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1.
Anal Chem ; 96(31): 12883-12891, 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39056433

RESUMO

Qualitative and quantitative analysis of Raman spectroscopy is a widely used nondestructive analytical technique in many fields. It utilizes the Raman scattering effect of lasers to obtain molecular vibration information on samples. By comparison with the Raman spectra of standard substances, qualitative and quantitative analyses can be achieved on unknown samples. However, current Raman spectroscopy analysis algorithms still have many drawbacks. They struggled to handle quantitative analysis between different instruments. Their prediction accuracy for concentration is generally low, with poor robustness. Therefore, this study addresses these deficiencies by designing the cross instrument-sparse Bayesian learning (CI-SBL) Raman spectroscopy analysis algorithm. CI-SBL can facilitate spectroscopic analysis between different instruments through the cross instrument module. CI-SBL converts data from portable instruments into data from scientific instruments, with high similarity between the converted spectrum and the spectrum from the scientific instruments reaching 98.6%. The similarity between the raw portable instrument spectrum and the scientific instrument spectrum is often lower than 90%. The cross instrument effect of the CI-SBL is remarkable. Moreover, CI-SBL employs sparse Bayesian learning (SBL) as the core module for analysis. Through multiple iterations, the SBL algorithm effectively identified various components within mixtures. In experiments, CI-SBL can achieve a qualitative accuracy of 100% for the majority of binary and multicomponent mixtures. On the other hand, the previous Raman spectroscopy analysis algorithms predominantly yield a qualitative accuracy below 80% for the same data. Additionally, CI-SBL incorporates a quantitative module to calculate the concentration of each component within the mixed samples. In the experiment, the quantification error for all substances was below 3%, with the majority of the substances exhibiting an error of approximately 1%. These experimental results illustrate that CI-SBL significantly enhances the accuracy of qualitative judgment of mixture spectra and the prediction of mixture concentrations compared with previous Raman spectroscopy analysis algorithms. Furthermore, the cross instrument module of CI-SBL allows for a flexible handling of data acquired from different instruments.

2.
J Antimicrob Chemother ; 79(4): 820-825, 2024 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-38366379

RESUMO

OBJECTIVES: To describe the pharmacokinetics/pharmacodynamics (PK/PD) of ceftazidime/avibactam in critically ill patients with CNS infections. METHODS: A prospective study of critically ill patients with CNS infections who were treated with ceftazidime/avibactam and the steady-state concentration (Css) of ceftazidime/avibactam in serum and/or CSF was conducted between August 2020 and May 2023. The relationship between PK/PD goal achievement, microbial eradication and the clinical efficacy of ceftazidime/avibactam was evaluated. RESULTS: Seven patients were finally included. The ceftazidime/avibactam target attainment in plasma was optimal for three, quasi-optimal for one and suboptimal for three. In three patients with CSF drug concentrations measured, ceftazidime/avibactam target attainment in CSF was 100% (3/3), which was optimal. The AUCCSF/serum values were 0.59, 0.44 and 0.35 for ceftazidime and 0.57, 0.53 and 0.51 for avibactam. Of the seven patients, 100% (7/7) were treated effectively, 71.4% (5/7) achieved microbiological eradication, 85.7% (6/7) survived and 14.3% (1/7) did not survive. CONCLUSIONS: The limited clinical data suggest that ceftazidime/avibactam is effective in the treatment of CNS infections caused by MDR Gram-negative bacilli (MDR-GNB), can achieve the ideal drug concentration of CSF, and has good blood-brain barrier penetration.


