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Spirotetramat, an insecticide derived from cycloketone and extensively utilized in agricultural production, has been reported to be toxic to an array of aquatic organisms. Previous studies have indicated that spirotetramat can cause toxicity such as impaired ovarian development and apoptosis in zebrafish, but its toxicological effects on lipid metabolism and liver health in zebrafish remain unclear. In this study, we explored the effects of spirotetramat exposure on zebrafish (Danio rerio) by examining key markers of lipid metabolism, alterations in gene expression related to this process, and histological characteristics of the liver. Spirotetramat significantly reduced the condition factor, triglycerides and low-density lipoprotein cholesterol levels at 2 mg/L. The expression of genes related to fatty acid synthesis (acacb), β-oxidation (acox1, pparda) and pro-inflammatory cytokines (tnf-α, il-1β) was downregulated. However, the expression of genes related to lipid transport and uptake (cd36, ppara) and output (apob) was upregulated. The activity of alanine aminotransferase was significantly inhibited. Histopathology results showed that spirotetramat exposure led to liver cell vacuolation and necrosis. In addition, molecular docking results of spirotetramat and lipid transport related protein (ACC, ApoB) in both zebrafish and human showed the binding energy of human proteins is lower than that for zebrafish, and that the number of hydrogen bonds formed was higher. It is speculated that spirotetramat may also pose a significant potential hazard to humans, potentially affecting human lipid metabolism and health. This study expunge shed light on the ecological toxicity of spirotetramat by showing how it disrupts lipid metabolism and causes tissue damage specifically in zebrafish liver, contributing to a deeper understanding of its harmful effects in aquatic environment., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The excessive and frequent use of insecticides has led to serious problems with insecticide residues, impacting nontarget organisms such as the parasitoid Encarsia formosa. This study examined the growth, development, and enzyme activity of E. formosa exposed to spirotetramat at LC 10 , LC 30 , and LC 50 . The regression equation for the toxicity of spirotetramat toward E. formosa was Y = 5.25X-11.07. After exposure to spirotetramat, the survival rates of E. formosa sharply decreased, which occurred earlier than those in the control batch. Although the maximum daily parasitism quantity of E. formosa increased and the average parasitism number, enumerated from the 1st to the 5th day, was 53.97 after being exposed to spirotetramat at LC 10 , the life span of its F 1 generation adults was only 8.47 days, which was significantly shorter than that in the control batch. After being exposed to spirotetramat at LC 50 , the average parasitism number of E. formosa was 63.30, and the developmental time of its F 1 generation, enumerated from the 1st to the 5th day after exposure to spirotetramat, was significantly longer than that of the control batch. The activities of mixed function oxidase, acetylcholinesterase, carboxylesterase, and catalase increased significantly, and the rate of increase in enzyme activity was directly proportional to the increase in the concentration of spirotetramat. These results revealed that the parasitic ability of E. formosa decreased after exposure to spirotetramat at LC 10 , LC 30 , and LC 50 . This leads to a change in parasitoid control of pests, revealing the potential environmental threat of insecticide residues to nontarget organisms., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The aim of this study was to evaluate the sensitivity of the prawn Palaemon argentinus to the pyrethroid cypermethrin (CYP) and the tetramic acid spirotetramat (STM). These treatments were compared with prawns collected at a reference site to define their basal physiological state. Initially, physicochemical parameters and several pollutants at the selected site were analyzed. The LC 50 -96 h was determined in adult prawns. Then, prawns were exposed for 96 h to sublethal concentrations of CYP (0.0005 μg/l) and STM (0.44 mg/l) to evaluate the effects on some biochemical endpoints. A treatment combining both pesticides was also added at 5 % of these values. Controls with and without solvent (acetone) were included. The LC 50 -96 h values were 0.005 μg/l and 4.43 mg/l for CYP and STM, respectively. Moreover, some biomarkers linked to oxidative and energy metabolism were analyzed in the hepatopancreas and muscle of both essayed prawns and those at the basal state. The STM caused a significant decrease in total protein content (32 %) in contrast to the increase of protein carbonyl content (71 %) (p < 0.05). Also, glutathione S-transferase (52 %) and catalase (61 %) activities in the hepatopancreas of exposed prawns were higher compared to both the control and state basal groups (p < 0.05). In muscle, only a significant decrease in the lactate content (69 %) was caused by STM (p < 0.05). In addition, CYP caused a significant increase in the lactate dehydrogenase activity (110 %) in muscle and triacylglycerol content (73 %) in the hepatopancreas (p < 0.05). The integrated biomarker index (IBRv2) analysis showed that STM caused greater damage than CYP. Besides, the combined treatment showed an antagonistic interaction between both insecticides. The differential response of biomarkers to both CYP and STM exposure with respect to their basal levels shows a high sensitivity of P. argentinus demonstrating its potential role as a bioindicator organism., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Spirotetramat is a novel insecticide and acaricide that can effectively control many species of piercing-sucking pests by inhibiting lipid synthesis. The silkworm is an economically important insect and a model organism for genetics and biochemical research. However, the toxic effect on their development and reproduction remain unclear. In this study, we demonstrated the negative effects of spirotetramat on the development, vitality, silk protein synthesis, and fecundity of silkworm. We also compared expression changes of silkworm genes using digital gene expression (DGE). A total of 1567 differentially expressed genes (DEGs) were detected, of which 874 genes were downregulated and 693 genes were upregulated. Gene Ontology (GO) enrichment analysis showed that the DEGs were enriched in the oxidation-reduction process, oxidoreductase activity, and fatty-acyl-CoA reductase activity. Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis showed that the DEGs were mainly enriched in fatty acid metabolism and lysosome pathways. We detected the relative expression of silkworm genes related to fatty acid synthesis and decomposition pathways and the degradation pathway of juvenile hormone by quantitative real-time PCR. The expression levels of Acetyl CoA carboxylase (ACC), fatty acyl-CoA reductase (FACR), Enoyl-CoA hydratase (ECH), very-long-chain (3R)-3-hydroxyacyl-CoA dehydratase (LCHAD), juvenile hormone epoxide hydrolase (JHEH), and phytanoyl-CoA dioxygenase (PCD) genes were downregulated. These data demonstrate the effects of spirotetramat on silkworm and its effects on genes involved in fatty acid metabolism., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022. Published by Elsevier Inc.)

Background: The use of chemical insecticides to control Bemisia tabaci Gennadius (Hemiptera: Aleyrodidae) is widespread, although it might exert a sublethal effect on its dominant parasitoid, Encarsia formosa Gahan (Hymenoptera: Aphelinidae). To investigate the sublethal effect of spirotetramat on E. formosa, we observed the ability of E. formosa to locate and handle the host, oviposit and preen after exposure to sublethal concentrations of spirotetramat., Results: After exposure to spirotetramat at LC 50 , the response time of E. formosa to the volatile reached 223.40 s and was significantly prolonged. Only 56.44% of the wasps were attracted by the volatile and the insect crawled the slowest among all of the treatments. The averages of oviposition posture adopted and host handled by each E. formosa in 1 h decreased significantly to 1.79 and 1.27, respectively. At the sublethal concentration of LC 10 , 94.59% of the wasps were attracted by the volatile and the insect crawled the fastest. The average of host handled by each E. formosa was 3.92, and the frequency of drumming while walking and drumming the host was 12.34 times per second and 12.30 times per second, respectively, demonstrating a significant acceleration in these abilities., Conclusion: These findings demonstrate that spirotetramat induced hormesis in E. formosa on exposure to its LC 10 concentration and accelerated its host locating, host handling and frequency of antennae drumming. These findings could assist in balancing the chemical and biological control of B. tabaci and enhancing the efficacy of E. formosa as a biocontrol agent. © 2021 Society of Chemical Industry., (© 2021 Society of Chemical Industry.)

Frankliniella occidentalis (Pergande) has become an important vegetable pest worldwide because of its economic damage to crop production. However, it is difficult to control due to its unique living habits. In this study, the eggs of F. occidentalis were used as the target to explore the ovicidal activity of spirotetramat on the thrips and its effect on hatching, development and formation. After the treatment of spirotetramat, the LC 50 value descreased with increased egg age using egg dipping method, and showed the same trend as the leaf dipping method verified on living plants. Through ultra-depth-of-field microscopy, scanning electron microscopy and transmission electron microscopy, the egg shell and internal structures of F. occidentalis eggs were studied. Spirotetramat can destroy the egg shells of F. occidentalis, resulting in shrinkage of the egg surface, sunken pores, egg deformities, egg shell rupture and other phenomena. This allows spirotetramat to enter the egg and destroy the egg structure, making the egg internal structure flocculent, fuzzy and unevenly distributed, which affects embryonic development and causes the nymphs to die before hatching. Therefore, the prevention and control of F. occidentalis using spirotetramat before damage is caused to crops should have a better effect., (© 2021. The Author(s).)

