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MicroRNA (miRNA) is crucial to the diagnose of various diseases. However, the accurate detection of miRNA has been challenging due to its short length and low abundance. Here, we designed a hybridization chain reaction (HCR) circuit controller to initiate the CRISPR/Cas12a conversion amplifier (HCR-Cas12a controller) for sensitive detection of miRNA-21 (miR-21). In the HCR, pre-crRNA was encapsulated in a hairpin structure until the miR-21 was present. Afterward, Cas12a fully exerted its RNase activity to self-mature pre-crRNA. Then, the trans-cleavage activity of Cas12a was initiated by activator. This results in the conversion of biological signals to fluorescent signal. During HCR-Cas12a controller, the circuit formed quickly, while the Cas12a system worked in a short time. The miR-21 was ultra-sensitively detected with the wide detection range of 1 fM - 100 nM, and the calculated limit of detection was 75.4 aM. The sensitivity was an order of magnitude lower than the standard method. The formation of HCR at room temperature does not require a thermal cycler. Additionally, Cas12a can work without the need for precise or expensive instruments. Therefore, our proposed method was suitable for low-resource settings, and provided a technical basis for sensitive detection of miRNA in low concentration range.
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Sistemas CRISPR-Cas , MicroRNAs , Hibridização de Ácido Nucleico , Corantes , MicroRNAs/genética , RNA Guia de Sistemas CRISPR-CasRESUMO
Obstructive sleep apnea (OSA) is a severe sleep disorder associated with intermittent hypoxia and sleep fragmentation. Cognitive impairment is a signifi- cant and common OSA complication often described in such patients. The most commonly utilized methods in clinical OSA treatment are oral appliances and continuous positive airway pressure (CPAP). However, the current therapeutic methods for improving cognitive function could not achieve the expected efficacy in same patients. Therefore, further understanding the molecular mechanism behind cognitive dysfunction in OSA disease will provide new treatment methods and targets. This review briefly summarized the clinical manifestations of cognitive impairment in OSA disease. Moreover, the pathophysiological molecular mechanism of OSA was outlined. Our study concluded that both SF and IH could induce cognitive impairment by multiple signaling pathways, such as oxidative stress activation, inflammation, and apoptosis. However, there is a lack of effective drug therapy for cognitive impairment in OSA. Finally, the therapeutic potential of some novel compounds and herbal medicine was evaluated on attenuating cognitive impairment based on certain preclinical studies.
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Leaf rust, caused by Puccinia hordei, is one of the most widespread and damaging foliar diseases affecting barley. The barley leaf rust resistance locus Rph7 has been shown to have unusually high sequence and haplotype divergence. In this study, we isolate the Rph7 gene using a fine mapping and RNA-Seq approach that is confirmed by mutational analysis and transgenic complementation. Rph7 is a pathogen-induced, non-canonical resistance gene encoding a protein that is distinct from other known plant disease resistance proteins in the Triticeae. Structural analysis using an AlphaFold2 protein model suggests that Rph7 encodes a putative NAC transcription factor with a zinc-finger BED domain with structural similarity to the N-terminal DNA-binding domain of the NAC transcription factor (ANAC019) from Arabidopsis. A global gene expression analysis suggests Rph7 mediates the activation and strength of the basal defence response. The isolation of Rph7 highlights the diversification of resistance mechanisms available for engineering disease control in crops.
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Arabidopsis , Basidiomycota , Eczema , Hordeum , Fatores de Transcrição/genética , Hordeum/genética , Regulação da Expressão Gênica , Poaceae , Arabidopsis/genética , Proteínas de Plantas/genética , Doenças das Plantas/genéticaRESUMO
Catalytic methods which control multiple stereogenic centers simultaneously are highly desirable in modern organic synthesis and chemical manufacturing. Herein, we report a regio-, enantio-, and diastereoselective NiH-catalyzed hydroalkylation process which proceeds with simultaneous control of vicinal stereocenters originating from two readily accessible partners, prochiral internal alkenes (enamides or enecarbamates) and racemic alkyl electrophiles (α-bromoamides or Katritzky salts). This reaction produces high-value ß-aminoamides and their derivatives under mild conditions and with precise selectivity. Preliminary studies of the mechanism indicate that the reaction involves an enantioselective syn-hydronickelation to generate an enantiomerically enriched alkylnickel(II) species. Subsequent enantioconvergent alkylation with a racemic alkyl electrophile generates the desired product as a single stereoisomer.
