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21.
Proliferating cell nuclear antigen assessed by a computer-assisted image analysis system in patients with chronic viral hepatitis and cirrhosis 总被引:3,自引:0,他引:3
M. F Donato E. Arosio V. Monti P. Fasani D. Prati A. Sangiovanni G. Ronchi M. Colombo 《Digestive and liver disease》2002,34(3):197-203
BACKGROUND: Assessment of liver cell proliferation by immunodetection of proliferating cell nuclear antigen may predict regenerative potential and survival of liver and hepatocellular carcinoma risk in patients with chronic viral hepatitis. AIM: To evaluate proliferating cell nuclear antigen status and its clinical significance in a large cohort of patients with chronic viral hepatitis and different degree of liver damage by a computer assisted imaging analysis system. MATERIALS: Liver biopsies from 358 patients with chronic hepatitis (259 males, 49 years, 63% with hepatitis C infection, 27% with hepatitis B virus, 10% with multiple infections) were studied. METHODS: Proliferating cell nuclear antigen was localised by immunoperoxidase on microwave oven pre-treated formalin-fixed, paraffin embedded sections using PC10 monoclonal antibody. Proliferating cell nuclear antigen labelling index was calculated by an automated imaging system (Immagini e Computers, Milan, Italy). RESULTS: Mean proliferating cell nuclear antigen labelling index ranged from 0.1% for patients with minimal changes to 3.6% for those with cirrhosis and hepatocellular carcinoma. Overall, proliferating cell nuclear antigen labelling index was higher in males, in older patients, in multiple infections and in hepatitis C virus compared to hepatitis B virus related cases. By linear regression analysis, proliferating cell nuclear antigen labelling index correlated with older age, male gender; higher transaminase levels, hepatitis C virus, higher histological gradIng and staging: by multivariate analysis male gender, hepatitis C virus, higher grading and staging resulted as independent variables. Both hepatitis C virus or hepatitis B virus cirrhotics had similar liver cell proliferation rate but those with hepatitis B virus had higher prevalence of liver cell dysplasia with respect to those with hepatitis C virus. CONCLUSIONS: Proliferating cell nuclear antigen labelling index was a reliable assay for assessing liver cell proliferation rate in patients with chronic viral hepatitis and correlated with liver disease severity 相似文献
22.
Outcome of anti-HBe positive chronic hepatitis B in alpha-interferon treated and untreated patients: a long term cohort study 总被引:27,自引:0,他引:27
Brunetto MR Oliveri F Coco B Leandro G Colombatto P Gorin JM Bonino F 《Journal of hepatology》2002,36(2):263-270
BACKGROUND/AIMS: We studied the influence of biochemical and virologic patterns and interferon on the outcome of anti-HBe positive chronic hepatitis B in 164 (103 treated) consecutive patients, followed-up prospectively for a mean of 6 years (21 months-12 years). METHODS: Histology, biochemical and virologic profiles were characterized by monthly monitoring during the first 12 months of follow-up. Thereafter patients underwent blood and clinical controls every 4 and 6 months, respectively. Cirrhosis at follow-up histology or end stage complications of cirrhosis served as end points for the analysis of factors influencing disease progression in patients with baseline chronic hepatitis or cirrhosis, respectively. RESULTS: Disease progression was associated with older age (P<0.001), absence of previous HBeAg history (P=0.017) and higher serum HBV-DNA levels (P=0.009) (more frequently observed in unremitting disease profile, P=0.012) at multivariate analysis. Fluctuations of IgM anti-HBc levels (associated with disease exacerbations, P=0.045) correlated with end stage complications in cirrhotics (P=0.011). Disease improved in 14.6 and 1.6% of treated and untreated patients, respectively (P=0.015): interferon slowed disease progression (P<0.001). CONCLUSIONS: The outcome of anti-HBe positive chronic hepatitis B is worsened by older age and persistent viral replication or hepatitis exacerbations in chronic hepatitis or in cirrhotic patients, respectively. Interferon reduces by 2.5-folds disease progression. 相似文献
23.
