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51.
L Pereira R Zamudio G Soares-Souza P Herrera L Cabrera CC Hooper J Cok JM Combe G Vargas WA Prado S Schneider F Kehdy MR Rodrigues SJ Chanock DE Berg RH Gilman E Tarazona-Santos 《PloS one》2012,7(8):e41200
Gastric cancer is one of the most lethal types of cancer and its incidence varies worldwide, with the Andean region of South America showing high incidence rates. We evaluated the genetic structure of the population from Lima (Peru) and performed a case-control genetic association study to test the contribution of African, European, or Native American ancestry to risk for gastric cancer, controlling for the effect of non-genetic factors. A wide set of socioeconomic, dietary, and clinic information was collected for each participant in the study and ancestry was estimated based on 103 ancestry informative markers. Although the urban population from Lima is usually considered as mestizo (i.e., admixed from Africans, Europeans, and Native Americans), we observed a high fraction of Native American ancestry (78.4% for the cases and 74.6% for the controls) and a very low African ancestry (<5%). We determined that higher Native American individual ancestry is associated with gastric cancer, but socioeconomic factors associated both with gastric cancer and Native American ethnicity account for this association. Therefore, the high incidence of gastric cancer in Peru does not seem to be related to susceptibility alleles common in this population. Instead, our result suggests a predominant role for ethnic-associated socioeconomic factors and disparities in access to health services. Since Native Americans are a neglected group in genomic studies, we suggest that the population from Lima and other large cities from Western South America with high Native American ancestry background may be convenient targets for epidemiological studies focused on this ethnic group. 相似文献
52.
Zehava Grossman Jonathan M. Schapiro Itzchak Levy Daniel Elbirt Michal Chowers Klaris Riesenberg Karen Olstein-Pops Eduardo Shahar Valery Istomin Ilan Asher Bat-Sheva Gottessman Yonat Shemer Hila Elinav Gamal Hassoun Shira Rosenberg Diana Averbuch Keren Machleb-Guri Zipi Kra-Oz Sara Radian-Sade Hagit Rudich Daniela Ram Shlomo Maayan Nancy Agmon-Levin Zev Sthoeger 《PloS one》2014,9(1)
Background
Analysis of potentially different impact of Lopinavir/Ritonavir (LPV/r) on non-B subtypes is confounded by dissimilarities in the conditions existing in different countries. We retrospectively compared its impact on populations infected with subtypes B and C in Israel, where patients infected with different subtypes receive the same treatment.Methods
Clinical and demographic data were reported by physicians. Resistance was tested after treatment failure. Statistical analyses were conducted using SPSS.Results
607 LPV/r treated patients (365 male) were included. 139 had HIV subtype B, 391 C, and 77 other subtypes. At study end 429 (71%) were receiving LPV/r. No significant differences in PI treatment history and in median viral-load (VL) at treatment initiation and termination existed between subtypes. MSM discontinued LPV/r more often than others even when the virologic outcome was good (p = 0.001). VL was below detection level in 81% of patients for whom LPV/r was first PI and in 67% when it was second (P = 0.001). Median VL decrease from baseline was 1.9±0.1 logs and was not significantly associated with subtype. Median CD4 increase was: 162 and 92cells/µl, respectively, for patients receiving LPV/r as first and second PI (P = 0.001), and 175 and 98, respectively, for subtypes B and C (P<0.001). Only 52 (22%) of 237 patients genotyped while under LPV/r were fully resistant to the drug; 12(5%) were partially resistant. In48%, population sequencing did not reveal resistance to any drug notwithstanding the virologic failure. No difference was found in the rates of resistance development between B and C (p = 0.16).Conclusions
Treatment with LPV/r appeared efficient and tolerable in both subtypes, B and C, but CD4 recovery was significantly better in virologically suppressed subtype-B patients. In both subtypes, LPV/r was more beneficial when given as first PI. Mostly, reasons other than resistance development caused discontinuation of treatment. 相似文献53.
54.
Eduardo Massad Annelies Wilder-Smith Raphael Ximenes Marcos Amaku Luis Fernandez Lopez Francisco Antonio Bezerra Coutinho Giovanini Evelim Coelho Jarbas Barbosa da Silva Jr Claudio José Struchiner Marcelo Nascimento Burattini 《Memórias do Instituto Oswaldo Cruz》2014,109(3):394-397
Brazil will host the FIFA World Cup™, the biggest single-event competition in the
world, from June 12-July 13 2014 in 12 cities. This event will draw an estimated
600,000 international visitors. Brazil is endemic for dengue. Hence, attendees of the
2014 event are theoretically at risk for dengue. We calculated the risk of dengue
acquisition to non-immune international travellers to Brazil, depending on the
football match schedules, considering locations and dates of such matches for June
and July 2014. We estimated the average per-capita risk and expected
number of dengue cases for each host-city and each game schedule chosen based on
reported dengue cases to the Brazilian Ministry of Health for the period between
2010-2013. On the average, the expected number of cases among the 600,000 foreigner
tourists during the World Cup is 33, varying from 3-59. Such risk estimates will not
only benefit individual travellers for adequate pre-travel preparations, but also
provide valuable information for public health professionals and policy makers
worldwide. Furthermore, estimates of dengue cases in international travellers during
the World Cup can help to anticipate the theoretical risk for exportation of dengue
into currently non-infected areas. 相似文献
55.
56.
