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Costa-Lotufo LV Khan MT Ather A Wilke DV Jimenez PC Pessoa C de Moraes ME de Moraes MO 《Journal of ethnopharmacology》2005,99(1):21-30
The present study evaluated the anticancer potential of 11 plants used in Bangladeshi folk medicine. The extracts were tested for cytotoxicity using the brine shrimp lethality assay, sea urchin eggs assay, hemolysis assay and MTT assay using tumor cell lines. The extract of Oroxylum indicum showed the highest toxicity on all tumor cell lines tested, with an IC(50) of 19.6 microg/ml for CEM, 14.2 microg/ml for HL-60, 17.2 microg/ml for B-16 and 32.5 microg/ml for HCT-8. On the sea urchin eggs, it inhibited the progression of cell cycle since the frist cleavage (IC(50)=13.5 microg/ml). The extract of Aegle marmelos exhibited toxicity on all used assays, but in a lower potency than Oroxylum indicum. In conclusion, among all tested extracts, only the extracts of Oroxylum indicum, Moringa oleifera and Aegles marmelos could be considered as potential sources of anticancer compounds. Further studies are necessary for chemical characterization of the active principles and more extensive biological evaluations. 相似文献
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de Sandes Freitas TV Harada KM Felipe CR Galante NZ Sampaio EL Ikehara E Alfieri F Tedesco-Silva Júnior H Medina-Pestana JO 《International urology and nephrology》2011,43(4):1221-1228
Background
Calcineurin inhibitor (CNI) and steroid (ST) withdrawal are strategies under investigation to reduce long-term toxicities associated with current immunosuppressive regimens. We conducted a single center, prospective trial comparing the efficacy and safety of CNI or ST withdrawal in kidney transplant recipients receiving sirolimus-based immunosuppressive regimen. 相似文献105.
Dasgupta A Veras E 《Clinica chimica acta; international journal of clinical chemistry》2006,367(1-2):144-149
BACKGROUND: Ginsengs are used by the general population worldwide and toxicity of various ginsengs has been reported. We studied the effectiveness of activated charcoal and in vitro equilibrium dialysis for removal of Asian, American, Siberian and Indian ginseng from human serum by measuring digoxin-like immunoreactivity using the fluorescence polarization immunoassay. METHODS: 1xPBS (phosphate buffered saline) or drug free serum pool was supplemented with Asian, American, Siberian or Indian ginseng extract in amount expected in overdose. The aliquots of supplemented buffer or serum pool were treated with activated charcoal (15 or 50 mg of activated charcoal/ml of buffer/serum) for 5, 10, 20 and 30 min and digoxin-like immunoreactivities were compared with the original specimens. Other drug free serum pools were also supplemented with various ginsengs and then passed through a small column packed with activated charcoal or subjected to in vitro equilibrium dialysis against phosphate buffer at pH 7.4. RESULTS: Complete removal of digoxin-like immunoreactivity from buffer solution or serum pool supplemented with various ginsengs can be achieved by treatment with activated charcoal. Moreover, when serum pools supplemented with various ginsengs were passed through columns packed with activated charcoal, we observed complete removal of digoxin-like immunoreactivity. In addition, significant removal of digoxin-like immunoreactivity was observed when serum pools supplemented with ginsengs were subjected to equilibrium dialysis for 24 h. CONCLUSIONS: Removal of digoxin-like immunoreactivity from buffer solution or serum due to the presence of ginsengs can be achieved by treatment with activated charcoal in vitro but complete removal of digoxin-like activity from serum is not possible even after 24 h of equilibrium dialysis. 相似文献
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OBJECTIVE:
Due to their toxicity, diesel emissions have been submitted to progressively more restrictive regulations in developed countries. However, in Brazil, the implementation of the Cleaner Diesel Technologies policy (Euro IV standards for vehicles produced in 2009 and low-sulfur diesel with 50 ppm of sulfur) was postponed until 2012 without a comprehensive analysis of the effect of this delay on public health parameters. We aimed to evaluate the impact of the delay in implementing the Cleaner Diesel Technologies policy on health indicators and monetary health costs in Brazil.METHODS:
The primary estimator of exposure to air pollution was the concentration of ambient fine particulate matter (particles with aerodynamic diameters <2.5 µm, [PM2.5]). This parameter was measured daily in six Brazilian metropolitan areas during 2007-2008. We calculated 1) the projected reduction in the PM2.5 that would have been achieved if the Euro IV standards had been implemented in 2009 and 2) the expected reduction after implementation in 2012. The difference between these two time curves was transformed into health outcomes using previous dose-response curves. The economic valuation was performed based on the DALY (disability-adjusted life years) method.RESULTS:
The delay in implementing the Cleaner Diesel Technologies policy will result in an estimated excess of 13,984 deaths up to 2040. Health expenditures are projected to be increased by nearly US$ 11.5 billion for the same period.CONCLUSIONS:
The present results indicate that a significant health burden will occur because of the postponement in implementing the Cleaner Diesel Technologies policy. These results also reinforce the concept that health effects must be considered when revising fuel and emission policies. 相似文献109.
Lo Rito M Leon-Wyss J Veras O Vides I Najera C Castañeda AR 《The Annals of thoracic surgery》2011,(1):366-368
Infective endocarditis in patients with ventricular septal defects can prove life threatening due to acute heart failure or septic embolization. Persistent postoperative risk is bacterial colonization of prosthetic material. We designed the Antibiotic Sandwich Patch to reduce this risk, using a double layer of autologous pericardium containing antibiotic powder. Five patients were managed with this technique for closure of ventricular septal defects complicated by acute infective endocarditis. No colonization of the patches occurred after a median follow up of 1.5 years. This technique reduced the risk of bacterial colonization of the antibiotic sandwich patch, offering an additional surgical option. 相似文献
110.
Natural killer cell precursors in the CD44neg/dim T-cell receptor population of mouse bone marrow 总被引:1,自引:0,他引:1
Natural killer (NK) cells develop from the nonadherent cell component of NK long-term bone marrow (BM) cultures (NK-LTBMC). Because these nonadherent cells are depleted of mature NK cells and T cells, but appear to enriched for NK precursors, they were used as a starting population to begin to define the NK precursors that function in NK- LTBMC. As the stromal cell component of NK-LTBMC has been shown to support interleukin (IL)-2-induced, CD44 dependent, NK cell development from nonadherent NK precursors, NK-LTBMC stroma was used in a limiting dilution assay (LDA) to quantitate the precursors. NK-LTBMC in 96-well plates were irradiated (20 Gy) to kill hematopoietic cells (including the NK precursors), seeded with limiting dilutions of the cells to be quantitated, cultured with 500 U/mL IL-2 for 13 days and assayed for development of NK activity by adding 51Cr-labeled YAC-1 cells to the wells and evaluating the release of 51Cr after 4 hours. Flow cytometric analysis, sorting, and quantitation of the nonadherent cell component of NK-LTBMC showed that NK precursors were concentrated in the CD44neg/dim subset that comprised 10% of the "lymphoid" gated cells. When the CD44neg/dim subset was sorted from BM of mice treated with 5- fluorouracil (5-FU) day before (-1FUBM), there were about 30% T cells, but no NK-1.1+ cells. When the T cells were removed by sorting and the CD44neg/dim, alphabeta, gammadelta T-cell receptorneg (TCR-) subpopulation was seeded onto irradiated stroma with IL-2, they proliferated, developed NK activity, became NK-1.1+ and CD44bright and remained alphabeta, gammadelta TCR-. The frequency of NK precursors in this population as estimated from the LDA was about 1/500. 相似文献