Fusion dsRNA designs incorporating multiple target sequences can enhance the aphid control capacity of an RNAi-based strategy

BACKGROUND

RNA interference (RNAi) is the sequence-dependent suppression of gene expression by double-stranded RNA (dsRNA). This is a promising strategy for the control of insect pests because dsRNA can be rationally designed to maximize efficacy and biosafety, the latter by using sequences that are found in target pests but are safe for non-target insects. However, this has yet to be optimized in aphids, destructive sap-sucking pests that also transmit plant viruses. We used the green peach aphid (Myzus persicae) as a case study to optimize the efficiency of RNAi by applying a novel fusion dsRNA design.

RESULTS

Comparative transcriptomics revealed a number of genes that are induced in feeding aphids, and eight candidate genes were chosen as RNAi targets. To improve RNAi efficiency, our fusion dsRNA design approach combined optimal gene fragments (highly conserved in several aphid species but with less homology in beneficial insects such as the predator ladybeetle Propylea japonica) from three candidate genes. We compared this RNAi-based biological control approach with conventional chemical control using imidacloprid. We found that the fusion dsRNA strategy inhibited the aphid population to a significantly greater extent than single-target RNAi and did not affect ladybeetle fitness, allowing an additive effect between RNAi and natural predation, whereas imidacloprid was harmful to aphids and ladybeetles.

CONCLUSION

Our fusion dsRNA design approach enhances the ability of RNAi to control aphids without harming natural predators. © 2024 Society of Chemical Industry.

RNA interference in insects: the link between antiviral defense and pest control

RNA interference (RNAi) is a form of gene silencing triggered by double-stranded RNA (dsRNA) that operates in all eukaryotic cells. RNAi has been widely investigated in insects to determine the underlying molecular mechanism, to investigate its role in systemic antiviral defense, and to develop strategies for pest control. When insect cells are infected by viruses, viral dsRNA signatures trigger a local RNAi response to block viral replication and generate virus-derived DNA that confers systemic immunity. RNAi-based insect pest control involves the application of exogenous dsRNA targeting genes essential for insect development or survival, but the efficacy of this approach has limited potency in many pests through a combination of rapid dsRNA degradation, inefficient dsRNA uptake/processing, and ineffective RNAi machinery. This could be addressed by dsRNA screening and evaluation, focusing on dsRNA design and off-target management, as well as dsRNA production and delivery. This review summarizes recent progress to determine the role of RNAi in antiviral defense and as a pest control strategy in insects, addressing gaps between our fundamental understanding of the RNAi mechanism and the exploitation of RNAi-based pest control strategies.

Insect-specific RNA virus affects the stylet penetration activity of brown citrus aphid (Aphis citricidus) to facilitate its transmission

Sap-sucking insects often transmit plant viruses but also carry insect viruses, which infect insects but not plants. The impact of such insect viruses on insect host biology and ecology is largely unknown. Here, we identified a novel insect-specific virus carried by brown citrus aphid (Aphis citricidus), which we tentatively named Aphis citricidus picornavirus (AcPV). Phylogenetic analysis discovered a monophyletic cluster with AcPV and other unassigned viruses, suggesting that these viruses represent a new family in order Picornavirales. Systemic infection with AcPV triggered aphid antiviral immunity mediated by RNA interference, resulting in asymptomatic tolerance. Importantly, we found that AcPV was transmitted horizontally by secretion of the salivary gland into the feeding sites of plants. AcPV influenced aphid stylet behavior during feeding and increased the time required for intercellular penetration, thus promoting its transmission among aphids with plants as an intermediate site. The gene expression results suggested that this mechanism was linked with transcription of salivary protein genes and plant defense hormone signaling. Together, our results show that the horizontal transmission of AcPV in brown citrus aphids evolved in a manner similar to that of the circulative transmission of plant viruses by insect vectors, thus providing a new ecological perspective on the activity of insect-specific viruses found in aphids and improving the understanding of insect virus ecology.

Effects of empagliflozin on progression of chronic kidney disease: a prespecified secondary analysis from the empa-kidney trial

BACKGROUND

Sodium-glucose co-transporter-2 (SGLT2) inhibitors reduce progression of chronic kidney disease and the risk of cardiovascular morbidity and mortality in a wide range of patients. However, their effects on kidney disease progression in some patients with chronic kidney disease are unclear because few clinical kidney outcomes occurred among such patients in the completed trials. In particular, some guidelines stratify their level of recommendation about who should be treated with SGLT2 inhibitors based on diabetes status and albuminuria. We aimed to assess the effects of empagliflozin on progression of chronic kidney disease both overall and among specific types of participants in the EMPA-KIDNEY trial.

METHODS

EMPA-KIDNEY, a randomised, controlled, phase 3 trial, was conducted at 241 centres in eight countries (Canada, China, Germany, Italy, Japan, Malaysia, the UK, and the USA), and included individuals aged 18 years or older with an estimated glomerular filtration rate (eGFR) of 20 to less than 45 mL/min per 1·73 m2, or with an eGFR of 45 to less than 90 mL/min per 1·73 m2 with a urinary albumin-to-creatinine ratio (uACR) of 200 mg/g or higher. We explored the effects of 10 mg oral empagliflozin once daily versus placebo on the annualised rate of change in estimated glomerular filtration rate (eGFR slope), a tertiary outcome. We studied the acute slope (from randomisation to 2 months) and chronic slope (from 2 months onwards) separately, using shared parameter models to estimate the latter. Analyses were done in all randomly assigned participants by intention to treat. EMPA-KIDNEY is registered at ClinicalTrials.gov, NCT03594110.

FINDINGS

Between May 15, 2019, and April 16, 2021, 6609 participants were randomly assigned and then followed up for a median of 2·0 years (IQR 1·5-2·4). Prespecified subgroups of eGFR included 2282 (34·5%) participants with an eGFR of less than 30 mL/min per 1·73 m2, 2928 (44·3%) with an eGFR of 30 to less than 45 mL/min per 1·73 m2, and 1399 (21·2%) with an eGFR 45 mL/min per 1·73 m2 or higher. Prespecified subgroups of uACR included 1328 (20·1%) with a uACR of less than 30 mg/g, 1864 (28·2%) with a uACR of 30 to 300 mg/g, and 3417 (51·7%) with a uACR of more than 300 mg/g. Overall, allocation to empagliflozin caused an acute 2·12 mL/min per 1·73 m2 (95% CI 1·83-2·41) reduction in eGFR, equivalent to a 6% (5-6) dip in the first 2 months. After this, it halved the chronic slope from -2·75 to -1·37 mL/min per 1·73 m2 per year (relative difference 50%, 95% CI 42-58). The absolute and relative benefits of empagliflozin on the magnitude of the chronic slope varied significantly depending on diabetes status and baseline levels of eGFR and uACR. In particular, the absolute difference in chronic slopes was lower in patients with lower baseline uACR, but because this group progressed more slowly than those with higher uACR, this translated to a larger relative difference in chronic slopes in this group (86% [36-136] reduction in the chronic slope among those with baseline uACR <30 mg/g compared with a 29% [19-38] reduction for those with baseline uACR ≥2000 mg/g; ptrend<0·0001).

INTERPRETATION

Empagliflozin slowed the rate of progression of chronic kidney disease among all types of participant in the EMPA-KIDNEY trial, including those with little albuminuria. Albuminuria alone should not be used to determine whether to treat with an SGLT2 inhibitor.

FUNDING

Boehringer Ingelheim and Eli Lilly.

