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31.
32.
Adriana Silva-Iturriza Jafet M. Nassar Ariany M. García-Rawlins Romel Rosales Alfredo Mijares 《Parasitology international》2013,62(2):95-99
Trypanosoma evansi is a mammal generalist protozoon which causes negative effects on health and productivity in bovine and equine herds in South America, Europe, Asia and Africa. By molecular methods, we screened the presence of that parasite together with other trypanosome species in 105 bats of 10 species collected in arid zones of northern Venezuela. The first molecular approach was fluorescent fragment length barcoding (FFLB), which relies on amplification of relative small regions of rRNA genes (four loci) and fluorescence detection. By FFLB, 17 samples showed patterns of possible trypanosomatid infections. These samples were used to test presence of trypanosomes by PCR using the following DNA markers: V7–V8 SSU rRNA, gGAPDH and kDNA minicircle regions. Only in one individual of the nectar-feeding bat, Leptonycteris curasoae, we were able to amplify 1000 bp of the trypanosome kDNA minicircle. That PCR product was sequenced and the parasite species was determined by NCBI-BLAST and phylogenetic analysis. Both analyses showed that the minicircle sequence corresponds to Trypanosoma evansi. The phylogenetic analysis of the sequence obtained in this study clustered with a T. evansi sequence obtained in a Venezuelan capybara, Hydrochoerus hydrochaeris, and distant of others two T. evansi sequences obtained in a Colombian capybara and horse. This result supports the hypothesis of multiple origins of T. evansi in South America. 相似文献
33.
Anita K. Gandhi Tao Shi Mingyu Li Ulf Jungnelius Alfredo Romano Josep Tabernero Salvatore Siena Peter H. Schafer Rajesh Chopra 《PloS one》2013,8(11)
This study assessed the immunomodulatory effects in previously treated KRAS-mutant metastatic colorectal cancer patients participating in a phase II multicenter, open-label clinical trial receiving lenalidomide alone or lenalidomide plus cetuximab. The main findings show the T cell immunostimulatory properties of lenalidomide as the drug induced a decrease in the percentage CD45RA+ naïve T cells 3-fold while increasing the percentage HLA-DR+ activated T helper cells and percentage total CD45RO+ CD8+ memory T cytotoxic cells, 2.6- and 2.1-fold respectively (p<0.0001). In addition, lenalidomide decreased the percentage of circulating CD19+ B cells 2.6-fold (p<0.0001). Lenalidomide increased a modest, yet significant, 1.4-fold change in the percentage of circulating natural killer cells. Our findings indicate that lenalidomide significantly activates T cells, suggestive of an immunotherapeutic role for this drug in settings of maintenance therapy and tumor immunity. Furthermore, reported for the first time is the effect of lenalidomide in combination with cetuximab on T cell function, including increases in circulating naïve and central memory T cells. In summary, lenalidomide and cetuximab have significant effects on circulating immune cells in patients with colorectal carcinoma.
Trial Registration
ClinicalTrials.gov NCT01032291相似文献34.
Alfredo Tlahuice-Flores 《Journal of molecular modeling》2013,19(4):1937-1942
The study reported herein addressed the structure, adsorption energy and normal modes of zwitterion l-cysteine (Z-cys) adsorbed on the Au20 cluster by using density functional theory (DFT). It was found that four Z-cys are bound to the Au20 apexes preferentially through S atoms. Regarding normal modes, after adsorption of four Z-cys molecules, a more intense infrared (IR) peak is maintained around 1,631.4 cm?1 corresponding with a C=O stretching mode, but its intensity is enhanced approximately six times. The enhancement in the intensity of modes between 0 to 300 cm?1 is around 4.5 to 5.0 times for normal modes that involve O–C=O and C-S bending modes. Other two normal modes in the range from 300 to 3,500 cm?1 show enhancements of 6.0 and 7.4 times. In general, four peaks show major intensities and they are related with normal modes of carboxyl and NH3 groups of Z-cys. 相似文献
35.
