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1,3,5-Trimethylenebenzene (1,3,5-TMB), a 3-fold-symmetric triradical with a high-spin ground state, is an attractive platform for investigating the unique spin properties of π-conjugated triangular triradicals. Here, we report the on-surface synthesis of N-heterocyclic carbene (NHC)-derived 1,3,5-TMB (N-TMB) via surface-assisted C-C and C-N coupling reactions on Au(111). The chemical and electronic structures of N-TMB on the Au(111) surface are revealed with atomic precision using scanning tunneling microscopy and noncontact atomic force microscopy, combined with density functional theory (DFT) calculations. It is demonstrated that there is substantial charge transfer between N-TMB and the substrate, resulting in a positively charged N-TMB on Au(111). DFT calculations at the UB3LYP/def2-TZVP level of theory and multireference method, e.g., CASSCF/NEVPT2, indicate that N-TMB possesses a doublet ground state with reduced Cs symmetry in the gas phase, contrasting the quartet ground state of 1,3,5-TMB with D3h symmetry, and exhibits a doublet-quartet energy gap of -0.80 eV. The incorporation of NHC structures and the extended π-conjugation promote the spin-orbital overlaps in N-TMB, leading to Jahn-Teller distortion and the formation of a robust doublet state. Our results not only demonstrate the fabrication of polyradicals based on NHC but also shed light on the effect of NHC and π-conjugation on the electronic structure and spin coupling, which opens up new possibilities for precisely regulating the spin-spin exchange coupling of organic polyradicals.
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Cross-coupling reactions represent an indispensable tool in chemical synthesis. An intriguing challenge in this field is to achieve selective cross-coupling between two precursors with similar reactivity or, to the limit, the identical molecules. Here we report an unexpected dehydrobrominative cross-coupling between 1,3,5-tris(2-bromophenyl)benzene molecules on silver surfaces. Using scanning tunneling microscopy, we examine the reaction process at the single-molecular level, quantify the selectivity of the dehydrobrominative cross-coupling, and reveal the modulation of selectivity by substrate lattice-related catalytic activity or molecular assembly effect. Theoretical calculations indicate that the dehydrobrominative cross-coupling proceeds via regioselective C-H bond activation of debrominated TBPB and subsequent highly selective C-C coupling of the radical-based intermediates. The reaction kinetics plays an important role in the selectivity for the cross-coupling. This work not only expands the toolbox for chemical synthesis but also provides important mechanistic insights into the selectivity of coupling reactions on the surface.
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Herbivorous insects have evolved metabolic strategies to survive the challenges posed by plant secondary metabolites (SMs). This study reports an exploration of SMs present in pears, which serve as a defense against invasive Cydia pomonella and native Grapholita molesta and their counter-defense response. The feeding preferences of fruit borers are influenced by the softening of two pear varieties as they ripen. The content of SMs, such as quercetin and rutin, increases due to feeding by fruit borers. Notably, quercetin levels only increase after C. pomonella feeding. The consumption of SMs affects the growth of fruit borer population differently, potentially due to the activation of P450 genes by SMs. These two fruit borers are equipped with specific P450 enzymes that specialize in metabolizing quercetin and rutin, enabling them to adapt to these SMs in their host fruits. These findings provide valuable insights into the coevolution of plants and herbivorous insects.
