Selection of chemical-resistant predatory mites is a good alternative to balance the contradiction between chemical control and biological control. Previously, a resistant strain of Neoseiulus barkeri for chlorpyrifos was obtained. In the current study, two up-regulated (NbCYP3A6, NbCYP3A16) and one down-regulated (NbCYP3A24) P450s were screened through differential expression analysis and other detoxification-related genes such as CCEs, GST, etc. were not found. 3D modelling and molecular docking indicated that the chlorine at position 5 on the pyridine ring of chlorpyrifos, as well as a methyl group, were closest to the heme iron of the enzymes (less than 5 Å). Three active recombinant P450 proteins were heterologously expressed and metabolized with chlorpyrifos in vitro. HPLC assay showed that only NbCYP3A24 could metabolize chlorpyrifos, with a metabolism rate of 21.60 %. Analysis of the m/z of metabolites by LC-MS/MS showed that chlorine at the 5C position of chlorpyrifos was stripped and hydroxylated, whereas chlorpyrifos-oxon, a common product of oxidation by P450, was not found. Knockdown of the NbCYP3A24 gene in the susceptiblestrain did reduce the susceptibility of N. barkeri to chlorpyrifos, suggesting that the biological activity of the metabolite may be similar to chlorpyrifos-oxon, thus enhancing the inhibitory effect on the target.

Objective: To explore the optimal regimen of standardized mite allergen immunotherapy for airway allergic diseases in children, and to observe the clinical efficacy, safety and compliance. Method: Use a retrospective real-world study, clinical data from 156 children aged 5-16 years who received subcutaneous immunotherapy (SCIT) with double mite allergen preparation in the pediatrics department of the Third Affiliated Hospital of Sun Yat sen University from June 2019 to September 2020 were selected for allergic rhinitis (AR) and/or allergic asthma (bronchial asthma, BA), including gender, age, total VAS(visual analogue scale) score and CSMS(combined symptom and medication scores) score at different time points (before treatment, 4-6 months, 1 year, and 2 years after initiation of desensitization), peripheral blood eosinophil counts (EOS), serum total IgE (tIgE), specific IgE (tIgE), and serum IgE (tIgE), specific IgE (sIgE), tIgG4, and incidence of local and systemic adverse reactions. All patients had a consistent regimen during the initial treatment phase (dose-escalation phase), which was performed as directed. Among them, 81 cases (observation group) continued to continue subcutaneous injection of 1 ml of vial No. 3 every 4-6 weeks during the dose maintenance phase, while 75 cases (control group) followed the old traditional regimen during the maintenance phase (i.e., change to a new vial to halve the amount of vial No. 3 by 0.5 ml, and then 0.75 ml after 1-2 weeks, and 1 ml in a further interval of 1-2 weeks). The clinical efficacy, safety and adherence to the treatment were compared between the two groups. Results: A total of 81 cases of 156 children were included in the observation group, of which 58 children with AR, 15 children with BA, and 8 children with AR combined with BA; 75 cases were included in the conventional control group, of which 52 children with AR, 16 children with BA, and 7 children with AR combined with BA. In terms of safety, the difference in the incidence of local and systemic adverse reactions between the two groups was not statistically significant (χ2=1.541 for local adverse reactions in the control group, χ2=0.718 for the observation group; χ2=0.483 for