Pyriproxyfen enhances germline stem cell proliferation and reduces reproduction in Drosophila by up-regulating juvenile hormone signaling.

BACKGROUND: Pyriproxyfen is an insect growth regulator (IGR) that is effective against various types of insect pests. However, the molecular mechanism underlying pyriproxyfen effects on insect reproduction remains unclear. Thus, in this study, we attempted to uncover the mechanisms underlying the impact of pyriproxyfen on the reproductive system of the model organism Drosophila melanogaster. RESULTS: A significant decrease in Drosophila reproduction was observed after pyriproxyfen treatment. The juvenile hormone (JH) titer was significantly increased (120.4%) in the ovary samples of pyriproxyfen-treated flies. Likewise, the concentrations of key enzymes and the expression of key genes related to the JH signaling pathway were also increased in the pyriproxyfen-treated group compared with the control group. Furthermore, pyriproxyfen treatment significantly increased (15.6%) the number of germline stem cells (GSCs) and significantly decreased (17%) the number of cystoblasts (CBs). However, no significant differences were observed in the number of somatic cells. We performed RNA interference (RNAi) on five key genes (Met, Tai, gce, ftz-f1, and hairy) related to the JH signaling pathway in germ cells using the germ cell-specific Gal4 driver. Interestingly, RNAi of the selected genes significantly decreased the number of both GSCs and CBs in pyriproxyfen-treated transgenic flies. These results further validate that pyriproxyfen enhances GSC proliferation by up-regulating JH signaling. CONCLUSION: Our results indicate that pyriproxyfen significantly decreases reproduction by affecting germ cells in female adult ovaries. The effect of pyriproxyfen on germ cell proliferation and differentiation is mediated by an increase in JH signaling. This study has significant implications for optimizing pest control strategies, developing sustainable agriculture practices, and understanding the mechanism of insecticide action. © 2024 Society of Chemical Industry.

Bioorthogonal click labeling of an amber-free HIV-1 provirus for in-virus single molecule imaging.

Structural dynamics of human immunodeficiency virus 1 (HIV-1) envelope (Env) glycoprotein mediate cell entry and facilitate immune evasion. Single-molecule FRET using peptides for Env labeling revealed structural dynamics of Env, but peptide use risks potential effects on structural integrity/dynamics. While incorporating noncanonical amino acids (ncAAs) into Env by amber stop-codon suppression, followed by click chemistry, offers a minimally invasive approach, this has proved to be technically challenging for HIV-1. Here, we develope an intact amber-free HIV-1 system that overcomes hurdles of preexisting viral amber codons. We achieved dual-ncAA incorporation into Env on amber-free virions, enabling single-molecule Förster resonance energy transfer (smFRET) studies of click-labeled Env that validated the previous peptide-based labeling approaches by confirming the intrinsic propensity of Env to dynamically sample multiple conformational states. Amber-free click-labeled Env also enabled real-time tracking of single virion internalization and trafficking in cells. Our system thus permits in-virus bioorthogonal labeling of proteins, compatible with studies of virus entry, trafficking, and egress from cells.

Smoothened antagonist sonidegib affects the development of D. melanogaster larvae via suppression of epidermis formation.

Hedgehog (Hh) signaling is essential for the regulation of embryonic growth and development, the maintenance of stem cell autostasis, and tissue formation, whether in vertebrates or invertebrates. However, exploration into the Hh pathway antagonists in Drosophila or other pests of agricultural importance has been scant. In order to gain a better understanding of the potential utility of the antagonists in insect investigations, a conventional Hh antagonist, sonidegib, was used to evaluate the effects on the development of Drosophila larvae. The results showed that early instar larvae exposed to sonidegib exhibited new epidermal abnormalities and decreased motility after molting. Transcriptome analysis revealed that Sonidegib had a profound effect on chitin-based cuticle development throughout all stages of larvae. Physiological experiments revealed that sonidegib suppressed the epidermis formation and decreased the chitin content. The results of this study shed new light on the potential use of Hh antagonists in agricultural pest management.

Head-to-head immunogenicity comparison of an Escherichia coli-produced 9-valent human papillomavirus vaccine and Gardasil 9 in women aged 18-26 years in China: a randomised blinded clinical trial.