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A promising and sustainable approach for producing hydrogen peroxide is the two-electron oxygen reduction reaction (2e- ORR), which uses very stable graphitic carbon nitride (g-C3N4). However, the catalytic performance of pristine g-C3N4 is still far from satisfactory. Here, we demonstrate for the first time the controlled fabrication of carbon quantum dots (CQDs)-modified graphitic carbon nitride carbon (g-C3N4/CQDs-X) by ultrasonic stripping for efficient 2e- ORR electrocatalysis. HRTEM, UV-vis, EPR and EIS analyses are in good consistent which prove the in-situ generation of CQDs. The effect of sonication time on the physical properties and ORR activity of g-C3N4 is discussed for the first time. The g-C3N4/CQDs-12 catalyst shows a selectivity of up to 95% at a potential of 0.35 V vs. RHE, which is much higher than that of the original g-C3N4 catalyst (88%). Additionally, the H2O2 yield is up to 1466.6 mmol g-1 in 12 h, which is twice as high as the original g-C3N4 catalyst. It is discovered that the addition of CQDs through ultrasonic improves the g-C3N4 catalyst's electrical conductivity and electron transfer capability in addition to its high specific surface area and distinctive porous structure, speeding up the reaction rate. This research offers a green method for enhancing g-C3N4 activity.
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Biliary obstruction diseases are often complicated by an impaired intestinal barrier, which aggravates liver injury. Treatment of the intestinal barrier is often neglected. To investigate the mechanism by which intestinal bile acid deficiency mediates intestinal barrier dysfunction after biliary obstruction and identify a potential therapeutic modality, we mainly used a bile duct ligation (BDL) mouse model to simulate biliary obstruction and determine the important role of the bile acid receptor FXR in maintaining intestinal barrier function and stemness. Through RNA-seq analysis of BDL and sham mouse crypts and qRT-PCR performed on intestinal epithelial-specific Fxr knockout (FxrΔIEC) and wild-type mouse crypts, we found that FXR might maintain intestinal stemness by regulating CYP11A1 expression. Given the key role of CYP11A1 during glucocorticoid production, we also found that FXR activation could promote intestinal corticosterone (CORT) synthesis by ELISA. Intestinal organoid culture showed that an FXR agonist or corticosterone increased crypt formation and organoid growth. Further animal experiments showed that corticosterone gavage treatment could maintain intestinal barrier function and stemness, decrease LPS translocation, and attenuate liver injury in BDL mice. Our study hopefully provides a new theoretical basis for the prevention of intestinal complications and alleviation of liver injury after biliary obstruction.
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Colestase , Corticosterona , Animais , Camundongos , Ácidos e Sais Biliares , Enzima de Clivagem da Cadeia Lateral do Colesterol , IntestinosRESUMO
The varying antioxidant potential of Citrus medica associated with different geographical regions makes the evaluation of C. medica for natural antioxidants essential. This work aimed to compare the antioxidant potential of the phenolic constituents from different geographical regions. The chemical compositions were characterized by ultra-high-performance liquid chromatography (UPLC) coupled with mass spectrometry (MS). A total of 67 compounds including 29 coumarin derivatives and 38 flavonoids were tentatively identified by UPLC-quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS). To evaluate the quality of C. medica from seven different geographical regions, water and 80% methanol fractions were subjected to quantitative analysis. Antioxidant potentials were determined by 2,2-diphenyl-1-picrylhydrazyl, 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), iron chelation, and reduction methods. The samples collected from Sichuan province showed the highest content of total phenolic compounds. Combined with antioxidant results, the sample from Sichuan province presented good antioxidant activity. This study also showed that total phenolic compounds significantly contributed to the antioxidant activities (2,2-azinobis(3-ethyl-benzothiazoline-6-sulphonic acid) and radical scavenging activity) of C. medica samples (p < 0.01). These results provided chemical information and potential antioxidant value for further research, providing ideal evidence for the quality evaluation and exploitation of the source.