Background: The Asian citrus psyllid (ACP), Diaphorina citri Kuwayama, is one of the most devastating pests in citrus orchards, and has caused huge economic losses worldwide. Chemical control is the most effective way for psyllid control. Herein, the toxicity of nine insecticides to ACP adults and the joint action of thiamethoxam + spirotetramat were determined by a topical application method in the laboratory; field plot experiments were conducted to evaluate the control efficacy of one self-made thiamethoxam + spirotetramat 40% suspension concentrate (SC) comparing with thiamethoxam 21% SC, spirotetramat 22.4% SC, tolfenpyrad 15% SC and bifenthrin 100 g/L emulsifiable concentrate against ACP using foliar sprays in 2018-2019., Results: The highest toxicity to ACP adults was achieved by beta-cyfulthrin, bifenthrin, thiamethoxam and acetamiprid, with median lethal doses of 0.247 to 1.382 ng/adult at 24 h after treatment. High toxicity was observed by chlorpyrifos, spirotetramat and tolfenpyrad, but moderate toxicity by pyriproxyfen and buprofezin. For mixutres of thiamethoxam and spirotetramat, a 25:15 mass ratio showed the highest synergistic effect, with a co-toxicity coefficient (CTC) of 246.52; while a 10:30 mass ratio exhibited an additive effect, with a CTC of 109.84. Thiamethoxam + spirotetramat 40% SC at 60-80 mg/kg can effectively control ACP with a control efficacy of 72.92 to 99.29% during 3-30 days. Moreover, foliar sprays of all tested insecticides at the tested rates had no phytotoxic effects on citrus trees., Conclusion: A one-time foliar spray of thiamethoxam + spirotetramat 40% SC at 80 mg/kg could be recommended to control ACP during its infestation period in citrus groves., (© 2020 Society of Chemical Industry.)

The honey bee, Apis mellifera L., is the world's most important managed pollinator of agricultural crops, however, Varroa mite, Varroa destructor Anderson and Trueman, infestation has threatened honey bee survivorship. Low efficacy and development of Varroa mite resistance to currently used Varroacides has increased the demand for innovative, effective treatment tool options that exhibit high efficacy, while minimizing adverse effects on honey bee fitness. In this investigation, the toxicity of 16 active ingredients and 9 formulated products of registered miticides for use on crops from 12 chemical families were evaluated in comparison to amitraz on Varroa mites and honey bees using contact surface and topical exposures. It was found that fenpyroximate (93% mortality), spirotetramat (84% mortality) and spirodiclofen (70% mortality) had greater toxicity to Varroa mites, but high dose rates caused high bee mortality (> 60%). With this in mind, further research is needed to investigate other options to minimize the adverse effect of these compounds on bees. The results also found high toxicity of fenazaquin and etoxazole against Varroa mites causing 92% and 69% mortality, respectively; and were found to be safe on honey bees. Collectively, it is recommended that fenazaquin and etoxazole are candidates for a potential Varroacide and recommended for further testing against Varroa mites at the colony level.

Spirotetramat (SPT) is a new tetronic acid derivative insecticide used to control scales and aphids; the potential for endocrine disruptor effects in fish could not be finalized with the available data. In this study, zebrafish were selected to assess the endocrine-disrupting effects. Significant decrease of plasma estradiol (E2), testosterone (T) and 11-ketotestosterone (11-KT) were observed in both male and female following the spirotetramat exposure; the vitellogenin (VTG) level in females significantly decreased. The expression of the hypothalamic-pituitary-gonad (HPG) axis genes fshr, lhr and esr1 showed significant increase in the gonads, which expression in males is higher than in females. In addition, the activities of capspase-3 and caspase-9 significantly decreased in both males and females liver, while the capspase-3 and caspase-9 were increased in male testis, the mRNA expression levels of genes expression related to the apoptosis pathway were also significantly altered after the spirotetramat exposure. Additionally, we found the parental zebrafish exposed to spirotetramat induced the development delay of its offspring. Above all, the adverse effects induced by spirotetramat suggesting that spirotetramat is a potential exogenous hazardous agent., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Spirotetramat is a toxic commercially known as Movento used to control pistachio psylla pests. In the present study, the effects of Movento on passive avoidance learning of rats and their ability to explore the novel object in the novel object recognition test were investigated. The changes in the concentration of hippocampal brain-derived neurotrophic factor (BDNF) proteins were evaluated, too. Male Wistar rats were gavaged at different dosages of the Movento (50, 100, 250, 500, 1000, 1250, and 1500 mg/kg) or saline for 7 days (administered every 2 days). We showed that Movento caused 50 and 100% mortality at the dose of 1250 and 1500 mg/kg, respectively. At the dose of 1000 mg/kg, Movento significantly decreased locomotor activity (P < 0.05). These rats also displayed a significant decrease in the number of training trials in the shuttle box and the ability to recognize a novel object compared with the control group (P < 0.01). The BDNF protein level of hippocampus also showed a significant decrease in the Movento (1000 mg/kg) compared with the control group (P < 0.01) while the number of pancellular necrosis pyramidal CA1 cells increased significantly in the Movento group (P < 0.001). We concluded that exposure to Movento can decline sensory, motor, and learning in rats.

Spirocyclic tetramic acids are widely used in controlling phytophagous mite species throughout the world. the data set is incomplete and provides insufficient evidence for drawing the same conclusion for fish. To fill the gap whether these acaricides alter lipid metabolism on vertebrates, zebrafish embryos exposed to a series concentration of pesticides, the developmental effects, enzyme activities and levels of gene expression were assessed, battery of biomarker utilized by the integrated biomarker response (IBRv2) model. The 96 h-LC 50 of spirodiclofen, spiromesifen and spirotetramat were 0.14, 0.12 and 5.94 mg/L, respectively. Yolk sac deformity, pericardial edema, spinal curvature and tail malformation were observed. Three spirocyclic acids were unfavouring the lipid accumulation of by inhibited the acetyl-CoA carboxylase (ACC), fatty acid synthesis (FAS), fatty acid binding proteins (FABP2) and lipoprotein lipase (LPL) activity. The total cholesterol (TCHO) level significantly decreased in the 0.072 mg/L spirodiclofen group and 0.015 and 0.030 mg/L in the spiromesifen groups. No expected change in spirotetramat group on the TCHO and triglycerides (TGs) levels for any of the treatments. The mRNA levels of the genes related to lipid metabolism also significantly altered. In both spirodiclofen and spiromesifen, ACC achieved the highest scores among a battery of biomarkers using integrated biomarker response (IBRv2). The results suggest that spiromesifen was the most toxic for embryos development and spirodiclofen was the most toxic for lipid metabolism in embryos. The 0.07 mg/L of spirodiclofen, 0.05 mg/L of spiromesifen and 2.00 mg/L would cause malformation on zebrafish embryos. This study will provide new insight that fatty acid metabolism may be a suitable biomarker for the spirocyclic tetramic acids in fish species., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

As a new tetronic acid derivative insecticide, spirotetramat has been reported to be toxic to an array of aquatic organisms. However, the toxic effects of spirotetramat on zebrafish especially at ovary are still obscure. Hereby, the acute toxicity of spirotetramat towards zebrafish（Danio rerio），as well as the changes on biochemical and histological traits of ovary were investigated. The acute toxicity test results showed that the median lethal concentration (LC 50 ) value of spirotetramat were 9.61 mg/L and 7.21 mg/L at 72 h and 96 h, respectively, suggesting spirotetramat has moderate toxicity to zebrafish. In the following sub-lethal toxicity test, the gene expression of superoxide dismutase (SOD), catalase (CAT), and gonadotropic hormone receptor (FSHR and LHR) together with the content of malondialdehyde (MDA) in ovary were measured at 14, 21, and 28 days after exposure to 36, 360 and 720 μg/L. Under high concentration treatment (360 and 720 μg/L), MDA content, the relative transcription CAT and SOD gene level increased significantly in ovary (p < 0.05). That indicated sub-lethal doses spirotetramat caused oxidative stress and lipid peroxidation in zebrafish ovary during the entire experimental period. Under the exposure to spirotetramat at 720 μg/L after 14 days, the relative transcript FSHR gene level was down regulated, and the relative transcript LHR gene level was up regulated. Moreover, spirotetramat affected the oocyte development especially on the diameter size and maturation during the ovary tissue biopsies at 28 days. Taken together, these findings revealed the adverse effects of spirotetramat on fish from the biochemical and histological aspects., (Copyright © 2018 Elsevier Inc. All rights reserved.)

