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791.
Leticia Zumoffen Ghiglione Carla Marcelo Signorini Adriana Salvo 《Journal of Applied Entomology》2021,145(8):767-776
Myzus persicae (Sulzer) is a highly polyphagous aphid species that attacks several economically important crop plants. Here, trophic webs involving M. persicae, its host plants and its parasitoids were described and quantified in wheat, oat and alfalfa agroecosystems from central Argentina, with special emphasis on the sub-habitats where interactions occur: crops and adjacent field margins. Three fields cultivated with each crop species and their margins were sampled during three years; aphid abundance and mummification percentage were compared among crop plants and the diverse natural vegetation in the borders. Interactions were described using a quantitative food web approach, and abundance and mummification percentage e data were analysed using a generalized linear model. Four plant species present in the borders (Capsella bursa-pastori, Rapistrum sp., Melilotus sp. and Trifolium repens) hosted M. persicae and its parasitoids. The alfalfa agroecosystem produced a significantly higher number of aphids than oat and wheat; however, in all cases, crops and borders sustained similar aphid abundance. A total of six Aphidiinae species attacked M. persicae, with no significant differences in the richness of parasitoid species between the borders and the crops, but with significant differences in parasitoid abundance, being higher in the crops. Mummification percentage were higher in crops than in the borders, with Lysiphlebus testaceipes, Aphidius colemani and A. ervi being the most abundant species. Almost 70% of M. persicae individuals were collected from fields borders, which highlights the importance of including these sites in studies of trophic interactions in crop fields. 相似文献
792.
González S Maldonado JE Ortega J Talarico AC Bidegaray-Batista L Garcia JE Duarte JM 《Molecular ecology resources》2009,9(3):754-758
The small red brocket deer Mazama bororo is one of the most endangered deer in the Neotropics. The great morphological similarities with three other sympatric brocket deer species, coupled with the fact that they inhabit densely forested habitats complicate detection and prevent the use of traditional methodologies for accurate identification of species. The ability to determine the presence of this endangered species in an area is crucial for estimating its distribution range, and is critical for establishing conservation management strategies. Here we describe a fast and reliable noninvasive genetic method for species identification of Mazama species from faeces. We designed a primer set that amplifies a short 224-bp fragment of the cytochrome b and demonstrate its effectiveness in successful amplification of DNA isolated from both tissue and faecal samples. This fragment contains a BSTNI/ECORII digestion site that is unique to the endangered M. bororo. The digested polymerase chain reaction products yielded a 160-bp fragment that is clearly visible in a 2% agarose gel. Two other diagnostic sites were identified to differentiate the other three sympatric species, SspI (M. gouazoubira) and AflIII (M. americana, and M. nana). 相似文献
793.
Patricia Nessralla Alpoim Melina de Barros Pinheiro Daniela Rezende Garcia Junqueira Leticia Gonçalves Freitas Maria das Graças Carvalho Ana Paula Salles Moura Fernandes Flávia Komatsuzaki Karina Braga Gomes Luci Maria Sant’Ana Dusse 《Molecular biology reports》2013,40(3):2253-2261
Preeclampsia (PE) is a multifactorial pregnancy-specific syndrome which represents one of the leading causes of maternal mortality worldwide. Inherited thrombophilia have been investigated as risk factor for the development of PE and it is currently known that ABO blood group may impact haemostatic balance, having the non-O blood groups (A, B or AB) subjects increased risk for thrombus formation, as compared to those of group O. We performed a systematic review of the literature for published studies investigating whether ABO blood groups could influence PE developing. A sensitive search of four databases identified 45 unique titles. The retrieved papers were assessed independently by authors and a rigorous process of selection and data extract was conduct. Methodological quality of the included studies was also evaluated. Two studies met eligibility criteria. As a main finding of our systematic review, an association between the AB blood group and the occurrence of PE was detected based on two original studies. Considering the role of ABO blood groups on the hemostatic process and thrombus formation, special attention should be given to pregnant patients carrying the AB blood group in order to prevent the syndrome and improve prognosis. 相似文献
794.
Takahashi Juliana Possatto Fernandes Feliciano Leticia Marielle Santos Dayane Cristina Silva Ramos Silézia Oliveira Rogério A. Attili-Angelis Derlene Rodrigues Nadia Regina Sampaio Jorge Luiz Mello dos Anjos Martins Marilena Melhem Marcia Souza Carvalho 《Current fungal infection reports》2020,14(1):9-14
Current Fungal Infection Reports - Acquired resistance among fungal strains is a growing concern. The reasons for the emergence of this phenomenon, with great clinical implications, are only... 相似文献
795.
