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2.
Environ Res ; : 110716, 2021 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-33421429

RESUMO

The complex and changeable environment is a brand-new living condition for the viruses and pathogens released by the infected people to the indoor air or deposited on the surface of objects, which is an important external condition affecting the decay and transmission risk of the viruses. Exposure to contaminated surfaces is one of the main routes of respiratory diseases transmission. Therefore, it is very important for epidemic prevention and control to study the law of virus decay and the environmental coupling effect on various surfaces. Based on the analysis of the influencing mechanism, a large amount of experimental evidence on the survival of viruses on the surface of objects were excavated in this paper, and the effects of various factors, such as surface peripheral temperature, relative humidity, virus-containing droplet volume, surface materials and virus types, on the decay rate constants of viruses were comprehensively analyzed. It was found that although the experimental methods, virus types and experimental conditions varied widely in different experiments, the virus concentrations on the surface of objects all followed the exponential decay law, and the coupling effect of various factors was reflected in the decay rate constant k. Under different experimental conditions, k values ranged from 0.001 to 100 h-1, with a difference of 5 orders of magnitude, corresponding to the characteristic time t99 between 500 to 0.1 hour when the virus concentration decreased by 99%. This indicates a large variation in the risk of virus transmission in different scenarios. By revealing the common law and individuality of the virus decay on the surface of objects, the essential relationship between the experimental observation phenomenon and virus decay was analyzed. This paper points out the huge difference in virus transmission risk on the surface at different time nodes, and discusses the prevention and control strategies to grasp the main contradictions in the different situations.

3.
Semin Cancer Biol ; 2021 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-33421619

RESUMO

Drug resistance, either intrinsic or acquired, represents a major hurdle to achieving optimal therapeutic outcomes during cancer treatment. In addition to acquisition of resistance-conferring genetic mutations, accumulating evidence suggests an intimate involvement of the epigenetic machinery in this process as well. Recent studies have revealed that epigenetic reprogramming, such as altered expression or relocation of DNA/histone modulators accompanied with chromatin structure remodeling, can lead to transcriptional plasticity in tumor cells, thereby driving their transformation towards a persistent state. These "persisters" represent a pool of slow-growing cells that can either re-expand when treatment is discontinued or acquire permanent resistance. Targeting epigenetic reprogramming or plasticity represents a new strategy to prevent the emergence of drug-refractory populations and to enable more consistent clinical responses. With the growing numbers of drugs or drug candidates developed to target epigenetic regulators, more and more epigenetic therapies are under preclinical evaluation, early clinical trials or approved by FDA as single agent or in combination with existing antitumor drugs. In this review, we highlight latest discoveries in the mechanistic understanding of epigenetically-induced drug resistance. In parallel, we discuss the potential of combining epigenetic drugs with existing anticancer regimens as a promising strategy for overcoming cancer drug resistance.

5.
Talanta ; 224: 121852, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33379068

RESUMO

Reduced glutathione (GSH) and the oxidized glutathione (GSSG) are well-known biomolecules in the main constituents of intracellular redox homeostasis system. A rapid, accurate measurement of cellular GSH and GSSG is quite needed in investigating important biochemical events. In this work, we present a novel and sensitive method to monitor intracellular GSH and GSSG concentrations by a portable surface-enhanced Raman spectroscopy (SERS) technique. We introduced a reduction-sensitive reaction-type Raman probe, 5,5'-dithiobis-(2-nitrobenzoic acid) (DTNB) to initiate GSH reduction, itself concomitantly converts to 2-nitro-5-thiobenzoic acid (TNB) to release a strong SERS signal. In a convenient way of inorganic salt MgSO4 induced aggregation of silver nanoparticles substrate, we easily implemented a good discrimination between DTNB and TNB, and a quantitative measurement of GSH and GSSG with a high sensitivity of 10 nM. This SERS method proved its feasible applicability in rapidly and sensitively monitoring GSH depletion behaviors of some notorious alkylating agents, i.e., sulfur mustard and nitrogen mustards in ex vitro or in vitro (cellular response). This SERS method may be very worthwhile in cellular detoxication event via the GSH approach and other GSH involved biomedical researches.