Assuntos
Ceftazidima , Infecções do Sistema Nervoso Central , Humanos , Ceftazidima/farmacologia , Ceftazidima/uso terapêutico , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Estudos Prospectivos , Carbapenêmicos , Estado Terminal , Compostos Azabicíclicos/farmacologia , Compostos Azabicíclicos/uso terapêutico , Combinação de Medicamentos , Infecções do Sistema Nervoso Central/tratamento farmacológico , Testes de Sensibilidade Microbiana
3.
Phys Chem Chem Phys ; 26(22): 16287-16295, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38804814

RESUMO

A phenomenon known as plasmon resonance constitutes a unique optical effect that can induce an enhancement in localized electromagnetic fields, resulting in a substantial increase in the electromagnetic field intensity surrounding metallic nanostructures. In this work, the coupling effect of excitation of surface plasmon polaritons and local surface plasmons in nanoparticles is deeply studied under the background of nanoparticles/one-dimension grating composite structures through grating matching. By employing finite-difference time-domain simulations as our methodological approach, we discern gratings with a periodicity of 1.5 µm support surface plasmon bound states between the gratings. Furthermore, the modulation of SPs along the vertical sidewalls of the grating due to standing wave effects exhibits oscillatory behavior with varying grating heights. Experimental results obtained from the nanoparticle/grating composite SERS substrate validate theoretical predictions, demonstrating higher enhanced Raman signals at 633 nm compared to 532 nm. Remarkably, this structure exhibits good performance, with R6G detection sensitivity down to concentrations as low as 10-10 M and mapping achieving a relative standard deviation of 7.79%, underscoring its uniformity and capability of electromagnetic field enhancement.

4.
Eur J Clin Pharmacol ; 80(5): 737-746, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38353692

RESUMO

PURPOSE: To analyze the risk factors influencing the development of cefoperazone-induced coagulopathy in critically ill patients and determine the threshold of serum trough concentration. METHODS: A retrospective case-control study was conducted in the intensive care unit patients treated with cefoperazone, and it was approved by the Ethical Committee of Drum Tower Hospital affiliated with the Medical School of Nanjing University (NO.2023-158-01). Patients were divided into the normal group and coagulopathy group based on prothrombin time. The clinical characteristics of the two groups were compared using univariate analysis. The serum concentration threshold and influencing factors of cefoperazone-induced coagulopathy in critically ill patients were analyzed using the receiver operating characteristic curve and multivariate logistic regression analysis. RESULTS: A total of 113 patients were included, and cefoperazone-induced coagulopathy occurred in 39 patients, with an incidence of 34.5%. These patients experienced significant prothrombin time prolongation around day 6 (median) after cefoperazone application. The serum trough concentration threshold of cefoperazone-induced coagulopathy in critically ill patients was 87.765 mg/l. Multivariate logistic regression analysis revealed that the APACHE II score (p = 0.034), prophylactic use of vitamin K1 (p < 0.001), hepatic impairment (p = 0.014), and Cmin ≥ 87.765 mg/l (p = 0.005) were associated with cefoperazone-induced coagulopathy. CONCLUSION: Cefoperazone-induced coagulopathy usually occurs on the 6th day of cefoperazone use in critically ill patients. The risk will increase in patients with an APACHE II score > 25, hepatic impairment, and cefoperazone Cmin ≥ 87.765 mg/l. Vitamin K1 is effective in preventing this adverse reaction.


Assuntos
Transtornos da Coagulação Sanguínea , Hepatopatias , Humanos , Cefoperazona/efeitos adversos , Estudos de Casos e Controles , Estudos Retrospectivos , Estado Terminal , Fatores de Risco , Transtornos da Coagulação Sanguínea/induzido quimicamente , Vitamina K , Unidades de Terapia Intensiva
5.
Pestic Biochem Physiol ; 201: 105891, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38685253

