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991.
992.
Monteseirín J Bonilla I Chacón P Vega A Camacho MJ Guardia P Conde J Sobrino F 《Allergy》2003,58(10):1027-1032
BACKGROUND: CD14 is a most important monocyte surface molecule. Recently, it has been reported that there is an important relationship between CD14 and immunoglobulin E, and that regulation of CD14 expression is an effector mechanism mediating apoptosis of monocytes. OBJECTIVE: The present study was designed to determine whether specific allergens were able to modulate CD14 expression and apoptosis by monocytes from allergic patients or whether specific immunotherapy (IT) might affect these processes. METHODS: One group of adult allergic asthmatic patients had received IT for the previous 3 years. Another similar group was not treated with IT. We challenged peripheral blood monocytes from both groups of asthmatic patients in vitro with the specific allergen that produced clinical symptoms in asthmatic patients. The cells were also challenged with allergen to which the patients were not sensitive. Monocytes from normal subjects were also challenged with allergens. Expression of CD14 on the monocyte surface was analyzed by flow cytometry, and soluble CD14 (sCD14) in culture supernatant by enzyme-linked immunosorbent assay. The three groups of subjects were challenged with allergens, and apoptosis was analyzed by flow cytometry. RESULTS: When monocytes from non-IT-treated asthmatic patients were cultivated with the allergens to which the patients were sensitive, a significant up-regulation on the monocyte surface was observed compared with results from the healthy group (P < 0.003) and from the IT asthmatic group (P < 0.003). A significantly higher sCD14 level was observed in the culture supernatant of the monocytes from the IT asthmatic group were observed compared with those from the healthy group (P < 0.001) and those from the non-IT asthmatic group (P < 0.001). A significantly higher apoptosis level was observed in monocytes from the IT asthmatic group compared with those from the healthy group (P < 0.001) and those from the non-IT asthmatic group (<0.001). CONCLUSIONS: We present evidence that the expression of CD14 on the surface of monocytes and the apoptosis of the same cells can be modulated by an allergen-dependent mechanism. These processes can be affected by IT. 相似文献
993.
994.
Alcalá B Salcedo C Arreaza L Berrón S De La Fuente L Vázquez JA 《Journal of medical microbiology》2002,51(12):1102-1106
During 1996 and 1997 an epidemic wave of meningococcal disease took place in Spain. Initial studies described the antigenic expression of the epidemic strain as C:2b:P1.2,5 and proposed that it was a variant of the previously identified Spanish C:2b:non-subtypable epidemic strain. To clarify this hypothesis, 1036 C:2b:P1.2(5) and 76 C:2b:NST isolates obtained during 1992-1999 were analysed by pulsed-field gel electrophoresis. The majority of the C:2b:P1.2,5 and C:2b:P1.2 isolates showed one of two very closely related profiles. During the epidemic period, 80% of the C:2b:NST strains showed these two pulsotypes. However, before the epidemic wave, most of these C:2b:NST strains (60%) showed a profile that was found infrequently among C:2b:P1.2,5 and C:2b:P1.2 isolates. A similar evolution was observed in C:2b:P1.5 isolates. Thirty-four C:2b:P1.2(5) and 10 C:2b:NST isolates, exhibiting representative pulsotypes, were subjected to multi-locus sequence typing. Isolates belonging to both A4 and ET-37 lineages were identified. These data point to the possibility that the A4 cluster has displaced the ET-37 complex among serogroup C meningococci in Spain. 相似文献
995.
Amundsen SS Naluai AT Ascher H Ek J Gudjónsdóttir AH Wahlström J Lie BA Sollid LM 《Tissue antigens》2004,64(5):593-599
Abstract: In order to extend our previous findings of genetic linkage to the CD28/CTLA4/ICOS region on chromosome 2q33 ( CELIAC3 ) in coeliac disease (CD), we have investigated 22 genetic markers in 325 Norwegian/Swedish multiplex and simplex CD families. We found both linkage and association with several markers, primarily in the multiplex material. We observed strong linkage disequilibrium (LD) between SNPs (Single Nucleotide Polymorphisms) within an LD block delimited by MH30 and D2S72. A haplotype of this region marked by the alleles −1147*T: + 49*A:CT60*G:CT61*A was significantly associated with CD, suggesting that one or more polymorphisms of this haplotype, possibly −1147*T, are involved in CD susceptibility. The CT60 SNP, a polymorphism found to be most strongly associated with some other immune-mediated diseases, was not associated with CD, as this SNP was part of both associated and non-associated haplotypes. Moreover, our results suggest that CELIAC3 harbours several independent loci contributing to CD susceptibility. 相似文献
996.
Diagnosis ofMycoplasma pneumoniae infection by microparticle aggluination and antibody-capture enzyme-immunoassay 总被引:4,自引:0,他引:4
J. M. Echevarría P. León P. Balfagón J. A. López M. V. Fernández 《European journal of clinical microbiology & infectious diseases》1990,9(3):217-220
The performance of two new commercial assays for the serological diagnosis ofMycoplasma pneumoniae infection (microparticle agglutination and antibody-capture enzyme-immunoassay) was studied using a panel of 169 serum samples from patients withMycoplasma pneumoniae pneumonia and a control group. Both assays were shown to be sensitive and specific for diagnosis. The performance of the capture immunoassay, however, decreased in older patients, probably due to its inability to detect cases of reinfection without IgM antibody response. 相似文献
997.