Impact of primary kidney disease on the effects of empagliflozin in patients with chronic kidney disease: secondary analyses of the EMPA-KIDNEY trial

BACKGROUND

The EMPA-KIDNEY trial showed that empagliflozin reduced the risk of the primary composite outcome of kidney disease progression or cardiovascular death in patients with chronic kidney disease mainly through slowing progression. We aimed to assess how effects of empagliflozin might differ by primary kidney disease across its broad population.

METHODS

EMPA-KIDNEY, a randomised, controlled, phase 3 trial, was conducted at 241 centres in eight countries (Canada, China, Germany, Italy, Japan, Malaysia, the UK, and the USA). Patients were eligible if their estimated glomerular filtration rate (eGFR) was 20 to less than 45 mL/min per 1·73 m2, or 45 to less than 90 mL/min per 1·73 m2 with a urinary albumin-to-creatinine ratio (uACR) of 200 mg/g or higher at screening. They were randomly assigned (1:1) to 10 mg oral empagliflozin once daily or matching placebo. Effects on kidney disease progression (defined as a sustained ≥40% eGFR decline from randomisation, end-stage kidney disease, a sustained eGFR below 10 mL/min per 1·73 m2, or death from kidney failure) were assessed using prespecified Cox models, and eGFR slope analyses used shared parameter models. Subgroup comparisons were performed by including relevant interaction terms in models. EMPA-KIDNEY is registered with ClinicalTrials.gov, NCT03594110.

FINDINGS

Between May 15, 2019, and April 16, 2021, 6609 participants were randomly assigned and followed up for a median of 2·0 years (IQR 1·5-2·4). Prespecified subgroupings by primary kidney disease included 2057 (31·1%) participants with diabetic kidney disease, 1669 (25·3%) with glomerular disease, 1445 (21·9%) with hypertensive or renovascular disease, and 1438 (21·8%) with other or unknown causes. Kidney disease progression occurred in 384 (11·6%) of 3304 patients in the empagliflozin group and 504 (15·2%) of 3305 patients in the placebo group (hazard ratio 0·71 [95% CI 0·62-0·81]), with no evidence that the relative effect size varied significantly by primary kidney disease (pheterogeneity=0·62). The between-group difference in chronic eGFR slopes (ie, from 2 months to final follow-up) was 1·37 mL/min per 1·73 m2 per year (95% CI 1·16-1·59), representing a 50% (42-58) reduction in the rate of chronic eGFR decline. This relative effect of empagliflozin on chronic eGFR slope was similar in analyses by different primary kidney diseases, including in explorations by type of glomerular disease and diabetes (p values for heterogeneity all >0·1).

INTERPRETATION

In a broad range of patients with chronic kidney disease at risk of progression, including a wide range of non-diabetic causes of chronic kidney disease, empagliflozin reduced risk of kidney disease progression. Relative effect sizes were broadly similar irrespective of the cause of primary kidney disease, suggesting that SGLT2 inhibitors should be part of a standard of care to minimise risk of kidney failure in chronic kidney disease.

FUNDING

Boehringer Ingelheim, Eli Lilly, and UK Medical Research Council.

RNA virus diversity in three parasitoid wasps of tephritid flies: insights from novel and known species

IMPORTANCE

Parasitoid wasp populations have developed persistent beneficial symbiotic relationships with several viruses through repeated evolution. However, there have been limited reports on RNA viruses in parasitoid wasps of tephritid flies, a significant pest group affecting fruits and vegetables. This study explores the diversity of RNA viruses in three parasitoid wasps of tephritid flies and highlights the potential biological significance of specific viruses in Diachasmimorpha longicaudata. These findings have important implications for the development of sustainable pest management strategies and the enhancement of artificial rearing techniques for parasitoid wasps.

Fusion dsRNA in targeting salivary protein genes enhance the RNAi-based aphid control

RNA interference (RNAi) is a promising tool for pest control and relies on sequence-specific gene silencing. Salivary proteins are cooperatively secreted into plants to guarantee the feeding of aphids; thus they have potential to develop as selective targets for RNAi-based pest control strategy. For this purpose, we firstly analyzed 18 salivary proteomes of various aphid species, and these salivary proteins can be mainly categorized into seven functional groups. Secondly, we created a work-flow for fusion dsRNA design that can target multiple genes but were selectively safe to beneficial insects. Based on this approach, seven fusion dsRNAs were designed to feed the green peach aphid, which induced a significant reduction in aphid fitness. Among them, ingestion of dsperoxidase induced the highest mortality in aphids, which was also significantly higher than that of traditional dsRNAs in targeting three peroxidases separately. In addition, dsperoxidase-fed green peach aphids triggered the highest H2O2 content of host plants as well as the attraction to natural enemies (ladybeetle and parasitic wasp) but repellent to other control aphids. Our results indicate that the fusion dsRNA design approach can improve aphid control capacity, and the fusion dsRNA targeting salivary protein-encoding genes can enhance the direct and indirect defenses of host plants, thus providing a new strategy for RNAi-based aphid control.

The involvement of systemic RNA interference deficient-1-like (SIL1) in cellular dsRNA uptake in Acyrthosiphon pisum

Systemic RNA interference deficient-1-like (SIL1) is considered a core component in dsRNA uptake in some insect species. Investigation related to the potential function of SIL1 in dsRNA uptake can contribute to a further understanding of RNA interference (RNAi) mechanisms in insects and agricultural pest control. However, the role of SIL1 in dsRNA uptake in insects such as aphids remains controversial. We have thoroughly analyzed the role of SIL1 from the model aphid Acyrthosiphon pisum (ApSIL1) in cellular dsRNA to clarify its function. First, the induced expression of ApSIL1 upon dsRNA oral exposure provided a vital clue for the possible involvement of ApSIL1 in cellular dsRNA uptake. Subsequent in vivo experiments using the RNAi-of-RNAi approach for ApSIL1 supported our hypothesis that the silencing efficiencies of reporter genes were reduced after inhibition of ApSIL1 expression. The impaired biological phenotypes of aphids, including cumulative average offspring, deformities of the nymph, and mortality upon pathogen infection, were then observed in the treatment group. Thereafter, in vitro dual-luciferase reporter assay showed compelling evidence that the luciferin signal was significantly attenuated when dsluciferase or dsGFP was transferred into ApSIL1-transfected Drosophila S2 cells. These observations further confirmed that the signal of Cy3-labeled dsRNA was rapidly attenuated with time in ApSIL1-transfected Drosophila S2 cells. Overall, these findings conclusively establish that ApSIL1 is involved in dsRNA uptake in A. pisum.

GARP: A family of glycine and alanine-rich proteins that helps spider mites feed on plants

Spider mites (Tetranychidae) are destructive agricultural pests which have evolved strategies to overcome plant defenses, such as the ability to puncture the leaves of their hosts to feed. The expression of many genes with unknown functions is altered during feeding, but little is known about the role of these genes in plant-mite interactions. Here, we identified 3 novel gene families through analysis of genomic and transcriptomic data from 3 spider mite species. These GARP family genes encode glycine and alanine-rich proteins; they are present in mites (Acariformes) but absent in ticks (Parasitiformes) in the subclass Acari, indicating that these genes have undergone a significant expansion in spider mites and thus play important adaptive roles. Transcriptomic analysis revealed that the expression of GARP genes is strongly correlated with feeding and the transfer to new hosts. We used RNA interference to silence GARP1d in the two-spotted spider mite Tetranychus urticae, which inhibited feeding and egg laying and significantly increased mortality when the mites were transferred to soybean shoots; a similar effect was observed after TuVATPase was silenced. However, no changes in mite mortality were observed after TuGARP1d-silenced mites were placed on an artificial diet, which was different from the effect of TuVATPase silencing. Our results indicate that GARP family members play important roles in mite-plant interactions. Additional studies are needed to clarify the mechanisms underlying these interactions.