RESUMO

The fall armyworm (Spodoptera frugiperda) was found to have invaded China in December 2018, and in just one year, crops in 26 provinces were heavily affected. Currently, the most effective method for emergency control of fulminant pests is to use of chemical pesticides. Recently, most fall armyworm populations in China were begining to exhibite low level resistance to chlorantraniliprole. At present, it is not possible to sensitively reflect the low level resistance of S. frugiperda by detecting target mutation and detoxification enzyme activity. In this study we found that 12 successive generations of screening with chlorantraniliprole caused S. frugiperda to develop low level resistance to this insecticide, and this phenotype was not attribute to genetic mutations in S. frugiperda, but rather to a marked increase in the relative amount of the symbiotic bacteria Sphingomonas. Using FISH and qPCR assays, we determined the amount of Sphingomonas in the gut of S. frugiperda and found Sphingomonas accumulation to be highest in the 3rd-instar larvae. Additionally, Sphingomonas was observed to provide a protective effect to against chlorantraniliprole stress to S. frugiperda. With the increase of the resistance to chlorantraniliprole, the abundance of bacteria also increased, we propose Sphingomonas monitoring could be adapted into an early warning index for the development of chlorantraniliprole resistance in S. frugiperda populations, such that timely measures can be taken to delay or prevent the widespread propagation of resistance to this highly useful agricultural chemical in S. frugiperda field populations.


Assuntos
Inseticidas , Larva , Sphingomonas , Spodoptera , ortoaminobenzoatos , Animais , Spodoptera/efeitos dos fármacos , Spodoptera/microbiologia , ortoaminobenzoatos/farmacologia , Inseticidas/farmacologia , Inseticidas/toxicidade , Larva/efeitos dos fármacos , Sphingomonas/efeitos dos fármacos , Sphingomonas/genética , Resistência a Inseticidas/genética
6.
Pestic Biochem Physiol ; 202: 105957, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38879339

RESUMO

Sitobion miscanthi is a destructive wheat pest responsible for significant wheat yield losses. Pirimicarb, one of the most important representatives of N, N-dimethylcarbamate insecticides, is widely used to control wheat aphids. In present work, heterozygous S431F mutation of acetylcholinesterase 1 (AChE1) was identified and verified in three pirimicarb-resistant S. miscanthi populations (two field populations (HA and HS, >955.8-fold) and one lab-selected population (PirR, 486.1-fold)), which has not been reported in S. miscanthi yet. The molecular docking results revealed that AChE1 containing the S431F mutation of S. miscanthi (SmAChE1S431F) showed higher free binding energy to three insecticides (pirimicarb, omethoate, and methomyl) than wild-type AChE1 of S. miscanthi (SmAChE1). Enzyme kinetic and inhibition experiments showed that the recombinant SmAChE1S431F was more insensitive to pirimicarb and omethoate than the recombinant SmAChE1. Furthermore, two overexpression P450 genes (CYP6K1 and CYP6A14) associated with pirimicarb resistance of S. miscanthi were verified by RNAi. These results suggested both target alteration and enhanced metabolism contributed to high pirimicarb resistance of S. miscanthi in the field and laboratory. These findings lay a foundation for further elucidating the mechanism of pirimicarb resistance in S. miscanthi, and have important implications for the resistance management of S. miscanthi control.


Assuntos
Acetilcolinesterase , Afídeos , Carbamatos , Sistema Enzimático do Citocromo P-450 , Resistência a Inseticidas , Inseticidas , Mutação , Acetilcolinesterase/genética , Acetilcolinesterase/metabolismo , Animais , Resistência a Inseticidas/genética , Afídeos/genética , Afídeos/efeitos dos fármacos , Inseticidas/farmacologia , Carbamatos/farmacologia , Sistema Enzimático do Citocromo P-450/genética , Sistema Enzimático do Citocromo P-450/metabolismo , Pirimidinas/farmacologia , Simulação de Acoplamento Molecular , Triticum/genética , Dimetoato/análogos & derivados
7.
Mikrochim Acta ; 191(6): 308, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38714541