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Owing to the feature of strong α-glucosidase inhibitory activity, 1-deoxynojirimycin (1-DNJ) has broad application prospects in areas of functional food, biomedicine, etc., and this research wants to construct an efficient strain for 1-DNJ production, basing on Bacillus amyloliquefaciens HZ-12. Firstly, using the temperature-sensitive shuttle plasmid T2 (2)-Ori, gene ptsG in phosphotransferase system (PTS) was weakened by homologous recombination, and non-PTS pathway was strengthened by deleting its repressor gene iolR, and 1-DNJ yield of resultant strain HZ-S2 was increased by 4.27-fold, reached 110.72 mg/L. Then, to increase precursor fructose-6-phosphate (F-6-P) supply, phosphofructokinase was weaken, fructose phosphatase GlpX and 6-phosphate glucose isomerase Pgi were strengthened by promoter replacement, moreover, regulator gene nanR was deleted, 1-DNJ yield was further increased to 267.37 mg/L by 2.41-fold. Subsequently, promoter of 1-DNJ synthetase cluster was optimized, as well as 5'-UTRs of downstream genes in synthetase cluster, and 1-DNJ produced by the final strain reached 478.62 mg/L. Last but not the least, 1-DNJ yield of 1632.50 mg/L was attained in 3 L fermenter, which was the highest yield of 1-DNJ reported to date. Taken together, our results demonstrated that metabolic engineering was an effective strategy for 1-DNJ synthesis, this research laid a foundation for industrialization of functional food and drugs based on 1-DNJ.
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L-Sorbosone dehydrogenase (SNDH) is a key enzyme involved in the biosynthesis of 2-keto-L-gulonic acid , which is a direct precursor for the industrial scale production of vitamin C. Elucidating the structure and the catalytic mechanism is essential for improving SNDH performance. By solving the crystal structures of SNDH from Gluconobacter oxydans WSH-004, a reversible disulfide bond between Cys295 and the catalytic Cys296 residues is discovered. It allowed SNDH to switch between oxidation and reduction states, resulting in opening or closing the substrate pocket. Moreover, the Cys296 is found to affect the NADP+ binding pose with SNDH. Combining the in vitro biochemical and site-directed mutagenesis studies, the redox-based dynamic regulation and the catalytic mechanisms of SNDH are proposed. Moreover, the mutants with enhanced activity are obtained by extending substrate channels. This study not only elucidates the physiological control mechanism of the dehydrogenase, but also provides a theoretical basis for engineering similar enzymes.
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S-adenosyl-L-methionine (SAM), a sulfonium-based cofactor, plays an important role in numerous biological processes as methyl donor. Inspired by the function of sulfonium motif in this nature's synthetic toolkit, we here present an aryne-activation strategy that the sulfonium intermediates in situ generated from thioethers display unique reactivity toward alkyl group transposition. Experimental and theoretical studies indicate that the reaction occurs in an intermolecular fashion where the TfO--incorporated [K(18-crown-6)] complex acts as a key promoter for this thermodynamically favored process. Next, a series of robust, easy-to-prepare sulfonium salts are designed and developed as electrophilic alkylation reagents accordingly. Both systems feature for broad scope, excellent selectivity, and simple operation. Moreover, we highlight the synthetic value through molecular editing and late-stage modification of complex scaffolds or even active pharmaceutical ingredients.