6.
J Proteome Res ; 20(1): 346-356, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33241931

RESUMO

Identification of phosphorylation sites is an important step in the function study and drug design of proteins. In recent years, there have been increasing applications of the computational method in the identification of phosphorylation sites because of its low cost and high speed. Most of the currently available methods focus on using local information around potential phosphorylation sites for prediction and do not take the global information of the protein sequence into consideration. Here, we demonstrated that the global information of protein sequences may be also critical for phosphorylation site prediction. In this paper, a new deep neural network model, called DeepPSP, was proposed for the prediction of protein phosphorylation sites. In the DeepPSP model, two parallel modules were introduced to extract both local and global features from protein sequences. Two squeeze-and-excitation blocks and one bidirectional long short-term memory block were introduced into each module to capture effective representations of the sequences. Comparative studies were carried out to evaluate the performance of DeepPSP, and four other prediction methods using public data sets The F1-score, area under receiver operating characteristic curves (AUROC), and area under precision-recall curves (AUPRC) of DeepPSP were found to be 0.4819, 0.82, and 0.50, respectively, for S/T general site prediction and 0.4206, 0.73, and 0.39, respectively, for Y general site prediction. Compared with the MusiteDeep method, the F1-score, AUROC, and AUPRC of DeepPSP were found to increase by 8.6, 2.5, and 8.7%, respectively, for S/T general site prediction and by 20.6, 5.8, and 18.2%, respectively, for Y general site prediction. Among the tested methods, the developed DeepPSP method was also found to produce best results for different kinase-specific site predictions including CDK, mitogen-activated protein kinase, CAMK, AGC, and CMGC. Taken together, the developed DeepPSP method may offer a more accurate phosphorylation site prediction by including global information. It may serve as an alternative model with better performance and interpretability for protein phosphorylation site prediction.

7.
Esophagus ; 18(1): 125-137, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32474721

RESUMO

BACKGROUND: Esophageal squamous cell carcinoma (ESCC) and leiomyoma are common tumors. The coexistence of these two tumors can be classified into two types: the overlying type and the separate type. The overlying type is rare. METHODS: We report 12 cases of the overlying type treated by endoscopic submucosal dissection (ESD). They underwent pre-ESD endoscopic examination with white-light imaging, iodine staining, narrow-band imaging, endoscopic ultrasound, and biopsy. The clinical, endoscopic and pathologic characteristics were reviewed. RESULTS: Among the 12 patients, 3 were female and 9 were male. The age range was 49-76 years. They accounted for 4.0% of 300 cases of esophageal leiomyoma and 1.3% of 955 cases of superficial ESCC or high-grade dysplasia treated by endoscopic resection. After endoscopic examination and biopsy, ESCC or high-grade dysplasia, combined with leiomyoma was considered in four cases; leiomyoma was considered but without the squamous lesion (underdiagnosis) in another case; and leiomyoma was mistaken for submucosal ESCC (overdiagnosis) in the other seven cases. ESD specimens showed that nine cases were intramucosal or submucosal ESCC, and three cases were high-grade dysplasia, overlying leiomyoma originating from the muscularis mucosae or muscularis propria. The 12 cases were successfully treated by ESD, with no recurrence during follow-up. CONCLUSIONS: We must keep in mind that ESCC or high-grade dysplasia can occur overlying leiomyoma. These cases are rare but should not be neglected, especially in high-risk areas for ESCC. These patients can receive appropriate treatment if overdiagnosis or underdiagnosis can be avoided.