Herein we report the clinicopathological features of four cases of pulmonary artery sarcoma that appeared at our institution during a period of 30 years. The patients, 2 males and 2 females, were 50–62 years old. Tumour was found in the pulmonary trunk and right pulmonary artery in all cases, in the pulmonary valve and left pulmonary artery in three of the four cases, and in the right ventricular outflow tract in one case. There was direct extension or metastases to the lungs in two cases, the heart in one case, mediastinum or lymph nodes in two cases and the pleura in one case. Ultrastructural examination in one case revealed cells with features of smooth muscle cells and myofibroblasts. Immunohistochemical examination of three cases gave the following results: vimentin and smooth muscle specific actin was positive in all three cases, desmin in one case and cytokeratin in one case. No positivity was found for Factor VIII. This and other studies indicate that histologically most pulmonary artery sarcomas are leiomyosarcomas or undifferentiated spindle cell sarcomas. Immunohistochemical and ultrastructural examinations favour an origin from myofibroblasts, probably derived from multipotent (undifferentiated) cells in the wall of the vessel. Most lesions show extensive intrathoracic growth although they rarely metastasize outside the thoracic cavity. They have a poor prognosis although some cases are currently being diagnosed during life. 相似文献
998.
The characteristics of 22 atrial receptors in 15 normotensive adult male Wistar rats were investigated. All the receptor afferents were included in the C-fibre group with conduction velocities from 0.4 to 1.2 m/sec. No atrial medullated receptors or ventricular C-fibre endings were found. Two receptors were located in right atrium and 2 receptors throughout left atrium. Upon elevation of the left atrial pressure the receptor discharge was markedly elevated with thresholds from 2.5 to 9 mmHg in mean left atrial pressure. Ten of the atrial receptors displayed a clear cardiac rhythmicity upon activation and the discharge correlated with the v-wave, indicating distension as the cause of receptor activation. The maximal firing rate in most receptors was very high (up to 70 Hz), but 8 receptors had maximal firing rates below 25 Hz. These low frequency receptors had higher threshold and showed a more irregular firing. Thus, there is a substantial population of atrial receptors with vagal non-medullated afferents in the rat heart and the thresholds for many of these receptors are so low that they are likely to be active during normal conditions. 相似文献
999.
Antibody production and DNA synthesis of human lymphocyte subpopulations induced by PPD tuberculin. 总被引:2,自引:1,他引:2 下载免费PDF全文
O Ringdn B Rynnel-Dag T Kunori A Freijd E Mller 《Clinical and experimental immunology》1979,36(3):528-535
Purified protein derivative (PPD) of tuberculin was found to induce antibody secretion and DNA synthesis in human lymphocytes from blood, spleen, tonsil and lymph node. Antibody secretion was measured as plaque-forming cells (PFC) against fluorescein isothiocyanate (FITC) coupled sheep red blood cells (SRBC) in a haemolysis-in-gel assay. Peak antibody secretion by 100 micrograms/ml of PPD was usually seen on day 6 for blood lymphocytes, and varied from day 3 to day 6 for spleen cells. Peak DNA synthesis for blood lymphocytes stimulated by various concentrations of PPD ranged from day 4 to day 7. The highest number of PFC in tonsil and spleen cells was induced by PPD compared to Staphylococcus aureus bacteria Cowan 1, lipopolysaccharide (LPS) and pokeweed mitogen (PWM). Antibody secretion by PPD was not affected when phagocytic cells were removed by iron treatment. PPD stimulated a higher DNA synthesis in unseparated lymphocytes or mixtures of T and B cells than in enriched T or B cell suspensions. PPD did not induce PFC in B cells enriched by the removal of sheep erythrocyte rosette-forming cells (E-RFC). However, more PFC were stimulated by PPD in enriched E-RFC compared to unseparated lymphocytes, which may indicate that most of the FITC-SRBC reactive B cells also form rosettes with SRBC. 相似文献
1000.
Radhika S Bakshi A Rajwanshi A Nijhawan R Das A Kakkar N Joshi K Marwaha RK Rao KL 《Diagnostic cytopathology》2005,32(5):281-286
Malignant renal neoplasms are common solid tumors in pediatric oncology practice. These include the common Wilms' tumor/nephroblastoma and the uncommon neoplasms such as clear-cell sarcoma of the kidney (CCSK), rhabdoid tumor, renal-cell carcinoma, and others. The aim of this study was to describe in detail the cytopathological features of the histopathologically proven uncommon pediatric renal tumors. Aspirates from Wilms' tumor, which are mesenchyme predominant, show clusters of spindle cells associated with the matrix material. Evidence of rhabdomyoblastic differentiation may be present. CCSK, classic subtype, is characterized by round to oval cells arranged perivascularly and also in sheets and clusters intimately associated with a metachromatic matrix mucopolysaccharide material better appreciated in May-Grunwald-Giemsa (MGG)-stained smears. The cells also have more abundant cytoplasm and may show nuclear grooves. Spindle-cell pattern of CCSK is difficult to diagnose on aspiration cytology. Renal-cell carcinoma of childhood shows similar cytological features as its adult counterpart. Rhabdoid tumor of the kidney is characterized by a monomorphic population of cells with abundant cytoplasm, eccentric nuclei with prominent nucleoli. Intrarenal yolk sac tumor is a rare neoplasm and shows severely pleomorphic cells on aspiration.Awareness of these entities is important for the practicing cytopathologist. Further, non-Wilms' renal malignant neoplasms must be distinguished from the common Wilms' tumor so that appropriate chemotherapy protocols may be instituted in cases where the tumor is in an advanced stage of malignancy. 相似文献