[Analysis on survival time and influencing factors among reported HIV/AIDS in Yunnan Province, 1989-2021]

Objective: To analyze the survival time of reported HIV/AIDS and influencing factors of Yunnan Province from 1989 to 2021. Methods: The data were extracted from the Chinese HIV/AIDS comprehensive response information management system. The retrospective cohort study was conducted. The life table method was applied to calculate the survival probability. Kaplan-Meier was used to draw survival curves in different situations. Furthermore, the Cox proportion hazard regression model was constructed to identify the factors related to survival time. Results: Of the 174 510 HIV/AIDS, the all-cause mortality density was 4.23 per 100 person-years, the median survival time was 20.00 (95%CI:19.52-20.48) years, and the cumulative survival rates in 1, 10, 20, and 30 years were 90.75%, 67.50%, 47.93% and 30.85%. Multivariate Cox proportional risk regression model results showed that the risk of death among 0-14 and 15-49 years old groups were 0.44 (95%CI: 0.34-0.56) times and 0.51 (95%CI:0.50-0.52) times of ≥50 years old groups. The risk for death among the first CD4⁺T lymphocytes counts (CD4) counts levels of 200-349 cells/μl, 350-500 cells/μl and ≥501 cells/μl groups were 0.52 (95%CI: 0.50-0.53) times, 0.41 (95%CI: 0.40-0.42) times and 0.35 (95%CI: 0.34-0.36) times of 0-199 cells/μl groups. The risk of death among the cases that have not received antiretroviral therapy (ART) was 11.56 (95%CI: 11.26-11.87) times. The risk for death among the cases losing to ART, stopping to ART, both losing and stopping ART was 1.66 (95%CI:1.61-1.72) times, 2.49 (95%CI:2.39-2.60) times, and 1.65 (95%CI:1.53-1.78) times of the cases on ART. Conclusions: The influencing factors for the survival time of HIV/AIDS cases were age at diagnosis in Yunnan province from 1989 to 2021. The first CD4 counts levels, antiretroviral therapy, and ART compliance. Early diagnosis, early antiretroviral therapy, and increasing ART compliance could extend the survival time of HIV/AIDS cases.

A pH- and enzymatic-responsive nanopesticide to control pea aphids and reduce toxicity for earthworms

Thiacloprid is a new chlorinated nicotinoid insecticide against stinging-oral pests, such as aphids. It is less toxic to bees but more toxic to earthworms. In this study, a pH- and amylase-responsive MOF (ZIF-8) was constructed for site-specific delivery of thiacloprid to control pea aphids and more safety for earthworms. Thiacloprid from α-cyclodextrin@Thiacloprid@ZIF-8 (α-CD@T@ZIF-8) could be released quickly in pea aphids, which was ascribed to disintegration of ZIF-8 at low pH values in pea aphid intestines and degradation of α-CD under the action of α-amylase. The release results showed a significant pH dependence of α-CD@T@ZIF-8, with an approximately 65 % release amount at pH = 7 and a 95 % release amount at pH = 5 for 7 d. The results of the pot experiment and biosafety showed that for α-CD@T@ZIF-8, 88 % pea aphids could be killed compared with 32 % aphids for commercially available formulation on the 7th day after application. Meanwhile the LC50 of thiacloprid OD was 0.034 μg/cm2 and the LC50 of α-CD@T@ZIF-8 was 0.564 μg/cm2 on earthworms, and it was more safety for pea and lower acute toxicity and enrichment for the earthworms. α-CD@T@ZIF-8 could be used for intelligently controlled release of other insecticides against aphids.

A saliva α-glucosidase MpAgC2-2 enhance the feeding of green peach aphid Myzus persicae via extra-intestinal digestion

Aphids feed on plant phloem sap that contains massive amounts of sucrose; this not only provides vital nutrition for the aphids but also produces high osmotic pressure. To utilize this carbon source and overcome the osmotic pressure, sucrose is hydrolyzed into the monosaccharides, glucose and fructose. In the green peach aphid (Myzus persicae), we show that this process is facilitated by a key α-glucosidase (MpAgC2-2), which is abundant in the aphid salivary gland and is secreted into leaves during feeding. MpAgC2-2 has a pH optimum of 8.0 in vitro, suggesting it has adapted to the environment of plant cells. Silencing MpAgC2-2 (but not the gut-specific MpAgC3-4) significantly increased the amount of sucrose ingested and hindered aphid feeding on the phloem of tobacco seedlings, resulting in a smaller body size, as well as lower α-glucosidase activity and glucose levels. These effects could be rescued by feeding aphids on tobacco plants transiently expressing MpAgC2-2. The transient expression of MpAgC2-2 also led to the hydrolysis of sucrose in tobacco leaves. Taken together, these results demonstrate that MpAgC2-2 is a salivary protein that facilitates extra-intestinal feeding via sucrose hydrolysis. Our findings provide insight into the ability of aphids to digest the high concentration of sucrose in phloem, and the underlying mechanism of extra-intestinal digestion.

Discovery of a widespread presence bunyavirus that may have symbiont-like relationships with different species of aphids

Aphids are important agricultural pests, vectors of many plant viruses and have sophisticated relationships with symbiotic microorganisms. Abundant asymptomatic RNA viruses have been reported in aphids due to the application of RNA-seq, but aphid-virus interactions remain unclear. Bunyavirales is the most abundant RNA virus order, which can infect mammals, arthropods, and plants. However, many bunyaviruses have specific hosts, such as insects. Here, we discovered 18 viruses from 10 aphid species by RNA-seq. Importantly, a widespread presence bunyavirus, Aphid bunyavirus 1 (ABV-1), was determined to have a wide host range, infecting and replicating in all 10 tested aphid species. ABV-1 may be transmitted horizontally during feeding on plant leaves and vertically through reproduction. In a comparison of the physiological parameters of ABV-1^high and ABV-1^low strains of pea aphid, higher ABV-1 titers reduced the total nymphal duration and induced the reproduction. Moreover, viral titer significantly affected the lipid and protein contents in pea aphids. In summary, we proposed that ABV-1 may have stable symbiont-like relationships with aphids, and these observations may provide a new direction for studying bunyaviruses in aphids and establishing a model for virus-aphid interactions.

POS0370 COMPARATIVE RETINOPATHY RISK OF HIGH- VS LOW-DOSE HYDROXYCHLOROQUINE AMONG 4,677 INCIDENT LONG-TERM USERS: EMULATED TARGET TRIAL ANALYSES

Background

Hydroxychloroquine (HCQ) is a key treatment for patients with lupus, but the major long-term toxicity is HCQ retinopathy. A large cross-sectional study found a prevalence of HCQ retinopathy of 7.5% overall and 5 times higher odds associated with HCQ dose >5 mg/kg/day, which led to ophthalmology guidelines recommending the avoidance of HCQ dosing >5 mg/kg.1 However, whether this dosing recommendation is applicable to the future risk of HCQ retinopathy is unknown, as is the incidence of severe bullseye retinopathy vs. the mild, pre-symptomatic stage. Furthermore, recent studies have indicated that the use of lower doses of HCQ may increase the risk of lupus flares and hospitalizations.2

Objectives

To determine the incidence of HCQ retinopathy associated with long-term HCQ use and compare them according to HCQ dose.