The cytochrome P450 monooxygenases play a key role in detoxification mechanism for spirotetramat resistance in Aphis gossypii Glover. However, only one P450 genes (CYP6DA2), among thirty-five P450 genes identified from Aphis gossypii transcriptome database, has been reported to play important role in spirotetramat resistance in previous resistance level until now. In this study, after the confirmation of the rise of resistance level and important roles of P450s in spirotetramat resistance by the synergism analysis, the gene expression changes were determined for P450 genes in spirotetramat susceptible and resistant strains. Compared with the susceptible strain, CYP6CY4, CYP6CY14, CYP6CY18 and CYP6DC1 in CYP3 Clade were up-regulated in resistant nymphs, with the CYP6CY14, CYP6CY4, CYP6DC1, and CYP6CY18 increased to 2.54-, 1.51-, 1.31- and 1.29-fold, respectively. Eight genes in CYP3 Clade, three genes in CYP4 Clade and one gene in Mito Clade were down-regulated. In resistant adult aphids, CYP380C6 in CYP4 Clade, CYP353B1 in CYP2 Clade, and CYP307A1 in Mito Clade were up-regulated under spirotetramat stress, with the CYP380C6, CYP353B1 and CYP307A1 increased to 2.89-, 1.91-, and 1.38-fold, respectively. In contrast, the other P450 genes were almost down-regulated, especially these P450 genes in CYP3 Clade, CYP4 Clade and Mito Clade. RNA interference of CYP380C6 significantly increased the sensitivity of the resistant adults and nymphs to spirotetramat, while suppression of CYP6CY14 could not increase the toxicity of spirotetramat. These results indicate the possible involvement of the CYP380C6 genes in spirotetramat resistance at present very high resistance levels. Screening the expression changes of P450 genes under different spirotetramat resistance levels in the genome-scale will provide an overall view on the possible metabolic factors in the resistance development. The results may facilitate further work to validate the roles of P450 in spirotetramat resistance with heterologous expression., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Individual effects of nitrogen-based energetic materials (EMs) 2,4-dinitrotoluene (2,4-DNT), 2-amino-4,6-dinitrotoluene (2-ADNT), 4-amino-2,6-dinitrotoluene (4-ADNT), nitroglycerin (NG), and 2,4,6,8,10,12-hexanitrohexaazaisowurtzitane (CL-20) on litter decomposition, an essential biologically-mediated soil process, were assessed using Orchard grass (Dactylis glomerata) straw in Sassafras sandy loam (SSL) soil, which has physicochemical characteristics that support "very high" qualitative relative bioavailability for organic chemicals. Batches of SSL soil were separately amended with individual EMs or acetone carrier control. To quantify the decomposition rates, one straw cluster was harvested from a set of randomly selected replicate containers from within each treatment, after 1, 2, 3, 4, 6, and 8 months of exposure. Results showed that soil amended with 2,4-DNT or NG inhibited litter decomposition rates based on the median effective concentration (EC50) values of 1122 mg/kg and 860 mg/kg, respectively. Exposure to 2-ADNT, 4-ADNT or CL-20 amended soil did not significantly affect litter decomposition in SSL soil at ≥ 10,000 mg/kg. These ecotoxicological data will be helpful in identifying concentrations of EMs in soil that present an acceptable ecological risk for biologically-mediated soil processes., (Published by Elsevier Inc.)

With the purpose of guaranteeing the safe use of spirotetramat and preventing its potential health threats to consumers, a QuEChERS extraction method coupled with LC triple-quadrupole tandem MS was applied in this study to determine residual spirotetramat metabolites in different tissues of amaranth (Amaranthus tricolor) and in soil. The results indicate that the spirotetramat degraded into different types of metabolites that were located in different tissues of amaranth and in soil. B-keto, B-glu, and B-enol were the three most representative degradation products in the leaf of amaranth, and B-glu and B-enol were the two major degradation products found in the stem of amaranth; however, only B-enol was detected in the root of amaranth. B-keto and B-mono were the two products detected in the soil in which the amaranth grew. The cytotoxicity results demonstrate that spirotetramat and its metabolite B-enol inhibited cellular growth, and the toxicity of spirotetramat and its metabolite B-enol exceeded than that of the metabolites B-keto, B-mono, and B-glu. This investigation is of great significance to the safe use of spirotetramat in agriculture.

Conventional insecticide assays, which measure the effects of insecticide exposure on short-term mortality, overlook important traits, including persistence of toxicity or sub-lethal effects. Therefore, such approaches are especially inadequate for prediction of the overall impact of insecticides on beneficial arthropods. In this study, the side effects of four modern insecticides (chlorantraniliprole, emamectin benzoate, spinosad, and spirotetramat) on Adalia bipunctata (L.) (Coleoptera: Coccinellidae) were evaluated under laboratory conditions by exposition on treated potted plants. In addition to investigation of acute toxicity and persistence of harmful activity in both larvae and adults of A. bipunctata, demographic parameters were evaluated, to provide a comprehensive picture of the nontarget effects of these products. Field doses of the four insecticides caused detrimental effects to A. bipunctata; but in different ways. Overall, spinosad showed the best toxicological profile among the products tested. Emamectin benzoate could be considered a low-risk insecticide, but had high persistence. Chlorantraniliprole exhibited lethal effects on early instar larvae and adults, along with a long-lasting activity, instead spirotetramat showed a low impact on larval and adult mortality and can be considered a short-lived insecticide. However, demographic analysis demonstrated that chlorantraniliprole and spirotetramat caused sub-lethal effects. Our findings highlight that sole assessment of mortality can lead to underestimation of the full impact of pesticides on nontarget insects. Demographic analysis was demonstrated to be a sensitive method for detection of the sub-lethal effects of insecticides on A. bipunctata, and this approach should be considered for evaluation of insecticide selectivity., (© The Author(s) 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

The negative impact of conventional pesticides on the environment is already extensively discussed worldwide. Although the use of chemical agents for controlling agricultural pests remains as first-line strategy for pest control, novel biorational active insecticides, such as spirotetramat, have appeared in the pesticide market during recent years in Argentina. The aim of this study was to assess the toxicity of spirotetramat on two developmental stages of a Neotropical strain of Eretmocerus mundus, with the conventional insecticide cypermethrin as a positive control, and to determine spirotetramat's side effects on parasitoid demographic parameters. Lethal effects of both insecticides on pupae and adults were evaluated by adult emergency and survival, respectively; whereas sublethal effects on both development stages were assessed by adult longevity, reproduction capacity, sex ratio, and longevity of the first progeny. Spirotetramat proved less harmful than cypermethrin at both developmental stages studied, corroborating once more the high toxicity of this pyrethroid to natural enemies. Although spirotetramat did not affect the emergence and reproductive capacity of adults surviving pupal exposure, the longevity of the first progeny was reduced as was adult survival and longevity after exposure to residues. Spirotetramat also reduced all demographic parameters in the population evaluation. This work is the first report of spirotetramat toxicity at the population level and demonstrates the need to assess the total effect of pesticides on natural enemies.

Antidesmone, isolated from Waltheria brachypetala Turcz., owns special structural features as two α,β-unsaturated carbonyl groups and a side alkyl chain that can compete with the quinones involved in the pool of plastoquinones at photosystem II (PSII). In this work, we showed that the alkaloid is an inhibitor of Hill reaction and its target was located at the acceptor side of PSII. Studies of chlorophyll (Chl) a fluorescence showed a J-band that indicates direct action of antidesmone in accumulation of Q A - (reduced plastoquinone A) due to the electron transport blocked at the Q B (plastoquinone B) level similar to DCMU. In vivo assays indicated that antidesmone is a selective post-emergent herbicide probe at 300μM by reducing the biomass production of Physalis ixacarpa plants. Furthermore, antidesmone also behaves as pre-emergent herbicide due to inhibit Physalis ixacarpa plant growth about 60%. Antidesmone, a natural product containing a 4(1H)-pyridones scaffold, will serve as a valuable tool in further development of a new class of herbicides., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Spirotetramat is a novel tetramic acid-based insecticide, belonging to keto-enol pesticide family, with a novel mode of action; it interferes with lipid biosynthesis. Its insecticide activity against various agricultural pest insects have been demonstrated (e.g. on Myzus persicae, Bemisia tabaci and Tetranychus urticae). However, information available is currently limited on the efficacy of spirotetramat on the cotton aphid, Aphis gossypii, a key cotton pest worldwide. We assessed the spirotetramat toxicity on A. gossypii and evaluated its effects on aphid fecundity when exposed to a sublethal concentration (LC10) and to increasing lethal concentrations (LC25, LC50, and LC75). A key mechanism involved in insecticide resistance in aphids relates to esterase activity. We estimated the CarE activity and a CarE gene expression in aphids in response to spirotetramat exposure, then we tested tolerance of offspring to spirotetramat when the parents were exposed to the highest concentration tested in our study (LC75). Results showed that spirotetramat showed increasing toxicity to A. gossypii with exposure duration to treated leaves; LC50 ranged from 23,675.68 to 12.27 mg/L for 1 to 5-days exposure. In addition, spirotetramat reduced aphid daily fecundity, in all concentration treatments, especially with up to 90 % reduction in case of exposure to LC75. Total CarE activity increased dramatically and CarE mRNA expression was also up regulated in aphids after exposure to LC75 spirotetramat. Finally, the tolerance to spirotetramat in offspring (when parents were exposed to the LC75) showed a 2.5-fold increase when compared to control aphids. Consequently, spiroteramat showed potential for pest management of cotton aphids owing to both lethal and sublethal activities, notably strong impact on aphid fecundity. However, we also demonstrated that increased tolerance of A. gossypii to spirotetramat may happen through increased CarE- activity and subsequent metabolic degradation of the insecticide in aphids' body.

