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Barreto da Silveira Ismênia Glauce de Oliveira da Silva Neto Jorge Alves da Silva Ferreira Jéssica Silva Tatiane Severo Holanda Ioná Santos Araújo 《Molecular biology reports》2021,48(10):6887-6895
Molecular Biology Reports - Leprosy is a chronic infectious disease caused by Mycobacterium leprae and persists as a serious public health problem in Brazil. This microorganism is inculturable,... 相似文献
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Agna R.S. Rodrigues Jorge B. Torres Herbert A.A. Siqueira Daniel P.A. Lacerda 《Biological Control》2013,64(3):217-224
Lambda-cyhalothrin is a pyrethroid insecticide widely used to control pests in various crop ecosystems, in which the lady beetle occurs naturally. Therefore, lady beetle populations are exposed to lambda-cyhalothrin sprays that may foster tolerance to this insecticide. This study was conducted to confirm the occurrence of resistance in the lady beetle Eriopis connexa (Germar) (Coleoptera: Coccinellidae) to lambda-cyhalothrin and to characterize the inheritance of resistance after eight progressive selection with insecticide dosages based on the LD50 determined for the F1 generation. Dose–mortality curves were determined for parental populations, F1 hybrids and backcross progenies. Parameters regarding the heritability of resistance to lambda-cyhalothrin in E. connexa allow estimating 10-fold increase in the initial LD50 after 54.5 generations of successive selections. The resistance of E. connexa to lambda-cyhalothrin was characterized as autosomally inherited and incompletely dominant, and influenced by a major gene with possible influence of secondary genes. Additionally, the resistance in E. connexa varies from functionally dominant to functionally recessive depending on the dose used. These findings indicate that insecticide resistance in E. connexa can be selected in the field as determined for field-collected individuals, and subsequently enhanced under laboratory conditions. Its characterization presented here is an important step toward linking biological and chemical control within pest management regarding the lady beetle and lambda-cyhalothrin targeting different pest groups. 相似文献
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Thiago Moreno L. Souza Paola C. Resende Natalia Fintelman-Rodrigues Tatiana Schaffer Gregianini Nilo Ikuta Sandra Bianchini Fernandes Ana Luisa Furtado Cury Maria do Carmo Debur Rosa Marilda M. Siqueira 《PloS one》2013,8(11)
Although surveillance efforts that monitor the emergence of drug-resistant strains of influenza are critical, systematic analysis is overlooked in most developing countries. We report on the occurrence of strains of pandemic influenza A(H1N1)pdm09 with resistance and decreased susceptibility to oseltamivir (OST) in Brazil in 2009, 2011 and 2012. We found 7 mutant viruses, 2 with the mutation S247N and other 5 with the mutation H275Y. Most of these viruses were from samples concentrated in the southern region of Brazil. Some of these resistant viruses were detected prior to the initiation of OST treatment, suggesting that community transmission of mutant viruses may exist. Moreover, we show that one of these OST-resistant (H275Y) strains of A(H1N1)pdm09 was discovered in the tri-border region between Brazil, Argentina and Paraguay, highlighting that this strain could also be found in other Latin American countries. Our findings reinforce the importance of enhanced antiviral resistance surveillance in Brazil and in other Latin American countries to confirm or rule out the community transmission of OST-resistant strains of A(H1N1)pdm09. 相似文献
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Maria Glória Teixeira Jo?o Bosco Siqueira Jr Germano L. C. Ferreira Lucia Bricks Graham Joint 《PLoS neglected tropical diseases》2013,7(12)
A literature survey and analysis was conducted to describe the epidemiology of dengue disease in Brazil reported between 2000 and 2010. The protocol was registered on PROSPERO (CRD42011001826: http://www.crd.york.ac.uk/prospero/display_record.asp?ID=CRD42011001826). Between 31 July and 4 August 2011, the published literature was searched for epidemiological studies of dengue disease, using specific search strategies for each electronic database. A total of 714 relevant citations were identified, 51 of which fulfilled the inclusion criteria. The epidemiology of dengue disease in Brazil, in this period, was characterized by increases in the geographical spread and incidence of reported cases. The overall increase in dengue disease was accompanied by a rise in the proportion of severe cases. The epidemiological pattern of dengue disease in Brazil is complex and the changes observed during this review period are likely to have been influenced by multiple factors. Several gaps in epidemiological knowledge regarding dengue disease in Brazil were identified that provide avenues for future research, in particular, studies of regional differences, genotype evolution, and age-stratified seroprevalence.
Systematic Review Registration
PROSPERO registration number: CRD42011001826. 相似文献39.
Vinicius Bassaneze Chester Bittencourt Sacramento Rodolfo Freire Patrícia Fernandes De Alencar Neli Regina Siqueira Ortega Jose Eduardo Krieger 《PloS one》2013,8(8)
The a priori identification of induced pluripotent stem cells remains a challenge. Being able to quickly identify the most embryonic stem cell-similar induced pluripotent stem cells when validating results could help to reduce costs and save time. In this context, tools based on non-classic logic can be useful in creating aid-systems based on visual criteria. True colonies when viewed at 100x magnification have been found to have the following 3 characteristics: a high degree of border delineation, a more uniform texture, and the absence of a cracked texture. These visual criteria were used for fuzzy logic modeling. We investigated the possibility of predicting the presence of alkaline phosphatase activity, typical of true induced pluripotent stem cell colonies, after 25 individuals, with varying degrees of experience in working with murine iPS cells, categorized the images of 136 colonies based on visual criteria. Intriguingly, the performance evaluation by area under the ROC curve (16 individuals with satisfactory performance), Spearman correlation (all statistically significant), and Cohen''s Kappa agreement analysis (all statistically significant) demonstrates that the discriminatory capacity of different evaluators are similar, even those who have never cultivated cells. Thus, we report on a new system to facilitate visual identification of murine- induced pluripotent stem cell colonies that can be useful for staff training and opens the possibility of exploring visual characteristics of induced pluripotent stem cell colonies with their functional peculiarities. The fuzzy model has been integrated as a web-based tool named “2see-iPS” which is freely accessed at http://genetica.incor.usp.br/2seeips/. 相似文献