systemic adverse reactions in the control group, χ2=0.179 for the observation group, P value >0.05 for all of these), and there were no grade Ⅱ or higher systemic adverse reactions in any of them. In the control group, there were 15 cases of dropout at 2 years of follow-up, with a dropout rate of 20.0%; in the observation group, there were 7 cases of dropout at 2 years of follow-up, with a dropout rate of 8.6%, and there was a statistically significant difference in the dropout rates of the patients in the two groups (χ2=4.147, P<0.05). Comparison of serological indexes and efficacy (compared with baseline at 3 different time points after treatment, i.e., 4-6 months, 1 year and 2 years after treatment), CSMS scores of the observation group and the conventional control group at 4-6 months, 1 year and 2 years after treatment were significantly decreased compared with the baseline status (t-values of the conventional group were 13.783, 20.086 and 20.384, respectively, all P-values <0.001, and t-values of the observation group were 15.480, 27.087, 28.938, all P-values <0.001), and VAS scores also decreased significantly from baseline status in both groups at 4-6 months, 1 year, and 2 years of treatment (t-values of 14.008, 17.963, and 27.512 in the conventional control group, respectively, with all P-values <0.001, and t-values of 9.436, 13.184, and 22.377 in the observation group, respectively; all P-values <0.001). Intergroup comparisons showed no statistically significant differences in CSMS at baseline status, 4-6 months, 1 year and 2 years (t-values 0.621, 0.473, 1.825, and 0.342, respectively, and P-values 0.536, 0.637, 0.070, and 0.733, respectively), and VAS was no statistically significant difference in comparison between groups at different time points (t-values of 1.663, 0.095, 0.305, 0.951, P-values of 0.099, 0.925, 0.761, 0.343, respectively); suggesting that the treatment regimens of the observation group and the conventional control group were clinically effective, and that the two regimens were comparable in terms of efficacy. The peripheral blood eosinophil counts of the observation group and the conventional control group decreased significantly from the baseline status at 4-6 months, 1 year and 2 years of treatment (t-values of the conventional group were 3.453, 5.469, 6.273, P-values <0.05, and the t-values of the observation group were 2.900, 4.575, 5.988, P-values <0.05, respectively). 4-6 months, 1 year and 2 years compared with the baseline status tIgE showed a trend of increasing and then decreasing (t-value in the conventional group was -5.328, -4.254, -0.690, P-value was 0.000, 0.000, 0.492, respectively, and t-value in the observation group was -6.087, -5.087, -0.324, P-value was 0.000, 0.000, 0.745, respectively). However, the results of intergroup comparisons showed no statistically significant differences in serological indices and efficacy between the two groups in terms of peripheral blood eosinophil counts at baseline status, 4-6 months, 1 year and 2 years (t-values of 0.723, 1.553, 0.766, and 0.234, respectively; P-values of 0.471, 0.122, 0.445, and 0.815, respectively), tIgE (t-values of 0.170, -0.166, -0.449, 0.839, P-values 0.865, 0.868, 0.654, 0.403, respectively), tIgG4 (t-values 1.507, 1.467, -0.337, 0.804, P-values 0.134, 0.145, 0.737, 0.422, respectively). Conclusion: Both immunotherapy regimens for airway allergic diseases with double mite allergen subcutaneous immunotherapy have significant clinical efficacy, low incidence of adverse reactions, and the observation group has better patient compliance than the control group.