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The tripartite motif proteins (TRIMs) family represents a class of highly conservative proteins which play a large regulatory role in molecular processes. Recently, increasing evidence has demonstrated a role of TRIMs in female genital neoplasms. Our review thereby aimed to provide an overview of the biological involvement of TRIMs in female genital neoplasms, to provide a better understanding of its role in the development and progression of such diseases, and emphasize its potential as targeted cancer therapy. Overall, our review highlighted that the wide-ranging roles of TRIMs, in not only target protein ubiquitination, tumor migration and/or invasion, epithelial-mesenchymal transition, stemness, cell adhesion, proliferation, cell cycle regulation, and apoptosis, but also in influencing estrogenic, and chemotherapy response.
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This paper developed an electrical micro flow cytometry to realize leukocyte differentials leveraging a constrictional microchannel and a deep neural network. Firstly, purified granulocytes, lymphocytes or monocytes traveled through the constrictional microchannel with a cross-sectional area marginally larger than individual cells and produced large impedance variations by blocking focused electric field lines. By optimizing key elements (e.g., normalization, learning rate, batch size and neuron number) of the recurrent neural network (RNN), electrical results of purified leukocytes were analyzed to establish a leukocyte differential system with a classification accuracy of 95.2%. Then the leukocyte mixtures were forced to travel through the same constrictional microchannel, producing mixed impedance profiles which were classified into granulocytes, lymphocytes and monocytes based on the aforementioned differential system. As to the classification results, two leukocyte mixtures from the same donor were processed, producing comparable classification results, which were 57% versus 59% of granulocytes, 37% versus 34% of lymphocytes and 6% versus 7% of monocytes. These results validated the established classification system based on the constrictional microchannel and the recurrent neural network, providing a new perspective of differentiating white blood cells by electrical flow cytometry.
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Recent advancements in next-generation sequencing (NGS) technology and bioinformatics tools have revealed a vast array of viral diversity in insects, particularly RNA viruses. However, our current understanding of insect RNA viruses has primarily focused on hematophagous insects due to their medical importance, while research on the viromes of agriculturally relevant insects remains limited. This comprehensive review aims to address the gap by providing an overview of the diversity of RNA viruses in agricultural pests and beneficial insects within the agricultural ecosystem. Based on the NCBI Virus Database, over eight hundred RNA viruses belonging to 39 viral families have been reported in more than three hundred agricultural insect species. These viruses are predominantly found in the insect orders of Hymenoptera, Hemiptera, Thysanoptera, Lepidoptera, Diptera, Coleoptera, and Orthoptera. These findings have significantly enriched our understanding of RNA viral diversity in agricultural insects. While further virome investigations are necessary to expand our knowledge to more insect species, it is crucial to explore the biological roles of these identified RNA viruses within insects in future studies. This review also highlights the limitations and challenges for the effective virus discovery through NGS and their potential solutions, which might facilitate for the development of innovative bioinformatic tools in the future.
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Type 2 diabetes mellitus (T2DM) has been the most prevalent disease and has become a serious public health threat worldwide. Gynura bicolor (Willd.) DC. (GB) contains a variety of nutrients and possesses numerous activities, which might benefit those with diabetes. The current study aimed to confirm the improvement of metabolic disorders and explore the potential mechanism of GB in high fat diet-fed (HFD) and streptozotocin (STZ)-induced T2DM mice. The aboveground sample of GB was extracted with alcohol, and identified by highperformance liquid chromatography (HPLC) and liquid chromatography-Mass Spectrometry/Mass Spectrometry (LC-MS/MS) analysis. HFD and STZ-induced T2DM mice were administrated with GB extract. Biochemical and histopathologic examinations were conducted, and metabolomics evaluation was performed in serum and urine. GB significantly reduced body weight and liver weight, reversed hyperlipidemia, hyperglycemia, insulin resistance, oxidative stress and inflammation, improved hepatic histopathological changes and lipid deposition and mitigated liver injury in T2DM mice. Serum and urine metabolomics demonstrated a variety of significantly disturbed metabolites in T2DM and these changes were reversed after GB administration, including 13S-hydroxyoctadecadienoic acid, arachidonic acid, L-Valine and so on. According to the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis, the overlapping enriched pathways in the normal control group and GB group were identified, including linoleic acid metabolism, PPAR signaling pathway, protein digestion and absorption, biosynthesis of amino acids and so on. This study demonstrates that the ethanol extract of GB remarkably attenuates metabolic disorders and maintains the dynamic balance of metabolites in T2DM, providing a scientific basis for GB in the treatment of T2DM and metabolism diseases.