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BACKGROUND: The sterile insect technique (SIT) has proven to be an effective approach in managing the population of major invasive pests. Our previous studies showed that irradiation of Cydia pomonella males at a dosage of 366 Gy X-rays resulted in complete sterility. However, the mating competitiveness of sterilized males is significantly compromised, which can be attributed to a decline in their ability to fly. RESULTS: In this study, we examined the flight patterns of both male and female adults of C. pomonella. The results revealed significant variations in the average flight speed of both genders at different stages of maturity, with females displaying longer flight duration and covering greater distances. Effect of irradiation on the flight performance of 3-day-old male moths was further evaluated, as they demonstrated the longest flight distance. The findings indicated a significant decrease in flight distance, duration, and average speed, due to wing deformities caused by irradiation, which also limited the dispersal distance of moths in orchards, as indicated by the mark-and-recapture assay. Reverse-transcription quantitative polymerase chain reaction analysis revealed a down-regulation of flight-related genes such as Flightin, myosin heavy chain, and Distal-less following radiation exposure. CONCLUSION: These findings demonstrate that X-ray irradiation at a radiation dose of 366 Gy has a detrimental effect on the flight ability of male C. pomonella adults. These insights not only contribute to a better understanding of how radiation sterilization diminishes the mating competitiveness of male moths, but also aid in the development and improvement of SIT practices for the effective control of C. pomonella. © 2023 Society of Chemical Industry.
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Infertilidad , Mariposas Nocturnas , Animales , Femenino , Masculino , Rayos XRESUMEN
While previous studies have reported G protein-coupled receptor (GPCR)-mediated insecticide resistance in various arthropods, the understanding of GPCR-associated resistance mechanisms in Cydia pomonella remains limited. In this study, a total of 95 CpGPCR genes categorized into four families were identified in C. pomonella. Results revealed high expression levels of the majority of the CpGPCRs during the first larval stage and in the head of C. pomonella. Exposure to lambda-cyhalothrin significantly increased the expression of 15 CpGPCRs, including CpGPCR70, which is highly expressed in all larval stages and shows the highest expression in the midgut. RNA interference (RNAi) demonstrated that downregulation of CpGPCR70 leads to reduced expression of key resistance-related genes and a decreased tolerance of larvae to lambda-cyhalothrin. These findings indicate that CpGPCR70 plays a crucial role in regulating the expression of detoxifying genes involved in lambda-cyhalothrin resistance, offering valuable insights for the development of more effective pest control strategies.
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Insecticidas , Mariposas Nocturnas , Piretrinas , Humanos , Animales , Piretrinas/farmacología , Piretrinas/metabolismo , Mariposas Nocturnas/metabolismo , Nitrilos/farmacología , Nitrilos/metabolismo , Larva , Insecticidas/farmacología , Insecticidas/metabolismoRESUMEN
The advantageous characteristics of invasive pests, particularly their ability to reproduce and adapt to the environment, have been observed. However, it remains unclear what specific inherent superiority enables fruit pests to successfully invade and dominate in interactions with other species. In this study, we report that Cydia pomonella (Linnaeus), a notorious invasive pest of pome fruits and walnuts globally, employs unique reproductive strategies in response to quercetin, a plant compound in host fruits. By monitoring adult dynamics and fruit infestation rates, we observed a competitive relationship between C. pomonella and the native species Grapholita molesta (Busck). C. pomonella was able to occupy vacant niches to ensure its population growth. We also found that quercetin had different effects on the reproductive capacity and population growth of C. pomonella and G. molesta. While quercetin stimulated the fecundity and population growth of G. molesta, it inhibited C. pomonella. However, C. pomonella was able to rapidly increase its population after exposure to quercetin by adopting an 'accelerated burst' of oviposition strategy, with each individual making a greater reproductive contribution compared to the control. We further demonstrated that the effect of quercetin on oviposition is regulated by the juvenile hormone (JH) signaling pathway in C. pomonella, allowing it to prioritize survival. The enhanced reproductive fitness of G. molesta in response to quercetin is attributed to the regulation of JH titers and key genes such as Met and Kr-h1, which in turn up-regulate reproduction-related genes Vg and VgR. In contrast, C. pomonella is inhibited. These findings shed light on the mechanisms interspecific competition and help to improve our understanding of the global spread of C. pomonella, which can be attributed to its inherent superiority in terms of reproductive strategy.