The peptide bond-forming reagents 1-hydroxy-7-azabenzotriazole (HOAt, CAS 39968-33-7) and O-(7-Azabenzotriazol-1-yl)-N,N,N',N'-tetramethyluronium hexafluorophosphate (HATU, CAS 148893-10-1) either have structural alerts, unclassified features or are considered out of domain when evaluated for potential mutagenicity with in silico programs DEREK and CaseUltra. Since they are commonly used reagents in pharmaceutical drug syntheses, they may become drug substance or drug product impurities and would need to be either controlled to appropriately safe levels or tested for mutagenicity. Both reagents were tested in the bacterial reverse mutation (Ames) test at Covance, under GLP conditions, following the OECD test guideline and ICH S2(R1) recommendations and found to be negative. Our data show that HOAt and HATU-common pharmaceutical synthesis reagents-are not mutagenic, and can be treated as ordinary drug impurities., (© 2016 Wiley Periodicals, Inc.)

A laboratory-selected spirotetramat-resistant strain (SR) of cotton aphid developed 579-fold and 15-fold resistance to spirotetramat in adult aphids and 3rd instar nymphs, respectively, compared with a susceptible strain (SS) [26]. The SR strain developed high-level cross-resistance to alpha-cypermethrin and bifenthrin and very low or no cross-resistance to the other tested insecticides. Synergist piperonyl butoxide (PBO) dramatically increased the toxicity of spirotetramat and alpha-cypermethrin in the resistant strain. RT-qPCR results demonstrated that the transcriptional levels of CYP6A2 increased significantly in the SR strain compared with the SS strain, which was consistent with the transcriptome results [30]. The depletion of CYP6A2 transcripts by RNAi also significantly increased the sensitivity of the resistant aphid to spirotetramat and alpha-cypermethrin. These results indicate the possible involvement of CYP6A2 in spirotetramat resistance and alpha-cypermethrin cross-resistance in the cotton aphid. These together with other cross-resistance results have implications for the successful implementation of resistance management strategies for Aphis gossypii., (Copyright © 2015 Elsevier B.V. All rights reserved.)

The aim of this study was to evaluate the potential toxicity of spirotetramat to the earthworm Eisenia fetida in a natural soil environment. Many biochemical markers, viz., superoxide dismutase (SOD), catalase (CAT), peroxidase (POD), glutathione S-transferase (GST), cellulase, and malondialdehyde (MDA) contents were measured after exposure to 0.25, 1.25, and 2.5mgkg(-1) for 2, 7, 14, 21, and 28days. In addition, the comet assay was performed on earthworm coelomocytes to assess the level of genetic damage. The results demonstrate that the SOD activity and MDA content were significantly stimulated by the highest dose (2.5mgkg(-1)) of spirotetramat for the entire period of exposure. The activities of CAT and POD increased significantly by 2d and 21d, respectively, but the activities of both were significantly inhibited after prolonged exposure (28d). After an initial increase on the 2nd day, the cellulase activity in the high-dose treatment group was significantly inhibited for the entire remaining exposure period. The comet assay results demonstrate that spirotetramat (⩽2.5mgkg(-1)) can induce low and intermediate degrees of DNA damage in earthworm coelomocytes. The results indicate that spirotetramat may pose potential biochemical and genetic toxicity to earthworms (E. fetida), and this information is helpful for understanding the ecological toxicity of spirotetramat on soil invertebrate organisms., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

A resistant strain of the cotton aphid (SR) developed 441.26-fold and 11.97-fold resistance to spirotetramat for adult aphids and nymphs, respectively, compared with the susceptible (SS) strain. Solexa sequencing technology was employed to identify differentially expressed genes (DEGs) in the spirotetramat-resistant cotton aphid. Respective totals of 22,430,522 and 21,317,732 clean reads were obtained from SR and SS cDNA libraries and assembled into 35,222 non-redundant (Nr) consensus sequences. A total of 14,913, 9,220, 7,922, 4,314 and 4,686 sequences were annotated using Nr, Swiss-Prot, Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) and Clusters of Orthologous Groups (COG), respectively. Compared with the SS strain, the SR strain had 1287 significantly changed unigenes, of which 130 genes were up-regulated and 1157 genes were down-regulated (P ≤ 0.001). Among these genes, 440 unigenes were annotated, consisting of 114 up-regulated and 326 down-regulated genes. The expression levels of heat shock protein 70 (Hsp70) and UDP-glucuronosyltransferase were significantly up-regulated in the SR strain compared to the SS strain. The genes encoding cuticle proteins, salivary glue protein, fibroin heavy chain, energy ATP synthase, and cytochrome c oxidase were dramatically decreased. Among the DEGs, cytochrome P450 6A2 (c20965.graph&#95;c0) was the only P450 gene up-regulated in the SR strain. The expression levels of 10 DEGs were confirmed by real-time qPCR, and the trends in gene expression observed by qPCR matched those of the Solexa expression profiles. The acetyl-CoA carboxylase (ACC) genes in the SR and SS libraries both contain four single nucleotide polymorphisms (SNPs), with three common SNPs: 1227 (C/T), 1811 (A/T: F/Y) and 3759 (C/T); however, 7540 (A/T) and 108 (G/A) occurred solely in the SS and SR strains, respectively., (Copyright © 2015 Elsevier Inc. All rights reserved.)

The guardian of the genome, p53, is the most mutated protein found in all cancer cells. Restoration of wild-type activity to mutant p53 offers promise to eradicate cancer cells using novel pharmacological agents. Several molecules have already been found to activate mutant p53. While the exact mechanism of action of these compounds has not been fully understood, a transiently open pocket has been identified in some mutants. In our study, we docked twelve known activators to p53 into the open pocket to further understand their mechanism of action and rank the best binders. In addition, we predicted the absorption, distribution, metabolism, excretion and toxicity properties of these compounds to assess their pharmaceutical usefulness. Our studies showed that alkylating ligands do not all bind at the same position, probably due to their varying sizes. In addition, we found that non-alkylating ligands are capable of binding at the same pocket and directly interacting with Cys124. The comparison of the different ligands demonstrates that stictic acid has a great potential as a p53 activator in terms of less adverse effects although it has poorer pharmacokinetic properties., (© 2014 John Wiley & Sons A/S.)

In the West African savanna zone, traditional subsistence farming increasingly shifts to cash crop farming and in particular to cotton cultivation, which is accompanied by application of pesticides. Increasing use of pesticides by smallholder farmers is suspected to have negative effects on non-target organisms. In this study, possible pesticide impact on the development of tadpoles was investigated. Two insecticide formulations used in cotton cultivation in Benin were compared: Cotofan® (active ingredient (a.i.): α- and β-endosulfan) and Tihan® (a.i.: spirotetramat and flubendiamide). Tadpoles of the widespread species Amietophrynus maculatus were kept in small water basins with increasing insecticide concentrations (1, 10 and 100 μg a.i./L) over a period of 28 days. Tadpoles showed reduced survival at the highest endosulfan concentrations (100 μg/L). Survival of tadpoles undergoing metamorphosis was not influenced by Tihan®. Endosulfan in concentrations of 10 and 100 μg/L negatively impacted the movement of the tadpoles which was not the case for the mixture of spirotetramat and flubendiamide. Time to metamorphosis was not significantly different in the various treatments. Tail length of tadpoles was significantly shorter in Cotofan® treatments compared to controls. Pesticide residues in the tadpoles were relatively low after keeping them in concentrations of 1 and 10 μg a.i./L (25 and 26 μg/kg wet weight (w/w) for the sum of α-endosulfan, β-endosulfan and endosulfan sulphate and below the detection limits for flubendiamide and spirotetramat). For the 100 μg a.i./L treatments, 1,600 μg/kg w/w was found of α-endosulfan, β-endosulfan and endosulfan sulphate together in the survived tadpoles and 21 μg/kg w/w of flubendiamide.