RESUMO

A convenient self-assembly method is proposed for synthesis of 3D Au/MOF-808 (Zr) composite nanostructures with a cerium metal-organic framework loaded with gold nanoparticles. We combine adsorption properties of MOF materials with surface plasmon resonance of noble metals to construct hotspot-dense 3D Au/MOF-808 (Zr) SERS substrates, by using a two-step method of solvothermal and reduction reactions. The results show that optimal SERS substrates are obtained from a volume ratio of gold nanoparticles to MOF-808 (Zr) solution of 4:1 and a self-assembly time of 2 h. Rhodamine 6G (R6G) is used as a molecular probe to characterize and analyze SERS properties of substrates of 3D Au/MOF-808 (Zr) prepared under the optimal process conditions, where the substrates are capable to detect R6G concentrations down to 10-10 M with a relative standard deviation of 8.81%. Finally, we applied the SERS substrates of 3D Au/MOF-808 (Zr) to the detection of pesticide thiram, and establish a quantitative determination method. 3D Au/MOF-808 (Zr) provides a sensitive detection of thiram in lake water by SERS with a detection limit of 1.49 × 10-9 M. Application tests show that a SERS enhancement factor of the MOF-based SERS substrates for the detection of thiram can be significantly increased to 5.91 × 105. Thus, the above results indicate that such substrate has high sensitivity, good adsorption, homogeneity, and reproducibility, which can be extended for sensitive detection of pesticide residues in food and environment.

8.
Mikrochim Acta ; 191(3): 158, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38409501

RESUMO

An ultrasensitive surface-enhanced Raman spectroscopy (SERS) aptamer sensor (aptasensor) using a noble metal nanoparticle-magnetic nanospheres composite was developed for L-theanine detection. It makes use of Fe3O4@Au MNPs and Au@Ag NPs embedded with the Raman reporter 4-mercaptobenzoic acid (4MBA). Au@4MBA@Ag NPs modified by aptamer and Fe3O4@Au MNPs modified by cDNA created the aptasensor with the strongest Raman signal of 4MBA through the specific binding of the aptamer. With the preferred binding of L-theanine aptamer to L-theanine, Au@4MBA@Ag NPs were released from Fe3O4@Au MNPs, causing a linear decrease in SERS intensity to achieve the SERS detection of the L-theanine. The SERS peak of 4MBA at 1078 cm-1 was used for quantitative determination. SERS intensity showed a good log-linear relationship within the range 10-10 to 10-6 M of L-theanine. The aptasensor has a high selectivity for L-theanine compared with other twelve tested analytes. Hence, this aptasensor is a promising analytical tool for L-theanine detection. The developed method was applied to the analysis of real samples, demonstrating excellent performance. The comparison with the standard liquid chromatography mass spectrometry method showed an error within 20%.

9.
Zhongguo Zhong Yao Za Zhi ; 49(8): 2076-2087, 2024 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-38812224

RESUMO

Raphani Semen, with both edible and medicinal values, is a typical Chinese herbal medicine with different effects before and after processing. The raw helps ascending and the cooked helps descending. This paper comprehensively summarizes the differences in chemical constituents and pharmacological effects between raw and processed Raphani Semen that are reported in recent years. Based on the principle of quality markers(Q-markers) of traditional Chinese medicines, the chemical constituent sources, chemical constituent detection techniques, and correlation between bidirectional regulatory efficacy and chemical constituents are compared between raw and processed Raphani Semen. The results suggest that sulforaphene and glucoraphanin could be used as candidate Q-markers of raw and processed Raphani Semen, respectively. This review is expected to provide a reference for further research on the processing, new drug development, and improvement of safety and effectiveness of Raphani Semen in clinical application.


Assuntos
Medicamentos de Ervas Chinesas , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/análise , Controle de Qualidade , Humanos , Biomarcadores/análise
10.
Cogn Neurodyn ; 18(3): 1021-1032, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38826663