8.
Toxicol Sci ; 179(1): 31-43, 2021 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-33078836

RESUMO

Drug-induced liver injury (DILI) is a leading cause of acute liver failure. Reliable and translational biomarkers are needed for early detection of DILI. microRNAs (miRNAs) have received wide attention as a novel class of potential DILI biomarkers. However, it is unclear how DILI drugs other than acetaminophen may influence miRNA expression or which miRNAs could serve as useful biomarkers in humans. We selected ketoconazole (KCZ), a classic hepatotoxin, to study miRNA biomarkers for DILI as a proof of concept for a workflow that integrated in vivo, in vitro, and bioinformatics analyses. We examined hepatic miRNA expression in KCZ-treated rats at multiple doses and durations using miRNA-sequencing and correlated our results with conventional DILI biomarkers such as liver histology. Significant dysregulation of rno-miR-34a-5p, rno-miR-331-3p, rno-miR-15b-3p, and rno-miR-676 was associated with cytoplasmic vacuolization, a phenotype in rat livers with KCZ-induced injury, which preceded the elevation of serum liver transaminases (ALT and AST). Between rats and humans, miR-34a-5p, miR-331-3p, and miR-15b-3p were evolutionarily conserved with identical sequences, whereas miR-676 showed 73% sequence similarity. Using quantitative PCR, we found that the levels of hsa-miR-34a-5p, hsa-miR-331-3p, and hsa-miR-15b-3p were significantly elevated in the culture media of HepaRG cells treated with 100 µM KCZ (a concentration that induced cytotoxicity). Additionally, we computationally characterized the miRNA candidates for their gene targeting, target functions, and miRNA/target evolutionary conservation. In conclusion, we identified miR-34a-5p, miR-331-3p, and miR-15b-3p as translational biomarker candidates for early detection of KCZ-induced liver injury with a workflow applicable to computational toxicology studies.

9.
Waste Manag ; 119: 22-29, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33039978

RESUMO

Supergravity technology is an efficient method for the separation of trace elements from Al-Mg alloys made of their scraps. This study investigated the enrichment and separation behavior of impurities from Al-Mg alloy using supergravity technology under various conditions. After supergravity enrichment, nonmetallic inclusions and precipitated intermetallic compounds were concentrated at the bottom of the samples, and the enrichment degree positively correlated with the gravity coefficient. High-purity Al-Mg alloys was obtained with efficient impurity removal from the alloy melt of the scraps by filtration in supergravity fields. Improving the gravity coefficient benefited the recoveries of the Al and Mg but had little influence on the purity of the obtained Al-Mg alloy. Although the recoveries of the Al and Mg increased slightly with increasing the separation temperature, the removal rates of the metallic impurities were relatively low at elevated temperatures. At the temperature of 500 °C, gravity coefficient of 600, and separation time of 1 min, 91.6% and 90.1% of Al and Mg were recovered, respectively. Their corresponding mass fractions in the filtered Al-Mg alloy were 99.2 wt%. An amplified experimental centrifugal separation apparatus was also designed for purifying the alloys on an engineering scale. The results indicate that supergravity technology is feasible on an industrial scale and that it can be potentially employed as a separation and purification process.


Assuntos
Ligas , Tecnologia , Temperatura
10.
IEEE Trans Biomed Eng ; 68(1): 192-203, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32746031

RESUMO

Magnetic resonance electrical properties tomography (MR-EPT) maps the spatial distribution of the patient's electrical conductivity and permittivity using the measured B1 data in a magnetic resonance imaging (MRI) system. Existing MR-EPT methods are usually not clinically accessible owing to their technical limits such as strong noise sensitivity. In this study, we develop a new MR-EPT method that re-expresses the involved differential equations (DEs) based on the divergence theorem. In comparison with traditional methods, the proposed method avoids the grid-wise computation of the second-order derivatives of B1+ , thereby improving the robustness against noise. Besides, for applications where the structural information can be determined in advance, EPs of a region of interest (ROI) can be calculated in a fast and efficient manner. The proposed method is firstly validated with numerical simulations, in which a three-block phantom and an anatomically accurate Duke Head model are used to evaluate the proposed method. Experiments on the 9.4T MRI system were then conducted to validate the simulations. Both results indicated that the proposed MR-EPT solution could provide a more robust reconstruction of electrical properties maps compared with conventional methods.

11.
J Med Chem ; 63(24): 15852-15863, 2020 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-33291877

RESUMO

To validate the hypothesis that Tyr748 is a crucial residue to aid the discovery of highly selective phosphodiesterase 8A (PDE8A) inhibitors, we identified a series of 2-chloroadenine derivatives based on the hit clofarabine. Structure-based design targeting Tyr748 in PDE8 resulted in the lead compound 3a (IC50 = 0.010 µM) with high selectivity with a reasonable druglike profile. In the X-ray crystal structure, 3a bound to PDE8A with a different mode from 3-isobutyl-1-methylxanthine (a pan-PDE inhibitor) and gave a H-bond of 2.7 Å with Tyr748, which possibly interprets the 220-fold selectivity of 3a against PDE2A. Additionally, oral administration of compound 3a achieved remarkable therapeutic effects against vascular dementia (VaD), indicating that PDE8 inhibitors could serve as potential anti-VaD agents.