The aim of this work was to evaluate the potential effects of antioxidant and lipid peroxidation parameters as indicators of exposure to spirotetramat and effects of acute toxicity in the Chinese toad Bufo bufo gargarizans. The results of an acute toxicity test showed that the 72 and 96 h median lethal concentrations (LC(50)) of spirotetramat for tadpoles were 6.98 and 6.45 mg/L, respectively. It indicated that the spirotetramat was moderate toxicity to Chinese toad tadpoles. In a sub-lethal toxicity test, the superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and malondialdehyde (MDA) contents were determined after exposure to 0.03, 0.06, 0.13, 0.65, and 3.23 mg/L for 4, 15, and 30 days. SOD activity significantly in all experimental groups except the highest concentration group increased on day 4 but decreased on days 15 compared with that of the acetone control (P < 0.05). The most sensitive parameters was GSH-Px activity, which significantly increased on day 4, but was inhibited and decreased after prolonged exposure for 15 and 30 days except the lowest concentration treatment group (P < 0.05). The MDA content significantly decreased on day 30 (P < 0.05). During the entire experimental period, sub-lethal doses spirotetramat caused oxidative stress and lipid peroxidation in B. gargarizans tadpoles. These results indicate that sub-lethal even non-lethal spirotetramat are potentially toxic to amphibians. The information presented in this study will be helpful for understanding oxidative stress induced by spirotetramat in aquatic organisms., (Copyright © 2014 Elsevier B.V. All rights reserved.)

In the development of new drugs, it is very important to know the effects these may bring to those who consume them. Drugs which act upon certain diseases must not cause toxic side effects on healthy organs. These toxic side effects can be quite varied, i.e. mutagenicity, clastogenicity, teratogenicity, etc., but undoubtedly the mutagenicity officiate in the selection process, during preclinical testing, to advance in clinical trials. Mutagenic compounds are removed and cannot continue its development. There are preclinical studies of mutagenicity and genotoxicity, ranging from in vitro to in vivo studies. Particularly, Ames test is recommended by ICH as the first input in these studies. Herein, we investigated the mutagenicity of an in-house chemical library of eighty five N-oxide containing heterocycles using Ames test in Salmonella thyphimurium TA 98 with and without S9 activation and the use of neural networks in order to predict this nondesired activity. N-oxide containing heterocycles are especially relevant regarding its pharmacological activities as antitrypanosoma, anti-leishmania, anti-tuberculosis, anti-cancer, chemopreventive, anti-inflammatory, anti-atherogenic, and analgesic agents. In some cases, a relationship was found between the presence of N-oxide and mutagenicity. Specifically, benzofuroxan system seems to be responsible for the mutagenicity of certain agents against Chagas disease and certain anti-inflammatory agents. However other N-oxides, such as furoxans with anti-inflammatory and anti-atherosclerosis activities, seem to lack mutagenicity. In other cases, such as quinoxaline dioxides with anti-parasitic activity, mutagenicity shows to be substituent dependent. Applying CODES neural network two models were defined, one without metabolism and other with metabolism. These models predict the mutagenicity with and without metabolism in an excellent manner.

We have synthesized and characterized a series of compounds containing the 3-azatetracyclo[5.2.1.1(5,8).0(1,5)]undecane scaffold designed as analogues of amantadine, an inhibitor of the M2 proton channel of influenza A virus. Inhibition of the wild-type (WT) M2 channel and the amantadine-resistant A/M2-S31N and A/M2-V27A mutant ion channels were measured in Xenopus oocytes using two-electrode voltage clamp (TEV) assays. Most of the novel compounds inhibited the WT ion channel in the low micromolar range. Of note, several compounds inhibited the A/M2 V27A mutant ion channel, one of them with submicromolar IC50. None of the compounds was found to inhibit the S31N mutant ion channel. The antiviral activity of three novel dual WT and A/M2-V27A channels inhibitors was confirmed by influenza virus yield assays.

Introduction: Preclinical assessment of the heart rate corrected QT interval (QTc) is an important component of the cardiovascular safety evaluation in drug discovery. Here we aimed to quantify the translational relationship between QTc prolongation and shortening in the conscious telemetered dog and humans by a retrospective pharmacokinetic-pharmacodynamic (PKPD) analysis., Methods: QTc effects of 2 proprietary compounds and 2 reference drugs (moxifloxacin and dofetilide) were quantified in conscious dogs and healthy volunteers via a linear and Emax pharmacokinetic-pharmacodynamic models. The translational relationship was quantified by correlating the QTc response from dog and human at matching free drug concentrations., Results: A consistent translational relationship was found at low delta-QTc intervals indicating that a QTc change of 2.5-8 ms in dog would correspond to a 10 ms change in human., Discussion: The translational relationship developed here can be used to predict the QTc liability in human using preclinical dog data. It could therefore help protect the health of human volunteers, for example by appropriate clinical study design and dose selection, as well as improve future decision-making and help reduce compound attrition due to changes in QT interval., (Copyright © 2013 Elsevier Inc. All rights reserved.)

Background: In previous studies, scientists found that, when spirotetramat was introduced into plants or animals, it was mainly metabolised at positions C-4 and C-8. That is to say, these two functional positions potentially played an important role in spirotetramat's bioactivities. In order to develop novel insecticides or miticides, the present authors designed and synthesised 35 spirotetramat analogues based on metabolite structures., Results: All of the analogues have been identified on the basis of (1)H NMR, ESI-MS and elemental analysis data. The activities of these analogues were evaluated against three organisms, and biological assays indicated that compounds 5f, 5h and 5u possessed better insecticidal activities against bean aphids (Aphis fabae) than the lead compound spirotetramat. The LC50 of 5f, 5h and 5u against bean aphids reached 0.42, 0.28 and 2.53 mg L(-1) respectively. Moreover, some compounds possessed comparable activities against carmine spider mite (Tetranychus cinnabarinus) and oriental armyworm (Mythimna sepatara) with spirotetramat. The structure-activity relationships (SARs) indicated that the flexible bridge at position C-4 of spirotetramat was important for its bioactivities, and the size of the group at position C-8 would have great influence on the activities. Furthermore, the log P values lower than 6.0 may be favourable for insecticidal activities., Conclusion: The present work demonstrates that some spirotetramat analogues can be used as potential lead compounds for developing novel insecticides, and preliminary SAR analysis would provide information for the utilisation of spirotetramat analogues as potential lipid biosynthesis inhibitors., (© 2012 Society of Chemical Industry.)

Laboratory and field studies were conducted to measure the effects of spirotetramat on life stages of California red scale, Aonidiella aurantii (Maskell), and a primary parasitoid, Aphytis melinus DeBach. Organophosphate-resistant and -susceptible populations responded similarly to spirotetramat, suggesting there is no cross-resistance between these insecticide classes. First and second instar male and female A. aurantii were 10- and 32-fold more susceptible to spirotetramat (LC50 = 0.1-0.2 ppm) compared with early third (LC50 = 1.5 ppm) and late third instar females (LC50 = 5.3 ppm). The LC99 value indicated that late stage third instar females would not be fully controlled by a field rate of spirotetramat; however, spirotetramat would reduce their fecundity by 89%. Field applications of spirotetramat in two water volumes and using two adjuvants (oil and a nonionic spray adjuvant) showed similar reduction in A. aurantii numbers, even though the higher water volume demonstrated more complete coverage. These data suggest that this foliarly applied systemic insecticide can be applied in as little as 2,340 liters/ha of water volume, minimizing application costs, and that the two adjuvants acted similarly. The endoparasitoid, A. melinus, was unaffected by the field rate of spirotetramat when it was applied to the host when the parasitoid was in the egg or larval stage. Adult A. melinus showed 2 wk of moderate reductions in survival when exposed to leaves with field-weathered residues. Spirotetramat is an integrated pest management compatible insecticide, effective in reducing A. aurantii stages and allowing survival of its primary parasitoid A. melinus.