Methods

We emulated a hypothetical target trial using observational data3 from the US integrated health network Kaiser Permanente Northern California to compare two HCQ weight-based dosing strategies, >5 vs ≤5 mg/kg/day, based on dispensed tablets per year. A secondary analysis evaluated >80% of prescription days covered by dispensed tablets per year with HCQ dose >5 vs ≤5 mg/kg. We included 4,677 patients who initiated and continued HCQ for at least 5 years between 1997-2020. We emulated randomization of treatment strategy by cloning each subject and assigning a replicate to each treatment group.3 We censored replicates if and when they deviated from the assigned treatment group, assessed as the average dose in the first 5 years and annually thereafter. We used inverse probability weighting to account for censoring. The primary outcome was HCQ retinopathy, assessed by expert adjudication of spectral domain-optical coherence tomography (SD-OCT) and graded by severity. All SD-OCTs were prospectively reviewed by an expert ophthalmologist (RM), and a second expert ophthalmologist (MM) reviewed all abnormal scans and a random subset of normal scans. We assessed intra-rater reliability of SD-OCT findings. We used pooled logistic regression to estimate the cumulative incidence of HCQ retinopathy for each HCQ dose strategy from initiation. The odds ratios approximated hazard ratios (HRs) because the outcome at each one-year time block is <5%.

Results

Among 4,677 patients, the mean age at HCQ initiation was 52 years; 83% were female. The racial/ethnic composition included 51% non-Hispanic White, 19% Hispanic, 14% Asian, and 11% Black patients. 756 (16.2%) and 3,921 (83.8%) patients initiated HCQ with the primary definition of the treatment strategies >5 and ≤5 mg/kg/day, respectively. The weighted kappa was 0.80 for SD-OCT reliability. 164 patients developed HCQ retinopathy (100 mild, 38 moderate, and 26 severe cases). The cumulative incidence of retinopathy over 18 years was 37.6% for >5 and 5.7% for ≤5mg/kg of HCQ in our primary analysis. The corresponding risk was 26.5% for >5 and 3.2% for ≤5 mg/kg in our secondary analysis using >80% of prescription days. Compared with ≤5 mg/kg of HCQ, the HRs of retinopathy were 9.65 (95% CI 5.73-16.65) and 10.79 (95% CI 6.40-20.07) for >5 mg/kg using the primary and secondary definitions of HCQ dose categories, respectively (Figure 1).

Conclusion

The risk of HCQ retinopathy associated with long-term adherence to >5 mg/kg dosing was high, approximately 10 times that of ≤5 mg/kg dosing. However, most cases identified during the study were mild and pre-symptomatic, supporting the value of regular screening. These data should be incorporated into individualized decisions about long-term use of HCQ.

References

[1]Melles RB, Marmor MF. The risk of toxic retinopathy in patients on long-term hydroxychloroquine therapy. JAMA Ophthalmol 2014;132(12):1453-60

[2]Almeida-Brasil CC et al. Flares after hydroxychloroquine reduction or discontinuation: results from the SLICC inception cohort. Ann Rheum Dis 2021 Dec 15, epub ahead of print

[3]Hernán MA, Robins JM. Using Big Data to Emulate a Target Trial When a Randomized Trial Is Not Available. Am J Epidemiol 2016;183(8):758-64

Disclosure of Interests

April Jorge: None declared, Ronald Melles: None declared, Michael Marmor: None declared, Carol Conell: None declared, Baijun Zhou: None declared, Jingbo Niu: None declared, Yuqing Zhang: None declared, Hyon Choi Consultant of: Ironwood, Selecta, Horizon, Takeda, Kowa, and Vaxart., Grant/research support from: Ironwood and Horizon

The Status of Iodine Nutrition after Removing Iodized Salt in High Water Iodine Regions: a Cross-sectional Study in China

Currently, the removal of iodized salt is carried out in high water iodine regions. The present situation of iodine nutrition and the prevalence of thyroid diseases in such regions have not been clearly elucidated. This study aimed to figure out these problems to help render effective measures for cases of abnormal iodine nutrition status. A cross-sectional study was carried out in four areas of Jining and Heze, Shandong Province, China, with different water iodine concentrations (WIC). In total, 1344 adults were enrolled in this study, and data related to their iodine nutrition, thyroid function, and thyroid ultrasonography were collected. Subjects were grouped according to WIC, urine iodine concentration (UIC), serum iodine concentration (SIC), and combined UIC and SIC for analysis. Iodine levels were in excess in the 100 μg/L ≤ WIC < 300 μg/L and WIC ≥ 300 μg/L areas. Compared with the control WIC group (10-100 μg/L), the WIC ≥ 300 μg/L group had a higher prevalence of thyroid autoimmunity (TAI, 21.25% vs. 13.19%, P <0.05), subclinical hypothyroidism (SH, 20.20% vs. 11.96%, P < 0.05), thyroid nodules (TN, 31.75% vs. 18.71%, P < 0.05), and thyroid dysfunction (23.62% vs. 12.26%, P < 0.05). Compared with the UIC control group (100-300 μg/L), high UIC group (≥ 800 μg/L) had a higher prevalence of TN (33.75% vs. 21.14%, P < 0.05) and thyroid dysfunction (25% vs. 14.47%, P < 0.05). Next, compared with the control SIC group (50-110 μg/L), high SIC group (≥ 110 μg/L) had a higher prevalence of TAI (33.80% vs. 14.47%, P < 0.05), SH (23.94% vs. 14.30%, P < 0.05), and thyroid dysfunction (33.80% vs. 15.29%, P < 0.05). Finally, subjects with the highest UIC and the highest SIC also had a higher prevalence of TAI (25.92% vs. 10.97%, P < 0.05), SH (23.45% vs. 10.97%, P < 0.05), TN (34.56% vs. 15.85%, P < 0.05), and thyroid dysfunction (27.16% vs. 13.41%, P < 0.05) than subjects with middle iodine levels. The iodine nutrition of subjects in the WIC ≥ 300 μg/L areas was still in excess after removing iodized salt from their diets. High levels of iodine also increased the prevalence of TAI, SH, TN, and thyroid dysfunction in those areas. Simply removing iodized salt may not be sufficient for high water iodine regions.

Crustacean cardioactive peptide and its receptor modulate the ecdysis behavior in the pea aphid, Acyrthosiphon pisum

Insects must undergo ecdysis for successful development and growth, in which crustacean cardioactive peptide (CCAP) is a master hormone. However, the function of CCAP signaling in pea aphid, Acyrthosiphon pisum, remains unclear. In this study, we determined the sequence of the CCAP precursor and its receptor in A. pisum. We identified the functional receptor ApCCAPR, and then expressed this receptor in Chinese hamster ovary (CHO) cells, which in consequence exhibited high sensitivity to the ApCCAP mature peptide. The ApCCAP transcript was detected in the central nervous system of A. pisum. Neurons containing CCAP were also identified by immunohistochemical staining against insect CCAP. RNAi silencing of ApCCAP or ApCCAP-R signals caused developmental failure during nymph-adult ecdysis. The dsRNA-treated fourth-instar nymphs could not shed their old cuticle and died. Taking these findings together, we conclude that ApCCAP, via the activation of ApCCAP-R, plays an essential role in regulating the process of nymph-adult ecdysis in A. pisum. Our results deepen our understanding of the regulation of early ecdysis in A. pisum.

Mediating Effects of Malnutrition on the Relationship between Depressive Symptoms Clusters and Muscle Function Rather than Muscle Mass in Older Hemodialysis Patients

OBJECTIVES

The purpose of this study was to investigate the association and mediation pathways among muscle mass, muscle function (muscle strength and physical performance), and malnutrition with depressive symptoms clusters in the older hemodialysis patients.

DESIGN

A multi-center cross-sectional study.

SETTING AND PARTICIPANTS

A total of 499 patients aged ≥ 60 on hemodialysis from seven facilities in Shanghai of China from 2020 to 2021.