12.
Chem Biol Interact ; 334: 109353, 2020 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-33309543

RESUMO

Perhexiline is a coronary vasodilator for angina treatment that was first developed in the 1960s. Perhexiline enjoyed worldwide success before reports of severe side effects, such as hepatotoxicity and neurotoxicity, caused its withdrawal from most of the markets. The underlying mechanism of the cytotoxicity of perhexiline, however, is not yet well understood. Here we demonstrated that perhexiline induced cellular damage in primary human hepatocytes, HepaRG cells and HepG2 cells. Analysis of gene and protein expression levels of endoplasmic reticulum (ER) stress markers showed that perhexiline caused ER stress in primary human hepatocytes and HepG2 cells. The splicing of XBP1 mRNA, a hallmark of ER stress, was observed upon perhexiline treatment. Using Gluc-Fluc-HepG2 cell line, we demonstrated that protein secretion was impaired upon perhexiline treatment, suggesting functional deficits in ER. Inhibition of ER stress using ER inhibitor 4-PBA or salubrinal attenuated the cytotoxicity of perhexiline. Directly knocking down ATF4 using siRNA also partially rescued HepG2 cells upon perhexiline exposure. In addition, inhibition of ER stress using either inhibitors or siRNA transfection attenuated perhexiline-induced increase in caspase 3/7 activity, indicating that ER stress contributed to perhexiline-induced apoptosis. Moreover, perhexiline treatment resulted in activation of p38 and JNK signaling pathways, two branches of MAPK cascade. Pre-treating HepG2 cells with p38 inhibitor SB239063 attenuated perhexiline-induced apoptosis and cell death. The inhibitor also prevented the activation of CHOP and ATF4. Overall, our study demonstrated that ER stress is one important mechanism underlying the hepatotoxicity of perhexiline, and p38 signaling pathway contributes to this process. Our finding shed light on the role of both ER stress and p38 signaling pathway in drug-induced liver injury.

13.
Curr Opin Plant Biol ; 59: 101970, 2020 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-33296747

RESUMO

Stolons and rhizomes are modified stems for vegetative reproduction. While stolons grow above the ground, rhizomes grow beneath the ground. Stolons and rhizomes maintain the genotypes of hybrids and hence are invaluable for agricultural propagation. Diploid strawberry is a model for studying stolon development. At the axillary meristems, gibberellins and MADS box gene SOC1 promote stolon formation, while the DELLA repressor inhibits stolon development. Photoperiod regulates stolon formation through regulating GA biosynthesis or balancing asexual with sexual mode of reproduction in the axillary meristems. In rhizomatous wild rice, the BLADE-ON-PETIOLE gene promotes sheath-to-blade ratio to confer rhizome tip stiffness and support underground growth. Together, this review aims to encourage further investigations into stolon and rhizome to benefit agriculture and environment.

14.
Int J Eat Disord ; 2020 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-33350490

RESUMO

In the past 40 years, the prevalence of eating disorders (ED) in China has shown an increasing trend, leading to an urgent need to develop efficient treatment modes and methods. Since the beginning of the new century, the diagnosis, treatment, and research of ED in China have been under development. This article gives an introduction and commentary on the treatment modes, treatment methods and their applications in ED in China. There are two main treatment forms for ED until now, that is, inpatient treatment and outpatient treatment. Inpatient treatment is recommended as the first choice. Since 2008, clinical psychotherapies such as cognitive behavioral therapy (CBT), dialectical behavioral therapy (DBT), and family-based treatment (FBT), which are effective for pathological symptoms of ED, have been introduced into China and developed clinically. Group CBT and group DBT for patients with ED and group FBT for caregivers might be the most efficient psychotherapy in China nowadays. A multi-family FBT support group could be developed as the basic treatment of ED patients. Although these new types of psychotherapy have observed effectiveness in clinical application, the Randomized Controlled Trials (RCT) are rare and need to be developed.