Background: Pollinator exposure to pesticides is a concern in agricultural systems that depend on pollinators for crop production. However, not all pesticides elicit toxic effects, and response to a pesticide will vary depending on dose and exposure route. The effects of biopesticide formulations of Bacillus subtilis and Beauveria bassiana and of the tetramic acid insecticide spirotetramat on the common eastern bumblebee, Bombus impatiens, were evaluated. Microcolonies of bees were exposed to field-rate or lower concentrations, and data were collected over 60 days., Results: When ingested, field rates of spirotetramat caused high mortality after 10 days, and B. subtilis significantly reduced drone production, number of days to oviposition and number of days to drone emergence. Converse to effects observed following ingestion, topical applications of B. subtilis at concentrations less than the recommended field rate resulted in a hormetic response, with significantly increased drone production. Topical application of spirotetramat and oral or topical application of B. bassiana had no effects on bees., Conclusions: Spirotetramat and B. subtilis can induce adverse effects on B. impatiens, but hormetic effects following B. subtilis treatment can also occur, depending on exposure route. Additional experiments are required to determine whether similar toxic or hormetic effects occur under more realistic field conditions., (© 2012 Society of Chemical Industry.)

Introduction: Dogs are commonly used in cardiovascular drug safety assessment, and implanted telemetry models include subcutaneous or epicardial electrocardiogram (ECG) electrode placements. The purpose of this study was to determine the sensitivity of a canine telemetry model with intravenous ECG lead placement: the negative ECG lead (solid tip) inserted into the jugular vein and the positive lead sutured to the diaphragm. Reference drugs were administered to test the sensitivity to drug-induced changes., Methods: Twenty-four dogs were implanted with PCT or PCTP transmitters [Data Sciences International (DSI)]. Three reference drugs were administered: sotalol to eight PCT and milrinone to eight PCTP transmitter-implanted dogs. Twenty-four dogs received moxifloxacin (12 dogs/transmitter type). Telemetry data were collected for 25h and analyzed using double Latin squares for sotalol and milrinone data or a 4×4 or 3×6 parallel design for moxifloxacin data. Evaluated parameters were PR, QT, corrected QT (QTc), QRS, heart rate, left ventricular function, and hemodynamic data. Various correction factors for QTc interval were tested. Retrospective power analysis was performed to detect minimal absolute changes comparing a single to a double Latin square or the two parallel designs., Results: Expected changes on ECG and hemodynamic parameters were observed after administration of all reference drugs. The individual animal corrected QT (QTci) interval provided the optimal correction factor. Retrospective power analysis confirmed detection of smaller differences in double versus single Latin squares. Minimal detectable differences were smaller in both Latin squares compared to parallel designs, with smaller detectable differences in a 3×6 compared to a 4×4 parallel design., Discussion: The solid tip intravenous ECG lead configuration in dogs is a viable radiotelemetry model to detect drug-induced changes with high sensitivity. This model yields comparable signal quality and represents a refinement over epicardial ECG leads and allows for possible reduction in the number of animals if study design and size are selected based on needed assay sensitivity., (Copyright © 2013 Elsevier Inc. All rights reserved.)

Unlabelled: Abstract Purpose: To evaluate the antiproliferative and cytotoxic properties of moxifloxacin on cultured rat retinal ganglion cells (RGC5)., Materials and Methods: Rat retinal ganglion cells were exposed to various concentration of moxifloxacin (5-1500 μg/mL). For antiproliferative properties, the 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) test was performed. Cellular cytotoxicity was assessed by using the Live/Dead viability/cytotoxicity assay and analyzed by fluorescence microscopy after 24 and 72 h of incubation, respectively., Results: Neither cytotoxic nor antiproliferative effect of moxifloxacin was observed below 50 μg/mL on RGC5 cells after 24 and 72 h of incubation. At higher concentrations of moxifloxacin (150 μg/mL, 500 μg/mL, and 1500 μg/mL (p < 0.001)) the number of viable cells and the proliferation rate of RGC5 were significantly reduced., Conclusions: These results suggest a dose-dependent cytotoxic and antiproliferative effect of moxifloxacin on RGC5. Therefore, intracameral application of moxifloxacin should be used cautiously in patients with increased risk of retinal ganglion cells damage, particularly in glaucoma patients.

Acute toxicities of Tihan 175 O-TEQ, as well as its active ingredients flubendiamide and spirotetramat, and of Thionex 350 EC (active compound endosulfan) were measured for embryo-larval and juvenile stages of the African catfish Clarias gariepinus to assess risks of pesticide use in the cotton basin in Benin (West Africa). For embryo-larval stages, Tihan was more toxic (LC5048h 20 ppm) than Thionex (LC5048h 56 ppm), and flubendiamide was more toxic (LC5048h 2.0 ppm) than spirotetramat (LC5048h 8.44 ppm). All decreased hatching rates. Tihan and spirotetramat disturbed larval swimming coordination; flubendiamide induced tail cleavage. For juvenile fish, Thionex was more toxic (LC5096h 0.22 ppm) than Tihan (LC5096h 8.8 ppm), and flubendiamide (LC5096h 4.7 ppm) was more toxic than spirotetramat (LC5096h 6.0 ppm). Eggs were more resistant than juvenile fish to all tested pesticides except flubendiamide. Although Thionex was more toxic to juvenile fish, replacing Thionex with Tihan may be undesirable for survival of eggs and larvae.

Purpose: This study was carried out to determine the ocular pharmacokinetics, efficacy and potential endothelial toxicity of moxifloxacin (MF) after a single intracameral bolus injection of 500 µg/0.1 ml in a rabbit model., Materials and Methods: Forty-eight eyes of 24 New Zealand White Rabbits were separated into six groups, each including four rabbits. 0.1 ml of 0.5% intracameral moxifloxacin (500 µg) injection was injected to the right eyes and 0.1 ml of balanced salt solution to the left eyes (control). Aqueous humor (AH) and vitreous samples were collected at the 0.5th, 1st, 3rd, 6th, 12th and 24th hours from both eyes of group 1, 2, 3, 4, 5 and 6, respectively. MF concentrations were determined by high performance liquid chromatography. These were compared with the minimum inhibitory concentrations (MIC) and mutant prevention concentrations (MPC) for frequent endophthalmitis pathogens. Electron and light microscopical evaluation of the corneas were performed., Results: Moxifloxacin reaches higher concentration than the MIC of all common endophthalmitis pathogens in the AH and exceeds the mutant prevention concentration levels for Streptococcus pneumonia, Streptococcus viridans, flouroquinolone susceptible Coagulase-negative staphylococcus and flouroquinolone susceptible Staphylococcus aureus for 6 h. The half-life of moxifloxacin in the AH was 2.2 h. Electron and light microscopic evaluation revealed no noticeable sign of toxicity., Conclusions: Peroperative intracameral moxifloxacin injection for endophthalmitis prophylaxis is a safe and effective method in uncomplicated phacoemulsification surgery.

Natural enemies of the invasive pest Aphis glycines Matsumura can prevent its establishment and population growth. However, current A. glycines management practices include the application of broad-spectrum insecticides that affect pests and natural enemies that are present in the field at the time of application. An alternative is the use of selective insecticides that affect the targeted pest species, although having a reduced impact on the natural enemies. We tested the effects of esfenvalerate, spirotetramat, imidacloprid, and a combination of spirotetramat and imidacloprid on the natural enemies in soybean during the 2009 and 2010 field season. The natural enemy community that was tested differed significantly between 2009 and 2010 (F = 87.41; df = 1, 598; P < 0.0001). The most abundant natural enemy in 2009 was Harmonia axyridis (Pallas) (56.0%) and in 2010 was Orius insidiosus (Say) (41.0%). During 2009, the abundance of natural enemies did not vary between the broad-spectrum and selective insecticides; however, the abundance of natural enemies was reduced by all insecticide treatments when compared with the untreated control. In 2010, the selective insecticide imidacloprid had more natural enemies than the broad-spectrum insecticide. Although we did not observe a difference in the abundance of the total natural enemy community in 2009, we did observe more H. axyridis in plots treated with spirotetramat. In 2010, we observed more O. insidiosus in plots treated with imidacloprid. We suggest a couple of mechanisms to explain how the varying insecticides have different impacts on separate components of the natural enemy community.