BACKGROUND: An Escherichia coli-produced human papillomavirus (HPV) 16 and 18 bivalent vaccine (Cecolin) was prequalified by WHO in 2021. This study aimed to compare the immunogenicity of the E coli-produced HPV 9-valent vaccine Cecolin 9 (against HPV 6, 11, 16, 18, 31, 33, 45, 52, and 58) with Gardasil 9. METHODS: This was a randomised, single-blind trial conducted in China. Healthy non-pregnant women aged 18-26 years, who were not breastfeeding and with no HPV vaccination history, were enrolled in the Ganyu Centre for Disease Control and Prevention (Lianyungang City, Jiangsu Province, China). Women were stratified by age (18-22 years and 23-26 years) and randomly assigned (1:1) using a permutated block size of eight to receive three doses of Cecolin 9 or Gardasil 9 at day 0, day 45, and month 6. All participants, as well as study personnel without access to the vaccines, were masked. Neutralising antibodies were measured by a triple-colour pseudovirion-based neutralisation assay. The primary outcomes, seroconversion rates and geometric mean concentrations (GMCs) at month 7, were analysed in the per-protocol set for immunogenicity (PPS-I). Non-inferiority was identified for the lower limit of the 95% CI of the GMC ratio (Cecolin 9 vs Gardasil 9) at a margin of 0·5 and a seroconversion rate difference (Cecolin 9-Gardasil 9) at a margin of -5%. This study was registered at ClinicalTrials.gov (NCT04782895) and is completed. FINDINGS: From March 14 to 18, 2021, a total of 553 potential participants were screened, of which 244 received at least one dose of Cecolin 9 and 243 received at least one dose of Gardasil 9. The seroconversion rates for all HPV types in both groups were 100% in the PPS-I, with the values of the lower limits of 95% CIs for seroconversion rate differences ranging between -1·8% and -1·7%. The GMC ratios of five types were higher than 1·0, with the highest ratio, for HPV 58, at 1·65 (95% CI 1·38-1·97), and those of four types were lower than 1·0, with the lowest ratio, for HPV 11, at 0·79 (0·68-0·93). The incidence of adverse reactions in both groups was similar (43% [104/244] vs 47% [115/243]). INTERPRETATION: Cecolin 9 induced non-inferior HPV type-specific immune responses compared with Gardasil 9 and is a potential candidate to accelerate the elimination of cervical cancer by allowing for global accessibility to 9-valent HPV vaccinations, especially in low-income and middle-income countries. FUNDING: National Natural Science Foundation, Fujian Provincial Natural Science Foundation, Xiamen Science and Technology Plan Project, Fundamental Research Funds for the Central Universities, CAMS Innovation Fund for Medical Sciences of China, and Xiamen Innovax.

Safety of hepatitis E vaccination for pregnancy: a post-hoc analysis of a randomized, double-blind, controlled phase 3 clinical trial.

Special attention has been paid to Hepatitis E (HE) prophylaxis for pregnant women due to poor prognosis of HE in this population. We conducted a post-hoc analysis based on the randomized, double-blind, HE vaccine (Hecolin)-controlled phase 3 clinical trial of human papillomavirus (HPV) vaccine (Cecolin) conducted in China. Eligible healthy women aged 18-45 years were randomly assigned to receive three doses of Cecolin or Hecolin and were followed up for 66 months. All the pregnancy-related events throughout the study period were closely followed up. The incidences of adverse events, pregnancy complications, and adverse pregnancy outcomes were analysed based on the vaccine group, maternal age, and interval between vaccination and pregnancy onset. During the study period, 1263 Hecolin receivers and 1260 Cecolin receivers reported 1684 and 1660 pregnancies, respectively. The participants in the two vaccine groups showed similar maternal and neonatal safety profiles, regardless of maternal age. Among the 140 women who were inadvertently vaccinated during pregnancy, the incidences of adverse reactions had no statistical difference between the two groups (31.8% vs 35.1%, p = 0.6782). The proximal exposure to HE vaccination was not associated with a significantly higher risk of abnormal foetal loss (OR 0.80, 95% CI 0.38-1.70) or neonatal abnormality (OR 2.46, 95% CI 0.74-8.18) than that to HPV vaccination, as did distal exposure. Significant difference was not noted between pregnancies with proximal and distal exposure to HE vaccination. Conclusively, HE vaccination during or shortly before pregnancy is not associated with increased risks for both the pregnant women and pregnancy outcomes.

