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The development of insecticide resistance in insect pests of crops is a growing threat to sustainable food production, and strategies that slow the development of resistance are therefore urgently required. The insecticide synergist piperonyl butoxide (PBO) inhibits certain insect detoxification systems and so may delay the evolution of metabolic resistance. In the current study we characterized resistance development in the silverleaf whitefly, Bemisia tabaci, after selection with either a neonicotinoid (thiacloprid) or pyrethroid ( alpha-cypermethrin) insecticide alone or in combination with PBO. Resistance development was significantly suppressed (> 60%) in the line selected with alpha-cypermethrin + PBO compared to the line selected with alpha-cypermethrin alone. RNA sequencing (RNAseq) analyses revealed an increase in frequency of a knock-down resistance mutation but no differentially expressed genes were identified that could explain the sensitivity shift. No significant difference was observed in the level of resistance between the thiacloprid and thiacloprid + PBO selected lines, and RNA sequencing (RNAseq) analyses revealed that the cytochrome P450 monooxygenase CYP6CM1, known to metabolize neonicotinoids, was significantly upregulated (>10-fold) in both lines. The findings of this study demonstrate that PBO used in combination with certain insecticides can suppress the development of resistance in a laboratory setting; however, the mechanism by which PBO supresses resistance development remains unclear. [ABSTRACT FROM AUTHOR]

Chemical insecticides have been widely used to control insect pests, leading to the selection of resistant populations. To date, several single nucleotide polymorphisms (SNPs) have already been associated with insecticide resistance, causing reduced sensitivity to many classes of products. Monitoring and detection of target-site resistance is currently one of the most important factors for insect pest management strategies. Several methods are available for this purpose: automated and high-throughput techniques (i.e. TaqMan or pyrosequencing) are very costly; cheaper alternatives (i.e. RFLP or PASA–PCRs) are time-consuming and limited by the necessity of a final visualization step. This work presents a new approach (QSGG, Qualitative Sybr Green Genotyping) which combines the specificity of PASA–PCR with the rapidity of real-time PCR analysis. The specific real-time detection of Cq values of wild-type or mutant alleles (amplified used allele-specific primers) allows the calculation of ΔCqW–M values and the consequent identification of the genotypes of unknown samples, on the basis of ranges previously defined with reference clones. The methodology is applied here to characterize mutations described in Myzus persicae and Musca domestica and we demonstrate it represents a valid, rapid and cost-effective technique that can be adopted for monitoring target-site resistance in field populations of these and other insect species. [ABSTRACT FROM PUBLISHER]

The article explores the factors that contribute to differential levels of entrepreneurial performance, which is necessary to study the specific activities of the entrepreneurs and relate them to their environment and their social background in a comparative frame. The analysis pursued in this paper is based on fieldwork undertaken during the year 1973-74 at Faridabad. The major part of the fieldwork consisted of interviews held among fifty entrepreneurs engaged in the manufacture of engineering goods and components. Faridabad has enjoyed several unique advantages which have contributed to its rapid growth as a leading industrial center of north India. Besides, proximity to Delhi also implies accessibility to central government offices and the various ministries which play a crucial role in the industrial development of the country. The Faridabad industrial complex, especially its engineering goods sector, can be portrayed as a web of economic relationships linking various industrial units. This present analysis demonstrates that one's class background sets limits not only to growth but also to the extent to which one can overcome one's constraints by expanding one's skills.

The article presents a response by the author against criticism by P.N. Rastogi, professor, Indian Institute of technology, Kanpur, India, towards his book "The Nature and Dynamics of Factional Conflict: Some Clarifications." The author responds because the criticism raises some interesting methodological issues which enables to evaluate the use of sophisticated techniques of analysis in social sciences. Rastogi's "Corpus of Propositions" expounds his theory of factional conflict best. Some of his propositions are definitional; some restates to some extent proposition; whereas some refer to the development of the conflict over time. Rastogi points out that unresolved clash of interest between prominent persons reflects the impact of major changes in social, political and economic environment of the group. This unresolved clash of interests between prominent individuals develops over time into an overt phase of conflict between factions which may later involve strategic maneuvers to defeat each other. These propositions describe the development of factionalism rather than explain it. They are mere empirical generalizations.

The present study was aimed at revealing the metabolic changes that occurred in the cellular lipid pattern of acute and chronic myeloid leukaemia cells following treatment with cannabidiol (CBD). CBD is a non-psychoactive compound present in Cannabis sativa L., which has shown an antiproliferative action in these type of cancer cells. CBD treatment reduced cell viability and initiated apoptotic and necrotic processes in both cancer cell lines in a time and dose-dependent manner, showing acute myeloid leukaemia (HL-60) cells greater sensitivity than chronic myeloid leukaemia ones (K-562), without differences in the activation of caspases 3/7. Then, control and treated cells of HL-60 and K-562 cell lines were studied through an untargeted lipidomic approach. The treatment was carried out with CBD at a concentration of 10 μM for HL-60 cells and 23 µM CBD for K-562 cells for 48 h. After the extraction of the lipid content from cell lysates, the samples were analysed by UHPLC-QTOF-MS/MS both in the positive and the negative ionization modes. The comprehensive characterization of cellular lipids unveiled several classes significantly affected by CBD treatment. Most of the differences correspond to phospholipids, including cardiolipins (CL), phosphatidylcholines (PC) and phosphosphingolipids (SM), and also triacylglycerols (TG), being many TG species increased after CBD treatment in the acute and chronic models, whereas phospholipids were found to be decreased. The results highlight some important lipid alterations related to CBD treatment, plausibly connected with different metabolic mechanisms involved in the process of cell death by apoptosis in cancer cell lines., Competing Interests: Declarations. Competing interests: The authors declare no conflict of interest., (© 2025. The Author(s).)

Background: Aphis gossypii is a worldwide agricultural pest that causes high levels of economic losses by feeding and transmitting virus diseases. It is usually controlled by chemical insecticides, but this could lead to the selection of resistant populations. Several single nucleotide polymorphisms (SNPs) have been identified associated with insecticide resistance. Monitoring activities to detect the presence of such mutations in field populations can have an important role in insect pest management but, currently, no information on Italian strains is available., Results: The presence of target site mutations conferring resistance to different insecticides was analysed in Italian field collected populations of A. gossypii with an allele specific approach (QSGG, Qualitative Sybr-Green Genotyping). Primers were designed to detect mutations in genes coding acetylcholinesterase (S431F), nicotinic acetylcholine receptor (R81T) and voltage-gated sodium channel (M918L and L1014F). S431F was widespread but with high variability across populations. R81T was detected for the first time in Italy but only in two populations. The L1014F mutation (kdr) was not found, while in the samples showing the M918L two different nucleotidic substitutions were detected. Mutant allele frequencies were, respectively, 0.70 (S431), 0.31 (M918) and 0.02 (R81). Further analysis on the voltage-gated sodium channel gene showed the presence of eight haplotypes and one non-synonymous mutation in the gene coding region., Conclusion: Multiple target-site mutations were detected within Italian populations. The combinations of genotypes observed in certain locations could affect negatively the control of this pest. Preliminary insights on the genetic structure in the Italian populations of A. gossypii were acquired. © 2024 Society of Chemical Industry., (© 2024 Society of Chemical Industry.)