A series of 2',3'-dideoxy-2',2'-difluoro-4'-azanucleosides of both pyrimidine and purine nucleobases were synthesized in an efficient manner starting from commercially available L-pyroglutamic acid via glycosylation of difluorinated pyrrolidine derivative 15. Several 4'-azanucleosides were prepared as a separable mixture of α- and β-anomers. The 6-chloropurine analogue was obtained as a mixture of N(7) and N(9) regioisomers and their structures were identified based on NOESY and HMBC spectral data. Among the 4'-azanucleosides tested as HIV-1 inhibitors in primary human lymphocytes, four compounds showed modest activity and the 5-fluorouracil analogue (18d) was found to be the most active compound (EC(50)=36.9μM) in this series. None of the compounds synthesized in this study demonstrated anti-HCV activity., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Background: When ophthalmic drug solutions are developed and clinically applied, their influence on corneal epithelium is an important issue. In the past, cells obtained by monolayer culture in vitro were used for evaluation of such influence. We recently created an experimental model of cell damage repair closer to the live body than conventional models by using layered sheets of cultured corneal epithelium. The present study was undertaken to evaluate the influence of ophthalmic moxifloxacin hydrochloride (MFLX) solution in comparison to that of ophthalmic levofloxacin (LVFX) solution using this model., Methods: Corneal epithelium cells were collected from corneal tissue specimens of white rabbits and subjected to air-lift culture to induce layering. Epithelial cell defects were created by a sponge soaked in 1 N aqueous sodium hydroxide. After removal of the sponge, either ophthalmic MFLX solution or ophthalmic LVFX solution was dropped onto the specimens three times daily (washed 1 min after each dose, followed by continuation of air-lifting culture). The percentage of the defective area repaired (percent defect repair) was evaluated. Each of the ophthalmic MFLX solution and the ophthalmic LVFX solution was used after the stock solution was diluted fourfold (1:4). Drug-free culture medium served as the negative control. Benzalconium chloride solution (BAC) 0.01% served as the positive control., Results: In the negative control group, complete repair of the defect with epithelial cells was seen 4 days after the start of treatment. In the positive control group, repair was suppressed. In the MFLX group and the LVFX group, the defect was repaired at each drug concentration, showing no significant difference from the negative control group. Thus, in this study using layered sheets of cultured corneal epithelium (a model closer to the living body than conventional models), the corneal epithelial defect was repaired in the ophthalmic MFLX solution treatment group and the ophthalmic LVFX solution treatment group to a degree similar to that in the negative control group., Conclusions: These results suggest that neither MLFX nor LVFX suppresses repair of corneal epithelial damage.

To determine the cytotoxicity of antibiotic eyedrops to ocular surface cells using a semi-quantitative method, a range of commercially available antibiotic eyedrops were assessed by using three corneal cell lines and one conjunctival cell line. All antibiotic solutions were free of benzalkonium chloride. Cell viability was determined by the MTT assay and neutral red assay following the exposure of cells to the undiluted, 2- and 10-fold diluted drugs for 10, 30, and 60 min. Toxicity was compared using % cell viability score (%CVS) . The tested eyedrops and values of %CVS50 and %CVS40/80 were Bestron(®) (cefmenoxime, 100, 94) , Panimycin(®) (dibekacin, 86, 58) , Noflo(®) (norfloxacin, 90, 50) , Cravit(®) (levofloxacin, 86, 46) , Tosfulo(®) (tosufloxacin, 57, -3) , and Vigamox(®) (moxifloxacin, 57, -6) . Cell viability markedly increased after dilution. For instance, cell viability assayed by MTT was > 80% for all the measurements in antibiotics diluted 10-fold, and the rate of the measurements showing > 80% cell viability decreased to 43% (31 out of 72 measurements) in the solutions diluted 2-fold. Of the drugs tested, Bestron(®) containing cefmenoxime showed the weakest toxicity. Vigamox(®) containing moxifloxacin and Tosuflo(®) containing tosufloxacin were more toxic when compared with the other antibiotics. CVS was useful for the comparison of the cytotoxicity of the drugs.

The field of ocular drug delivery is one of the interesting and challenging endeavors facing the pharmaceutical scientist. Novel approaches for ophthalmic drug delivery need to be established to increase the ocular bioavailability by overcoming the inherent drawbacks of conventional dosage forms. In situ hydrogels are instilled as drops into the eye and undergoes a sol-to-gel transition in the cul-de-sac, improved ocular bioavailability by increasing the duration of contact with corneal tissue, thereby reducing the frequency of administration. The purpose of the present work was to develop an ophthalmic drug delivery system using three different gelling agents with different mechanisms for in situ gelation of Moxifloxacin hydrochloride, a fluoroquinolone antibiotic. polyox (a pH-sensitive gelling agent), sodium alginate (an ion-sensitive gelling agent), and poloxamer (a temperature-sensitive gelling agent) were employed for the formation of in situ hydrogel along with HPMC K4M as viscofying agent, which increases the residence time of the drug in the ocular cavity. The promising formulations MF(4), MF(5), and MF(9) were evaluated for pH, drug content, in vitro gelation, in vitro drug release, in vivo drug release, ocular irritation, and stability. Percent drug content of 98.2, 98.76, and 99.43%; viscosity of 15.724 × 100, 16.108 × 100, and 15.213 × 100 cP at 20 rpm, cumulative percent release of 75.364, 74.081, and 71.752%, and C (max) of 1,164.16, 1,187.09, and 1,220.58 ng/ml was observed for formulation MF(4), MF(5), and MF(9), respectively. The developed formulations were therapeutically efficacious, stable, and non-irritant and provided sustained release of the drug over 8 h.

The earthworm Eisenia fetida is one of the most used species in standardized soil ecotoxicity tests. End points such as survival, growth, and reproduction are eco-toxicologically relevant but provide little mechanistic insight into toxicity pathways, especially at the molecular level. Here we apply a toxicogenomic approach to investigate the mode of action underlying the reversible neurotoxicity of hexanitrohexaazaisowurtzitane (CL-20), a cyclic nitroamine explosives compound. We developed an E. fetida-specific shotgun microarray targeting 15119 unique E. fetida transcripts. Using this array we profiled gene expression in E. fetida in response to exposure to CL-20. Eighteen earthworms were exposed for 6 days to 0.2 μg/cm(2) of CL-20 on filter paper, half of which were allowed to recover in a clean environment for 7 days. Nine vehicle control earthworms were sacrificed at days 6 and 13, separately. Electrophysiological measurements indicated that the conduction velocity of earthworm medial giant nerve fiber decreased significantly after 6-day exposure to CL-20, but was restored after 7 days of recovery. Total RNA was isolated from the four treatment groups including 6-day control, 6-day exposed, 13-day control, and 13-day exposed (i.e., 6-day exposure followed by 7-day recovery), and was hybridized to the 15K shotgun oligo array. Statistical and bioinformatic analyses suggest that CL-20 initiated neurotoxicity by noncompetitively blocking the ligand-gated GABA(A) receptor ion channel, leading to altered expression of genes involved in GABAergic, cholinergic, and Agrin-MuSK pathways. In the recovery phase, expression of affected genes returned to normality, possibly as a result of autophagy and CL-20 dissociation/metabolism. This study provides significant insights into potential mechanisms of CL-20-induced neurotoxicity and the recovery of earthworms from transient neurotoxicity stress.

The Bemisia tabaci Gennadius (Homoptera:Aleyrodidae) biotype complex is a key pest of several worldwide crops. The management and control of this pest has become difficult mainly due to its high reproductive rate and capacity to develop resistance to broad spectrum insecticides. In Argentina B. tabaci whitefly, causes economic losses in most areas of agricultural production. Eretmocerus mundus Mercet (Hymenoptera:Aphelinidae) is the most important parasitoid of B. tabaci and is commercialized as a biocontrol agent, mainly in Europe. Conservation of this biological control agent in Argentinean orchards requires the adoption of sustainable pest management practices due the negative impact of traditional pesticides on non-target organisms. Spirotetramat (Movento) belongs to a new class of pesticides that acts as a lipid biosynthesis inhibitor and claims to be selective towards natural enemies. The objectives of this work were 1) to evaluate the effectiveness of spirotetramat on eggs and nymphs of B. tabaci and 2) to determine the selectivity of spirotetramat towards E. mundus. Whitefly's eggs and nymphs (first nymphal settled instar) were exposed to the insecticide by foliar immersion whereas parasitoid adults (6 days old) were exposed to the insecticide by residual method for one hour, to simulate exposure of the parasitoid to the insecticide in the field. Lethal and sublethal effects of the insecticide were recorded daily. These preliminary studies have shown a high effectiveness of spirotetramat on the first nymphal instar of B. tabaci as well as a high selectivity for the pest in comparison to the parasitoid adults showing a low acute toxicity to them. These results suggest Movento could be included in Integrated Pest Management programs although more studies are required to complete its ecotoxicological profile.