RESUMO

Two coordinated dynamic properties (adaptation and sensitization) are observed in retinal ganglion cells (RGCs) under the contrast stimulation. During sustained high-contrast period, adaptation decreases RGCs' responses while sensitization increases RGCs' responses. In mouse retina, adaptation and sensitization respectively show OFF- and ON-pathway-dominance. However, the mechanisms which drive the differentiation between adaptation and sensitization remain unclear. In the present study, multi-electrode recordings were conducted on isolated mouse retina under full-field contrast stimulation. Dynamic property was quantified based on the trend of RGC's firing rate during high-contrast period, light sensitivity was estimated by linear-nonlinear analysis and coding ability was estimated through stimulus reconstruction algorism. γ-Aminobutyric acid (GABA) receptors were pharmacologically blocked to explore the relation between RGCs' dynamic property and the activity of GABA receptors. It was found that GABAA and GABAC receptors respectively mediated the adaptation and sensitization processes in RGCs' responses. RGCs' dynamic property changes occurred after the blockage of GABA receptors were related to the modulation of the cells' light sensitivity. Further, the blockage of GABAA (GABAC) receptor significantly decreased RGCs' overall coding ability and eliminated the functional benefits of adaptation (sensitization). Our work suggests that the dynamic property of individual RGC is related to the balance between its GABAA-receptor-mediated inputs and GABAC-receptor-mediated inputs. Blockage of GABA receptors breaks the balance of retinal circuitry for signal processing, and down-regulates the visual information coding ability. Supplementary Information: The online version contains supplementary material available at 10.1007/s11571-023-09950-2.

11.
Int J Biol Macromol ; 260(Pt 2): 129644, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38266832

RESUMO

Afidopyropen is highly effective against sucking insects, including the Myzus persicae, that modulates the transient receptor potential vanilloid (TRPV) channel. However, the action mechanisms of afidopyropen to the TRPV channel remain unknown. In this study, the genes encoding the Nanchung (MpNan) and Inactive (MpIav) subunits of the TRPV channel of M. persicae (MpTRPV) were cloned, and their spatiotemporal expression profiles were investigated. Then, MpTRPV was functionally expressed in Xenopus laevis oocytes, and the AA residues crucial for afidopyropen binding were identified using the two-electrode voltage clamp (TEVC) technique. The results showed that both MpNan and MpIav exhibited the highest expression in the antennae and were most abundant in the 4th instar nymphs and adults. Knockdown of these two genes by RNAi greatly increased the toxicity of afidopyropen to the aphids. Moreover, the AA residues involved in afidopyropen binding to MpNan were predicted and L412 was further identified as the key residue for binding by TEVC analysis. The results also showed that afdopyropen and pymetrozine share the same binding site. These findings lay a foundation not only for exploring the mechanisms of pest target resistance to afidopyropen and pymetrozine but also for developing new insecticides targeting the TRPV channels of pests.


Assuntos
Afídeos , Compostos Heterocíclicos de 4 ou mais Anéis , Inseticidas , Lactonas , Canais de Potencial de Receptor Transitório , Animais , Afídeos/genética , Aminoácidos , Inseticidas/farmacologia
12.
Insects ; 15(2)2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38392557

RESUMO

The diamondback moth, Plutella xylostella L. (Lepidoptera: Plutellidae), is a cosmopolitan horticultural pest that is undergoing a fast, climate-driven range expansion. Its wide geographic distribution, pest status, and high incidence of insecticide resistance are directly tied to long-distance migration. Wingbeat frequency (WBF) is a key aspect of P. xylostella migratory behavior, but has received limited scientific attention. Here, we investigated the effects of environmental parameters, age, adult nutrition, and sex on P. xylostella WBF. Across experimental regimes, WBF ranged from 31.39 Hz to 78.87 Hz. Over a 10-35 °C range, the WBF of both male and female moths increased with temperature up to 62.96 Hz. Though male WBF was unaffected by humidity, females exhibited the highest WBF at 15% relative humidity (RH). WBF was unaffected by adult age, but adult nutrition exerted important impacts. Specifically, the WBF of moths fed honey water (54.66 Hz) was higher than that of water-fed individuals (49.42 Hz). Lastly, males consistently exhibited a higher WBF than females. By uncovering the biological and (nutritional) ecological determinants of diamondback moth flight, our work provides invaluable guidance to radar-based monitoring, migration forecasting, and the targeted deployment of preventative mitigation tactics.