Synergistic effects of chlorantraniliprole and camptothecin on physiological impairments, histopathological, biochemical changes, and genes responses in the larvae midgut of Spodoptera frugiperda.

Spodoptera frugiperda is an economically important agricultural pest and poses a serious threat to food security globally. Its management is gravely challenged by its high polyphagous nature, strong migratory ability, and massive fecundity. Chlorantraniliprole (CHL) is widely utilized in controlling S. frugiperda, its intensive application and over-reliance pose adverse health risks, development of resistance, toxicity to beneficial insects, natural enemies, and environmental contamination. To address S. frugiperda resistance to CHL and its inherent challenges, this study explores the synergistic effects of camptothecin (CPT) with CHL in its management. The binary mixed adversely induced the larvae weight and mortality when compared to single-treated. CHL + CPT (1:20 mg/L) had the highest larvae mortality of (73.80 %) with a high antagonistic factor (0.90), while (1:10 mg/L) with (66.10%) mortality exhibited a high synergistic factor (1.43). Further, CHL + CPT (1:10 mg/L) considerably altered the midgut epithelial cell, peritrophic membrane, microvilli, basement membrane, and regenerative cells. For biochemical analysis, CHL + CPT (1:10 mg/L) significantly decreased glutathione-S-transferase (1-chloro-2,4-dinitrobenzene CDNB) and cytochrome P450 (7-ethoxycoumarin O-deethylation) activities in the midgut in a dose and time dependent manner. Based on RNA-Seq analysis, a total of 4,373 differentially expressed genes (DEGs) were identified from the three treatments. CPT vs CK (Control) had 1694 (968 up-, 726 down-regulated), CHL vs CK with 1771 (978 up-, 793 down-regulated), and CHL + CPT vs CK had 908 (394 up-, 514 down-regulated) DEGs. The enrichment analysis disclosed significant pathways such as metabolism of xenobiotics by cytochrome P450, glutathione metabolism, TOLL and IMD (Immune Deficiency) signaling pathway, longevity regulating pathway. This study provides basis to expatiate on the molecular toxicological mechanism of CHL + CPT in management of fall armyworm.

Camptothecin Effectively Regulates Germline Differentiation through Bam-Cyclin A Axis in Drosophila melanogaster.

Camptothecin (CPT), first isolated from Chinese tree Camptotheca acuminate, produces rapid and prolonged inhibition of DNA synthesis and induction of DNA damage by targeting topoisomerase I (top1), which is highly activated in cancer cells. CPT thus exhibits remarkable anticancer activities in various cancer types, and is a promising therapeutic agent for the treatment of cancers. However, it remains to be uncovered underlying its cytotoxicity toward germ cells. In this study we found that CPT, a cell cycle-specific anticancer agent, reduced fecundity and exhibited significant cytotoxicity toward GSCs and two-cell cysts. We showed that CPT induced GSC loss and retarded two-cell cysts differentiation in a niche- or apoptosis-independent manner. Instead, CPT induced ectopic expression of a differentiation factor, bag of marbles (Bam), and regulated the expression of cyclin A, which contributed to GSC loss. In addition, CPT compromised two-cell cysts differentiation by decreasing the expression of Bam and inducing cell arrest at G1/S phase via cyclin A, eventually resulting in two-cell accumulation. Collectively, this study demonstrates, for the first time in vivo, that the Bam-cyclin A axis is involved in CPT-mediated germline stem cell loss and two-cell cysts differentiation defects via inducing cell cycle arrest, which could provide information underlying toxicological effects of CPT in the productive system, and feature its potential to develop as a pharmacology-based germline stem cell regulation agent.

Cyromazine affects the ovarian germ cells of Drosophila via the ecdysone signaling pathway.