MEASUREMENTS

Muscle mass was assessed by skeletal muscle index(SMI). Muscle strength was measured by handgrip strength, and physical performance was measured via gait speed and Timed Up and Go Test (TUGT). Nutritional status was assessed by Malnutrition Inflammation Score (MIS). Depressive symptoms were evaluated by the Patient Health Questionnaire-9 (PHQ-9). Logistic regression and mediation analyses fully adjusted for all potential confounding factors.

RESULTS

Among 499 participants (312 men, mean age 69.2±6.6 years), 108 (21.6%) had depressive symptoms. The muscle strength, physical performance and malnutrition were associated with depressive symptoms. Furthermore, malnutrition significantly mediated the association of muscle function with total, cognitive-affective symptoms. The association of the muscle function with somatic symptoms were mediated by the nutritional status. The mediated proportions of malnutrition in the relationship between physical performance and depressive symptoms clusters were stronger in somatic symptoms than in cognitive-affective symptoms.

CONCLUSIONS

Our findings suggest that muscle function rather than muscle mass may contribute substantially to the development of depressive symptoms clusters in the hemodialysis via malnutrition. The malnutrition mediated stronger in the association of muscle function with somatic symptoms. These findings may help guide clinicians to better diagnose and manage depression in the context of concomitant muscle function and malnutrition.

De novo RNA-Seq and Annotation of Sesquiterpenoid and Ecdysteroid Biosynthesis Genes and MicroRNAs in a Spider Mite Eotetranychus kankitus

Eotetranychus kankitus is an important mite pest in citrus, but molecular data on the developmental processes of E. kankitus are lacking. The different development stages mix of E. kankitus was used to sequence for transcriptome and small RNAs to identify genes and predict miRNAs associated with sesquiterpenoid and ecdysteroid biosynthesis and signaling pathways. More than 36 million clean reads were assembled and 67,927 unigenes were generated. Of the unigenes, 19,300 were successfully annotated through annotation databases NR, SwissProt, COG, GO, KEGG, PFAM, and KOG. The transcripts were involved in sesquiterpenoid biosynthesis (11 genes) and ecdysteroid biosynthesis and signaling pathway (13 genes). Another, small RNA library was obtained and 31 conserved miRNAs were identified. Five most abundant miRNAs were Ek-miR-5735, Ek-miR-1, Ek-miR-263a, Ek-miR-184, and Ek-miR-8. The target genes related to sesquiterpenoid and ecdysteroid showed that 10 of the conserved miRNAs could potentially target the sesquiterpenoid and ecdysteroid pathway according to four-prediction software, sRNAT, miRanda, RNAhybrid, and Risearch2. Thus, the results of this study will provide bioinformatics information for further molecular studies of E. kankitus which may facilitate improved pest control strategies.

First-in-human phase 1 study of the anti-TIGIT antibody vibostolimab as monotherapy or with pembrolizumab for advanced solid tumors, including non-small cell lung cancer

BACKGROUND

In this first-in-human phase 1 study, we investigated the safety and efficacy of the anti-TIGIT antibody vibostolimab as monotherapy or in combination with pembrolizumab.

METHODS

Part A enrolled patients with advanced solid tumors and part B enrolled patients with non-small cell lung cancer (NSCLC). Patients received vibostolimab 2.1-700 mg alone or with pembrolizumab 200 mg in part A and vibostolimab 200 mg alone or with pembrolizumab 200 mg in part B. Primary end points were safety and tolerability. Secondary end points included pharmacokinetics and objective response rate (ORR) per RECIST v1.1.

RESULTS

Part A enrolled 76 patients (monotherapy, 34; combination therapy, 42). No dose-limiting toxicities were reported. Across doses, 56% of patients receiving monotherapy and 62% receiving combination therapy had treatment-related adverse events (TRAEs); grade 3-4 TRAEs occurred in 9% and 17% of patients, respectively. The most common TRAEs were fatigue (15%) and pruritus (15%) with monotherapy and pruritus (17%) and rash (14%) with combination therapy. Confirmed ORR was 0% with monotherapy and 7% with combination therapy. In part B, 39 patients had anti-PD-1/PD-L1-naïve NSCLC (all received combination therapy) and 67 had anti-PD-1/PD-L1-refractory NSCLC (monotherapy, 34; combination therapy, 33). In patients with anti-PD-1/PD-L1-naive NSCLC: 85% had TRAEs-the most common were pruritus (38%) and hypoalbuminemia (31%); confirmed ORR was 26%, with responses occurring in both PD-L1-positive and PD-L1-negative tumors. In patients with anti-PD-1/PD-L1‒refractory NSCLC: 56% receiving monotherapy and 70% receiving combination therapy had TRAEs-the most common were rash and fatigue (21% each) with monotherapy and pruritus (36%) and fatigue (24%) with combination therapy; confirmed ORR was 3% with monotherapy and 3% with combination therapy.

CONCLUSION

Vibostolimab plus pembrolizumab was well tolerated and demonstrated antitumor activity in patients with advanced solid tumors, including patients with advanced NSCLC.

Prevalence of a Novel Bunyavirus in Tea Tussock Moth Euproctis pseudoconspersa (Lepidoptera: Lymantriidae)

Euproctis pseudoconspersa is a major pest of tea plants, and also causes a skin rash on workers in tea plantations. Research on virus could provide fundamental insights for classification, genetic diversity, evolution, and host-virus interaction mechanisms. Here, we identified a novel RNA virus, Euproctis pseudoconspersa bunyavirus (Phenuiviridae), and found that it is widely distributed in field populations of E. pseudoconspersa. The replication of virus in E. pseudoconspersa was indicated by Tag-PCR. These results contribute to the classification of bunyaviruses and provide insight into the diversity of commensal E. pseudoconspersa bunyavirus and the host.

Genome-Wide Characterization and Identification of Long Non-Coding RNAs during the Molting Process of a Spider Mite, Panonychus citri

Molting is essential for arthropods to grow. As one of the important arthropod pests in agriculture, key spider mite species (Tetranychus and Panonychus) can normally molt three times from the larva to adult stage within a week. This physiological strategy results in the short lifecycle of spider mites and difficulties in their control in the field. Long non-coding RNAs (lncRNAs) regulate transcriptional editing, cellular function, and biological processes. Thus, analysis of the lncRNAs in the spider mite molting process may provide new insights into their roles in the molting mechanism. For this purpose, we used high-throughput RNA-seq to examine the expression dynamics of lncRNAs and mRNAs in the molting process of different development stages in Panonychus citri. We identified 9199 lncRNAs from 18 transcriptomes. Analysis of the lncRNAs suggested that they were shorter and had fewer exons and transcripts than mRNAs. Among these, 356 lncRNAs were differentially expressed during three molting processes: late larva to early protonymph, late protonymph to early deutonymph, and late deutonymph to early adult. A time series profile analysis of differentially expressed lncRNAs showed that 77 lncRNAs were clustered into two dynamic expression profiles (Pattern a and Pattern c), implying that lncRNAs were involved in the molting process of spider mites. Furthermore, the lncRNA-mRNA co-expression networks showed that several differentially expressed hub lncRNAs were predicted to be functionally associated with typical molting-related proteins, such as cuticle protein and chitin biosynthesis. These data reveal the potential regulatory function of lncRNAs in the molting process and provide datasets for further analysis of lncRNAs and mRNAs in spider mites.

