156 research outputs found
Sublethal effects of chlorantraniliprole and thiamethoxam seed treatments when Lysiphlebus testaceipes feed on sunflower extrafloral nectar
Citation: Moscardini, V. F., Gontijo, P. C., Michaud, J. P., & Carvalho, G. A. (2014). Sublethal effects of chlorantraniliprole and thiamethoxam seed treatments when Lysiphlebus testaceipes feed on sunflower extrafloral nectar. Retrieved from http://krex.ksu.eduThe extrafloral nectar (EFN) of sunflower, Helianthus annuus L., is an important summer resource for many insects and represents a potential route of exposure to systemic insecticides applied as seed treatments to cultivated varieties. Among the many parasitoids that utilize sunflower EFN, Lysiphlebus testaceipes (Cresson) (Hymenoptera: Braconidae) is an important generalist parasitoid of cereal aphids in North America. This study evaluated the performance of adult wasps fed EFN of sunflower plants grown from seed treated with chlorantraniliprole and thiamethoxam. Consumption of EFN from treated sunflower seedings caused no lethal effects, but reduced the numbers of greenbug nymphs, Schizaphis graminum Rondani, attacked and parasitized when wasps foraged in Petri dish arenas. Whereas control females self-superparasitized every fourth host, those exposed to chlorantraniliprole did not. Offspring developmental time and adult emergence were unaffected by either treatment, but thiamethoxam greatly reduced the proportion of female offspring
Non-target effects of chlorantraniliprole and thiamethoxam on Chrysoperla carnea when employed as sunflower seed treatments
Citation: Gontijo, P. C., Moscardini, V. F., Michaud, J. P., & Carvalho, G. A. (2014). Non-target effects of chlorantraniliprole and thiamethoxam on Chrysoperla carnea when employed as sunflower seed treatments. Retrieved from http://krex.ksu.eduThe use of systemic insecticides as seed treatments has raised concern about the possible impacts of these products on natural enemies. This study assessed the effects of sunflower seed treatments with chlorantraniliprole and thiamethoxam on Chrysoperla carnea by exposing larvae and adults to sunflower stem segments grown from treated seeds and the nectar secreted by their extrafloral nectaries. Confinement of larvae with stem segments for their entire developmental period had no effect on their survival or any life history parameter, except that the sex ratio of resulting adults was lower in the thiamethoxam treatment than in chlorantraniliprole. However, when adult pairs of C. carnea were exposed to treated stem segments during their maturation period, their subsequent survival and fecundity was significantly reduced by both materials, with thiamethoxam reducing median survival (LT[subscript 50]) and fecundity to a greater degree than chlorantraniliprole. Insufficient offspring were obtained from adults exposed to thiamethoxam to permit assessment of their fitness, but the offspring in the chlorantraniliprole-exposed adults had reduced larval survival relative to controls. The greater impact of seed treatments on adult lacewings may be partly attributable to their greater consumption of extra-floral nectar. Our results indicate that seed treatment with systemic insecticides can cause negative effects on beneficial insects, potentially disrupting their population dynamics, and should not be assumed compatible with biological control and IPM simply because this mode of application limits direct exposure
Unraveling the Paleozoic "Basement" structure and its impact on the petroleum system in the Western Gulf of Cadiz (Southwest Iberia)
A stable liquid–liquid extraction system for clavulanic acid using polymer-based aqueous two-phase systems
The partitioning of Clavulanic Acid (CA) in a novel inexpensive and stable aqueous two-phase system (ATPS) composed by poly(ethylene glycol) (PEG) and sodium polyacrylate (NaPA) has been studied.
The aqueous two-phase systems are formed by mixing both polymers with a salt (NaCl or Na2SO4) and an aqueous solution of CA. The stability of CA on the presence of both polymers was investigated and
it was observed that these polymers do not degrade the biomolecule. The effect of PEG-molecular size, polymer concentrations on the commercial CA partitioning has been studied, at 25 C. The data showed that commercial CA was preferentially partitioned for the PEG-rich phase with a partition coefficient (KCA) between 1 and 12 in the PEG/NaPA aqueous two phase systems supplemented with NaCl and
Na2SO4. The partition to the PEG phase was increased in the systems with high polymer concentrations.
