in younger patients than older ones. The frequency of MSI was rare (1.3%, P < 0.05) in young patients compared with older patients (9.3%). CONCLUSIONS: These data indicate that gastric adenocarcinoma of young patients has a poor prognosis, possesses aggressive histopathological features, exhibits reduced expression of E-cadherin and beta-catenin, and demonstrates lower MSI than tumours in older patients. 相似文献
994.
Kitamura M Matsumiya K Nishimura K Yamanaka M Matsumoto K Okuyama A 《American journal of reproductive immunology (New York, N.Y. : 1989)》2000,44(4):193-196
PROBLEM: Hepatocyte growth factor (HGF) exists abundantly in seminal plasma and its receptor, c-met, is expressed on spermatozoa. Considering its motogenic activity, we speculated that HGF might affect the movement ability of spermatozoa. METHODS: Recombinant HGF was added to washed spermatozoa and their movements were analyzed using a computer-assisted sperm analyzer. The concentration of HGF in the seminal plasma of infertile patients (n = 83) was measured by ELISA, and the data were compared with their hormonal profile and semen parameters. RESULTS: The HGF physiological concentration (1 ng/mL) maintained the motility of sperm after a long incubation, though the difference was not statistically significant. Recombinant HGF did not affect the linearity or frequency of movement, which suggested that it does not evoke the hyperactivation of spermatozoa. The concentration of HGF in seminal plasma did not correlate with any clinical parameter of the patients. CONCLUSIONS: These findings contradict the theory that HGF controls the movement of sperm. The main role of this axis in the male reproductive system might be maturation in the epididymis. 相似文献
995.
David Barnes 《Methods in Cell Science》1986,10(2):69-74
Summary Methods are presented for the quantitative assay of proteins influencing cell attachment and spreading. These include assays in which cell-substratum interactions are quantitated directly and a serum-free assay in which cell growth is dependent on attachment under substratum-limited conditions. Procedures are also presented for the identification of active sites of substratum molecules through the use of antibodies and synthetic peptides that are inhibitory for cell attachment. 相似文献
996.
Small pieces of tissue isolated from abdominal sympathetic ganglia in aged male patients were cultured in a chemically defined, serum-free medium. The growth of neurites from pieces of ganglia in cultures with and without 50 ng/ml mouse 2.5S nerve growth factor (NGF) was compared. The NGF stimulated significantly greater regeneration of neurites, causing the growth of long fibers from the ganglion pieces. Many short neurites grew, even in the absence of the NGF, but these were generally short, except for long neurites generated in several nerve cells. A method was devised for the evaluation of NGF-dependent growth of neurites in the culture. The rate of the NGF-dependent growth of neurites, which was calculated by the difference in the total lengths of the NGF-dependent neurites between 2- and 4-day-old cultures, was approximately 160 micron/day. The results indicate that although the growth of neurites from some sympathetic nerve cells of the aged human become independent of the NGF, most of the nerve cells remain dependent on the NGF, even in the stage of senescence. 相似文献
997.
Biological Properties of Interleukins 总被引:3,自引:0,他引:3
998.
A case of multiple myeloma (IgA-Λ) with marked granulocytosis, which measured up to 9.9×104/mm3 , Is described. Matured neutrophiles were predominant and blasts were not found in the peripheral blood. The serum granulocyte colony-stimulating factor (G-CSF) was notably elevated. The disease ran a chronic course and granulocytosis and elevated serum G-CSF continued. The patient developed atelectasis and bronchopneumonia, and died of respiratory failure. At autopsy, bone marrow showed marked myeloid hyperplasia in varying states of differentiation. The enlarged spleen also disclosed numerous myeloid cells of varying differentiation. Small aggregations of atypical plasma cells were present in the marrow and spleen. Immunohisto-chemically, atyplcal plasma cells were positive for anti-G-CSF antibody, which Indicated G-CSF secretion from the myeloma cells. To our knowledge, this is the first reported case of G-CSF-producing multiple myeloma. 相似文献
999.
Specificity and sensitivity of the IgM capture immunoassay: studies of possible factors inducing false positive or false negative results 总被引:4,自引:0,他引:4
The specificity and sensitivity of the IgM-capture immunoassay (IgM-CI) were evaluated for detection of rubella specific IgM and hepatitis B core (HBc) specific IgM. For rubella specific IgM, antibodies bound to the solid phase were detected by haemadsorption and for HBc specific IgM, by using HBc antigen (HBcAg) and radiolabelled IgG anti-HBc. Rheumatoid factor (RF) was found to interfere in the test for HBc specific IgM because IgM-RF bound to the solid phase reacted with aggregated radiolabelled HBc specific IgG. This false positive reaction did not occur when radiolabelled F(ab')2 was used instead of the whole IgG molecule. HBcAg purified from biological fluids might be coated with host IgG and under these conditions, HBcAg could react with RF. It was also demonstrated that high levels of IgG antibodies could interfere with IgG anti-mu coated-surface by means of non-immunological protein-protein interactions. In fact, IgG did not interfere in the rubella assay, whereas it did in the very sensitive anti-HBc test. To prevent this false-positive reaction, different dilution media were tested. Only the addition of non-specific IgG and fetal calf serum (FCS), to the dilution medium, seems to improve the specificity of the test. Furthermore, in order to decrease this non-specific IgG-IgG interaction and an occasional prozoning phenomenon, the dilution of serum to be tested was taken into account. Parameters considered to decrease sensitivity were also studied. RF, anti-F(ab')2 antibodies and non-specific IgM did not decrease significantly the sensitivity of the assay. 相似文献
1000.
探讨以纤维蛋白胶(fibrin sealant,FS)为载体,复合rhBMP-2\bFGF的注射型骨修复材料,修复犬桡骨节段性缺损的作用,为其临床应用提供实验依据.实验分为:实验组(FS bFGF rhBMP-2)、对照组(FS).于12只成年健康家犬右侧桡骨中上段造成2cm缺损,制成犬桡骨2cm骨缺损实验模型,然后严密缝合皮下组织及皮肤,将实验材料经伤口周围正常皮肤注射到骨缺损处,术后4、8、16、24w进行放射学检查,术后24w,标本进行组织学和骨密度检查,研究其成骨效应.结果表明:实验组骨缺损区在成骨活跃程度、骨密度和再生髓腔结构等方面均显著优于对照组,使骨缺损得到了成功的修复(P<0.01).以纤维蛋白胶为载体复合rhBMP-2和bFGF的注射型骨修复材料,具有高效的骨修复能力,对犬的骨缺损有很好的修复效果. 相似文献