目的： 探讨儿童气道过敏性疾病标准化螨变应原免疫治疗的优化方案，观察其临床疗效、安全性和依从性。 方法： 采用回顾性真实世界研究，选取2019年6月至2020年9月在中山大学附属第三医院儿科接受双螨变应原制剂皮下免疫治疗（Subcutaneous immunotherapy，SCIT）的变应性鼻炎（allergic rhinitis，AR）和（或）过敏性哮喘（支气管哮喘，bronchial asthma，BA）的5~16岁共156例患儿的临床资料，包括性别、年龄、不同时间节点（治疗前，启动脱敏治疗后4~6个月、1年、2年时）总VAS（视觉模拟量表）评分和CSMS（综合症状和用药评分）评分、外周血中嗜酸性粒细胞计数（EOS）、血清总IgE（tIgE）、特异性IgE（sIgE）、tIgG4、局部及全身不良反应发生率。所有患者在初始治疗阶段（剂量递增阶段）的方案一致，均按说明书进行。其中，81例（观察组）在剂量维持阶段持续继续每4~6周皮下注射1次，每次注射3号瓶1 ml；75例（对照组）维持阶段按照旧的传统方案进行（即换新瓶减半量3号瓶0.5 ml，1~2周后0.75 ml，再间隔1~2周1 ml）。比较两组患者治疗的临床疗效、安全性及依从性。 结果： 156例患儿中观察组共纳入81例，其中AR患儿有58例，BA患儿15例，AR合并BA患儿有8例；常规对照组共纳入75例，AR患儿有52例，BA患儿16例，AR合并BA患儿有7例。在安全性方面，两组患者的局部和全身不良反应发生率差异均无统计学意义（局部不良反应对照组χ2=1.541，观察组χ2=0.718；全身不良反应对照组χ2=0.483，观察组χ2=0.179，P值均>0.05），且均无Ⅱ级以上全身不良反应发生。对照组随访2年脱漏15例，脱落率20.0%；观察组随访2年脱漏7例，脱落率8.6%，两组患者脱落率差异有统计学意义（χ2=4.147，P<0.05）。血清学指标及疗效对比（在治疗后3个不同的时间节点即治疗4~6个月、1年及2年时与基线进行比较），观察组和常规对照组治疗4~6个月、1年及2年时CSMS评分较基线状态明显下降（常规组t值分别为13.783，20.086，20.384，P值均<0.001；观察组t值分别为15.480，27.087，28.938，P值均<0.001）；两组患者治疗4~6个月、1年及2年时VAS评分也均较基线状态明显下降（常规组t值分别为14.008，17.963，27.512，P值均<0.001；观察组t值分别为9.436，13.184，22.377，P值均<0.001）；组间比较结果显示，基线状态、4~6个月、1年及2年时CSMS差异无统计学意义（t值分别为0.621，0.473，1.825，0.342；P值分别为0.536，0.637，0.070，0.733），VAS在不同时间点的组间比较差异也无统计学意义（t值分别为1.663，0.095，0.305，0.951；P值分别为0.099，0.925，0.761，0.343）；提示观察组和常规对照组的治疗方案均临床显效，且两种方案疗效相当。观察组和常规对照组治疗4~6个月、1年及2年时外周血嗜酸性粒细胞计数均较基线状态明显下降（常规组t值分别为3.453，5.469，6.273，P值均<0.05；观察组t值分别为2.900，4.575，5.988，P值均<0.05），两组患者在治疗4~6个月、1年及2年时较基线状态tIgE呈现先升高后降低的趋势（常规组t值分别为-5.328，-4.254，-0.690，P值分别为0.000，0.000，0.492；观察组t值分别为-6.087，-5.087，-0.324，P值分别为0.000，0.000，0.745）。但组间比较结果显示血清学指标及疗效在基线状态、4~6个月、1年及2年时外周血嗜酸性粒细胞计数在两组之间无明显统计学差异（t值分别为0.723，1.553，0.766，0.234；P值分别为0.471，0.122，0.445，0.815），tIgE（t值分别为0.170，-0.166，-0.449，0.839；P值分别为0.865，0.868，0.654，0.403），tIgG4（t值分别为1.507，1.467，-0.337，0.804；P值分别为0.134，0.145，0.737，0.422）。 结论： 针对气道过敏性疾病双螨变应原皮下免疫治疗的两种免疫治疗方案均有显著的临床疗效，不良反应发生率低，观察组较对照组患者依从性更好。.

Megalurothrips usitatus (Bagnall) (Thysanoptera: Thripidae) is an important pest in Vigna unguiculata (L.) Walp. Neoseiulus barkeri (Hughes) (Acari: Phytoseiidae) is widely used for control of pest mites and insects worldwide. We evaluated its effect on M. usitatus when predators (N. barkeri) or insecticides (Spinetoram) were applied in the fields. Neoseiulus barkeri Hughes consumed 80% of M. usitatus prey offered within 6 h, and predation showed Type III functional response with prey density. The maximum consumption of N. barkeri was 27.29 ± 1.02 individuals per d per arena (1.5 cm diameter), while the optimal prey density for the predatory mite was 10.35 ± 0.68 individuals per d per arena (1.5 cm diameter). The developmental duration of N. barkeri fed with M. usitatus was significantly shorter than those fed with the dried fruit mite, Carpoglyphus lactis (L.) (Acari: Astigmata). In field trials, the efficiency of N. barkeri against M. usitatus was not significantly different from that of applications of the insecticide spinetoram. Biodiversity of other insects in treated fields was assessed, and there were 21 insect species in garden plots treated with N. barkeri releases. The total abundance (N), Shannon\'s diversity index (H), Pielou\'s evenness index (J) and Simpson\'s diversity index (D) of the garden plots treated with predatory mites were all significantly higher than that in the garden plots treated with spinetoram, where we found no species of predators or parasitoids and 7 herbivores. Our results show that N. barkeri is a potential means to control M. usitatus while preserving arthropod diversity at the level of treated gardens.