13.
Chem Commun (Camb) ; 60(46): 5964-5967, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38767204

RESUMO

A new strategy for N-borylenamines by reaction of 2-alkynyl benzyl azides with B(C6F5)3 was developed. This novel 1,3-carboboration reaction proceeded via a 5-exo-dig cyclization/formal 1,1-carboboration/B(C6F5)2 shift reaction sequence. Additionally, N-borylenamines can undergo hetero Diels-Alder (HDA) reactions with a variety of dienophiles. Our results are an attractive complement to HDA reactions.

14.
Naunyn Schmiedebergs Arch Pharmacol ; 397(7): 4791-4798, 2024 07.
Artigo em Inglês | MEDLINE | ID: mdl-38153513

RESUMO

The primary objective of this study was to evaluate the predictors associated with target concentration (non-)attainment of imipenem in critically ill patients. The secondary objective was to explore the correlation between achieving imipenem target concentrations and clinical outcomes of therapy. A retrospective cohort study was conducted in critically ill patients treated with imipenem. Clinical data were extracted from the patients' electronic medical records. The pharmacokinetic/pharmacodynamic target was defined as free imipenem concentrations above the minimum inhibitory concentration (MIC) of the pathogen at 100% (100%fT>MIC) of the dosing interval. Factors associated with the non-attainment of target concentrations were evaluated using binomial logistic regression. Kaplan-Meier analysis was used to investigate the correlation between (non-)attainment targets and 30-day mortality. A total of 406 patients were included, and 55.4% achieved the target of 100%fT>MIC. Regression analysis identified an initial daily dose of imipenem ≤ 2 g/day, augmented renal clearance, age ≤ 60 years, recent surgery, and absence of positive microbiology culture as risk factors for target non-attainment. Achieving the 100%fT>MIC target was significantly associated with clinical efficacy but not with 30-day mortality. Selective application of therapeutic drug monitoring in the early stages of imipenem treatment for critically ill patients can improve clinical outcomes. Further research should explore the potential benefits of TDM-guided dosing strategies for imipenem in critical care settings.


Assuntos
Antibacterianos , Estado Terminal , Monitoramento de Medicamentos , Imipenem , Testes de Sensibilidade Microbiana , Humanos , Estudos Retrospectivos , Imipenem/farmacocinética , Imipenem/uso terapêutico , Imipenem/administração & dosagem , Masculino , Pessoa de Meia-Idade , Feminino , Monitoramento de Medicamentos/métodos , Antibacterianos/administração & dosagem , Antibacterianos/farmacocinética , Antibacterianos/uso terapêutico , Idoso , Resultado do Tratamento , Adulto , Estudos de Coortes
15.
Talanta ; 275: 126138, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38677164

RESUMO

Raman spectroscopy is a general and non-destructive detection technique that can obtain detailed information of the chemical structure of materials. In the past, when using chemometric algorithms to analyze the Raman spectra of mixtures, the challenges of complex spectral overlap and noise often limited the accurate identification of components. The emergence of deep learning has introduced a novel approach to qualitative analysis of mixed Raman spectra. In this paper, we propose a deep learning-based Raman spectroscopy qualitative analysis algorithm (RST) by borrowing the ideas of convolutional neural network and Transformer. By transforming the Raman spectrum into 64 word vectors, the contribution weights of each word vector to the components are obtained. For the 75 spectral data used for validation, the positive identification rate can reach 100.00 %, the recall rate can reach 99.3 %, the average identification score can reach 9.51, and it is applicable to the fields of Raman and surface-enhanced Raman spectroscopy. Furthermore, compared with traditional CNN models, RST has excellent accuracy and robustness in identifying components in complex mixtures. The model's interpretability has been enhanced, aiding in a deeper understanding of spectroscopic learning patterns for future analysis of more complex mixtures.