Cyromazine, an insect growth regulator, has been extensively used against the insect pests of livestock and households. Previously, it was observed that the continuous selection of cyromazine from the larval to the adult stage decreased the number of germline stem cells (GSCs) and cystoblasts (CBs) in the adult ovary. In addition, in this study, we observed that the number of primordial germ cells (PGCs) was also decreased in the larval ovary after treatment with cyromazine. However, the mechanism by which it affects the germ cells is yet to be explored. Consequently, to deeply investigate the effects of cyromazine on the germ cells, we performed tissue-specific RNA sequencing. Bioinformatics analysis revealed that the ecdysone signaling pathway was significantly influenced under cyromazine stress. Based on that, we screened and selected 14 ecdysone signaling responsive genes and silenced their expression in the germ cells only. Results of that showed a considerable reduction in the number of germ cells. Furthermore, we mixed exogenous 20E with the cyromazine-containing diet to rescue the ecdysone signaling. Our results supported that the application of exogenous 20E significantly rescued the germ cells in the transgenic lines. Therefore, this implies that the cyromazine decreased the number of germ cells by affecting the ecdysone signaling pathway.

Detecting Aflatoxin B1 in Peanuts by Fourier Transform Near-Infrared Transmission and Diffuse Reflection Spectroscopy.

Aflatioxin B1 (AFB1) has been recognized by the International Agency of Research on Cancer as a group 1 carcinogen in animals and humans. A fast, batch, and real-time control and no chemical pollution method was developed for the discrimination and quantification prediction of AFB1-infected peanuts by applying Fourier transform near-infrared (FT-NIR) coupled with chemometrics. Initially, the near-infrared transmission (NIRT) and diffuse reflection (NIRR) modules were applied to collect spectra of the samples. The principal component analysis (PCA) method was employed to extract the characteristic wavelength, followed by different preprocessing methods (seven methods) to build an effective linear discriminant analysis (LDA) classification and partial least squares (PLS) quantification models. The results showed that, for both the NIRT or NIRR modules, the LDA classification models satisfactorily distinguished peanuts infected with AFB1 or from those not infected, with external validation showing a 100% correct identification rate and a 0% misjudgment rate. In addition, combined with the concentration of AFB1 in peanuts determined by enzyme-linked immunoassay assay, the best partial least squares (PLS) models were established, with a combination of the first derivative and the Norris derivative filter smoothing pretreatment (Rc2 = 0.937 and 0.984, RMSECV = 3.92% and 2.22%, RPD = 3.98 and 7.91 for NIRR and NIRT, respectively). The correlation coefficient between the predicted value and the reference value in the external verification was 0.998 and 0.917, respectively. This study highlights that both spectral acquisition modules meet the requirements of online, rapid, and accurate identification of peanut AFB1 infection in the early stages.

Prospects of Botanical Compounds and Pesticides as Sustainable Management Strategies Against Spodoptera frugiperda.

Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) (fall armyworm) is an extremely destructive insect pest that causes crop losses, especially cereal production across the world. Its management is challenged by its high migratory ability, polyphagous nature, high fecundity level, and short life cycle. It has become a serious threat across the globe that requires proactive and coordinated regional and global interventions. Although synthetic insecticides have been widely utilized to control the pest, there are numerous inherent challenges associated with the overreliance and overuse of these chemicals, e.g., toxicity to humans, destruction of natural pest enemies and pollinators, environmental and food contamination, pest resurgence, secondary pest outbreaks, and resistance development. Plant-derived pesticides such as Azadirachta indica, Eucalyptus globulus, Jatropha curcas, Lantana camara, Phytolacca dodecandra, and Piper guineense have been evaluated under laboratory, greenhouse, and field conditions to control S. frugiperda. We are certain that the substantial potential of these plants under field conditions could be enhanced and promoted together with existing plant-based products (registered) for use against S. frugiperda as an alternative in integrated pest management schemes. Therefore, this review highlights challenges and prospects that will help refocus and increase research attention on the development and application of botanical pesticides under field conditions rather than only under laboratory and control conditions to increase the commercialization and adoption rate of this technology across the globe.

Cyromazine Effects the Reproduction of Drosophila by Decreasing the Number of Germ Cells in the Female Adult Ovary.

