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71.
PURPOSE: Recent findings indicating that many genes related to cancer development are silenced by an aberrant DNA methylation suggest that inhibitors of this process may be effective cancer therapeutics. In this study we investigated the efficacy of low-dose 5-aza-2'-deoxycitydine (DAC), a methylation inhibitor, with interleukin (IL) 12, one of the most potent cytokines with antitumor activity. Experimental Design: Mice inoculated with L1210 leukemia cells or with B16F10 melanoma cells were treated with 7 daily injections of low-dose DAC (0.2 mg/kg) and/or 7 daily doses of IL-12 (100 ng/dose). Scid/scid mice as well as monoclonal antibodies against CD4, CD8, and NK1.1 were used to investigate the mechanisms of the antitumor effects of the combination treatment. The activity of murine lymphocytes was measured with enzyme-linked immunospot and (51)Cr release assays. RESULTS: Treatment with DAC or IL-12 given alone produced moderate antitumor effects. In both tumor models combined treatment resulted in potentiated antitumor effects and produced 70% long-term survivors among mice inoculated with L1210 cells. The antitumor efficacy of combined treatment was abrogated in scid/scid mice, and after depletion of CD4(+) and CD8(+) T cells. Mice inoculated with B16F10 melanoma cells had significantly delayed tumor growth after combined treatment with DAC and IL-12. Strong antitumor effect correlated with a significant activation of lymph node-derived CD8(+) and CD4(+) cells. Transient neutropenia was observed in mice under treatment of DAC alone, but remarkably this effect was not potentiated by IL-12. CONCLUSIONS: This study provides the first evidence that antitumor effects of DAC can be strongly potentiated by IL-12 and could be beneficial in an effective low-dose-based antitumor therapy.  相似文献   
72.
High cytoplasmic expression of maspin was described in ovarian cancers of shorter survival rates. Until now, no relationship has been described between expression of maspin and sensitivity to cisplatin in ovarian cancers. This study aimed at examining the relationship between expression of maspin, detected by immunohistochemistry and clinical response to cisplatin in ovarian cancer cases as well as the in vitro sensitivity to cisplatin of 11 ovarian cancer cell lines. The analyzes were performed on 73 samples of ovarian cancer and on A2780P, A2780RCIS, CAOV-3, EFO 21, EFO 27, ES-2, Mdah 2774, OAW 42, OVCAR-3, PA-1, and SKOV-3 ovarian cancer cells. Cytoplasmic maspin expression in studied cells significantly correlated with cisplatin sensitivity. A significantly shorter overall survival and progression-free survival was associated with lower cytoplasmic maspin expression at first-look laparotomies and nuclear maspin expression and secondary cytoreductions. Higher nuclear maspin at first-look laparotomies expression was specific for cases of complete response. In the study, the elevated expression of maspin was shown to be typical for cisplatin-sensitive ovarian cancers.  相似文献   
73.
Nogo‐B (Reticulon 4B) is considered to be a novel vascular marker, which may have a protective role in injury‐induced neointima formation and atherosclerosis. Nogo A/B is found to be crucial for monocyte/macrophage recruitment in acute inflammation and it is expressed in CD68 + macrophages. We hypothesize that macrophage infiltration in atherosclerosis is not dependent on Nogo‐B expression in arterial wall. We have assessed Nogo‐B expression and macrophage accumulation in the iliac arteries of healthy organ donors and organ donors with cardiovascular risk factors. Paraffin sections of 66 iliac arteries, from 44 deceased organ donors (17 women and 27 men), were studied. The healthy and cardiovascular risk (CVR) subgroups were created. With regard to staging of the atherosclerotic process, the thickness of arterial intima was measured in digitalized images of H+E stained tissue sections. Immunohistochemical reactions (Nogo‐B and CD68) were carried out in all arteries (66 samples). Western blotting (WB‐19 samples) and real‐time PCR (27 samples) were performed on selected arteries. Significantly higher Nogo‐B expression was demonstrated in the intima of the healthy subjects' subgroup, using immunohistochemistry. WB and real‐time PCR revealed a trend toward lower Nogo‐B expression in the adventitia of the CVR subgroup. Furthermore, the thickness of the intima was found to negatively correlate with the expression of Nogo‐B in the intima and media (r = ?0.32; p < 0.05; r = ?0.32; p < 0.05). Macrophage infiltrates were more prominent in intima of CVR subjects (0.65 vs 3.52 a.u.; p < 0.01). Macrophage density in intima increased with atherosclerosis progression (r = 0.37; p < 0.01). CD68 macrophages density in adventitia was lower in CVR arteries than in healthy arteries. The expression of Nogo‐B, in arterial intima, is impeded in the early stages of atherosclerosis. Accumulation of arterial intimal CD68 macrophages has been shown to progress; however, the overall macrophage density in the adventitia is reduced in arteries shown to have intimal thickening. Macrophage infiltration is not accompanied by Nogo‐B expression in atherosclerotic arteries.  相似文献   
74.