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Mariposas Nocturnas , Animales , Femenino , Quercetina/farmacología , Hormonas Juveniles/farmacología , Oviposición , Frutas , Transducción de SeñalRESUMEN
Aryl hydrocarbon receptor (AhR) enhances insect resistance to insecticides by regulating the detoxification network. Our previous studies have confirmed that overexpressions of cytochrome P450 monooxygenases (P450s) and glutathione S-transferases (GSTs) are involved in lambda-cyhalothrin resistance in Cydia pomonella. Here, we report that CpAhR regulates the expression of GST and P450 genes, thus conferring resistance. Expression patterns indicated that the expression of CpAhR was highly induced by lambda-cyhalothrin exposure and upregulated in a lambda-cyhalothrin-resistant population. RNA interference (RNAi) of CpAhR decreases the expression of key resistance-related genes (CpGSTe3, CpCYP9A121, and CpCYP9A122) and the activity of the GST enzyme, reducing the tolerance to lambda-cyhalothrin. Furthermore, ß-naphthoflavone, a novel agonist of AhR, was first proven to be effective in increasing CpAhR expression and larval tolerance to lambda-cyhalothrin. These results demonstrate that CpAhR regulates the expression of key detoxifying genes and GST activity, resulting in the development of resistance to lambda-cyhalothrin in C. pomonella.
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Insecticidas , Mariposas Nocturnas , Piretrinas , Animales , Receptores de Hidrocarburo de Aril/genética , Piretrinas/farmacología , Piretrinas/metabolismo , Insecticidas/farmacología , Insecticidas/metabolismo , Mariposas Nocturnas/metabolismo , Nitrilos/farmacología , Nitrilos/metabolismo , Transferasas , Glutatión , Resistencia a los Insecticidas/genéticaRESUMEN
The codling moth Cydia pomonella (Lepidoptera: Tortricidae) is a major invasive pest of pome fruits and walnuts worldwide. Lambda-cyhalothrin (LCT) and abamectin (AM) have been frequently used in C. pomonella control, but control of this pest is very difficult because shortly after hatching, larvae of this insect bore tunnels and hide inside host plant fruit. In this study, a simulated field spray bioassay method was developed against neonate larvae of C. pomonella and concentration-response bioassays were conducted to evaluate the susceptibility of the neonate larvae to LCT and AM. Exposure of neonate larvae to sublethal concentration (LC30) of LCT or AM significantly reduced the survival rate of larvae (4th and 5th instars), lowered the mean weight of larvae and pupae, and decreased the daily maximal number of eggs laid and the total number of eggs laid (fecundity) per female. The sublethal effects, including reduced body mass, mean fecundity and net reproductive rate, extended mean generation time, and shortened oviposition period, were also found in transgenerational offspring. Furthermore, the transgenerational maternal effects were more obvious for AM than LCT, in comparison to the control. Additionally, the estimated population size was decreased by exposure to LC30 of LCT and AM, and the observed reduction of fecundity and population size within and across generations was likely the result of the downregulation of the reproduction-related vitellogenin gene (CpVg) after exposure to LC30 of LCT and AM. These results provide a better understanding of the overall effects of LCT and AM on C. pomonella and the transgenerational effects which should be taken into consideration when using insecticides in order to control C. pomonella.
