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41.
Policosanol is a new cholesterol-lowering drug isolated and purified from sugar-cane wax. which prevents the development of lipofundin-induced lesions and foam-cell formation in New Zealand rabbits and Wistar rats. This study was conducted to examine the effects of policosanol on foam-cell formation in carrageenan-induced granulomas in rats. Eighteen Wistar rats were randomly distributed in three experimental groups which received orally for 20 days Tween 20 H2O as vehicle (control group) or policosanol at 2.5 or 25 mg kg?1. At the 11th day. lipofundin was injected intrapcritoneally for 8 days to induce formation of foam cells in the granuloma. At day 13, carrageenan was injected subcutaneously for granuloma induction and seven days later animals were killed. A significant reduction of the foam-cell formation in granulomas of policosanol-treated rats was observed. It is concluded that policosanol prevents the development of foam cells in carrageenan-induced granulomas (extravascular medium) in rats. 相似文献
42.
Chronically Trypanosoma cruzi infected "I" rats and syngeneic naive recipients, transferred with a T cell enriched spleen cell population from infected donors, develop an attenuated arthritis when challenged with complete Freund's adjuvant. We report that cyclophosphamide, 40 mg/kg body weight, given 48 h before induction, was able to reestablish or exacerbate adjuvant arthritis in infected and control rats, respectively. Although the T cell enriched spleen cells from infected donors continued to down regulate adjuvant arthritis in syngeneic recipients given cyclophosphamide 48 h before cell transfer, treatment of infected donors with cyclophosphamide, 48 h before cell collection, prevented these cells from exerting such effect when transferred to healthy recipients receiving no cyclophosphamide. It is suggested that cyclophosphamide may primarily affect a suppressor cell population, present in the infected host, with regulatory activity on adjuvant arthritis. 相似文献
43.
Pathological root resorption has clinical symptoms of great importance when it appears in permanent teeth, as its etiology is not always clear. It is important to examine all local and general factors before determining its "idiopathic" cause. A case of spontaneous loss of permanent teeth in a 19 year-old female is presented. Through a meticulous study correlating the clinical history and the evolution of the symptoms, we can suspect that non-dental medical interventions requiring general anesthesia can lead to the loss of permanent teeth through root resorption. 相似文献
44.
Twelve Sardinian patients affected by histologically defined classic Kaposi's sarcoma (KS) were HLA-A, B, C and DR typed. Compared to 220 age and ethnically matched healthy controls, KS patients showed a significant increase in HLA-DR5 (66.6 vs 23.1%, P less than 0.001) and a considerable decrease in HLA-DR3 (8.3 vs 53.6%, P = 0.0055). No definite association was observed for other HLA antigens. These results confirm the existence of an HLA associated genetic control of KS susceptibility and support the hypothesis that HLA-DR5 plays the role of a predisposition marker while HLA-DR3 bears a genetic resistance to the disease. 相似文献
45.
Benito N Moreno A Filella X Miró JM González J Pumarola T Valls ME Luna M García F Rañó A Torres A Gatell JM 《Clinical and diagnostic laboratory immunology》2004,11(3):608-614
We analyzed the characteristics of the inflammatory response occurring in blood during pulmonary infections in human immunodeficiency virus (HIV)-infected patients. A prospective study of consecutive hospital admissions of HIV-infected patients with new-onset radiologic pulmonary infiltrates was carried out in a tertiary university hospital from April 1998 to May 2001. Plasma cyclic AMP receptor protein (CRP), interleukin 1beta (IL-1beta), IL-6, IL-8, IL-10, and tumor necrosis factor alpha (TNF-alpha) levels were determined at the time of admission and 4, 5, and 6 days later. Patients were included in a protocol addressed to study etiology and outcome of disease. A total of 249 episodes of infection were included, with the main diagnoses being bacterial pneumonia (BP) (118 episodes), Pneumocystis carinii pneumonia (PCP) (41 episodes), and mycobacteriosis (36 episodes). For these three patient groups, at the time of admission the median CRP and cytokine levels were as follows: CRP, 10.2, 3.8 and 5 mg/dl, respectively (P = 0.0001); IL-8, 19, 3, and 2.9 pg/ml (P = 0.045); and TNF-alpha, 46.4, 44, and 75 pg/ml, respectively (P = 0.029). There were no significant differences in levels of IL-1beta, IL-6, or IL-10 among the patient groups. A total of 23 patients died. At the time of admission, HIV-infected patients with BP had higher plasma CRP and IL-8 levels than did PCP and mycobacteriosis patients. TNF-alpha levels were higher in patients with mycobacteriosis. An elevated IL-8 level (>61 pg/ml) at the time of admission was an independent factor associated with higher mortality (odds ratio, 12; 95% confidence interval, 1.2 to 235.5). 相似文献
46.