Anti-beta 2 glycoprotein I antibodies in centenarians 总被引:2,自引:0,他引:2
Meroni PL Mari D Monti D Coppola R Capri M Salvioli S Tincani A Gerli R Franceschi C 《Experimental gerontology》2004,39(10):1459-1465
BACKGROUND: Non-organ-specific autoantibodies are present in centenarians without evidence of autoimmune diseases but conflicting or no data on anti-phospholipid and anti-phospholipid binding proteins were reported. OBJECTIVE: To investigate the presence and antigen specificity of anti-phospholipid and anti-phospholipid binding proteins in centenarians. METHODS: Seventy-seven centenarians, 70 adult controls, 65 unselected elderly subjects, and 38 old SENIEUR volunteers were investigated. Anti-cardiolipin, anti-human beta 2 glycoprotein I, and lupus anticoagulant were detected. Antigen specificity was assayed against plates coated with anionic, neutral and cationic phospholipids and beta 2 glycoprotein I-dependence was also evaluated. RESULTS: 54.3% of the centenarians were positive for IgG and 8.6% for IgM anti-beta 2 glycoprotein I antibodies, while only 20.7% centenarians were positive for anti-cardiolipin IgG and 2.59% for IgM; none resulted positive for lupus anticoagulant. Anti-cardiolipin positive sera cross-reacted with negatively charged phospholipids and displayed decreased binding to serum-free cardiolipin-coated plates that was restored by human beta 2 glycoprotein I or fetal calf serum. CONCLUSIONS: Centenarians display high reactivity against human beta 2 glycoprotein I but low binding to the bovine molecule in the anti-cardiolipin assay. In spite of the presence of antibodies comparable to those found in patients with the anti-phospholipid syndrome, no vascular events were reported suggesting the presence of unknown protective factors and/or the lack of triggering factors. 相似文献
24.
Fragasso G Piatti Md PM Monti L Palloshi A Setola E Puccetti P Calori G Lopaschuk GD Margonato A 《American heart journal》2003,146(5):854
Background
Trimetazidine (TMZ) has been shown to partially inhibit free fatty acid oxidation by shifting substrate utilization from fatty acid to glucose. The aim of this study was to assess the effects of TMZ in patients with diabetes and ischemic cardiomyopathy.Methods
Sixteen patients with diabetes and ischemic hypokinetic cardiomyopathy (all males) on conventional therapy were randomized to receive either placebo or TMZ (20 mg 3 times per day), each arm lasting 15 days, and then again to receive either placebo or TMZ for 2 additional 6-month periods, according to a double-blind, crossover design. At the end of each period, all patients underwent exercise testing, 2-dimensional echocardiography, and hyperinsulinemic/euglycemic clamp. Among the others, New York Heart Association class, ejection fraction, exercise time, fasting blood glucose, end-clamp M value (index of total body glucose disposal) and endothelin-1 levels were evaluated.Results
Both in the short and long term (completed by 13 patients), on TMZ compared to placebo, ejection fraction (47 ± 7 vs 41 ± 9 and 45 ± 8 vs 36 ± 8%, P < .001 for both) and M value (4.0 ± 1.8 vs 3.3 ± 1.6, P = .003, and 3.5 ± 1.5 vs 2.7 ± 1.6 mg/kg body weight/min, P < .01) increased, while fasting blood glucose (121 ± 30 vs 136 ± 40, P = .02 and 125 ± 36 vs 140 ± 43, P = .19) and endothelin-1 (8.8 ± 3.8 vs 10.9 ± 3.8, P < .001 and 6.2 ± 2.4 vs 9.2 ± 4.3 pg/mL, P = .03) decreased. In the short term, 10 patients decreased 1 class on the NYHA scale during treatment with TMZ (P = .019 vs placebo). Eight patients decreased 1 NYHA class while on long-term TMZ treatment, while on placebo 1 patient increased 1 NYHA class and none improved (P = .018 vs placebo).Conclusions
In a short series of patients with diabetes and ischemic cardiomyopathy, TMZ improved left ventricular function, symptoms, glucose metabolism, and endothelial function. Shifting energy substrate preference away from fatty acid metabolism and toward glucose metabolism by TMZ appears an effective adjunctive treatment in patients with diabetes with postischemic cardiomyopathy. 相似文献25.
Piero Olliaro Luciano Lombardi Simona Frigerio Nicoletta Basilico Donatella Taramelli Diego Monti 《Ultrastructural pathology》2013,37(1):9-13
Hemozoin, the detoxification product of hemoglobin heme, piles up as electron-dense material in the food vacuole (FV) of intraerythrocytic malaria parasites (malaria pigment). In infected individuals, pigment is internalized by both circulating and resident phagocytes, thus modulating their functions. Synthetic beta-hematin, prepared in vitro from hematin (ferriprotoporphyrin IX hydroxide) in acidic condition, is spectroscopically identical to hemozoin. In this electron microscopy study, native and synthetic hemozoin also prove to be morphologically indistinguishable (large polygonal crystals with apparent transverse banding) and to undergo the same process when internalized by phagocytes (primarily a direct uptake of crystals, similar to what is described for asbestos fibers). On the contrary,whole parasites appear to follow a classical endocytic pathway. This suggests that there may be differences between the ingestion of free particles and whole parasites in terms of modulation of phagocytes' functions. 相似文献
26.