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Insecticidas , Mariposas Nocturnas , Piretrinas , Animales , Femenino , Piretrinas/toxicidad , Larva , Insecticidas/toxicidad , ReproducciónRESUMEN
BACKGROUND: The evolution of insect resistance to pesticides poses a continuing threat to sustainable pest management. While much is known about the molecular mechanisms that confer resistance in model insects and few agricultural pests, far less is known about fruit pests. Field-evolved resistance to synthetic insecticides such as lambda-cyhalothrin has been widely documented in Cydia pomonella, a major invasive pest of pome fruit worldwide, and the increased production of cytochrome P450 monooxygenases (P450s) has been linked to resistance in field-evolved resistant populations. However, the underlying molecular mechanisms of P450-mediated insecticide resistance remain largely unknown. RESULTS: Here we found that functional redundancy and preference of metabolism by P450s genes in the CYP9A subfamily confer resistance to lambda-cyhalothrin in Cydia pomonella. A total of four CYP9A genes, including CYP9A61, CYP9A120, CYP9A121, and CYP9A122, were identified from Cydia pomonella. Among these, CYP9A120, CYP9A121, and CYP9A122 were predominantly expressed in the midgut of larvae. The expression levels of these P450 genes were significantly induced by a lethal dose that would kill 10% (LD10 ) of lambda-cyhalothrin and were overexpressed in a field-evolved lambda-cyhalothrin resistant population. Knockdown of CYP9A120 and CYP9A121 by RNA-mediated interference (RNAi) increased the susceptibility of larvae to lambda-cyhalothrin. In vitro assays demonstrated that recombinant P450s expressed in Sf9 cells can metabolize lambda-cyhalothrin, but with functional redundancy and divergence through regioselectivity of metabolism. CYP9A121 preferred to convert lambda-cyhalothrin to 2'-hydroxy-lambda-cyhalothrin, whereas CYP9A122 only generated 4'-hydroxy metabolite of lambda-cyhalothrin. Although possesses a relatively low metabolic capability, CYP9A120 balanced catalytic competence to generate both 2'- and 4'-metabolites. CONCLUSION: Collectively, these results reveal that metabolic functional redundancy of three members of the CYP9A subfamily leads to P450-mediated lambda-cyhalothrin resistance in Cydia pomonella, thus representing a potential adaptive evolutionary strategy during its worldwide expansion. © 2022 Society of Chemical Industry.
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Insecticidas , Mariposas Nocturnas , Piretrinas , Animales , Piretrinas/metabolismo , Insecticidas/metabolismo , Mariposas Nocturnas/genética , Nitrilos/metabolismo , Larva/metabolismo , Resistencia a los Insecticidas/genéticaRESUMEN
The codling moth Cydia pomonella is a major pest of global significance impacting pome fruits and walnuts. It threatens the apple industry in the Loess Plateau and Bohai Bay in China. Sterile insect technique (SIT) could overcome the limitations set by environmentally compatible area-wide integrated pest management (AW-IPM) approaches such as mating disruption and attract-kill that are difficult to suppress in a high-density pest population, as well as the development of insecticide resistance. In this study, we investigated the effects of X-ray irradiation (183, 366, 549 Gy) on the fecundity and fertility of a laboratory strain of C. pomonella, using a newly developed irradiator, to evaluate the possibility of X-rays as a replacement for Cobalt60 (60Co-γ) and the expanded future role of this approach in codling moth control. Results show that the 8th-day is the optimal age for irradiation of male pupae. The fecundity decreased significantly as the dosage of radiation increased. The mating ratio and mating number were not influenced. However, treated females were sub-sterile at a radiation dose of 183 Gy (20.93%), and were almost 100% sterile at a radiation dose of 366 Gy or higher. Although exposure to a radiation dose of 366 Gy resulted in a significant reduction in the mating competitiveness of male moths, our radiation biology results suggest that this new generation of X-ray irradiator has potential applications in SIT programs for future codling moth control.
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Infertilidad , Mariposas Nocturnas , Femenino , Masculino , Animales , Rayos X , Rayos gamma , FertilidadRESUMEN
Halogen-mediated interactions play an important role in molecular recognition and crystallization in many chemical and biological systems, whereas their effect on homochiral versus heterochiral recognition and crystallization has rarely been explored. Here we demonstrate the evolution of Brâ¯Br contacts in chiral recognition during 2D crystallization. On Ag(100), type I contacts prevail at low coverage and lead to homochiral recognition and the formation of 2D conglomerates; whereas type II contacts mediating heterochiral recognition are suppressed at medium coverage and appear in the racemates induced by structural transitions at high coverage. On Ag(111), type I contacts dominate the 2D crystallization and generate 2D conglomerates exclusively. DFT calculations suggest that the energy difference between type I and type II contacts is reversed upon adsorption due to the substrate induced mismatch energy penalty. This result provides fundamental understanding of halogen-mediated interactions in molecular recognition and crystallization on surface.