15.
Front Cardiovasc Med ; 7: 550428, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33304926

RESUMO

Background: The number of coronary chronic total occlusion (CTO) patients with renal insufficiency is huge, and limited data are available on the impact of renal insufficiency on long-term clinical outcomes in CTO patients. We aimed to investigate clinical outcomes of CTO percutaneous coronary intervention (PCI) vs. medical therapy (MT) in CTO patients according to baseline renal function. Methods: In the study population of 2,497, 1,220 patients underwent CTO PCI and 1,277 patients received MT. Patients were divided into four groups based on renal function: group 1 [estimated glomerular filtration rate (eGFR) ≥ 90 ml/min/1.73 m2], group 2 (60 ≤ eGFR <90 ml/min/1.73 m2), group 3 (30 ≤ eGFR <60 ml/min/1.73 m2), and group 4 (eGFR <30 ml/min/1.73 m2). Major adverse cardiac event (MACE) was the primary end point. Results: Median follow-up was 2.6 years. With the decline in renal function, MACE (p < 0.001) and cardiac death (p < 0.001) were increased. In group 1 and group 2, MACE occurred less frequently in patients with CTO PCI, as compared to patients in the MT group (15.6% vs. 22.8%, p < 0.001; 15.6% vs. 26.5%, p < 0.001; respectively). However, there was no significant difference in terms of MACE between CTO PCI and MT in group 3 (21.1% vs. 28.7%, p = 0.211) and group 4 (28.6% vs. 50.0%, p = 0.289). MACE was significantly reduced for patients who received successful CTO PCI compared to patients with MT (16.7% vs. 22.8%, p = 0.006; 16.3% vs. 26.5%, p = 0.003, respectively) in group 1 and group 2. eGFR < 30 ml/min/1.73 m2, age, male gender, diabetes mellitus, heart failure, multivessel disease, and MT were identified as independent predictors for MACE in patients with CTOs. Conclusions: Renal impairment is associated with MACE in patients with CTOs. For treatment of CTO, compared with MT alone, CTO PCI may reduce the risk of MACE in patients without chronic kidney disease (CKD). However, reduced MACE from CTO PCI among patients with CKD was not observed. Similar beneficial effects were observed in patients without CKD who underwent successful CTO procedures.

16.
PLoS One ; 15(12): e0244683, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33382788

RESUMO

With the continuous improvement of automation and informatization, the electromagnetic environment has become increasingly complex. Traditional protection methods for electronic systems are facing with serious challenges. Biological nervous system has the self-adaptive advantages under the regulation of the nervous system. It is necessary to explore a new thought on electromagnetic protection by drawing from the self-adaptive advantage of the biological nervous system. In this study, the scale-free spiking neural network (SFSNN) is constructed, in which the Izhikevich neuron model is employed as a node, and the synaptic plasticity model including excitatory and inhibitory synapses is employed as an edge. Under white Gaussian noise, the noise suppression abilities of the SFSNNs with the high average clustering coefficient (ACC) and the SFSNNs with the low ACC are studied comparatively. The noise suppression mechanism of the SFSNN is explored. The experiment results demonstrate that the following. (1) The SFSNN has a certain degree of noise suppression ability, and the SFSNNs with the high ACC have higher noise suppression performance than the SFSNNs with the low ACC. (2) The neural information processing of the SFSNN is the linkage effect of dynamic changes in neuron firing, synaptic weight and topological characteristics. (3) The synaptic plasticity is the intrinsic factor of the noise suppression ability of the SFSNN.

17.
Am J Cancer Res ; 10(11): 3705-3720, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33294262

RESUMO

GOLM1, a type II transmembrane protein, is associated with tumor progression, metastasis and immunosuppression. However, the relationship between GOLM1 and the immunosuppressive molecule PD-L1 in HCC remains largely unclear. Here, we revealed that GOLM1 acts as a novel positive regulator of PD-L1, whose abnormal expression plays a crucial role in cancer immune evasion and progression. We found that GOLM1 is overexpressed and positively correlated with PD-L1 expression in HCC. Mechanistically, we found that GOLM1 promotes the phosphorylation of STAT3 by enhancing the level of EGFR, which in turn upregulates the transcriptional expression of PD-L1. Taken together, we demonstrated that GOLM1 acts as a positive regulator of PD-L1 expression via the EGFR/STAT3 signaling pathway in human HCC cells. This study provides a new insight into the regulatory mechanism of PD-L1 expression in HCC, which may provide a novel therapeutic target for HCC immunotherapy.