27.
The role of the Na/K pump for the increased cell energy expenditure in hyperthyroidism was studied by measuring total lymphocyte heat production rate in samples with and without ouabain inhibition of Na/K ATP-ase. In addition, the relative contribution of aerobic processes to lymphocyte thermogenesis was calculated from oxygen consumption measurements. In 12 patients with clinical and laboratory hyperthyroidism total lymphocyte heat production rate was 3.19 +/- 0.21 pW/cell, significantly higher than in 7 patients with subclinical hyperthyroidism (2.14 +/- 0.11 pW/cell) and in 15 euthyroid subjects (2.26 +/- 0.11 pW/cell) (p less than 0.001). The relative decrease in lymphocyte heat production rate after ouabain, giving a quantitative measure of the activity of the Na/K ATP-ase and reflecting the importance of Na/K pump function for the overall rate of lymphocyte metabolism, was not significantly different between the groups: 19.5 +/- 3.6% in hyperthyroid patients, 14.2 +/- 2.3% in subclinical hyperthyroid patients and 17.8 +/- 3.1% in euthyroid subjects. According to the rate of lymphocyte oxygen consumption, aerobic processes represented 58.4 +/- 6.7% of total lymphocyte energy expenditure in hyperthyroid patients, not significantly different from subclinical hyperthyroidism (62.6 +/- 8.4%) or from euthyroidism (66.6 +/- 2.7%). These data do not support the hypothesis of a specific role of the Na/K pump function for the increased cell thermogenesis in hyperthyroidism and indicate a parallel stimulation of aerobic and anaerobic processes by thyroid hormone excess. 相似文献
28.
Zuccotti M Garagna S Merico V Monti M Alberto Redi C 《Molecular and cellular endocrinology》2005,234(1-2):11-17
Although the female gamete is blocked at the dictyate stage of the first meiotic prophase during the whole folliculogenesis, many important epigenetic changes occur to organise the genome to attend early embryonic development. In this paper, we will describe the results of a number of studies aimed to improve our understanding of the nuclear organization of the mouse oocyte during folliculogenesis. Using silver methods that stain NOR, centromeres and heterochromatin, as well as, the use of specific antibodies for the demonstration of centromeres, we have described the changes to the chromatin organisation and to the spatial localisation of chromocenters and centromeres during oocyte growth; these changes have been correlated to the developmental competence of the resulting antral and metaphase II (MII) oocyte. 相似文献
29.
30.
Carlo Marini Bruno Formichi Carolina Bauleo Claudio Michelassi Roberta Pancani Renato Prediletto Massimo Miniati Giosuè Catapano Simonetta Monti Francesca Mannucci Antonio Tavoni Anna D’Ascanio Luigi Emilio Pastormerlo Alberto Giannoni Carlo Giuntini 《Internal and emergency medicine》2014,9(4):385-396
Reportedly, patients with scleroderma-related pulmonary hypertension (SSc-PAH) respond poorly to new vasoactive drugs (NVD). Forty-nine SSc-PAH patients underwent right heart catheterization (RHC) and, according to NVD availability, divided as follows: Group 1 (n = 23, from 1999 to 2004, poor availability), and Group 2 (n = 26, from 2005 to 2010, good availability). Before diagnostic RHC, NVD had been given to 30 % of the patients in Group 1, and 58 % of those in Group 2 (p = 0.049). At diagnosis, patients in Group 1 had greater heart dilatation (p < 0.01), higher mean pulmonary artery pressure (p < 0.05), lower pulmonary artery capacitance (p < 0.05), and lower carbon monoxide lung diffusing capacity (DLco, p < 0.05) than those in Group 2. At a median follow-up time of 15.5 months, DLco further decreased in Group 1 (p < 0.05), whereas cardiac index increased in Group 2 (p < 0.05). At 36 months of follow-up, 72.4 % of the patients in Group 2 were still alive as opposed to 30.4 % in Group 1 (p = 0.02). In multivariate analysis, DLco and mixed venous oxygen saturation (SvO2) were independent predictors of survival. A value of DLco <7.2 mL/mmHg/min was associated with a hazard ratio (HR) of 5.3 (p < 0.001); for SvO2 <63.8 %, the HR was 3.7 (p < 0.01).NVD have beneficial effects in patients with SSc-PAH. Both DLco and SvO2 are predictors of survival and may assist in planning treatment. 相似文献