Selective Cytotoxicity of 1,3,4-Thiadiazolium Mesoionic Derivatives on Hepatocarcinoma Cells (HepG2)
Gustavo Jabor Gozzi Amanda do Rocio Andrade Pires Glaucio Valdameri Maria Eliane Merlin Rocha Glaucia Regina Martinez Guilhermina Rodrigues Noleto Alexandra Acco Carlos Eduardo Alves de Souza Aurea Echevarria Camilla Moretto dos Reis Attilio Di Pietro Sílvia Maria Suter Correia Cadena 《PloS one》2015,10(6)
In this work, we evaluated the cytotoxicity of mesoionic 4-phenyl-5-(2-Y, 4-X or 4-X-cinnamoyl)-1,3,4-thiadiazolium-2-phenylamine chloride derivatives (MI-J: X=OH, Y=H; MI-D: X=NO2, Y=H; MI-4F: X=F, Y=H; MI-2,4diF: X=Y=F) on human hepatocellular carcinoma (HepG2), and non-tumor cells (rat hepatocytes) for comparison. MI-J, M-4F and MI-2,4diF reduced HepG2 viability by ~ 50% at 25 μM after 24-h treatment, whereas MI-D required a 50 μM concentration, as shown by 3-(4,5-dimethythiazol-2-yl)-2,5-diphenyltetrazolium bromide assays. The cytotoxicity was confirmed with lactate dehydrogenase assay, of which activity was increased by 55, 24 and 16% for MI-J, MI-4F and MI-2,4diF respectively (at 25 μM after 24 h). To identify the death pathway related to cytotoxicity, the HepG2 cells treated by mesoionic compounds were labeled with both annexin V and PI, and analyzed by flow cytometry. All compounds increased the number of doubly-stained cells at 25 μM after 24 h: by 76% for MI-J, 25% for MI-4F and MI-2,4diF, and 11% for MI-D. It was also verified that increased DNA fragmentation occurred upon MI-J, MI-4F and MI-2,4diF treatments (by 12%, 9% and 8%, respectively, at 25 μM after 24 h). These compounds were only weakly, or not at all, transported by the main multidrug transporters, P-glycoprotein, ABCG2 and MRP1, and were able to slightly inhibit their drug-transport activity. It may be concluded that 1,3,4-thiadiazolium compounds, especially the hydroxy derivative MI-J, constitute promising candidates for future investigations on in-vivo treatment of hepatocellular carcinoma. 相似文献
57.
58.
59.
Dung Beetle and Terrestrial Mammal Diversity in Forests, Indigenous Agroforestry Systems and Plantain Monocultures in Talamanca, Costa Rica 总被引:2,自引:0,他引:2
In order to explore the importance of indigenous agroforestry systems for biodiversity conservation, we compared the abundance,
species richness and diversity of dung beetles and terrestrial mammals across a gradient of different land use types from
agricultural monocultures (plantains) to agroforestry systems (cocoa and banana) and forests in the BriBri and Cabécar indigenous
reserves in Talamanca, Costa Rica. A total of 132,460 dung beetles of 52 species and 913 tracks of 27 terrestrial mammal species
were registered. Dung beetle species richness and diversity were greatest in the forests, intermediate in the agroforestry
systems and lowest in the plantain monocultures, while dung beetle abundance was greatest in the plantain monocultures. The
number of mammal tracks per plot was significantly higher in forests than in plantain monocultures, whereas mammal species
richness was higher in forests than in either cocoa agroforestry systems or plantain monocultures. Species composition of
both terrestrial mammals and dung beetles also varied across the different land use types. Our study indicates that indigenous
cocoa and banana agroforestry systems maintain an intermediate level of biodiversity (which is less than that of the original
forest but significantly greater than that of plantain monocultures) and provide suitable habitat for a number of forest-dependent
species. Although the agroforestry systems appear to serve as favorable habitats for many terrestrial mammal species, their
potential positive contribution to mammal conservation is being offset by heavy hunting pressure in the reserves. As in other
agricultural landscapes, the conservation of biodiversity in Talamanca will depend not only on maintaining the existing forest
patches and reducing the conversion of traditional agroforestry systems to monocultures, but also on reducing hunting pressure. 相似文献
60.
María Lorena Falcone Ferreyra Eduardo Rodriguez María Isabel Casas Guillermo Labadie Erich Grotewold Paula Casati 《The Journal of biological chemistry》2013,288(44):31678-31688
Flavonoids accumulate in plant vacuoles usually as O-glycosylated derivatives, but several species can also synthesize flavonoid C-glycosides. Recently, we demonstrated that a flavanone 2-hydroxylase (ZmF2H1, CYP93G5) converts flavanones to the corresponding 2-hydroxy derivatives, which are expected to serve as substrates for C-glycosylation. Here, we isolated a cDNA encoding a UDP-dependent glycosyltransferase (UGT708A6), and its activity was characterized by in vitro and in vivo bioconversion assays. In vitro assays using 2-hydroxyflavanones as substrates and in vivo activity assays in yeast co-expressing ZmF2H1 and UGT708A6 show the formation of the flavones C-glycosides. UGT708A6 can also O-glycosylate flavanones in bioconversion assays in Escherichia coli as well as by in vitro assays with the purified recombinant protein. Thus, UGT708A6 is a bifunctional glycosyltransferase that can produce both C- and O-glycosidated flavonoids, a property not previously described for any other glycosyltransferase. 相似文献