16.
Sci Total Environ ; 926: 171984, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38547983

RESUMO

Mesoporous silica nanoparticles (MSNs) are efficient carriers of drugs, and are promising in developing novel pesticide formulations. The cotton aphids Aphis gossypii Glover is a world devastating insect pest. It has evolved high level resistance to various insecticides thus resulted in the application of higher doses of insecticides, which raised environmental risk. In this study, the MSNs based pesticide/antibiotic delivery system was constructed for co-delivery of ampicillin (Amp) and imidacloprid (IMI). The IMI@Amp@MSNs complexes have improved toxicity against cotton aphids, and reduced acute toxicity to zebrafish. From the 16S rDNA sequencing results, Amp@MSNs, prepared by loading ampicillin to the mesoporous of MSNs, greatly disturbed the gut community of cotton aphids. Then, the relative expression of at least 25 cytochrome P450 genes of A. gossypii was significantly suppressed, including CYP6CY19 and CYP6CY22, which were found to be associated with imidacloprid resistance by RNAi. The bioassay results indicated that the synergy ratio of ampicillin to imidacloprid was 1.6, while Amp@MSNs improved the toxicity of imidacloprid by 2.4-fold. In addition, IMI@Amp@MSNs significantly improved the penetration of imidacloprid, and contributed to the amount of imidacloprid delivered to A. gossypii increased 1.4-fold. Thus, through inhibiting the relative expression of cytochrome P450 genes and improving penetration of imidacloprid, the toxicity of IMI@Amp@MSNs was 6.0-fold higher than that of imidacloprid. The greenhouse experiments further demonstrated the enhanced insecticidal activity of IMI@Amp@MSNs to A. gossypii. Meanwhile, the LC50 of IMI@Amp@MSNs to zebrafish was 3.9-fold higher than that of IMI, and the EC50 for malformation was 2.8-fold higher than IMI, respectively, which indicated that the IMI@Amp@MSNs complexes significantly reduced the environmental risk of imidacloprid. These findings encouraged the development of pesticide/antibiotic co-delivery nanoparticles, which would benefit pesticide reduction and environmental safety.


Assuntos
Afídeos , Inseticidas , Nanosferas , Animais , Inseticidas/metabolismo , Peixe-Zebra , Resistência a Inseticidas/genética , Neonicotinoides/metabolismo , Nitrocompostos/toxicidade , Nitrocompostos/metabolismo , Afídeos/metabolismo , Sistema Enzimático do Citocromo P-450/metabolismo , Ampicilina
17.
Anal Methods ; 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39140306

RESUMO

Raman spectroscopy is widely used for substance identification, providing molecular information from various components along with noise and instrument interference. Consequently, identifying components based on Raman spectra remains challenging. In this study, we collected Raman spectral data of 474 hazardous chemical substances using a portable Raman spectrometer, resulting in a dataset of 59 468 spectra. Our research employed a deep neural convolutional network based on the ResNet architecture, incorporating an attention mechanism called the SE module. By enhancing the weighting of certain spectral features, the performance of the model was significantly improved. We also investigated the classification predictive performance of the model under small-sample conditions, facilitating the addition of new hazardous chemical categories for future deployment on mobile devices. Additionally, we explored the features extracted by the convolutional neural network from Raman spectra, considering both Raman intensity and Raman shift aspects. We discovered that the neural network did not solely rely on intensity or shift for substance classification, but rather effectively combined both aspects. This research contributes to the advancement of Raman spectroscopy applications for hazardous chemical identification, particularly in scenarios with limited data availability. The findings shed light on the significance of spectral features in the model's decision-making process and have implications for broader applications of deep learning techniques in Raman spectroscopy-based substance identification.