18.
J Clin Neurosci ; 82(Pt A): 13-19, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33317721

RESUMO

The study aimed to investigate the role of serum homocysteine in hemorrhagic transformation (HT) and symptomatic intracranial hemorrhage (sICH) within 24 h of intravenous (IV) recombinanttissueplasminogenactivator(rt-PA) in acute ischemic stroke (AIS) patients. 236 consecutive AIS patients (169 men, median 65 years old) who underwent to IV rt-PA within 4.5 h of symptom onset were retrospectively recruited and analyzed. The serum homocysteine levels ranged from 4.45 to 67.71 (median 12.05) µmol/L. HT was observed in 28 (11.9%) patients, including 7 (3.0%) sICH patients within 24 h of IV rt-PA. Multiple parameters were compared between HT and non-HT patients as well as sICH and non-sICH patients. The serum homocysteine levels were higher in patients with HT than in those without HT (13.00 vs. 11.70 µmol/L, P = 0.025) and an independent association between serum homocysteine level and HT within 24 h of IV rt-PA was identified via multivariable logistic regression analysis (odds ratio [OR] = 1.103, 95% confidence interval [CI] = 1.021-1.191, P = 0.013). Moreover, serum homocysteine levels were also significantly higher in patients with sICH than in those without sICH (15.19 vs. 11.73 µmol/L, P = 0.005).Our study suggests that serum homocysteine level is an independent predictor for HT within 24 h of IV rt-PA in AIS patients.

19.
IEEE Trans Cybern ; PP2020 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-33284759

RESUMO

This article is concerned with a quasiperiodic disturbance estimation problem for dynamic control systems without prior knowledge on frequency. As a major challenge of our work, the quasiperiodic disturbance to be treated is always submerged by untargeted waves, leading to complicated coupling between disturbance separation and frequency identification. Existing approaches on quasiperiodic disturbance rejection have circumvented, rather than overcome, this challenge by assuming either a known frequency or a measurable disturbance signal. In this work, an expectation-maximization (EM) framework is proposed where disturbance signal separation and frequency identification are carried out in an iterative manner. In the E-step, the expected log-likelihood function is evaluated via reconstruction of the quasiperiodic signal based on the latest frequency estimate; and in the M-step, the frequency estimate is updated by maximizing the log-likelihood function obtained in the E-step. To facilitate recursive frequency estimation, an online EM algorithm is also developed based on the forward-only smoothing techniques. Furthermore, we show that the proposed method can be easily extended to deal with nonlinear system models and time-varying frequencies.

20.
Insect Sci ; 2020 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-33200870

RESUMO

Cyantraniliprole is the first diamide insecticide to have cross-spectrum activity against a broad range of insect orders. The insecticide, like other diamides, selectively acts on ryanodine receptor, destroys Ca2+ homeostasis, and ultimately causes insect death. Although expression regulations of genes associated with calcium signaling pathways are known to be involved in the response to diamides, little is known regarding the function of calmodulin (CaM), a typical Ca2+ sensor central in regulating Ca2+ homeostasis, in the stress response of insects to the insecticide. In this study, we cloned and identified the full-length complementary DNA of CaM in the whitefly, Bemisia tabaci (Gennadius), named BtCaM. Quantitative real-time reverse transcription polymerase chain reaction-based analyses showed that the messenger RNA level of BtCaM was rapidly induced from 1.51- to 2.43-fold by cyantraniliprole during 24 h. Knockdown of BtCaM by RNA interference increased the toxicity of cyantraniliprole in whiteflies by 42.85%. In contrast, BtCaM expression in Sf9 cells significantly increased the cells' tolerance to cyantraniliprole as much as 2.91-fold. In addition, the expression of BtCaM in Sf9 cells suppressed the rapid increase of intracellular Ca2+ after exposure to cyantraniliprole, and the maximum amplitude in the Sf9-BtCaM cells was only 34.9% of that in control cells (Sf9-PIZ/V5). These results demonstrate that overexpression of BtCaM is involved in the stress response of B. tabaci to cyantraniliprole through regulation of Ca2+ concentration. As CaM is one of the most evolutionarily conserved Ca2+ sensors in insects, outcomes of this study may provide the first details of a universal insect response to diamide insecticides.

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