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861.
Topashka-Ancheva M Beltcheva M Metcheva R Rojas JA Rodriguez-De la Fuente AO Gerasimova T Rodríguez-Flores LE Teodorova SE 《Biological trace element research》2012,147(1-3):206-216
The detoxification capacity of the clinoptilolite modification KLS-10-MA used as food additive in small mammals, chronically lead-exposed, was proven for the first time. The modified clinoptilolite was prepared based on natural Bulgarian clinoptilolite deposits. As a powder, it was mechanically mixed at 12.5% concentration with the conventional forage for small rodents. Lead in the form of aqueous solution of Pb(NO(3))(2) was diluted in the drinking water. In the ecotoxicological experiment covering 90 days, imprinting control region laboratory mice were used. They were allocated into four groups: group 1, (control): animals fed with conventional food for small rodents and water; group 2: animals fed with conventional food + clinosorbent KLS-10-MA and water; group 3: animals fed with conventional food and water + Pb(NO(3))(2); and group 4: animals fed with conventional food + KLS-10-MA and water + Pb(NO(3))(2). A group of non-exposed healthy animals was fed with conventional forage mixed with KLS-10-MA to prove eventual toxicity of the sorbent and influence on growth performance. The changes in the chromosome structure, mitotic index, erythrocyte form, erythropoiesis, and body weight gain were recorded. On day 90, the following relations were established: Pb-exposed and clinoptilolite-supplemented mice exhibited 2.3-fold lower chromosome aberrations frequency, 2.5-fold higher mitotic index, and 1.5-fold higher percentage normal erythrocytes 1.3-fold higher body weight compared to Pb-exposed and unsupplemented animals. The obtained data showed that the sorbent is practically non-toxic. The results of the present study encourage a further elaboration of a reliable drug based on the tested substance in the cases of chronic lead intoxication. 相似文献
862.
Wawrik B Mendivelso M Parisi VA Suflita JM Davidova IA Marks CR Van Nostrand JD Liang Y Zhou J Huizinga BJ Strąpoć D Callaghan AV 《FEMS microbiology ecology》2012,81(1):26-42
The bioconversion of coal to methane in the San Juan Basin, New Mexico, was investigated. Production waters were analyzed via enrichment studies, metabolite-profiling, and culture-independent methods. Analysis of 16S rRNA gene sequences indicated the presence of methanogens potentially capable of acetoclastic, hydrogenotrophic, and methylotrophic metabolisms, predominantly belonging to the Methanosarcinales and Methanomicrobiales. Incubations of produced water and coal readily produced methane, but there was no correlation between the thermal maturity and methanogenesis. Coal methanogenesis was greater when samples with a greater richness of Firmicutes were utilized. A greater archaeal diversity was observed in the presence of several aromatic and short-chain fatty acid metabolites. Incubations amended with lactate, hydrogen, formate, and short-chain alcohols produced methane above un-amended controls. Methanogenesis from acetate was not observed. Metabolite profiling showed the widespread occurrence of putative aromatic ring intermediates including benzoate, toluic acids, phthalic acids, and cresols. The detection of saturated and unsaturated alkylsuccinic acids indicated n-alkane and cyclic alkane/alkene metabolism. Microarray analysis complemented observations based on hybridization to functional genes related to the anaerobic metabolism of aromatic and aliphatic substrates. These data suggest that coal methanogenesis is unlikely to be limited by methanogen biomass, but rather the activation and degradation of coal constituents. 相似文献
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864.
865.
Reference genome sequence of the model plant Setaria 总被引:16,自引:0,他引:16
Bennetzen JL Schmutz J Wang H Percifield R Hawkins J Pontaroli AC Estep M Feng L Vaughn JN Grimwood J Jenkins J Barry K Lindquist E Hellsten U Deshpande S Wang X Wu X Mitros T Triplett J Yang X Ye CY Mauro-Herrera M Wang L Li P Sharma M Sharma R Ronald PC Panaud O Kellogg EA Brutnell TP Doust AN Tuskan GA Rokhsar D Devos KM 《Nature biotechnology》2012,30(6):555-561
We generated a high-quality reference genome sequence for foxtail millet (Setaria italica). The ~400-Mb assembly covers ~80% of the genome and >95% of the gene space. The assembly was anchored to a 992-locus genetic map and was annotated by comparison with >1.3 million expressed sequence tag reads. We produced more than 580 million RNA-Seq reads to facilitate expression analyses. We also sequenced Setaria viridis, the ancestral wild relative of S. italica, and identified regions of differential single-nucleotide polymorphism density, distribution of transposable elements, small RNA content, chromosomal rearrangement and segregation distortion. The genus Setaria includes natural and cultivated species that demonstrate a wide capacity for adaptation. The genetic basis of this adaptation was investigated by comparing five sequenced grass genomes. We also used the diploid Setaria genome to evaluate the ongoing genome assembly of a related polyploid, switchgrass (Panicum virgatum). 相似文献
866.