18.
J Econ Entomol ; 2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39093635

RESUMO

Radioisotope irradiators (using cesium-137 or cobalt-60) are used as sources of ionizing radiation to control quarantine or phytosanitary insect pests in internationally traded fresh commodities and to sterilize insects used in sterile insect release programs. There are institutional initiatives to replace isotopic irradiators (producing γ-rays) with lower-energy X-ray machines due to concerns about radiological terrorism and increasingly stringent regulations on the movement of radioisotopes. Questions remain about whether the biological effects of low-energy X-rays are comparable to those of γ-rays since differences in energy levels and dose rates of X-rays may have different efficacies. We compared adult emergence, flight ability, and adult survival in the Oriental fruit fly, Bactrocera dorsalis (Hendel) (Diptera: Tephritdae), after irradiation of third instar larvae with 100 kV or 5 MeV (5,000 kV) X-rays at 20 and 40 Gy in replicated studies. At 20 Gy, the adult emergence rate was significantly lower after irradiation with 100 kV compared to 5 MeV X-rays, suggesting higher efficacy at the lower energy level. In a follow-up study using 100 kV X-rays, applying 20 Gy using a slow dose rate (0.24 Gy min-1) resulted in significantly higher adult emergence than did a fast dose rate (3.3 Gy min-1), suggesting lower efficacy. Although our study suggests higher efficacy of low energy 100 kV X-rays, there is uncertainty in measuring the dose from an X-ray tube operating at 100 kV using an ionization chamber; we discuss how this uncertainty may change the interpretation of the results. Using a 100 kV X-ray irradiator to develop a phytosanitary treatment may underestimate the dose required for insect control using commercial high-energy γ-ray or X-ray systems.

19.
Pest Manag Sci ; 80(8): 3893-3900, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38511881

RESUMO

BACKGROUND: Afidopyropen is a novel insecticide with high selectivity between sucking insects such as the peach aphids Myzus persicae and natural enemies like the seven-spotted lady beetle Coccinella septempunctata. However, the mechanisms of selective action for afidopyropen remain unknown. RESULTS: The LC50 values of afidopyropen to the 1st-4th instar larvae and adult C. septempunctata were 372- to more than 7267-fold higher than that to adult M. persicae. Though the activity of cytochrome P450s in M. persicae was 6.1- to 7.5-fold higher than that in C. septempunctata, the latter has much higher activities of carboxylesterase (CarEs) and glutathione S-transferases (GSTs), and the crude enzyme of C. septempunctata and M. persicae showed similar metabolism efficiency to afidopyropen. Molecular docking results demonstrated that afdopyropen showed higher binding affinity to the vanilloid-type transient receptor potential (TRPV) channel of M. persicae (-9.1 kcal/mol) than to that of C. septempunctata (-8.2 kcal/mol). And the EC50 value of afdopyropen to the TRPV channel of C. septempunctata (41 360 nM) was 19 885-fold higher than that in M. persicae (2.08 nM). CONCLUSIONS: Our results demonstrated that the significantly different sensitivity of M. persicae and C. septempunctata TRPV channel to afidopyropen play a key role in the high selectivity of afidopyropen. These findings provide new insights into the selective mechanisms of afidopyropen against insect pests and natural enemies as well as the theory support for coordinated application of chemical control and biological control. © 2024 Society of Chemical Industry.


Assuntos
Afídeos , Besouros , Inseticidas , Larva , Simulação de Acoplamento Molecular , Animais , Afídeos/metabolismo , Afídeos/efeitos dos fármacos , Afídeos/enzimologia , Inseticidas/farmacologia , Larva/crescimento & desenvolvimento , Proteínas de Insetos/metabolismo , Proteínas de Insetos/química , Sistema Enzimático do Citocromo P-450/metabolismo
20.
Reprod Biol ; 24(3): 100911, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38861846

RESUMO

This study aimed to investigate the pro-inflammatory and anti-inflammatory cytokines status in the peripheral blood of uRM patients. The plasma pro-inflammatory (IFN-γ, IL-6, IL-1ß, and TNF-α) and anti-inflammatory (TGF-ß1, IL-10, and IL-4) cytokines of 25 patients with uRM were compared to 33 women with a successful pregnancy. It was concluded that patients with uRM have an excess pro-inflammatory cytokines status.

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