Interactive effects of vitamins A and K3 on laying performance, egg quality, tibia attributes and antioxidative status of aged Roman Pink laying hens

Extending laying cycle is a tendency in hen breeding, but egg quality declines as laying hens age. The present study was conducted to investigate the interactive effects of vitamins A and K₃ on laying performance, egg and tibia quality, and antioxidative status of aged Roman Pink laying hens. In a 3 × 3 factorial arrangement, 1 080 87-week-old laying hens were allocated to nine groups with eight replicates in each group. Deficient, adequate and excess vitamins A (0, 7 000 and 14 000 IU/kg) and K₃ (0, 2.0 and 4.0 mg/kg) were supplemented into a basal diet with 1 320 IU/kg of vitamin A and 0.5 mg/kg of vitamin K₃. After 2 weeks of adaption to basal diet, hens were fed corresponding diets for 8 weeks. Vitamins A and K₃ did not significantly affect the laying performance. However, they showed interactive effects on yolk ratio at week 93 as well as tibia weight and diameter (P < 0.05), and hens fed deficient vitamins A and K₃ had the highest yolk ratio and tibia weight, but the lowest tibia diameter. Compared with deficient addition, adequate or excess vitamins A and K₃ increased yolk color at weeks 93 and 97 (P < 0.05). Compared with hens fed deficient or excess vitamins, hens fed adequate vitamins A and K₃ had higher eggshell strength at week 93 or 97 (P < 0.05). Increasing vitamin A elevated plasma total superoxide dismutase (T-SOD) activity and decreased hepatic glutathione peroxidase (GSH-Px) activity (P < 0.05). Excess vitamin K₃ increased hepatic T-SOD activity (P < 0.05). Vitamins A and K₃ exhibited interaction on the activities of antioxidative enzymes in eggshell gland (P < 0.05), and adequate or excess vitamins A and K₃ increased the activities of GSH-Px, T-SOD and catalase (CAT). Adequate and excess vitamin A up-regulated the mRNA expression of GSH-Px1, GSH-Px3 and SOD1 in eggshell gland (P < 0.05). Vitamins A and K₃ showed interactive effects on CAT mRNA expression in eggshell gland (P < 0.05) and hens fed adequate vitamins A and K₃ had the highest CAT mRNA levels. In conclusion, dietary addition of vitamins A and K₃ improved the eggshell quality and yolk color as well as antioxidative status in eggshell gland of aged laying hens. Adequate vitamins A and K₃ showed beneficial effects and excess levels did not exhibit superior effects.

Involvement of clathrin-dependent endocytosis in cellular dsRNA uptake in aphids

RNAi is an essential technology for studying gene function in eukaryotes, and is also considered to be a potential strategy for pest control. However, the mechanism behind the cellular uptake of dsRNA in aphids, a group of important agricultural sucking pests, remains unknown. Here, using the pea aphid Acyrthosiphon pisum as model for aphids, we identified two core genes of clathrin-dependent endocytosis (CDE), Apchc and Apvha16. We confirmed that expression of Apchc, Apvha16 and RNAi core component genes (ApAgo2, ApDcr2 and ApR2d2) were simultaneously induced at 12 h after feeding dsRNA. By using an RNAi-of-RNAi approach, we demonstrated that suppression of Apchc and Apvha16 transcripts by RNAi significantly impaired RNAi efficiency of selected reporter genes (RGs), including ApGNBP1, Apmts and Aphb, suggesting the involvement of CDE in cellular dsRNA uptake in aphids. Further confirmation was also provided using two inhibitors, chlorpromazine (CPZ) and bafilomycin A1 (BafA1). Administration of CPZ and of BafA1 both led to an impaired silencing efficiency of the RGs in the pea aphid. Finally, these RNAi-of-RNAi results were reconfirmed in the peach aphid Myzus persicae. Taking these findings together, we conclude that CDE is involved in cellular dsRNA uptake in aphids.

Distance to water source in early childhood affects growth: a cohort study

OBJECTIVES

Approximately 165 million children aged <5 years are at risk of low height-for-age. This study explored whether water quality and distance to water source affected short- and long-term growth, and the critical time windows of such effects.

STUDY DESIGN

This study used data from the China Health and Nutrition Survey (CHNS), which was a cohort study performed in 15 Chinese provinces.

METHODS

Data from the CHNS between 1989 and 2011 were examined. Three cohorts of children who were enrolled at 0-2 years of age in 1989, 1993, and 2000 provided sufficient data for this study. Child height was measured by physicians, and household water supply, including the water quality (safe or unsafe) and distance to the source (in-yard or out-yard), was assessed using a questionnaire when the children were 0-2, 4-6, and 11-13 years of age. Multiple regressions were performed to analyse the associations between water quality and distance to the source at various ages, and height at that age and older ages, with and without adjusting for the household water supply at previous ages. Multiple informant models were created using a generalised estimating equation and these were used to assess whether the exposure coefficients were equal across the three age periods.

RESULTS

A total of 1192 children were included. Water quality was not significantly associated with height over the three age periods. An out-yard water source at the age of 0-2 years was not associated with child height at that age, but it was inversely associated with child height at ages 4-6 and 11-13 years (β = -1.605, 95% confidence interval [CI]: -2.490 to -0.720, and β = -2.817, 95% CI: -4.411 to -1.224, respectively), after adjusting for sociodemographic and economic covariates and baseline child height. Distance to the water source at age 4-6 and 11-13 years was not significantly associated with height. However, significant differences were observed in the associations between distance to water source across the three age periods and height at age 4-6 and 11-13 years (p_int = 0.064 and 0.069, respectively).

CONCLUSIONS

Distance to the water source in early, but not later, childhood exerted a long-term effect on child height. When the water quality is good, efforts should be made to shorten the distance to the source to improve child health and growth.

Synthesis of carbon dots@Fe3O4 and their photocatalytic degradation properties to hexaconazole

The CD@Fe₃O₄ photocatalysts were synthesized via hydrothermal synthesis method. The CD@Fe₃O₄ particles were synthesized using Fe₃O₄ as the core and using citric acid and ethylenediamine as a raw material, which were heated to 200 °C for 4 h. The synthesized fluorescent CD@Fe₃O₄ was characterized by HR-TEM, IR and fluorescence spectrophotometer. The HR-TEM results showed CD and Fe₃O₄ nanoparticles were uniform, mono-dispersed sphere or hemisphere particles with an average size of approximately 3 nm, and particle size of CD@Fe₃O₄ were mainly in range of 20-30 nm. XRD results showed the nanoparticles mainly belonged to Fe₃O₄ and CD@Fe₃O₄, which made recycling our photocatalysts possible due to the magnetic performance. On daylight lamp, the half-life of hexaconazole in CD@Fe₃O₄ photocatalysts was about 4 days, and it is lower than half-life (over 100 days) of hexaconazole without CD@Fe₃O₄ photocatalysts.

Sequencing of Transcriptome and Small RNA Revealed the Xenobiotic Metabolism-Related Genes and Potential Regulatory miRNA in Asian Tramp Snail

The Asian tramp snail, Bradybaena similaris (Ferusssac), is an invasive land snail species and has been a rising agricultural pest in south of China. As a pest, it also plays a role in transmission of Angiostrongylus cantonensis. However, present studies on this species are rare and the molecular information is limited. For this purpose, we sequenced the transcriptome and small RNA of B. similaris collected from citrus orchards. In total, 89,747 unigenes with an N50 size of 1287 bp and an average length of 817 bp were generated from ∼8.9 Gb transcriptome and 31 Mb clean reads were generated from ∼36 Mb small RNA library. To demonstrate the usefulness of these two datasets, we analyzed a series of genes associated with xenobiotic metabolism and core RNAi machinery. Analysis of the transcripts resulted in annotation of 126 putative genes encoding cytochrome P450 monooxygenases (CYP, 45), carboxyl/cholinesterases (CCE, 13), glutathione-S-transferases (GST, 24), and ATP-binding cassette transporters (ABC, 44). Analysis of the small RNA detected 42 miRNAs. In addition, four genes involved in small RNA pathways (miRNA, piRNA, and siRNA) were identified, and a total of 430 genes that can be targeted by miRNAs were predicted. Moreover, we found that a few miRNAs could target certain genes involved in xenobiotic metabolism. Therefore, we believe that these two datasets and the characterization of the identified/predicted genes will facilitate the molecular study of this species as well as other land snails with agricultural importance.