In the present study, we observed a 58% decrease in the fecundity of Drosophila melanogaster, after treatment with the cyromazine. To further elucidate the effects of cyromazine on reproduction, we counted the number of both germline stem cells (GSCs) and cystoblasts (CBs) in the ovary of a 3-day-old adult female. The results showed a significant decrease in the number of GSCs and CBs as compared to the control group. The mode of action of cyromazine is believed to be through the ecdysone signaling pathway. To further support this postulate, we observed the expression of key genes involved in the ecdysone signaling pathway and also determined the ecdysone titer from cyromazine-treated ovaries. Results indicated a significant decrease in the expression of ecdysone signaling-related genes as compared to the control group. Furthermore, the titer of the ecdysone hormone was also markedly reduced (90%) in cyromazine-treated adult ovaries, suggesting that ecdysone signaling was directly related to the decrease in the number of GSCs and CBs. However, further studies are required to understand the mechanism by which cyromazine affects the GSCs and CBs in female adult ovaries.

Risk of hepatocellular carcinoma in antiviral treatment-naïve chronic hepatitis B patients treated with entecavir or tenofovir disoproxil fumarate: a network meta-analysis.

BACKGROUND: Long-term antiviral treatments are associated with a significantly lower hepatocellular carcinoma (HCC) incidence in chronic hepatitis B (CHB) patients by reducing HBV DNA concentrations. However, it is still controversial whether antiviral strategies affect HCC development in antiviral treatment-naïve CHB patients. This study aimed to estimate the incidence of HCC in antiviral treatment-naïve CHB patients who were treated with Entecavir (ETV) and Tenofovir Disoproxil Fumarate (TDF) and compare the efficacy of two treatment regimens in HCC reduction. METHODS: The PubMed, Embase, China National Knowledge Infrastructure, and Wanfang databases were systematically searched until June 24, 2021. The pooled incidence and 95% confidence interval of HCC were calculated by the Freeman-Tukey double arcsine transformation method. The efficacies of ETV and TDF treatments in HCC reduction were compared through a network meta-analysis. RESULTS: A total of 27 studies were identified as eligible for this systematic review. The incidence densities in the ETV and TDF treatment groups were 2.78 (95% CI: 2.21-3.40) and 2.59 (95% CI: 1.51-3.96) per 100 persons-year among patients with preexisting cirrhosis and 0.49 (95% CI: 0.32-0.68) and 0.30 (95% CI: 0.06-0.70) per 100 persons-year among patients without preexisting cirrhosis. As the proportion of CHB patients with preexisting cirrhosis increased, the incidence density of HCC also increased gradually. Compared with other Nucleos(t)ide analogs (NAs) treatments, ETV and TDF treatments significantly lowered the risk of HCC, with hazard ratios (HRs) of 0.60 (95% CI: 0.40-0.90) and 0.56 (95% CI: 0.35-0.89), respectively. However, there was no difference in the incidence density of HCC between ETV and TDF treatments (HR = 0.92, 95% CI: 0.71-1.20) regardless of preexisting cirrhosis. CONCLUSION: ETV and TDF treatments were associated with significantly lower risks of HCC than other NAs treatments. However, no difference was observed between ETV and TDF treatments in the risk of HCC development regardless of preexisting cirrhosis among treatment-naïve CHB patients.

Synergistic effects of botanical curcumin-induced programmed cell death on the management of Spodoptera litura Fabricius with avermectin.

Chemical pesticides and adjuvants have caused many negative effects. Botanical compounds provide solutions for the development of environment friendly pesticides and the management of increasing pest resistance. Curcumin, a natural polyphenol, showed synergistic effects on avermectin upon the destructive agricultural pest, Spodoptera litura. However, the botanical synergist and its relevant mechanisms remain unclear. In the article, curcumin significantly enhanced the growth inhibition and midgut structural damage of avermectin on the larvae of S. litura, and the synergistic effects were confirmed with pot experiments. There were only a few influences on the gene expression of avermectin targets, while apoptotic and autophagic related genes and proteins were accumulated in the avermectin/curcumin mixed regent (0.013/0.0013 µg/mL) treated group. Moreover, the potential mechanism was explored with an in vitro model, insect Spodoptera frugiperda Sf9 cell line. Morphology observation featured the damage on cells and Hoechst33258 staining revealed the fragments of DNA after treating with the avermectin/curcumin mixed regent (10/1 µg/mL). Dansylcadaverine and LysoTracker staining, as well as the gene expressions, supposed that curcumin exhibited autophagy inducing effects and the mixed regent possessed a higher ability to induce apoptosis and autophagy. All these results suggested that the synergistic effects of curcumin on the pest management of avermectin potentially mainly derived from the enhancement of programed cell death. It provides new sights for the application of natural compounds in integrated pest management and enriches examples of synergistic mechanisms.