Redefining the significance of aneuploidy in the prognostic assessment of colorectal cancer 总被引:5,自引:0,他引:5
Risques RA Moreno V Marcuello E Petriz J Cancelas JA Sancho FJ Torregrosa A Capella G Peinado MA 《Laboratory investigation; a journal of technical methods and pathology》2001,81(3):307-315
The aberrant content of DNA, or aneuploidy, is a hallmark of tumor cells and may be associated with malignant potential. Based on the hypothesis that aneuploidy, as a form of genetic instability, results in an increased capability to generate cell heterogeneity, we investigated whether a comprehensive assessment of aneuploidy extent and degree might be a reliable indicator of tumor aggressiveness. DNA content was determined by flow cytometry in the infiltrating front of 131 paraffin-embedded primary colorectal carcinomas collected in a prospective design. Enrichment of tumor cells by sample microdissection resulted in neoplastic cell contents above 75%. An estimate of aneuploidy, the aneuploidy index (AI), was calculated as the tumor DNA content adjusted by the percentage of diploid and aneuploid cells in G0/G1. Thirty-nine tumors were diploid, 90 hyperdiploid, and 2 hypodiploid. The mean AI in aneuploid tumors was 1.20+/-0.17 and correlated with Dukes' stage and metastasis (p < 0.05). A high AI (receiver operating characteristic curve cutoff value greater than 1.14) predicted a poorer outcome in univariate (p = 0.004) and multivariate (p = 0.01) analyses. Based on these results, we postulate that aneuploidy is the molecular engine of progression in a subset of colorectal cancers, in which the AI seems to be a sensible and independent gauge of malignant potential. The AI determination may have prognostic application in colorectal cancer, especially in low-grade tumors, which might benefit from coadjuvant therapies. 相似文献
47.
Michael Bilous Mitch Dowsett Wedad Hanna Jorma Isola Annette Lebeau Aberlardo Moreno Frédérique Penault-Llorca Josef Rüschoff Gorana Tomasic Marc van de Vijver 《Modern pathology》2003,16(2):173-182
Knowledge of HER2 status is a prerequisite when considering a patient's eligibility for Herceptin (trastuzumab) therapy. Accurate assessment of HER2 status is essential to ensure that all patients who may benefit from Herceptin are correctly identified. There are several assays available to determine HER2 status: the most common in routine clinical practice are immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH). Various factors can affect the results achieved with these assays, including the assay antibody/probe, the methodology and the experience of personnel. Many countries have implemented national testing guidelines in an attempt to standardize testing procedures and make results more accurate. These guidelines vary in the level of detail and the number of recommendations. This review looks at areas of consensus between the different national testing guidelines and highlights where errors may arise during the testing procedure. The key point underlined by this review is that whatever method is used to test for HER2 status, the technology must be validated first, and there must be regular internal and external quality control and quality assurance procedures. 相似文献
48.
Detection of serum antibodies to CagA and VacA and of serum neutralizing activity for vacuolating cytotoxin in patients with Helicobacter pylori-induced gastritis. 总被引:1,自引:0,他引:1 下载免费PDF全文
M Donati S Moreno E Storni A Tucci L Poli C Mazzoni O Varoli V Sambri A Farencena R Cevenini 《Clinical and Vaccine Immunology : CVI》1997,4(4):478-482
Thirty patients with dyspepsia, with histological diagnosis of gastritis, and with endoscopic diagnosis of peptic ulcer disease (PUD) (n = 13) or nonulcer dyspepsia (NUD) (n = 17) were admitted to the study. Helicobacter pylori vacuolating cytotoxin-producing strains (Tox+) were isolated from 14 (46.7%) patients, whereas non-cytotoxin-producing (Tox-) H. pylori strains were isolated from the remaining patients. Of 30 patients studied, 20 (66.7%) had serum cytotoxin neutralizing activity in vitro. Fourteen patients with Tox+ H. pylori strains showed serum cytotoxin neutralizing activity and serum immunoglobulin G (IgG) and IgA antibodies reactive with both 87-kDa H. pylori vacuolating cytotoxin (VacA) and 128-kDa cytotoxin-associated gene product (CagA) by immunoblotting using native enriched preparations of VacA and CagA proteins from H. pylori culture supernatants as the antigens. A 94-kDa antigen cross-reacting with the 87-kDa VacA protein could be demonstrated in culture supernatant with immune sera from humans and animals. All patients (n = 10) lacking serum neutralizing activity were also negative for IgG or IgA against VacA antigen, whereas 6 of the 10 patients showed IgG serum antibody responses against CagA antigen. The prevalence of antibodies to VacA and CagA antigens was significantly (P < 0.001) higher in patients with gastritis (20 and 26 patients for VacA and CagA, respectively, of 30 patients) than in H. pylori culture-negative controls (0 of 27 for both VacA and CagA) and in randomly selected blood donors (17 and 21 for VacA and CagA, respectively, of 120 subjects). All patients with PUD had antibodies to CagA, whereas 13 of 17 (76.5%) patients with NUD had anti-CagA antibodies. Serum IgG antibodies to VacA were present in 9 (69.2%) patients with PUD of 13 patients and in 11 (64.7%) patients with NUD of 17 patients. Anti-CagA antibodies seemed to correlate better with PUD than anti-VacA antibodies. 相似文献
49.
50.
Twenty-three patients with characteristic hepatic fibrin-ring granulomas were studied. Q fever accounted for 10 cases (43%), visceral leishmaniasis for five cases (22%), boutonneuse fever for two cases (9%), and toxoplasmosis, Hodgkin's disease, and allopurinol hypersensitivity for one case each (4%). The etiology remained undetermined in three cases (13%). This report broadens the range of etiologies of hepatic fibrin-ring granulomas to include boutonneuse fever and toxoplasmosis in the differential diagnosis of ring granulomas, and it could serve as a guideline to the clinician and pathologist for the most frequent categories of disease associated with this morphologic pattern. 相似文献