Safety and efficacy of quavonlimab, a novel anti-CTLA-4 antibody (MK-1308), in combination with pembrolizumab in first-line advanced non-small-cell lung cancer

BACKGROUND

Quavonlimab (MK-1308), a novel anti-CTLA-4 antibody, in combination with pembrolizumab was investigated in a phase I study.

PATIENTS AND METHODS

Dose-escalation (DE) phase: patients with advanced/metastatic solid tumors received an initial flat dose of quavonlimab as monotherapy [25 mg (cohort 1), 75 mg (cohort 2), or 200 mg (cohort 3)] followed by four treatments of the same quavonlimab dose plus pembrolizumab every 3 weeks (Q3W). Dose-confirmation phase (DC): patients with stage IIIB/IV non-small-cell lung cancer (NSCLC) received first-line quavonlimab [25 mg Q3W (arm A), 25 mg Q6W (arm B), 75 mg Q6W (arm C), or 75 mg Q3W (arm E)] plus pembrolizumab. Primary objectives were safety and tolerability and establishment of the recommended phase II dose (RP2D) of quavonlimab when used with pembrolizumab. Objective response rate (ORR) was a secondary endpoint. Efficacy based on PD-L1 expression, tumor mutational burden (TMB), and changes in circulating CD4+/CD8+ cells were exploratory endpoints.

RESULTS

Thirty-nine patients were enrolled in DE [n = 14 (cohort 1); n = 17 (cohort 2); n = 8 (cohort 3)] and 134 in DC [n = 40 (arm A); n = 40 (arm B); n = 40 (arm C); n = 14 (arm E)]. Maximum-tolerated dose was not reached. Grade 3-5 treatment-related adverse events (AEs; graded according to NCI CTCAE v4.03) occurred in 0%, 23.5%, and 75.0% of patients in DE cohorts 1, 2, and 3, respectively, and 35.0%, 30.0%, 35.0%, and 57.1% of patients in DC arms A, B, C, and E, respectively. Efficacy was observed at all dose levels/schedules in patients with NSCLC. ORRs were 40.0% [95% confidence interval (CI), 24.9-56.7; arm A], 37.5% (95% CI, 22.7-54.2; arm B), 27.5% (95% CI, 14.6-43.9; arm C), and 35.7% (95% CI, 12.8-64.9; arm E). PD-L1 expression and total number of circulating CD4+ cells correlated with ORR.

CONCLUSIONS

Quavonlimab 25 mg Q6W plus pembrolizumab demonstrated similar efficacy and a better safety profile among all quavonlimab doses/schedules evaluated; this regimen was the chosen RP2D.

The PacBio Full-Length Transcriptome of the Tea Aphid as a Reference Resource

The tea aphid, Aphis aurantii, has become one of the destructive pests in tea plantations in the tropics and subtropics. Very few functional studies have so far focused on the developmental and reproductive biology at a molecular level, because of the lack of comprehensive genetic information. Full-length transcriptomes represent a very highly efficient approach to obtain reference gene sequences in non-model insects. In the present study, the transcriptome of A. aurantii was comprehensively sequenced using PacBio Iso-Seq technology. A total of 46.8 Gb nucleotides and 15,938 non-redundant full-length transcripts were obtained, 13,498 (84.69%) of which were annotated into seven databases. Of these transcripts, 2,029 alternative splicing events and 15,223 simple sequence repeats were detected. Among these transcripts, 4,571 (28.68%) and 11,367 (71.32%) were long non-coding RNAs (lncRNAs) and protein-coding genes, respectively. Five hundred and ninety transcription factors were detected. The first full-length transcriptome represents a significant increase in the known genetic information of A. aurantii. It will assist the future functional study of genes involved in its development and reproduction.

The relation of peripheral and central sensitization to muscle co-contraction: the MOST study

OBJECTIVE

To examine the relation of pain sensitization to altered motor activity in knee OA as assessed by hamstrings muscle co-contraction during maximal effort knee extension.

DESIGN

Medial, lateral, and overall hamstring co-contraction was assessed in the Multicenter Osteoarthritis (MOST) Study cohort using electromyography during isokinetic knee extension at 60°/second. Mechanical temporal summation of pain (TS) was assessed at the right wrist and pressure pain thresholds (PPT) were assessed at the patellae; PPTs were categorized into sex-specific tertiles. Muscle co-contraction was categorized into age- and sex-specific tertiles. We evaluated the relation of measures of sensitization to muscle co-contraction using a generalized logistic regression model.

RESULTS

1633 participants were included: mean age and BMI was 67.3 ± 7.7 years and 30.3 ± 5.6 kg/m2, respectively; 58% were female. Presence of TS was associated with higher overall (OR 1.3, 95% confidence interval (CI) (1.0-1.8)), medial (1.4 (1.0-1.9), and lateral (1.3 (1.0, 1.9)) hamstring co-contraction. The lowest PPT tertile (greater sensitivity) was associated with higher overall (1.5 (1.0, 2.3)) and medial (1.5 (1.0, 2.3)) hamstring co-contraction compared with those in the highest PPT tertile.

CONCLUSION

Greater pain sensitization, as assessed by presence of TS at the wrist and low patellar PPT, was associated with greater overall and medial hamstring co-contraction during knee extension. This provides support to the possibility that peripheral and/or central nervous system alterations may not only affect pain sensitivity, but also motor function.

The RNA Virome and Its Dynamics in an Invasive Fruit Fly, Bactrocera dorsalis, Imply Interactions Between Host and Viruses

The oriental fruit fly, Bactrocera dorsalis (Hendel), is an important invasive agricultural insect pest with a wide host range, and has spread around the world over the last century. This evolutionary trait may have arisen primarily from interactions between B. dorsalis and other invertebrates that share the same ecological niches. The invasive behavior of B. dorsalis also frequently exposes them to diverse species of viruses. Thereby, RNA viromes may be useful microbial markers to understand the ecological evolution of B. dorsalis as well as to investigate virus-host interactions. Here, we reported eight novel RNA viruses in B. dorsalis of a lab colony, including four positive-strand RNA viruses, two negative-strand RNA viruses, and two double-stranded RNA viruses using high-throughput sequencing technology. Analysis of the virus-derived small RNAs suggested that most of these viruses may be active and trigger the host antiviral RNAi responses. The viruses were also detected in various geographical populations of B. dorsalis, implying that there is a strong association between the viromes and host. In addition, these viruses infected specific fly tissues, predominately the central nervous system and gut. Furthermore, we explored the dynamics of the viruses when hosts were exposed to short- or long-term stressors, which showed that titers of some viruses were responsively altered in the stressed B. dorsalis. The discovery of these viruses may enrich our understanding of the species diversity of RNA viruses and also provide information on viruses in association with host adaptation in insects.

Gender and age differences in the association between sleep characteristics and fasting glucose levels in Chinese adults

AIM

The present study examined the associations between night-time sleep duration, midday napping duration and bedtime, and fasting glucose levels, and whether or not such associations are dependent on gender and age.

METHODS

This study was a cross-sectional analysis of 172,901 adults aged≥40 years living in mainland China. Sleep duration was obtained by self-reports of bedtime at night, waking-up time the next morning and average napping duration at midday. Fasting plasma glucose (FPG)≥7.0mmol/L was defined as hyperglycaemia. Independent associations between night-time sleep duration, midday naptime duration and bedtime with hyperglycaemia were evaluated using regression models.