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PURPOSE: This study investigated the protective effect of probucol on Müller cells exposed to high glucose conditions and examined potential mechanisms of action. METHODS: Primary human retinal Müller cells were incubated with high glucose (HG, 35 mM) in the present or absence of different concentrations of probucol for 24 h. Cell viability was determined using the CCK-8 method. Mitochondrial membrane potential (MMP) was measured using JC-1 staining and cell cycle by flow cytometry. The expression of nuclear factor E2-related factor 2 (Nrf2), glutamate-cysteine ligase catalytic subunit, and p62 was quantified using quantitative polymerase chain reaction and western blot. RESULTS: We found that HG inhibited cell proliferation, arrested cell cycle, and increased MMP in human Müller cells. Probucol activated the Nrf2/p62 pathway and upregulated the anti-apoptotic protein, Bcl2, and attenuated HG-mediated damage in Müller cells. CONCLUSIONS: Our results suggest that probucol may protect Müller cells from HG-induced damage through enhancing the Nrf2/p62 signaling pathway.
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Achieving perfect absorption in few-layer two-dimensional (2D) materials plays a crucial role in applications such as optoelectronics and sensing. However, the underlying mechanisms of all reported works imply a strongly inherent dependence of the central wavelength on the structural parameters. Here, we propose a structure-parameter-deviation immune method for achieving perfect absorption at any desired wavelength by harnessing the toroidal dipole-bound state in the continuum (TD BIC). We experimentally demonstrate the versatile design with a monolayer-graphene-loaded compound grating structure. Such a TD BIC built upon the TE31 mode allows for the transition from BIC to quasi-BIC without breaking the structural symmetry, enabling the stable resonance wavelength while tailoring the quality factors via variation of the gap distance. Comparison with traditional literature further reveals the superiority of our method in realizing highly robust perfect absorption, with a wavelength stability ratio of >15. Remarkably, this approach can be straightforwardly applied to other 2D materials.
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BACKGROUND: Saccharomyces cerevisiae has been used in the biosynthesis of acid products such as organic acids owing to its acid tolerance. Improving the acid tolerance of S. cerevisiae is beneficial for expanding its application range. Our previous study isolated the TAMC strain that was tolerant to a pH 2.3 through adaptive laboratory evolution; however, its mechanism underlying tolerance to low pH environment remains unclear. RESULTS: In this study, through visual observation and order analysis of plasma membrane and membrane microdomains, we revealed that the membrane microdomains of TAMC strain play an indispensable role in acid tolerance. Transcriptomic analysis showed an increase in the expression of genes related to key components of membrane microdomains in TAMC strain. Furthermore, an obvious reduction was observed in the acid tolerance of the strain with sterol C-24 methyltransferase encoding gene ERG6 knockout for inhibiting membrane microdomain formation. Finally, colocalization analysis of H+-ATPase PMA1 and plasma membrane protein PMP1 showed that disruption of membrane microdomains could inhibit the formation of the H+-ATPase complex. CONCLUSIONS: Membrane microdomains could provide a platform for forming H+-ATPase complexes to facilitate intracellular H+ homeostasis, and thereby improve cell acid resistance. This study proposed a novel acid tolerance mechanism, providing a new direction for the rational engineering of acid-tolerant strains.