A high-frequency scanning system consisting of a 20-MHz linear array transducer combined with a 20-MHz pulsed Doppler probe was introduced to evaluate the degree of radial artery flow-mediated dilation (FMD [%]) in two groups of patients after 5?min of controlled forearm ischemia followed by reactive hyperemia. In group I, comprising 27 healthy volunteers, FMD (mean?±?standard deviation) was 15.26?±?4.90% (95% confidence interval [CI]: 13.32%–17.20%); in group II, comprising 17 patients with chronic coronary artery disease, FMD was significantly less at 4.53?±?4.11% (95% CI: 2.42%–6.64%). Specifically, the ratio FMD/SR (mean?±?standard deviation), was equal to 5.36?×?10?4?±?4.64?×?10?4 (95% CI: 3.54?×?10?4 to 7.18?×?10?4) in group I and 1.38?×?10?4?±?0.89?×?10?4 (95% CI: 0.70?×?10?4 to 2.06?×?10?4) in group II. Statistically significant differences between the two groups were confirmed by a Wilcoxon–Mann–Whitney test for both FMD and FMD/SR (p?<0.01). Areas under receiver operating characteristic curves for FMD and FMD/SR were greater than 0.9. The results confirm the usefulness of the proposed measurements of radial artery FMD and SR in differentiation of normal patients from those with chronic coronary artery disease.  相似文献   
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Health related quality of life (HRQoL) of living kidney donors on average is good, but some donors experience a low HRQoL after donation. This study assessed the prevalence of reduced HRQoL and explored associations with pre‐ and post‐donation variables. 316 donors (response rate 74%) who donated a kidney between 1997 and 2009 filled in a questionnaire. HRQoL was measured using the Short‐Form 36; fatigue using the Multidimensional Fatigue Inventory; societal participation using the Utrecht Scale for Evaluation of Rehabilitation‐Participation. Donors on average had better HRQoL than the general population. However, 12% had a reduced physical (PCS) and 18% a reduced mental (MCS) HRQoL. Donors with reduced HRQoL reported greater fatigue (P < 0.01), lower societal participation (P < 0.01) and showed a trend towards statistical significance in experiencing more donor–recipient relationship changes (P = 0.07). Prior to donation, donors with reduced PCS had a higher BMI (P < 0.05) and more often smoked (P < 0.05). Donors with reduced MCS had higher expectations (P < 0.05). Reduced HRQoL is associated with higher BMI, smoking and higher expectations prior to donation. These results may be used to develop a screening instrument to select donors at high risk for reduced HRQoL.  相似文献   
79.
J Clin Hypertens (Greenwich). 2012;14:701–710. ©2012 Wiley Periodicals, Inc. The authors aimed to determine the effect of the time of hypotensive drug administration on the progress of degenerative changes within the optic nerve in patients with hypertension and glaucoma. Two groups were included in the study: group A comprised patients-dippers taking drugs in the mornings, and group B comprised patients-nondippers taking drugs both in the mornings and in the evenings. After 6 months, group B showed significant drops in nocturnal diastolic blood pressure (BP) (month 1=73.27 mm Hg vs month 6=67.50 mm Hg), nocturnal mean BP (89.34 vs 84.65 mm Hg), and minimum diastolic BP (50.74 vs 44.03 mm Hg). Group B also showed significant reductions in nocturnal ocular perfusion pressure (43.0 vs 39.73), retinal nerve fiber layer thickness (131.31 vs 113.12 μm), and flow in the eye vessels. Taking hypotensive drugs in the evening may significantly decrease blood flow in the eye arteries, cause degenerative changes within the optic nerves, and result in greater loss in the field of vision.  相似文献   
80.
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