Metallization and superconductivity in methane doped by beryllium at low pressure.

As one of the simplest hydrocarbons, methane (CH4) has great potential in the research of superconductors. However, the metallization of CH4 has been an issue for a long time. Here, we report the structure, metallization, and superconductivity of CH4 doped by Be at low pressures, based on first-principles calculations. The result shows that the thermodynamically stable BeCH4 with P1[combining macron] space-group can transform into a metal at ambient pressure. This ternary hydride BeCH4 exhibits a superconductivity of ∼6 K below 25.6 GPa. Interestingly, the superconducting critical temperature of BeCH4 can reach ∼30 K at 80 GPa in the form of an a-P1 space-group phase. The charge transfer from Be to CH4 molecules plays an important role in the superconductivity. Our results present a novel way to realize the metallization of methane at relative pressures and indicate that the doped methane is a potential candidate for seeking high temperature and low pressure superconductivity.

Natural ß-carboline alkaloids regulate the PI3K/Akt/mTOR pathway and induce autophagy in insect Sf9 cells.

The ß-carboline alkaloids are a large group of naturally occurring and synthetic indole alkaloids with remarkable pharmacological properties. Furthermore, these alkaloids have also been reported to be effective agents for controlling many pests and plant pathogenic nematodes. However, studies on these potential insecticidal components are scarce. The previous finding that these bioactive compounds can induce programmed cell death in cancer cell lines provided a new insight for exploration of their toxicological mechanisms on insects. In the present study, the cytotoxicity of five natural harmala alkaloids was measured, and the autophagy-inducing effect was confirmed in the Spodoptera frugiperda Sf9 cultured cell line. The results demonstrated that these alkaloids inhibited the proliferation of Sf9 cells in a dose- and time-dependent manner, and the unsaturated ß-carboline alkaloids, harmine and harmol, exhibited stronger autophagy induction activity based on monodansylcadaverineand LysoTracker Red staining. Many autophagy-related genes were increased after ß-carbolines treatment at the RNA level, and the protein expression of Sf-Atg8 was also confirmed to increase after treatment. In addition, the primary autophagic signaling pathway, the PI3K/Akt/mTOR pathway, was altered during the procedure. Furthermore, experiments with special inhibitors and activators were performed to confirm the effect of ß-carbolines on this pathway. The results suggested that the PI3K/Akt/mTOR pathway primarily regulated harmine-induced autophagy in insect cells, and this finding may potentially benefit the application of these promising bioactivity components.

Effects of 60Co-γ radiation on testis physiological aspects of Plutella xylostella (Linnaeus).

The diamondback moth, Plutella xylostella (Linnaeus), is one of the notorious pests causing substantial loses to many cruciferous vegetables across the nations. Sterile insect technique (SIT) is considered as an effective bio-control agent for controlling numerous lepidopteran pests. We searched the deformity spermatozoon and sperm bundles of diamondback moth. In our research, 200 Gy and 400 Gy 60Co-γ radiation doesn't alter the number of apyrene and eupyrene sperm bundles in testis. However, the ratio of abnormal eupyrene sperm bundles was increasing with radiation dosage. The malformation of mitochondrial derivatives is characterized by "V" shape with 400 Gy. Also, the results showed that the expression of caspase-3 with 200 Gy was down-regulated, but was obviously up-regulated after 400 Gy radiation. Thus the present research investigation highlights that the 60Co-γ radiation treatments alters the physiological development of diamondback moth testis.

Large-scale synthesis of single-crystalline self-standing SnSe2 nanoplate arrays for wearable gas sensors.