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Halógenos , Adsorción , Cristalización , EstereoisomerismoRESUMEN
Aromatic ring fusion to porphyrins and their derivatives represents an attractive route to tune the molecular conjugation and thus expand their functionalities. Here, we report the expansion of the aromatic π-system of palladium tetraphenyltetrabenzoporphyrins (Pd-TPTBP) via surface-assisted γ-ortho cyclodehydrogenation on Ag(111). The chemical transformation of Pd-TPTBP into different products at an elevated temperature of 600 K was revealed at the single-molecule level using bond-resolved scanning tunneling microscopy with a CO-functionalized tip. We captured a series of γ-ortho cyclodehydrogenation products, wherein the maximum extent to which the reaction can progress is associated with 7-fold C-C formation to afford nearly planar γ-ortho fused porphyrins with 66 conjugated π-electrons. In addition, a small number of molecules undergo C-C bond dissociation of meso-phenyl at elevated temperature, producing fully planar γ-ortho fused products lacking one or two phenyl moieties. Scanning tunneling spectroscopy measurements and DFT calculations suggest the electronic gap of the γ-ortho fused porphyrin decreases compared to that of the precursor. The HOMO and LUMO of the planar γ-ortho fused products are localized on the partially fused benzo moieties and the meso-position, respectively.
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BACKGROUND: Spodoptera frugiperda has spread to Africa, Asia, and Oceania, posing a serious threat to global agriculture. We estimated the appropriate dose of X-ray sterilization for S. frugiperda using an X-ray irradiation instrument to investigate environmentally acceptable control techniques, laying the framework for future applications of sterile insect technology (SIT) to manage the pest environmentally-friendly. RESULTS: This study is the first to investigate the effects of X-ray irradiation on the growth, development, survival, reproduction, and flight of S. frugiperda. The results showed that irradiation with 50-400 Gy had no significant effect on pupal eclosion, but females were more sensitive than males in terms of reproductive parameters, especially when doses of radiation were > 350 Gy. After irradiation with a sub-sterilizing dose of 250 Gy, the parental sterility rate was > 85%, and the sterility traits could be passed on to their offspring, resulting in a continuous decrease in the population of F1 and F2 generations. CONCLUSION: Our laboratory experiments theoretically confirmed the feasibility of SIT for controlling S. frugiperda in the field using X-ray radiation. This study provides a theoretical basis for future regional pest management strategies. © 2022 Society of Chemical Industry.