RESULTS

Compared with night-time sleep durations of 6-7.9h, both short (<6h) and long (≥8h) night-time sleep durations were significantly associated with an increased risk of hyperglycaemia in women [odds ratio (OR): 1.12, 95% confidence interval (CI): 1.01-1.29 and OR: 1.14, 95% CI: 1.08-1.21, respectively], and revealed a U-shaped distribution of risk in women and no significant association in men. Long midday nap durations (≥1h) were significantly but weakly associated with hyperglycaemia (OR: 1.04, 95% CI: 1.01-1.09) compared with no napping without interactions from gender or age, whereas the association between bedtime and fasting glucose levels did vary according to gender and age.

CONCLUSION

Night-time sleep duration, midday napping duration and bedtime were all independently associated with the risk of hyperglycaemia, and some of the associations between these sleep characteristics and hyperglycaemia were gender- and age-dependent.

RNAi in Insects: A Revolution in Fundamental Research and Pest Control Applications

In this editorial for the Special Issue on 'RNAi in insect pest control', three important applications of RNA interference (RNAi) in insects are briefly discussed and linked to the different studies published in this Special Issue. The discovery of the RNAi mechanism revolutionized entomological research, as it presented researchers with a tool to knock down genes, which is easily applicable in a wide range of insect species. Furthermore, RNAi also provides crop protection with a novel and promising pest control mode-of-action. The sequence-dependent nature allows RNAi-based control strategies to be highly species selective and the active molecule, a natural biological molecule known as double-stranded RNA (dsRNA), has a short environmental persistence. However, more research is needed to investigate different cellular and physiological barriers, such as cellular uptake and dsRNA degradation in the digestive system in insects, in order to provide efficient control methods against a wide range of insect pest species. Finally, the RNAi pathway is an important part of the innate antiviral immune defence of insects, and could even lead to applications targeting viruses in beneficial insects such as honeybees in the future.

Parental silencing of a horizontally transferred carotenoid desaturase gene causes a reduction of red pigment and fitness in the pea aphid

BACKGROUND

Aphids obtained carotenoid biosynthesis genes via horizontal gene transfers from fungi. However, the roles of these genes in the contributions of in aphids'adaptation and whether these genes could be used as RNAi-based pest control targets are not yet clear. Thus, in this study we used parental RNAi to analyze the potential function of a carotenoid desaturase gene (CdeB) by combined molecular and chemical approaches in the pea aphid (Acyrthosiphon pisum).

RESULTS

Transcriptional analyses showed that CdeB was significantly more highly expressed in the red morphs compared to the green ones and was associated with the production of red carotenoid. Co-transferring of pET28a-CdeB (the CdeB gene was cloned into pET28a) and pACCRT-EIB (produced lycopene) showed a deep red color in the bacterial precipitate and produced more of a red pigment, lycopene, in vitro. Parental gene-silencing of CdeB resulted in a lower body color intensity in the treated aphids and following generations in vivo. Interestingly, the dsCdeB treatment also reduced aphid performance as reflected by a delay in nymphal developmental duration, lower weight, smaller number, and altered age structure of the population.

CONCLUSION

Our results demonstrate that CdeB is involved in red color formation and the silencing of this gene by parental RNAi reduced fitness in the pea aphid. The results enhance our understanding of the biosynthesis of carotenoid in aphids and provide insights into the potential ecological significance of carotenoids in the adaptation of the aphid's biology to the environment and developing environmentally friendly control strategies for this pest.

Comparative Insight into the Bacterial Communities in Alate and Apterous Morphs of Brown Citrus Aphid (Hemiptera: Aphididae)

Wing polyphenism (alate and apterous morphs) in aphids is a trade-off between dispersal and reproduction. How bacterial communities are associated with wing polyphenism in aphids is still not clearly understood. This study used 16S rRNA sequencing to examine the differences in diversity of the bacterial community between alate and apterous morphs in Aphis citricidus, the main vector of the Citrus tristeza virus. Eighty-one operational taxonomic units (OTUs) belonging to 37 orders, 34 classes, and 13 phyla were identified from all samples. Among these OTUs, Wolbachia (79.17%), Buchnera (17.64%), and Pseudomonas (2.99%) were the dominant bacterial genera. The diversity of symbionts varied between the two morphs; apterous morphs had more bacterial diversity (69 OTUs belonging to 45 families, 21 classes, and 12 phyla) than alate morphs (45 OTUs belonging to 36 families, 15 classes, and 10 phyla). In addition, the abundance of five OTUs was significantly different between two morphs. Among these OTUs, two Pseudomonas species (Pseudomonas_brenneri [OTU21] and unclassified_Pseudomonas [OTU13]) represented a high proportion (3.93% and 2.06%) in alate morphs but were present in low abundance (0.006% and 0.002%) in apterous morphs. RT-qPCR showed consistent results with high-throughput DNA sequencing. The preliminary survey showed the difference in composition and frequency of bacteria between alate and apterous morphs. Thus, the results contribute to anew insight of microorganisms that may be involved in wing dimorphism and helpful for controlling the dispersal of this pest through artificial elimination or reinfection of bacterial symbionts or targeting symbiosis-related host genes by RNA interference in future.

Divergent molecular evolution in glutathione S-transferase conferring malathion resistance in the oriental fruit fly, Bactrocera dorsalis (Hendel)

Insect glutathione S-transferases (GSTs) are important in insecticide detoxification and Insect-specific GSTs, Epsilon and Delta, have largely expanded in insects. In this study, we functionally expressed and characterized an epsilon class GST gene (BdGSTe8), predominant in the adult Malpighian tubules of Bactrocera dorsalis. This gene may be associated with malathion resistance based on transcriptional studies of resistant and susceptible strains. RNA interference-mediated knockdown of this gene significantly recovered malathion susceptibility in the adults of a malathion-resistant strain, and overexpression of BdGSTe8 enhanced resistance in transgenic Drosophila. Analysis of BdGSTe8 polymorphism showed that several point mutations may be associated with metabolic resistance to malathion. A cytotoxicity assay in Escherichia coli indicated that both of the recombinant BdGSTe8 proteins may play a functional role in protecting cells from toxicity. The allele of BdGSTe8-B conferred higher levels of malathion detoxification capability. Liquid chromatography and ultra-performance liquid chromatography-tandem mass spectrometry analysis showed that the BdGSTe8-A allele did not metabolize malathion directly. However, the BdGSTe8-B allele was involved in the direct metabolism of malathion, which was caused by a mutation in V128A. Further analysis of the sequence suggests that BdGSTe8 evolved rapidly. It maybe play the role of a backup gene and could become a new gene in the future in order to retain the ability of detoxification of malathion, which was driven by positive selection. These results suggest that divergent molecular evolution in BdGSTe8 has played a role in metabolic resistance to malathion in B. dorsalis.

First Report of a Mesonivirus and Its Derived Small RNAs in an Aphid Species Aphis citricidus (Hemiptera: Aphididae), Implying Viral Infection Activity

We report a new positive-sense single-stranded RNA (ss RNA+) virus from the brown citrus aphid Aphis citricidus. The 20,300 nucleotide (nt)-long viral genome contains five open-reading frames and encodes six conserved domains (TM2, 3CLpro, TM3, RdRp, Zm, and HEL1). Phylogenetic analysis and amino acid sequence analysis revealed this virus might belong to an unassigned genus in the family Mesoniviridae. The presence of the virus was also confirmed in the field population. Importantly, analysis of the virus-derived small RNAs showed a 22-nt peak, implying that viral infection triggers the small interfering RNA pathway as antiviral immunity in aphids. This is the first report of a mesonivirus in invertebrates other than mosquitoes.