Furthermore, Na2SO4 caused higher CA preference for the PEG-phase than NaCl. The systems having a composition with 10 wt.% of PEG4000, 20 wt.% of NaPA8000 and 6 wt.% of Na2SO4 were selected as the
optimal ones in terms of recovery of CA from fermented broth of Streptomyces clavuligerus. The partitioning results (KCA = 9.15 ± 1.06) are competitive with commercial extraction methods of CA
(KCA = 11.91 ± 2.08) which emphasizes that the system PEG/NaPA/Na2SO4 can be used as a new process to CA purification/concentrationFinancial support is gratefully acknowledged from FAPESP (Fundacao de Amparo a Pesquisa do Estado de Sao Paulo, Sao Paulo, Brazil) and from CNPq (National Council for Scientific and Technological Development, Brasilia, Brazil) and CAPES (Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior)
Purification of antileukemic drugs through silica-based supported ionic liquids
L-asparaginase (LA) is an enzyme used as a biopharmaceutical for the treatment of acute
lymphoblastic leukemia. LA can be produced via fermentation and its purification usually
comprises several steps including precipitation, liquid-liquid extraction and
chromatography techniques. Among these, ion exchange chromatography, which is often
preceded by precipitation with salts as a first pre-chromatographic step, is the most used.
However, theses common strategies for protein purification result in low yields and
purity, requiring long processing times, while leading to a consequent increase of the
process costs. Therefore, the demand for new cost-effective production/purification
processes play now a priority role.
This work aims the development of cost-effective technologies to purify LA from the
complex fermentation medium from Bacillus Subtillis. Silica-based supported ionic
liquids (SILs) are investigated as cost-effective purification materials for the target
enzyme. The concentration of the extract from the fermentation, material/ extract from
fermentation ratio and contact time effects in the purity and yield of LA were optimized.
With this strategy, process costs, energy consumed, and waste generated, may be
significantly decreased, which may lead to this biopharmaceutical price decrease and
wider application.publishe
Purification of antileukemic drugs through silica-based supported ionic liquids
L-asparaginase (LA) is an enzyme used as a biopharmaceutical for the treatment of acute
lymphoblastic leukemia. LA can be produced via fermentation and its purification usually
comprises ion exchange chromatography, which is often preceded by precipitation with
salts as a first pre-chromatographic step. However, this purification strategy result in
low yields and purity, requires long processing times, while leading to a consequent
increase of the process costs. Therefore, the demand for new cost-effective purification
processes play now a priority role. In this work silica-based supported ionic liquids (SILs)
are investigated as an alternative technology to purify LA from the complex
fermentation medium from Bacillus subtillis. The concentration of the extract from the
fermentation, material/ extract from fermentation ratio and contact time effects in the
purity and yield of LA were optimized. With this strategy, process costs, energy
consumed, and waste generated, may be significantly decreased, which may lead to this
biopharmaceutical price decrease and wider application.publishe
BIOTRANSFORMAÇÃO IN VITRO DE UM COMPOSTO ANTITUMORAL (LQFM 018)
Introdução e objetivos: O composto LQFM 018 foi sintetizado no Laboratório de QuímicaFarmacêutica Medicinal/FF/UFG, é um potente agente antitumoral que em ensaiostoxicológicos agudos in vitro, no modelo de vermelho neutro, não apresentou efeito tóxicosignificativo para as células basais. Estudos do metabolismo são de grande importânciapara o desenvolvimento de novos fármacos. O principal objetivo deste trabalho foi aaplicação de metodologia utilizando fungos filamentosos para mimetizar o metabolismohumano do LQFM 018 e possibilitar a preparação in vitro de metabólitos. Metodologia:LQFM 018 solubilizado em etanol/DMSO foi adicionado ao meio reacional PDSM, napresença de fungos filamentosos e foi incubados por 96 h a 27ºC sob agitação de 