Dermanyssus gallinae, a worldwide pest in birds, has developed varying degrees of resistance to insecticides. The ATP-binding cassette (ABC) transporters are essential for the removal of xenobiotics from arthropods. However, our knowledge about ABC transporter proteins in D. gallinae is limited. Forty ABC transporters were identified in the transcriptome and genome of D. gallinae. The resistant population displayed an augmented metabolic rate for beta-cypermethrin compared to the susceptible group, with a remarkable increase in the content of ABC transporters. Verapamil was found able to increase the toxicity of beta-cypermethrin in the resistant population. Results from qRT-PCR analysis showed that eleven ABC transcripts were more highly expressed in the resistant population than the susceptible group at all stages of development, and beta-cypermethrin was observed to be able to induce the expression of DgABCA5, DgABCB4, DgABCD3, DgABCE1 and DgABCG5 in D. gallinae. RNAi-mediated knockdown of the five genes was observed to increase the susceptibility of resistant mites to beta-cypermethrin. These results suggest that ABC transporters, DgABCA5, DgABCB4, DgABCD3, DgABCE1 and DgABCG5 genes, may be related to beta-cypermethrin resistance in D. gallinae. This research will serve as a foundation for further studies on mechanism of insecticide resistance, which could be beneficial for controlling D. gallinae.

The long-term use of pesticides in the field, and the high fertility and adaptability of phytophagous mites have led to resistance problems; consequently, novel safe and efficient active substances are necessary to broaden the tools of pest mite control. Natural enemies of arthropods typically secrete substances with paralytic or lethal effects on their prey, and those substances are a resource for future biopesticides. In this study, two putative venom peptide genes were identified in a parasitic mite Neoseiulus barkeri transcriptome. Recombinant venom NbSP2 peptide injected into Tetranychus cinnabarinus mites was significantly more lethal than recombinant NBSP1. NbSP2 was also lethal to Spodoptera litura when injected but not when fed to third instar larvae. The interaction proteins of NbSP2 in T. cinnabarinus and S. litura were identified by affinity chromatography. Among these proteins, ATP synthase subunit β (ATP SSβ) was deduced as a potential target. Four binding sites were predicted between NBSP2 and ATP SSβ of T. cinnabarinus and S. litura. In conclusion, we identified a venom peptide with activity against T. cinnabarinus and S. litura. This study provides a novel component for development of a new biological pesticide.

Indoor cases of Tetranychus cinnabarinus displaying resistance have been documented, but the resistance level in field populations remains unexplored in China. This study delves into the resistance dynamics of T. cinnabarinus to fenpropathrin in various field populations across China, a pressing concern in contemporary agricultural pest control. The conventional bioassay and amplicon sequencing reveal a notable absence of significant fenpropathrin resistance in field populations, contrasting with known resistance in indoor cases. Current study highlights the limitations of traditional bioassays in detecting early-stage resistance and underscores the nuanced capabilities and constraints of amplicon sequencing in resistance gene frequency analysis. By employing an integrated approach, we combined dose-response bioassays, amplicon sequencing, and statistical modeling to assess resistance levels and investigate underlying genetic factors. The model with empirical data indicates that a 5% mutation frequency represents the threshold before resistance emerges. However, the detection of the kdr mutation in certain populations ranging from 0 to 1.2%, signals an early looming threat of future resistance emergence. Additionally, we further assessed a specific dsRNA targeting VGSC genes at two concentrations (10 ng/μL and 100 ng/μL), both inducing substantial mortality by silencing target genes effectively. The exploration of RNA interference (RNAi) as a novel, more environmentally friendly pest control measure opens new avenues, despite the ongoing challenge of resistance evolution. Overall, this study underscores the necessity for evolving pest management strategies, integrating advanced biotechnological approaches with traditional methods, to effectively counter pesticide resistance and ensure sustainable agricultural productivity.