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Infertilidad , Especies Introducidas , Spodoptera , Animales , Femenino , Control de Insectos/métodos , Larva/efectos de la radiación , Masculino , Pupa/efectos de la radiación , Spodoptera/efectos de la radiación , Rayos XRESUMEN
Pest management is mostly accomplished by the use of insecticides. However, the overuse of insecticides has led to the development of resistance. Glutathione S-transferases (GSTs) are vital detoxification enzymes involved in insecticide resistance in insects. In this study, we report the involvement of GSTs in insecticide resistance to lambda-cyhalothrin in Cydia pomonella, a globally quarantined fruit pest. A total of 25 GST, including 22 cytosolic genes and 3 microsomal genes, are identified from the genome database of C. pomonella. These cytosolic genes are further classified into six classes, including four in delta, eight in epsilon, three in omega, three in sigma, one in theta, and one in zeta class, as well as two unclassified genes. The real-time quantitative polymerase chain reaction (RT-qPCR) shows that the majority of these genes are mainly expressed throughout the larval stage and in the midgut of the fourth-instar larvae. Exposure to an LD10 dose of lambda-cyhalothrin resulted in the upregulation of 17 GST genes. Moreover, mRNA levels of most GST genes, with the exception of CpGSTe6, CpGSTd2, CpGSTd4, and CpGSTz1, are considerably higher in a lambda-cyhalothrin-resistant population (ZW_R) than those of susceptible strains. Recombinant CpGSTd1, CpGSTd3, CpGSTe3, and CpGSTs2 can bind and metabolize lambda-cyhalothrin, with the highest metabolic rate observed for CpGSTd3 but no metabolite(s) was detected, supporting the role of GSTs in sequestration of lambda-cyhalothrin. Molecular dynamics simulation analysis indicates that key residues of hydrophobic pocket-derived lipophilic energy S(lipo) interactions with a hydrophobic pharmacophore of lambda-cyhalothrin are crucial for metabolism by CpGSTd3 and further lead to resistance. Our study is the first to experimentally confirm the involvement of GSTs in lambda-cyhalothrin resistance via sequestration and provides new insights into resistance management in C. pomonella.
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Insecticidas , Mariposas Nocturnas , Piretrinas , Animales , Glutatión Transferasa/metabolismo , Resistencia a los Insecticidas/genética , Insecticidas/metabolismo , Insecticidas/farmacología , Mariposas Nocturnas/genética , Nitrilos/metabolismo , Nitrilos/farmacología , Piretrinas/metabolismo , Piretrinas/farmacologíaRESUMEN
The codling moth, Cydia pomonella (Lepidoptera: Tortricidae) is a major pest of pome fruit and walnuts worldwide. Although environmentally compatible integrated control strategies, such as mating disruption, attract-kill strategy, and sterile insect technique have been conducted for management of this notorious pest, effects to control of codling moth have mainly relied on insecticides. In consequence, different levels of insecticide resistance towards organophosphates, neonicotinoids, hydrazines, benzoylureas, pyrethroids, diamides, spinosyns, avermectins, JH mimics, carbamates, oxadiazines and C. pomonella granulovirus (CpGVs) have developed in codling moth in different countries and areas. Both metabolic and target-site mechanisms conferring resistance have been revealed in the codling moth. In this review, we summarize the current global status of insecticide resistance, the biochemical and molecular mechanisms involved, and the implications for resistance management.
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Insecticidas , Mariposas Nocturnas , Piretrinas , Animales , Resistencia a los Insecticidas , Insecticidas/farmacología , NeonicotinoidesRESUMEN
To investigate effectsof Yangyinyiqi Mixture on pulmonary fibrosis caused by bleomycin. SD ratswere divided randomly into: model group(distilled water,1 mL·0.1 kg-1), dexamethasone acetate group (dexamethasone acetate, the dosage was reduced gradually), low-dose group (Yangyinyiqi Mixture, 11 g·kg-1), moderate-dose group (Yangyinyiqi Mixture, 22 g·kg-1), high-dose group (Yangyinyiqi Mixture, 44 g·kg-1) and control group (distilled water, 1 mL·0.1 kg-1). Yangyinyiqi Mixture and dexamethasone acetate were intragastrically administrated. Lung tissue was collected for histopathological examination. Compared with control group, collagen markedly increased and HYP content significantly increased on 7th day in model group (p<0.01). On 28th day, collagen was diffusely deposited, alveolar was destroyed, and HYP content significantly increased (p<0.01). Compared with model group, bleomycin-induced suffering injury caused MMP-9 expression levels to rapidly increase (7and 14 days, p<0.01). TIMP-1 markedly increased (7and 14 days, p<0.01) and stayed at a high level to28th day. Yangyinyiqi Mixture exerted an effect against pulmonary fibrosis, which could involved prevention of collagen deposition through inhibitingMMP-9 and TIMP-1 expression.