Thirty novel derivatives of aza-cyclopenta[b]fluorene-1,9-dione were synthesized, and their cytotoxic activities were tested against HeLa, LS180, MCF-7, and Raji cancer cell lines by MTT assay. Two derivatives containing nitrofuryl moiety, including 10-(5-nitro-furan-2-yl)-2,3-dihydro-4-aza-cyclopenta[b]fluorene-1,9-dione (IC(50) range: 5.7-13.0 μm) and 10-(5-Nitro-furan-2-yl)-2,3,4,10-tetrahydro-4-aza-cyclopenta[b]fluorene-1,9-dione (IC(50) range: 3.6-20.2 μm), as well as 10-(2-Nitro-phenyl)-2,3,4,10-tetrahydro-4-aza-cyclopenta[b]fluorene-1,9-dione (IC(50) range: 3.1-27.1 μm) with nitrophenyl moiety on C10 position, were the most effective compounds. Furthermore, the effect of physiochemical descriptors on the cytotoxicity was evaluated by quantitative structure-activity relationship analysis. The quantitative structure-activity relationship results showed that molecular dipole moment, molar refractivity, fragment-based parameters, and some topological indices were influential on the cytotoxic effect. Finally, the good correlation that was found among cytotoxic data obtained from different cell lines may be an implication of a common cytotoxic mechanism in these cell lines. These findings provide useful structural information for the rational design and synthesis of efficient chemotherapeutic agents for treatment for cancer., (© 2011 John Wiley & Sons A/S.)

Long-term exposure to pharmacological agents can select for cells that overexpress efflux transporters. We previously showed that mouse J774 macrophages cultivated for a prolonged period of time with toxic concentrations of the fluoroquinolone ciprofloxacin overexpress the efflux transporter Mrp4 and display a reduced accumulation of this antibiotic, but no change in the accumulation of moxifloxacin, a closely related molecule (Antimicrob. Agents Chemother. [2006] 50, 1689-1695 and [2009] 53, 2410-2416). Because of this striking difference between the two fluoroquinolones, we have now examined the modifications in the expression of ABC efflux transporters induced by the prolonged exposure of J774 macrophages to high concentrations of moxifloxacin. The resulting cell line showed (i) no difference in the accumulation of moxifloxacin but an increased accumulation and decreased efflux of ciprofloxacin; (ii) an overexpression of the multidrug transporters Abcb1a (P-gp), Abcc2 (Mrp2) and Abcg2 (Bcrp1), and a decreased expression of Abcc4 (Mrp4). While P-gp and Bcrp1 were functional, they did not modify the cellular accumulation of fluoroquinolones. The data show that exposing cells to high concentrations of a drug that is not affected by active efflux can trigger a pleiotropic response leading to a modulation in the expression of several transporters. These changes, however, are not sufficient to protect cells against the toxicity that fluoroquinolones may exert at large concentrations. They could also cause unanticipated drug interactions in vivo, should the drug exposure grossly exceed what is anticipated from its current registered use., (Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.)

Objective: To compare the cytotoxic effects of preserved versus unpreserved commercially available ophthalmic preparations of fluoroquinolones on human keratocytes in vitro., Design: Experimental study., Methods: Human keratocytes in vitro were incubated for 15 or 60 minutes with commercially available preparations containing different types of fluoroquinolones, with or without benzalkonium chloride. We examined the morphologic aspects of the cultures by an inverted-phase contrast microscope and the release of cytoplasmic enzyme lactate dehydrogenase into the medium immediately or 24 hours after exposure to drugs., Results: Whereas preparations of ofloxacin, norfloxacin, and gatifloxacin, all containing benzalkonium chloride, and moxifloxacin, which is preservative-free, displayed various degrees of cytotoxicity in our model, the unpreserved monodose preparation of norfloxacin was virtually devoid of harmful effects under our experimental conditions., Conclusions: Our in vitro results indicated the cytotoxic role of preservatives in commercial preparations of fluoroquinolones and the relative nontoxicity of monodose unpreserved norfloxacin, even when keratocytes were incubated with this formulation for 6 hours., (Copyright © 2011 Canadian Ophthalmological Society. Published by Elsevier Inc. All rights reserved.)

Purpose: To compare the effect of three intracameral antibiotics, gentamicin (GM), gatifloxacin (GFLX), and moxifloxacin (MFLX), on the rabbit corneal endothelium., Methods: Twenty-four eyes from 18 rabbits were used. In the GM treatment group of 12 eyes, a dose of 20 mg/ml, 2 mg/ml, 200 μg/ml, or 20 μg/ml of GM was injected into the anterior chamber. In the GFLX and MFLX treatment groups were injected into the anterior chamber of three eyes. The central corneal thickness was measured. The eyes were then enucleated for observation under scanning electron microscopy., Results: Three days after the intracameral injection, a significant difference in central corneal thickness was found between the GM 20 mg/ml group and the control group (P < 0.05), but not between any other groups. The damage rate at the endothelial cell level was 67% in the GM 20 mg/ml group, 56% in the GM 2 mg/ml group, 33% in the GM 200 μg/ml group, 22% in the GM 20 μg/ml group, 22% in the GFLX group, and 0% in the MFLX group., Conclusions: Intracameral GFLX or MFLX was almost nontoxic to the rabbit corneal endothelium, in contrast to the toxic results of intracameral GM 20 and 2 mg/ml.

Background: Moxifloxacin (Vigamox), a 4th-generation fluoroquinolone, covers most isolates causing endophthalmitis. It is safe and effective for systemic and topical use; however, only very limited data are available on prophylactic intracameral administration to prevent endophthalmitis. This study investigated the safety of Vigamox for intracameral application in a cell-culture model., Methods: The endothelial toxicity of moxifloxacin (Vigamox) was evaluated in cultured human corneas. Primary human retinal pigment epithelium cells (RPEs), trabecular meshwork cells (TMCs), lens epithelium cells (LECs), and corneal endothelial cells (CECs) were treated with concentrations of Vigamox. Toxic effects were evaluated after 24 h (MTT assay and live-dead assay). By treating TMC, CEC, and RPE cells either with oxidative stress or tumor necrosis factor-alpha (TNF-a), lipopolysaccharide (LPS), and interleukin-6 (IL-6), the effects of moxifloxacin on cellular viability under conditions of inflammation were investigated., Results: No corneal endothelial toxicity could be detected after 30 days of treatment with moxifloxacin 500 microg/ml. Primary RPEs, TMCs, LECs, and CECs showed adverse effects on proliferation and viability only at concentrations higher than 150 microg/ml moxifloxacin. After preincubation with TNF-a, LPS, and IL-6 for 24 h and subsequent treatment with moxifloxacin at concentrations of 10-150 microg/ml for 24 h, no significant decrease in proliferation or viability was observed. H2O2 exposure did not increase cellular toxicity, Conclusion: Vigamox did not show significant toxicity on primary RPEs, TMCs, LECs, CECs, or human corneal endothelium at concentrations up to 150 microg/ml. The MIC90 of moxifloxacin for pathogens commonly encountered in endophthalmitis is known to be in the range of 0.25-2.5 microg/ml. Therefore, intracameral use of Vigamox at concentrations up to 150 microg/ml may be safe and effective for preventing endophthalmitis after intraocular surgery.

Purpose: The aim of this study was to evaluate the safety of moxifloxacin and voriconazole as a supplement in corneal storage media for porcine corneal endothelial cells., Methods: Twenty-eight eyes were divided into 4 groups. In the control group (the C group), corneal buttons were stored for 3 days in Optisol-GS. In the treatment group, the corneal buttons were preserved for 3 days in Optisol-GS mixed with 250 microg/mL moxifloxacin (M group), 100 microg/mL voriconazole (V group), and 250 microg/mL moxifloxacin plus 100 microg/mL voriconazole (MV group). We evaluated the samples via specular microscopy before and after 3 days of preservation. The mean changes of endothelial cell counts were compared among the 4 groups. Scanning electron microscopy was conducted after 3 days of preservation., Results: Before the preservation, the endothelial cell counts did not differ among the 4 groups (P > 0.05). After 3 days of preservation, the endothelial cell count in the MV group was the lowest among the 4 groups (P < 0.05). After 3 days of preservation, the rate of corneal endothelial cell loss in the M and V groups did not differ significantly from the control group (P > 0.05). The rate of endothelial cell loss in the MV group was significantly higher than that of the control group (P < 0.05). Scanning electron microscopy revealed a normal mosaic pattern for the C, V, and F groups, but hexagonality was not preserved in the MV group., Conclusion: Preservation in Optisol-GS mixed with moxifloxacin (250 microg/mL) plus voriconazole (100 microg/mL) induced significant toxicity on the endothelial cells in porcine corneas, when compared with the control group.