Elibeth Mirasol-Meléndez Luis G. Brieba Corina Díaz-Quezada Marisol López-Hidalgo Elisa E. Figueroa-Angulo Leticia Ávila-González Rossana Arroyo-Verástegui Claudia G. Benítez-Cardoza 《Parasitology international》2018,67(4):444-453
Trichomonas vaginalis is the protist parasite that causes the most common, non-viral sexually transmitted infection called trichomonosis. Enolase is a moonlighting protein that apart from its canonical function as a glycolytic enzyme, serves as a plasminogen receptor on the cell surface of T. vaginalis and, in consequence, it has been stablished as a virulence factor in this parasite. In the Trichomonas vaginalis sequence database there are nine genes annotated as enolase. In this work, we analyzed these genes as well as their products. We found that seven out of nine genes might indeed perform enolase activity, whereas two genes might have been equivocally identified, or they might be pseudogenes. Furthermore, a combination of qRT-PCR and proteomic approaches was used to assess, for the first time, the expression of these genes in the highly virulent mexican isolate of T. vaginalis CNCD-147 at different iron concentrations. We could find peptides corresponding to enolases encoded by genes TVAG_464170, TVAG_043500 and TVAG_329460. Moreover, we identified two distinctive characteristics within enolases from Trichomonas vaginalis. One of them corresponds to three key substitutions within one of the loops of the active site, compared to host enolase. The other, is a unique N-terminal motif, composed of 15 to 18 residues, on all the potentially active enolases, whose function still has to be stablished. Both differential features merit further studies as potential drug and vaccine targets as well as diagnosis markers. These findings offer new possibilities to fight trichomonosis. 相似文献
796.
Jacek J. Slon-Usakiewicz Andrew Pasternak Neil Reid Leticia M. Toledo-Sherman 《Clinical proteomics》2004,1(3-4):227-234
Methotrexate has been a clinical agent used in cancer, immunosuppression, rheumatoid arthritis, and other highly proliferative
diseases for many years, yet its underlying molecular mechanism of action in these therapeutic areas is still unclear. We
have previously reported using a chemical proteomics technique on several other potential pharmacodynamic targets of methotrexate.
Here, using a frontal affinity chromatography with mass spectrometry detection, we confirm one of these targets, hypoxanthine-guanine
amidophosphoribosyltransferase, as a true binder of methotrexate with a Kd of 4.2 μM. These results complement and confirm our recent study, but more importantly, shed light into the mechanism of action of
methotrexate in oncology and other highly proliferative diseases and may help explain some unaccounted for effects of this
drug. For example, despite the fact that DNA salvage pathway enzymes are highly active, methotrexate can be effective if it
only targets enzymes of the de novo pathway. 相似文献
797.
Juliana Caroline Butzge Christiane Pivotto Leticia Mezzomo Simone Krause Ferrão João Marcelo Astolfi Picanço Adelina Mezzari Luciane Noal Calil Renata Pereira Limberger Miriam A. Apel 《化学与生物多样性》2023,20(10):e202300663
Essential oils (EOs) are products of secondary metabolism with recognized organoleptic characteristics and biological properties. Recently, there has been a growing demand for EOs in the national and international market, mainly due to the recognition of their use as complementary medicine practices, and the increased use in the industries of pharmaceutics, cosmetics, well-being, veterinary and agroecology, boosting the productive sector. In this context, EOs from grasses of the Cymbopogon (Poaceae) are promising sources of bioactive compounds, due to their recognized biological properties, such as anti-inflammatory, antibacterial, antifungal, antidiabetic, repellent, and larvicide. Thus, the present study aims to carry out a review of the scientific literature of the main works related to the evaluation of the antifungal action of essential oils extracted from plants of the Cymbopogon genus, compiling the species that showed the best results and relating them to their main chemical constituents. This review covers the following species: C. citratus, C. flexuosus, C. winterianus, C. martinii, C. nardus, C. giganteus, C. schoenanthus, C. khasans, and C. proximus. Among them, C. citratus was the most assessed, being associated with the vast majority of studies (61.9 %), and it was also the species that showed the best results in terms of MIC. 相似文献
798.
799.
Ricardo Reyes-Chilpa Manuel Jiménez-Estrada Elizabeth Cristóbal-Telésforo Leticia Torres-Colín Miguel Angel Villavicencio Blanca Estela Pérez-Escandón Roberto Mercado-González 《Economic botany》2003,57(1):54-64
Hippocratea excelsa andHippocratea celastroides have therapeutic and insecticide applications in Mexican traditional medicine. The toxicity ofH. excelsa root cortex has been previously demonstrated against the stored grain pest Sitophilus zeamais. To identify the active compounds, several extracts (petroleum ether, CH2Cl2, acetone, methanol, and water) and compounds were obtained from the roots, and tested (1% w/w) with a force-feeding assay againstS. zeamais. AllH. excelsa extracts showed high antifeedant activity, and elicited moderate mortality. The triterpenoid pristimerin and a mixture of sesquiterpene evoninoate alkaloids, isolated from the hexane and methanol extracts, respectively, strongly reduced the insect feeding capacity. Other triterpenoids (friedelin, β-sitosterol, canophyllol) isolated from the hexane extract, and the alditol galactitol obtained from the water extract, were innocuous or its activity was not statistically significant. The organic extracts fromH. celastroides only showed moderate antifeedant activity, while the water extract was innocuous. Galactitol was also obtained from this extract. 相似文献
800.
David Barrera Euclides Avila Guillermo Hernández Isabel Méndez Leticia González Ali Halhali Fernando Larrea Angélica Morales Lorenza Díaz 《Reproductive biology and endocrinology : RB&E》2008,6(1):3