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Perfilação da Expressão Gênica , Saccharomyces cerevisiae , Saccharomyces cerevisiae/genética , Membrana Celular , Técnicas de Inativação de Genes , Microdomínios da MembranaRESUMO
BACKGROUND: There are many risk factors for severe acute pancreatitis (SAP) complicated with acute gastrointestinal injury (AGI), but few reports on the interaction between these risk factors. AIM: To analyze the risk factors for SAP complicated with AGI and their interactive effects. METHODS: We selected 168 SAP patients admitted to our hospital between December 2019 and June 2022. They were divided into AGI group and non-AGI group according to whether AGI was present. Demographic data and laboratory test data were compared between the two groups. The risk factors for SAP with concomitant AGI were analyzed using multifactorial logistic regression, and an analysis of the interaction of the risk factors was performed. RESULTS: The percentage of patients with multiple organ dysfunction syndrome, acute physiological and chronic health scoring system II (APACHE II) score, white blood cell count and creatinine (CRE) level was higher in the AGI group than in the non-AGI group. There was a statistically significant difference between the two groups (P < 0.05). Logistic regression analysis indicated that an APACHE II score > 15 and CRE > 100 µmol/L were risk factors for SAP complicating AGI. The interaction index of APACHE II score and CRE level was 3.123. CONCLUSION: An APACHE II score > 15 and CRE level > 100 µmol/L are independent risk factors for SAP complicated with AGI, and there is a positive interaction between them.
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Garnet-type Li6.4La3Zr1.4Ta0.6O12 (LLZTO) is a highly promising solid-state lithium metal battery electrolyte due to its exceptional ionic conductivity and electrochemical stability. However, when exposed to air, a passivation layer can be spontaneously formed on the garnet-type electrolyte, deteriorating its wettability with metallic lithium (Li) and impeding the lithium ion transfer at the Li-garnet electrolyte interface. The passivation layer is considered a critical issue for garnet-type solid electrolytes. Despite intensive research, the formation mechanism of the passivation film remains poorly understood. The key to elucidating the formation mechanism is to obtain a pristine garnet electrolyte surface and study how the pristine garnet electrolyte interacts with air. In this study, different passivation layer removal pretreatments were performed to expose pristine garnet electrolytes, and their impacts on the samples were systematically studied. The results reveal the overlooked negative impacts of vacuum annealing and acid treatment on LLZTO, which are indicated by the severe loss of Li and O and the formation of additional Li-depleted metal oxides. It was confirmed that argon annealing is the only viable approach to remove the passivation layer without introducing concomitant contaminations to LLZTO. Based on this method, we directly evidenced the formation of LiOH on LLZTO under rarefied air using quasi-in situ X-ray photoelectron spectroscopy. It was confirmed that the loss of Li and O ions, rather than Li+/H+ exchange, drives the formation of LiOH in the passivation layer. These results not only provide a better understanding of the surface and interface chemistry of LLZTO but also reveal a reliable surface treatment for the LLZTO sample.
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Controlled pesticide delivery systems offer many distinctive advantages over conventional pesticide formulations. In this work, degradable poly(N-isopropylacrylamide) (PNIPAM)-tannic acid (TA) microgels and multifunctional PDA@PNIPAM-TA nanocomposites were prepared in a high-gravity rotating packed bed reactor (RPB) for smart pesticide delivery and release. The as-prepared microgels and nanocomposites showed reversible temperature-dependent swelling/deswelling behavior and irreversible pH-induced degradation. A dynamic contact angle test suggested that the introduction of TA and PDA into the PNIPAM matrix could enhance foliar adhesion and deposition efficiency. The nanocomposites were further used for the encapsulation and delivery of imidacloprid (IMI) to protect it from rapid photolysis and improve its pest-control efficiency. Their thermoresponsive behavior as well as pesticide loading capacity could be tuned by tailoring the PNIPAM-TA shell thickness, which could be varied by the NIPAM amount. The release rate of IMI from the core/shell nanocomposites was positively correlated with environmental temperature and near-infrared (NIR) light, which was adaptive to the positive temperature-dependent toxicity correlation of IMI and the increasing trend of pests under high temperature. The cumulative release of IMI was 23.5% at 25 °C, while it was 81.2% at 40 °C after 24 h of incubation, and the release rate was greatly enhanced under NIR irradiation. The results indicated that the facile control of pesticide release could be realized by regulating environmental conditions. This work also provides an idea for using high-gravity technology to conveniently construct a smart, effective, and environmentally friendly pesticide delivery system for sustainable crop protection.