The goji berry psyllid, Bactericera gobica Logniova (Homoptera: Psyllidae), is one of the most important pests on goji berry plants (Lycium barbarum L.), whose fruits are widely used in traditional Chinese medicine and food. However, chemical control is still the predominant control strategy of this pest. Recently, two species of predatory mites, Neoseiulus setarius Ma, Meng & Fan and Neoseiulus barkeri Hughes were found to be associated with B. gobica in China. To assess their predation potential against B. gobica, the functional responses of these two phytoseiid species feeding on different densities (2, 4, 8, 12, 16, 24 and 32 individuals) of B. gobica eggs and 1st instar nymphs were compared at a temperature of 25ºC ± 1º C. Logistic regression analysis revealed that both predatory mite species exhibited type Holling-II functional responses on eggs and 1st instar nymphs of B. gobica, with the predation number increased for both predators as the density of prey increased. Overall, N. setarius consumed more prey compared to N. barkeri across all levels of prey densities. Meanwhile, the highest attack rate (α = 0.0283), the lowest handling time (Th = 1.1324 h prey- 1), and the highest estimated maximum predation rate (T/Th = 21.19 prey day- 1) were all observed for N. setarius fed with 1st instar nymphs of B. gobica. These findings suggest that it is worthy considering utilizing N. setarius and N. barkeri as candidate biocontrol agents of B. gobica, with N. setarius appearing to be a more effective predator than N. barkeri.

OBJECTIVE: To investigate the bacterial community diversity in human Demodex mites, so as to provide insights into unraveling the role of human Demodex mites in them caused infectious diseases.
METHODS: From June to July 2023, Demodex mites were collected from the faces of college students in a university in Wuhu City using the adhesive tape method, and the V4 region of 16S ribosomal RNA (16S rRNA) gene and the internal transcribed spacer (ITS) gene of nuclear ribosomal DNA were amplified on an Illumina PE250 high-throughput sequencing platform. Sequencing data were spliced according to the overlapping relations and filtered to yield effective sequences, and operational taxonomic units (OTUs) was clustered. The diversity index of obtained OUTs was analyzed, and the structure of the bacterial community was analyzed at various taxonomic levels.
RESULTS: A total of 57 483 valid sequences were obtained using 16S rRNA gene sequencing, and 159 OUTs were classified according to similarity. Then, OUTs at a 97% similarity were included for taxonomic analyses, and the bacteria in Demodex mites belonged to 14 phyla, 20 classes, 51 orders, 72 families, and 94 genera. Proteobacteria was the dominant phylum, and Vibrio, Bradyrhizobium and Variovorax were dominant genera. A total of 56 362 valid sequences were obtained using ITS gene sequencing, and 147 OTUs were obtained, which belonged to 5 phyla, 17 classes, 34 orders, 68 families, and 93 genera and were annotated to Ascomycota, Basidiomycota and Chytridiomycota, with Ascomycota as the dominant phylum, and Alternaria alternata, Epicoccum, Penicillium, and Sarocladium as dominant genera.
CONCLUSIONS: There is a high diversity in the composition of bacterial communities in human Demodex mites, with multiple types of microorganisms and high species abundance.
［摘要］ 目的 分析人体蠕形螨体内细菌群落多样性, 为探究蠕形螨在其所致传染病中的作用提供参考依据。方法 2023 年 6—7 月通过透明胶纸法采集芜湖市某高校大学生面部蠕形螨, 通过 Illumina PE250 高通量测序平台扩增 16S 核糖体 RNA (16S ribosomal RNA, 16S rRNA) 基因 V4 区以及核糖体 DNA 内转录间隔区 (internal transcribed spacer, ITS) 基 因, 将测序结果根据重叠关系进行拼接、过滤得到有效序列, 再进行操作分离单元 (operational taxonomic units, OTU) 聚 类。对得到的 OTU 进行多样性指数分析, 并在不同分类水平对细菌菌落结构进行统计分析。结果 16S rRNA 测序获得 57 483 条有效序列, 根据不同相似度水平对其进行 OTU 分类, 得到 159 个 OTUs; 对其中 97% 相似水平的 OTU 进行分类学 水平分析, 发现人体蠕形螨体内细菌分属于 14 个门、20 个纲、51 个目、72个科、94 个属。在门分类水平, 变形菌门为优势 菌门; 在属分类水平上, 弧菌属、慢生根瘤菌和贪噬菌属为优势菌属。ITS 测序共获得 56 362 条有效序列及 147 个 OTUs, 分属于 5 个门、17 个纲、34 个目、68 个科、93 个属; 注释到子囊菌门、担子菌门、壶菌属门和毛囊菌门等, 子囊菌门为优势 菌门, 链格孢菌属、附球菌属、青霉菌属和帚枝霉属为优势菌属。结论 蠕形螨体内细菌群落组成具有较高多样性, 同时 微生物种类较多、物种丰度较高。.