200rpm. Acinética reacional foi realizada por Cromatografia em Camada Delgada (CCD). Osderivados obtidos foram extraídos com acetato de etila e purificados por Cromatografia emColuna (CC) com Sílica-gel, para em seguida serem caracterizados por RessonânciaMagnética Nuclear (RMN). Resultados e discussões: Foram identificados vários fungoscapazes de catalisar a reação dando origem a cinco prováveis metabólitos Mortierellaisabelina foi a cepa mais promissora. Quantidade suficiente dos metabólitos para ensaios deatividade antitumoral foram obtidos e serão realizados posteriormente. Conclusões: Osfungos filamentosos foram capazes de biotransformar o LQFM 018, produzindo prováveismetabólitos
Down Syndrome Resulting from a Rare non-Robertsonian Translocation t(11;21)(p13;q22)
Introduction: Down syndrome (DS) is a common genetic disorder, occurring in approximately 1 in 700 births. It results from an extra copy (triplication) of the whole or part of the long arm of chromosome 21 caused by different cytogenetic alterations: free trisomy, Robertsonian translocations, mosaicism, duplication of the critical region and other structural rearrangements. Non-Robertsonian chromosome translocations are very rare events with few cases reported. Case Report: We identified the non-Robertsonian translocation t(11;21)(p13;q22) and two chromosomes 21 in a female child referred with a clinical diagnosis of trisomy 21. The infant developed the transient myeloproliferative disorder at 17 months. Cytogenetic analysis was performed in lymphocytes and bone marrow metaphases according to standard procedure - G banding and fluorescence in situ hybridization. The karyotype study of the parents revealed that her phenotypically normal mother carries the same reciprocal translocation. Conclusion: This is the second report of the translocation t(11;21)(p13;q22), the first one resulting in DS. This description expands knowledge about cytogenetic variability in the etiology of DS. Future studies are needed to investigate the long-term clinical effects of the trisomy 21 associated with t(11;21)(p13;q22)
Reference Genes for Accurate Transcript Normalization in Citrus Genotypes under Different Experimental Conditions
Real-time reverse transcription PCR (RT-qPCR) has emerged as an accurate and widely used technique for expression profiling of selected genes. However, obtaining reliable measurements depends on the selection of appropriate reference genes for gene expression normalization. The aim of this work was to assess the expression stability of 15 candidate genes to determine which set of reference genes is best suited for transcript normalization in citrus in different tissues and organs and leaves challenged with five pathogens (Alternaria alternata, Phytophthora parasitica, Xylella fastidiosa and Candidatus Liberibacter asiaticus). We tested traditional genes used for transcript normalization in citrus and orthologs of Arabidopsis thaliana genes described as superior reference genes based on transcriptome data. geNorm and NormFinder algorithms were used to find the best reference genes to normalize all samples and conditions tested. Additionally, each biotic stress was individually analyzed by geNorm. In general, FBOX (encoding a member of the F-box family) and GAPC2 (GAPDH) was the most stable candidate gene set assessed under the different conditions and subsets tested, while CYP (cyclophilin), TUB (tubulin) and CtP (cathepsin) were the least stably expressed genes found. Validation of the best suitable reference genes for normalizing the expression level of the WRKY70 transcription factor in leaves infected with Candidatus Liberibacter asiaticus showed that arbitrary use of reference genes without previous testing could lead to misinterpretation of data. Our results revealed FBOX, SAND (a SAND family protein), GAPC2 and UPL7 (ubiquitin protein ligase 7) to be superior reference genes, and we recommend their use in studies of gene expression in citrus species and relatives. This work constitutes the first systematic analysis for the selection of superior reference genes for transcript normalization in different citrus organs and under biotic stress
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