El trabajo investiga los efectos de la mezcla Yangyinyiqi sobre la fibrosis pulmonary causada por bleomicina. Ratas SD se dividieron aleatoriamente en: grupo modelo (agua destilada, 1 mL·0.1 kg-1), grupo acetate de dexametasona (acetate de dexametasona, la dosis se redujo gradualmente), grupo de dosis baja (mezcla Yangyinyiqi, 11 g·kg-1), grupo de dosis moderada (mezcla Yangyinyiqi, 22 g·kg-1), grupo de dosis alta (mezcla Yangyinyiqi, 44 g·kg-1) y grupo control (agua destilada, 1 Ml·0.1 kg-1). La mezcla de Yangyinyiqi y el acetate de dexametasona se administraron por vía intragástrica. Se recolectó tejido pulmonary para examen histopatológico. En comparación con el grupo control, el colágeno aumentó notablemente y el contenido de HYP aumentó significativamente el séptimo día en el grupo modelo (p<0.01). El día 28, el colágeno se depositó difusamente, se produjo destrucción alveolar y el contenido de HYP aumento significativamente (p<0.01). En comparación con el grupo modelo, la lesión inducida por bleomicina causó que los niveles de expression de MMP-9 aumentaron rápidamente (7 y 14 días, p<0.01). TIMP-1 aumentó notablemente (7 y 14 días, p<0.01) y se mantuvo en un nivel alto hasta el día 28. La mezcla Yangyinyiqi ejerció un efecto contra la fibrosis pulmonary, lo que podría implicar la prevención del deposito de colágenio mediante la inhibición de la expression de MMP-9 y TIMP-1.
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Animales , Masculino , Ratas , Fibrosis Pulmonar/tratamiento farmacológico , Medicamentos Herbarios Chinos/administración & dosificación , Inhibidores Tisulares de Metaloproteinasas/metabolismo , Metaloproteinasa 9 de la Matriz/metabolismo , Bleomicina , Dexametasona/administración & dosificación , Western Blotting , Ratas Sprague-Dawley , Metaloproteinasa 1 de la Matriz , Modelos Animales de Enfermedad , Hidroxiprolina/análisisRESUMEN
The codling moth, Cydia pomonella (L.), is a quarantine pest of global significance impacting pome fruits and walnuts. It has evolved resistance to many commonly used insecticides including λ-cyhalothrin. Glutathione S-transferases (GSTs) are multifunctional enzymes playing a crucial role in the detoxification of insecticides in insects. However, the role of specific GST gene in λ-cyhalothrin resistance in C. pomonella is unclear. In this study, we identified three sigma-class genes (CpGSTs1, CpGSTs2, and CpGSTs3). These genes were ubiquitously expressed at all developmental stages, and of these, the expression level of CpGSTs2 in the larval stage was significantly higher than in the egg, pupal, and adult stages. Moreover, CpGSTs2 was predominantly expressed in the fat body while lower levels in the cuticle. In addition to exposure of larvae to LD10 of λ-cyhalothrin elevating the expression level of CpGSTs2, mRNA levels of CpGSTs2 in a field population (ZW_R) from northeast China, which has developed moderate level resistance to λ-cyhalothrin, was significantly higher than that of susceptible strains. In vitro inhibition assays demonstrated that λ-cyhalothrin inhibited the conjugating activities of recombinant CpGSTs2, and metabolic assays indicated that λ-cyhalothrin could be depleted by recombinant CpGSTs2. These results bring evidence for the involvement of CpGSTs2 in C. pomonella in resistance to λ-cyhalothrin.