BACKGROUND: Plants have numerous defensive secondary metabolites to withstand insect attacks. Scoparone, which is extracted from the medicinal plant Artemisia capillaris, has potent acaricidal effects on Tetranychus cinnabarinus. Spirodiclofen, derived from a tetronic acid derivative, is a potent commercial acaricide that is extensively used globally. However, whether scoparone has synergistic effects when used in conjunction with spirodiclofen and the underlying synergistic mechanism remains unclear.
RESULTS: Scoparone exhibited a potent synergistic effect when it was combined with spirodiclofen at a 1:9 ratio. Subsequently, cytochrome P450 monooxygenase (P450) activity, RNA-Seq and qPCR assays indicated that the enzyme activity of P450 and the expression of one P450 gene from T. cinnabarinus, TcCYP388A1, were significantly inhibited by scoparone and spirodiclofen + scoparone; conversely, P450 was activated in spirodiclofen-exposed mites. Importantly, RNAi-mediated silencing of the TcCYP388A1 gene markedly increased the susceptibility of spider mites to spirodiclofen, scoparone and spirodiclofen + scoparone, and in vitro, the recombinant TcCYP388A1 protein could metabolize spirodiclofen. Molecular docking and functional analyses further indicated that R117, which is highly conserved in Arachnoidea species, may be a vital specific binding site for scoparone in the mite TcCYP388A1 protein. This binding site was subsequently confirmed using mutagenesis data, which revealed that this binding site was the sole site selected by scoparone in spider mites over mammalian or fly CYP388A1.
CONCLUSIONS: These results indicate that the synergistic effects of scoparone and spirodiclofen on mites occurs through the inhibition of P450 activity, thus reducing spirodiclofen metabolism. The synergistic effect of this potent natural product on the detoxification enzyme-targeted activity of commercial acaricides may offer a sustainable strategy for pest mite resistance management. © 2024 Society of Chemical Industry.

BACKGROUND: The biological control agent Phytoseiulus persimilis is a commercialized specialist predator of two agricultural pest mite species Tetranychus urticae and Tetranychus evansi. Biocontrol of these pest species by P. persimilis has achieved success in biological control in some areas. However, the lack of precise information about the influence of global climate change on the worldwide distribution of this biocontrol agent hampers international efforts to manage pest mites with P. persimilis. With 276 occurrence records and 19 bioclimatic variables, this study investigated the potential global distribution of P. persimilis.
RESULTS: The results demonstrated that the Maximum Entropy (MaxEnt) model performed well, with the area under the curve being 0.956, indicating the high accuracy of this model. Two variables, the minimum temperature of the coldest month (Bio_6) and precipitation of the coldest quarter (Bio_19) were the most important environmental variables that influenced the distribution of P. persimilis, contributing more than 30% to the model, respectively. The suitable area currently occupies 21.67% of the world\'s land area, spanning latitudes between 60°S and 60°N. Under shared socio-economic pathway (SSP) 5-8.5 (high-carbon emissions), the low suitable area would increase by 1.31% until the 2050s.
CONCLUSIONS: This study successfully identified that south-eastern China, parts of countries in the Mediterranean coastal regions, including Libya, Algeria, Portugal, Spain, and France, are climatically favorable regions for P. persimilis, providing valuable information about the potential areas where it can be effectively exploited as biocontrol agents in classical biological control programs to manage pest spider mites environmentally friendly. © 2024 Society of Chemical Industry.