867.
David E. Goertz Margarita Todorova Omid Mortazavi Vlad Agache Branson Chen Raffi Karshafian Kullervo Hynynen 《PloS one》2012,7(12)
Ultrasound stimulated microbubbles (USMB) are being investigated for their potential to promote the uptake of anticancer agents into tumor tissue by exploiting their ability to enhance microvascular permeability. At sufficiently high ultrasound transmit amplitudes it has also recently been shown that USMB treatments can, on their own, induce vascular damage, shutdown blood flow, and inhibit tumor growth. The objective of this study is to examine the antitumor effects of ‘antivascular’ USMB treatments in conjunction with chemotherapy, which differs from previous work which has sought to enhance drug uptake with USMBs by increasing vascular permeability. Conceptually this is a strategy similar to combining vascular disrupting agents with a chemotherapy, and we have selected the taxane docetaxel (Taxotere) for evaluating this approach as it has previously been shown to have potent antitumor effects when combined with small molecule vascular disrupting agents. Experiments were conducted on PC3 tumors implanted in athymic mice. USMB treatments were performed at a frequency of 1 MHz employing sequences of 50 ms bursts (0.00024 duty cycle) at 1.65 MPa. USMB treatments were administered on a weekly basis for 4 weeks with docetaxel (DTX) being given intravenously at a dose level of 5 mg/kg. The USMB treatments, either alone or in combination with DTX, induced an acute reduction in tumor perfusion which was accompanied at the 24 hour point by significantly enhanced necrosis and apoptosis. Longitudinal experiments showed a modest prolongation in survival but no significant growth inhibition occurred in DTX–only and USMB-only treatment groups relative to control tumors. The combined USMB-DTX treatment group produced tumor shrinkage in weeks 4–6, and significant growth inhibition and survival prolongation relative to the control (p<0.001), USMB-only (p<0.01) and DTX-only treatment groups (p<0.01). These results suggest the potential of enhancing the antitumor activity of docetaxel by combining it with antivascular USMB effects. 相似文献
868.
The replication machinery of bacteriophage Φ29 is a paradigm for protein-primed replication and it holds great potential for applied purposes. To better understand the early replication events and to find improved origins for DNA amplification based on the Φ29 system, we have studied the end-structure of a double-stranded DNA replication origin. We have observed that the strength of the origin is determined by a combination of factors. The strongest origin (30-fold respect to wt) has the sequence CCC at the 3′ end of the template strand, AAA at the 5′ end of the non-template strand and 6 nucleotides as optimal unpairing at the end of the origin. We also show that the presence of a correctly positioned displaced strand is important because origins with 5′ or 3′ ssDNA regions have very low activity. Most of the effect of the improved origins takes place at the passage between the terminal protein-primed and the DNA-primed modes of replication by the DNA polymerase suggesting the existence of a thermodynamic barrier at that point. We suggest that the template and non-template strands of the origin and the TP/DNA polymerase complex form series of interactions that control the critical start of terminal protein-primed replication. 相似文献
869.
870.
Verónica Gracia-Ibáñez Margarita Vergara James H. Buffi Wendy M. Murray Joaquín L. Sancho-Bru 《Computer methods in biomechanics and biomedical engineering》2017,20(6):587-597
Motion capture of all degrees of freedom of the hand collected during performance of daily living activities remains challenging. Instrumented gloves are an attractive option because of their higher ease of use. However, subject-specific calibration of gloves is lengthy and has limitations for individuals with disabilities. Here, a calibration procedure is presented, consisting in the recording of just a simple hand position so as to allow capture of the kinematics of 16 hand joints during daily life activities even in case of severe injured hands. ‘across-subject gains’ were obtained by averaging the gains obtained from a detailed subject-specific calibration involving 44 registrations that was repeated three times on multiple days to 6 subjects. In additional 4 subjects, joint angles that resulted from applying the ‘across-subject calibration’ or the subject-specific calibration were compared. Global errors associated with the ‘across-subject calibration’ relative to the detailed, subject-specific protocol were small (bias: 0.49°; precision: 4.45°) and comparable to those that resulted from repeating the detailed protocol with the same subject on multiple days (0.36°; 3.50°). Furthermore, in one subject, performance of the ‘across-subject calibration’ was directly compared to another fast calibration method, expressed relative to a videogrammetric protocol as a gold-standard, yielding better results. 相似文献