Evan J. Molinelli Anil Korkut Weiqing Wang Martin L. Miller Nicholas P. Gauthier Xiaohong Jing Poorvi Kaushik Qin He Gordon Mills David B. Solit Christine A. Pratilas Martin Weigt Alfredo Braunstein Andrea Pagnani Riccardo Zecchina Chris Sander 《PLoS computational biology》2013,9(12)
We present a powerful experimental-computational technology for inferring network models that predict the response of cells to perturbations, and that may be useful in the design of combinatorial therapy against cancer. The experiments are systematic series of perturbations of cancer cell lines by targeted drugs, singly or in combination. The response to perturbation is quantified in terms of relative changes in the measured levels of proteins, phospho-proteins and cellular phenotypes such as viability. Computational network models are derived de novo, i.e., without prior knowledge of signaling pathways, and are based on simple non-linear differential equations. The prohibitively large solution space of all possible network models is explored efficiently using a probabilistic algorithm, Belief Propagation (BP), which is three orders of magnitude faster than standard Monte Carlo methods. Explicit executable models are derived for a set of perturbation experiments in SKMEL-133 melanoma cell lines, which are resistant to the therapeutically important inhibitor of RAF kinase. The resulting network models reproduce and extend known pathway biology. They empower potential discoveries of new molecular interactions and predict efficacious novel drug perturbations, such as the inhibition of PLK1, which is verified experimentally. This technology is suitable for application to larger systems in diverse areas of molecular biology. 相似文献
36.
37.
Ordiano-Flores Alfredo Galván-Magaña Felipe Sánchez-González Alberto Páez-Osuna Federico 《Biological trace element research》2020,195(1):215-225
Biological Trace Element Research - We report cadmium (Cd) concentrations in muscle, liver, and blood of striped marlin (Kajikia audax) and blue marlin (Makaira nigricans), caught in the southwest... 相似文献
38.
Polito Francesca Famà Fausto Oteri Rosaria Raffa Giovanni Vita Gianluca Conti Alfredo Daniele Sacco Macaione Vincenzo Passalacqua Marcello Cardali Salvatore Di Giorgio Rosa Maria Gioffrè Maria Angileri Flavio F. Germanò Antonino Aguennouz M’Hammed 《Molecular biology reports》2020,47(4):2941-2949
Molecular Biology Reports - TBI is the main cause of death and disability in individuals aged 1–45 in Western countries. One of the main challenges of TBI at present is the lack of specific... 相似文献
39.
Javier Hernán Rojo Daniel Alfredo Fernández Daniel Enrique Figueroa Claudia Clementina Boy 《Journal of fish biology》2020,96(4):956-967
This study reports the phenotypic and genetic differences between individuals of puyen Galaxias maculatus from two sites in the same river basin in Tierra del Fuego National Park, southern South America. Individuals from the two sampling sites presented morphometric and genetic differences. The morphometric differences indicated that individuals from Laguna Negra (LN) were short and more robust and had large eyes, whereas those from Arroyo Negro (AN) were thin and elongated and had small eyes. Genetic differences showed that AN individuals had a greater genetic structuration and an older demographic history than LN individuals. The results of this study affirmed that the individuals from the two sampling sites belong to different populations with a high degree of isolation. The demographic history could indicate that the individuals of G. maculatus which migrated to northern areas during the last glaciation settled in the Beagle Channel after its formation. The LN population could have originated after the retreat of the glaciers, migrating from AN. 相似文献
40.
Alejandro Carmona Eva Friero Alfredo de Bustos Nicolás Jouve Angeles Cuadrado 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2013,126(4):949-961
Non-denaturing FISH (ND-FISH) was used to compare the distribution of four simple sequence repeats (SSRs)—(AG) n , (AAG) n , (ACT) n and (ATC) n —in somatic root tip metaphase spreads of 12 barley (H. vulgare ssp. vulgare) cultivars, seven lines of their wild progenitor H. vulgare ssp. spontaneum, and four lines of their close relative H. bulbosum, to determine whether the range of molecular diversity shown by these highly polymorphic sequences is reflected at the chromosome level. In both, the cultivated and wild barleys, clusters of AG and ATC repeats were invariant. In contrast, clusters of AAG and ACT showed polymorphism. Karyotypes were prepared after the identification of their seven pairs of homologous chromosomes. Variation between these homologues was only observed in one wild accession that showed the segregation of a reciprocal translocation involving chromosomes 5H and 7H. The two subspecies of H. vulgare analysed were no different in terms of their SSRs. Only AAG repeats were found clustered strongly on the chromosomes of all lines of H. bulbosum examined. Wide variation was seen between homologous chromosomes within and across these lines. These results are the first to provide insight into the cytogenetic diversity of SSRs in barley and its closest relatives. Differences in the abundance and distribution of each SSR analysed, between H. vulgare and H. bulbosum, suggest that these species do not share the same H genome, and support the idea that these species are not very closely related. Southern blotting experiments revealed the complex organization of these SSRs, supporting the findings made with ND-FISH. 相似文献