Advances in two-dimensional semiconducting thin films enable the realization of wearable electronic devices in the form factor of flexible substrate/thin films that can be seamlessly adapted in our daily lives. For wearable gas sensing, two-dimensional materials, such as SnSe2, are particularly favorable because of their high surface-to-volume ratio and strong adsorption of gas molecules. Chemical vapor deposition and liquid/mechanical exfoliation are the widely applied techniques to obtain SnSe2 thin films. However, these methods normally result in non-uniform and isolated flakes which cannot apply to the practical industrial-scale wearable electronic devices. Here, we demonstrate large-scale (10 cm × 10 cm), uniform, and self-standing SnSe2 nanoplate arrays by co-evaporation process on flexible polyimide substrates. Both structural and morphological properties of the resulting SnSe2 nanoplates are systematically investigated. Particularly, the single-crystalline SnSe2 nanoplates are achieved. Furthermore, we explore the application of the polyimide/SnSe2 nanoplate arrays as wearable gas sensors for detecting methane. The wearable gas sensors show high sensitivity, fast response and recovery, and good uniformity. Our approach not only provides an efficient technique to obtain large-area, uniform and high-quality single-crystalline SnSe2 nanoplates, but also impacts on the future developments of layered metal dichalcogenides-based wearable devices.

Proteomic Profiling Analysis of Male Infertility in Spodoptera Litura Larvae Challenged with Azadirachtin and its Potential-Regulated Pathways in the Following Stages.

Biopesticides are considered as an alternative to synthetic pesticide with a focus on increasing agricultural productivity as well as maintaining the ecosystem. Prior to application, its potential mechanism should be clearly addressed. Here, the effects of azadirachtin on the reproductive behavior in male Spodoptera litura (Fabricius) are determined. To further explore its molecular mechanism, an iTRAQ (isobaric tags for relative and absolute quantitation) based approach is applied to identify the differentially expressed proteins regulated by azadirachtin at two developmental stages. The results demonstrate that many proteins in the pathway of focal adhesion are regulated to exert influences in detachment of cell attachment, the loss of cell-cell interactions and inducing apoptosis at pupal stage, and many proteins in adenosine monophosphate-activated protein kinase pathway are also changed at the adult stage after azadirachtin-treatment as larvae. Moreover, based on their important roles, it is suggested that some proteins, such as ACTB-G1, ste20-related adaptor protein alpha, and regulatory-associated protein of mTOR (mTORC1) could serve as potential target proteins of azadirachtin to induce male infertility. The results of this study could provide evidence to illuminate the mechanism of male infertility induced by azadirachtin and potential targets for the development of environmentally friendly pesticides.

Silencing of Rieske Iron-Sulfur Protein Impacts Upon the Development and Reproduction of Spodoptera exigua by Regulating ATP Synthesis.

Rieske iron-sulfur protein (RISP) is a key protein subunit of mitochondrial complex III which plays an important role in the respiratory electron transport chain. The complete cDNA of RISP was cloned from Spodoptera exigua by real time quantitative PCR and rapid-amplification of cDNA ends (RACE) technology and named as SeRISP (GenBank Accession Number: JN992290). Multiple alignments and the creation of a phylogenetic tree revealed that RISPs are highly conserved among different insects, and the highly conserved region of RISPs is mainly located at the C-terminal which serves as the functional domain. Expression pattern analysis demonstrated that SeRISP is expressed in all developmental stages of S. exigua; the expression levels increased during larval growth, remained stable during development from fourth instar to pupa and reached a peak in the adult. In addition, SeRISP was significantly suppressed at both the mRNA and protein levels by feeding the instar stage with dsRNA; levels of suppression increased with increasing dsRNA concentration and continuous treatment time. The silencing of SeRISP in larvae led to the significant inhibition of ATP synthesis and larval growth, which could result in energy reserve deficiency in pupae and the suppression of fecundity and hatchability in adults. Our findings confirmed that it is possible to silence target genes in S. exigua by simple dsRNA feeding, and provided evidence of the essential role of RISP in the process of ATP synthesis, growth and reproduction.

Superconductivity in solid benzene molecular crystal.

Light-element compounds hold great promise of high critical temperature superconductivity judging from the theoretical perspective. A hydrogen-rich material, benzene, is such a kind of candidate but also an organic compound. A series of first-principles calculations are performed on the electronic structures, dynamics properties, and electron-phonon interactions of solid benzene at high pressures. Benzene is found to be dynamically stable in the pressure range of 180-200 GPa and to exhibit superconductivity with a maximum transition temperature of 20 K at 195 GPa. The phonon modes of carbon atoms are identified to mainly contribute to the electron-phonon interactions driving this superconductivity. The predicted superconductivity in this simplest pristine hydrocarbon shows a common feature in aromatic hydrocarbons and also makes it a bridge to organic and hydrogen-rich superconductors.