Recently, the structural optimization of natural bioactive products has been one of the important ways to discover new pesticide candidates. Based on osthole as a lead compound, herein, a series of new 2-isopropanol-4-methoxy-7-alkyl/aryloxycarbonyl-()-vinyl-2,3-dihydrobenzofuran derivatives were synthesized. Steric configurations of compounds , , , , , , and were confirmed by X-ray monocrystallography.
View Article and Find Full Text PDFAlternative splicing (AS) is a universal phenomenon in eukaryotes, and it is still challenging to identify AS events. Several methods have been developed to identify AS events, such as expressed sequence tags (EST), microarrays and RNA-seq. However, EST has limitations in identifying low-abundance genes, while microarray and RNA-seq are high-throughput technologies, and PCR-based technology is needed for validation.
View Article and Find Full Text PDFTo explore natural product-based pesticide candidates, a series of indole derivatives containing the isoxazoline skeleton at the N-1 position were synthesized by 1,3-dipolar [2 + 3] cycloaddition reaction. Their structures were characterized by melting points (mp), infrared (IR) spectra, proton nuclear magnetic resonance spectra (H NMR), carbon-13 nuclear magnetic resonance spectra (C NMR), and high resolution mass spectrometry (HRMS). The single-crystal structures of five compounds were presented.
View Article and Find Full Text PDFGlobins constitute a superfamily of heme-binding proteins that is widely present in many species. There are 33 putative globins in the genome of Caenorhabditis elegans, where glb-13 is a homolog of neuroglobin (Ngb) based on sequence analysis and specific expression in neurons. Here we examined whether glb-13 as well as Ngb is also associated with resistance to reactive oxygen species (ROS) induced by paraquat.
View Article and Find Full Text PDFZhongguo Ying Yong Sheng Li Xue Za Zhi
August 2011
Objective: To develop a suitable hypoxic injury model, which is important for revealing pathological molecular mechanism of hypoxia.
Methods: We focused on C. elegans by treatment with different hypoxic times and systematically observed mortality, movement, Cellular morphology and the related-protein expression of the animals.
Five BC₁ lines and 16 house fly mass-cross homozygous lines were generated from crosses of the pyrethroid resistant ALHF (wild-type) and susceptible aabys (bearing recessive morphological markers on each of five autosomes) strains. Each of the resulting homozygous lines had different combinations of autosomes from the resistant ALHF strain. Levels of resistance to permethrin were measured for each line to determine the autosomal linkage, interaction and, possibly, regulation in pyrethroid resistance of house flies.
View Article and Find Full Text PDFPhysical and chemical hypoxia have been widely used in the study of hypoxic injury; however, both of these hypoxia models have their own limitations. Physical hypoxia is usually difficult to control and maintain. Chemical hypoxia, which is usually induced by chemical hypoxia-mimicking agents, such as CoCl(2), may result in heavy metal toxicity or impose security threats.
View Article and Find Full Text PDFThe transcriptional regulation of gene expression is a primary means by which insects adapt to a changing environment. The evolution of insecticide resistance is conferred through mechanisms, typically requiring the interaction of multiple genes. Consequently, the characterization of gene regulation and interactions in resistance is fundamental for achieving an understanding of the complex processes responsible for resistance.
View Article and Find Full Text PDFTwo mosquito strains of Culex quinquefasciatus Say, MAmCq and HAmCq, were collected from Mobile and Huntsville, AL, respectively, after the control of mosquitoes with insecticides proved difficult. A synergism study showed that resistance to chlorpyrifos in MAmCq and HAmCq was not suppressed by piperonyl butoxide (PBO) and S,S,S,-tributylphosphorotrithioate (DEF), suggesting that P450 monooxygenase- and hydrolase-mediated detoxication does not contribute to chlorpyrifos resistance in either strain. Diethyl maleate (DEM) did not cause any significant change in the level of chlorpyrifos toxicity to HAmCq.
View Article and Find Full Text PDFPest Manag Sci
November 2005
Two mosquito strains of Culex quinquefasciatus (Say), MAmCq(G0) and HAmCq(G0), were collected from Mobile and Huntsville, Alabama, respectively. MAmCq(G0) and HAmCq(G0) were further selected in the laboratory with permethrin for one and three generations, respectively. The levels of resistance to permethrin in MAmCq(G1) (after one-generation selection) and HAmCq(G3) (after three-generation selection) increased rapidly.
View Article and Find Full Text PDFJ Med Entomol
September 2004
The susceptibility of four strains of Aedes albopictus (Skuse) to permethrin, deltamethrin, resmethrin, chlorpyrifos, malathion, propoxur, fipronil, imidacloprid, spinosad, and Bacillus thuringiensis variety israelensis (Bti) was determined. The HAmAal and MAmAal strains were collected in 2002 and 2003, respectively, from Huntsville and Mobile, AL, and the VBFmAal and SFmAal strains were collected in 1998 from Vero Beach and southern Florida, respectively. The HAmAal strain showed a 22-fold elevated level of resistance to deltamethrin compared with the susceptible Ikaken laboratory strain, whereas the VBFmAal strain showed a six-fold lower sensitivity to deltamethrin compared with Ikaken.
View Article and Find Full Text PDFInsecticide resistance and cross-resistance was determined for three strains of Culex quinquefasciatus Say in the southeastern United States. HAmCq and MAmCq strains were collected in 2002 from Huntsville and Mobile, AL. The VBFmCq strain was collected in 1998 from Vero Beach, FL.
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