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Glutatión Transferasa/metabolismo , Proteínas de Insectos/metabolismo , Resistencia a los Insecticidas , Insecticidas/metabolismo , Mariposas Nocturnas/efectos de los fármacos , Mariposas Nocturnas/enzimología , Nitrilos/metabolismo , Piretrinas/metabolismo , Animales , Glutatión Transferasa/química , Glutatión Transferasa/genética , Proteínas de Insectos/química , Proteínas de Insectos/genética , Insecticidas/química , Insecticidas/farmacología , Larva/efectos de los fármacos , Larva/genética , Larva/crecimiento & desarrollo , Larva/metabolismo , Mariposas Nocturnas/genética , Mariposas Nocturnas/crecimiento & desarrollo , Nitrilos/farmacología , Piretrinas/farmacologíaRESUMEN
Analysis of the glutathione S-transferase (GST) gene expression in an insecticide-resistant strain of Cydia pomonella using real-time quantitative polymerase chain reaction is a key step toward more mechanism studies that require suitable reference genes with stable expression. Here, nine commonly used reference genes were selected, and their expression stabilities were analyzed. Results showed that EF-1α was the most stable reference gene in all of the experimental sets. The combinations of EF-1α and 18S, EF-1α and RPL12, and EF-1α and GAPDH were sufficient for normalization of gene expression analysis accurately in developmental stages, tissues, and larvae exposed to sublethal dose of λ-cyhalothrin, respectively. Additionally, the suitability of particular reference genes was verified by analyzing the spatiotemporal and insecticide-induced expression profiles of CpGSTe3, CpGSTd3, and CpGSTd4, which were overexpressed in a λ-cyhalothrin-resistant population from northeast China. These genes were used to confer the practicability of reference genes chosen in this study.
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Glutatión Transferasa/genética , Proteínas de Insectos/genética , Resistencia a los Insecticidas , Insecticidas/farmacología , Mariposas Nocturnas/efectos de los fármacos , Nitrilos/farmacología , Piretrinas/farmacología , Animales , China , Perfilación de la Expresión Génica , Glutatión Transferasa/metabolismo , Proteínas de Insectos/metabolismo , Mariposas Nocturnas/enzimología , Mariposas Nocturnas/genéticaRESUMEN
2D extended organic cocrystals were constructed using 1,4-diiodotetrafluorobenzene and aromatic aldehydes via IOaldehyde halogen bonds on an Au(111) surface. The competition and synergy of halogen bonds and hydrogen bonds in 2D co-crystallization were revealed by scanning tunneling microscopy.
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AIMS AND OBJECTIVES: To explore the consistency of pain intensity and pain location assessed by nurses and patients in gynaecology undergoing enhanced recovery after surgery pathway. BACKGROUND: Several studies have shown that clinical nurses' assessment of patients' pain is not always accurate. Little is known about the accuracy of nurses' pain assessments for gynaecological patients. Postoperative pain assessment and management is an essential part of enhanced recovery after surgery. DESIGN: Comparative cross-sectional study. METHODS: A total of 160 patients were recruited and only 85 patients and 17 nurses participated. Patients and nurses recorded pain scores (using an 11-point Numeric Rating Scale) and pain location (incision pain, surgical area pain in the abdominal cavity, other pain or no pain) on Pain Assessment Forms at 4 hr after surgery and on the first and second postoperative days. We used the STROBE guidelines to report our study. RESULTS: The patients' pain score was higher than that of nurses from 4 hr to second day after laparoscopic surgery at rest. The pain scores of both nurses and patients decreased over this period of time. All the intraclass correlation coefficients were between 0.214-0.296. At the three time points, surgical area pain in the abdominal cavity and abdominal incision pain were the main pain areas. All the kappa coefficients were between 0.164-0.255. CONCLUSIONS: The consistency of postoperative pain assessment about pain score and pain location between nurses and patients was not high. We should attach importance to systematic pain assessment, and more detailed enhanced recovery after surgery pathways should be developed about pain assessment. RELEVANCE TO CLINICAL PRACTICE: Continuing education for nurses regarding pain assessment is necessary. Nurses should accept the patient's self-reported pain. There should be a step that gives more time for pain assessment in enhanced recovery after surgery pathways.