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To validate a response surface model for the inhibition of somatic motor response at corrected body weight (CBW) doses of remifentanil plus propofol in elderly patients and to analyze the dose-effect relationship and optimal dosing range for total intravenous anesthesia (TIVA) induction in painless gastroscopy.We designed a prospective, open-ended, randomized, parallel group study. A total of 300 elderly patients undergoing painless gastroscopy were randomized to receive remifentanil (0-0.5 μg/kg) and propofol (0.8-2.2 mg/kg) dosing based on CBW. Gastroscopy was performed at the drug's peak effect time. The somatic motor response to gastroscopic stimulation and the adverse reactions at different points were recorded. The somatic motor response was used as the basic element in the subsequent RSM analysis. Model parameters and 95% confidence intervals were fitted by MATLAB software.The CBW doses of remifentanil and propofol showed synergistic inhibitory effects on motor response to noxious stimulation and attenuated adverse reactions. The 50% effective doses of remifentanil and propofol for inhibiting the motor response were 1.754 μg/kg and 2.048 mg/kg, respectively.Remifentanil or propofol alone could not inhibit the somatic motor response at weight-adjusted doses among elderly patients. A combination of remifentanil and propofol showed a synergistic interaction in suppressing the motor response and adverse reactions in elderly patients. Preinjection of remifentanil could reduce the needed dose of propofol.

Polysaccharides are important pharmacologically active substances found in the perennial orchid Dendrobium huoshanense. In the present study, we sought to determine whether antioxidant and anti-inflammatory mechanisms were involved in Dendrobium huoshanense polysaccharides (DHPs)-mediated protection from D-galactose-induced intestine injury in an aging rat model. The effects of DHPs on ileal antioxidant capacity, mucosal barrier integrity and the inflammatory response were investigated in D-galactose-treated rats. The results showed that DHP administration largely attenuated the D-galactose-induced malondialdehyde (MDA), interleukin (IL)-6, tumor necrosis factor (TNF)-α, IL-4, IL-10, Toll-like receptor four and NF-κBp65 content increases and also markedly renewed the total antioxidant capacity and the claudin and occludin contents of ileal tissues from the D-galactose-treated rats. We also found that DHP more markedly affected the IL-6 and TNF-α levels than it did the IL-4 and IL-10 levels in the ileal tissues from the D-galactose-treated rats. These results suggest that DHPs can protect the rat ileum from D-galactose-induced injury by attenuating lipid peroxidation, improving antioxidant capacity and mucosal barrier integrity, correcting imbalanced inflammatory cytokine networks and suppressing the inflammatory response. The novel insights into the mechanism involved in DHPs protection of ileal health in our D-galactose-induced aging model rat advances current understanding of the aging process.

A single insulin receptor (InR) gene has been identified and extensively studied in model species ranging from nematodes to mice. However, most insects possess additional copies of InR, yet the functional significance, if any, of alternate InRs is unknown. Here, we used the wing-dimorphic brown planthopper (BPH) as a model system to query the role of a second InR copy in insects. NlInR2 resembled the BPH InR homologue (NlInR1) in terms of nymph development and reproduction, but revealed distinct regulatory roles in fuel metabolism, lifespan, and starvation tolerance. Unlike a lethal phenotype derived from NlInR1 null, homozygous NlInR2 null mutants were viable and accelerated DNA replication and cell proliferation in wing cells, thus redirecting short-winged–destined BPHs to develop into long-winged morphs. Additionally, the proper expression of NlInR2 was needed to maintain symmetric vein patterning in wings. Our findings provide the first direct evidence for the regulatory complexity of the two InR paralogues in insects, implying the functionally independent evolution of multiple InRs in invertebrates., Author summary The highly conserved insulin/insulin-like growth factor signaling pathway plays a pivotal role in growth, development, and various physiological processes across a wide phylogeny of organisms. Unlike a single InR in the model species such as the fruit fly Drosophila melanogaster and the nematode Caenorhabditis elegans, most insect lineages have two or even three InR copies. However, the function of the alternative InRs remains elusive. Here, we created a homozygous mutation for a second insulin receptor (InR2) in the wing-dimorphic brown planthopper (BPH), Nilaparvata lugens, using the clustered regularly interspaced palindromic repeats/CRISPR-associated (CRISPR/Cas9) system. Our findings revealed that InR2 possesses functions distinct from the BPH InR homologue (NlInR1), indicating that multiple InR paralogues may have evolved independently and may have functionally diversified in ways more complex than previously expected in invertebrates.

Background A plethora of prognostic biomarkers for esophageal squamous cell carcinoma (ESCC) that have hitherto been reported are challenged with low reproducibility due to high molecular heterogeneity of ESCC. The purpose of this study was to identify the optimal biomarkers for ESCC using machine learning algorithms. Methods Biomarkers related to clinical survival, recurrence or therapeutic response of patients with ESCC were determined through literature database searching. Forty-eight biomarkers linked to recurrence or prognosis of ESCC were used to construct a molecular interaction network based on NetBox and then to identify the functional modules. Publicably available mRNA transcriptome data of ESCC downloaded from Gene Expression Omnibus (GEO) and The Cancer Genome Atlas (TCGA) datasets included GSE53625 and TCGA-ESCC. Five machine learning algorithms, including logical regression (LR), support vector machine (SVM), artificial neural network (ANN), random forest (RF) and XGBoost, were used to develop classifiers for prognostic classification for feature selection. The area under ROC curve (AUC) was used to evaluate the performance of the prognostic classifiers. The importances of identified molecules were ranked by their occurrence frequencies in the prognostic classifiers. Kaplan-Meier survival analysis and log-rank test were performed to determine the statistical significance of overall survival. Results A total of 48 clinically proven molecules associated with ESCC progression were used to construct a molecular interaction network with 3 functional modules comprising 17 component molecules. The 131,071 prognostic classifiers using these 17 molecules were built for each machine learning algorithm. Using the occurrence frequencies in the prognostic classifiers with AUCs greater than the mean value of all 131,071 AUCs to rank importances of these 17 molecules, stratifin encoded by SFN was identified as the optimal prognostic biomarker for ESCC, whose performance was further validated in another 2 independent cohorts. Conclusion The occurrence frequencies across various feature selection approaches reflect the degree of clinical importance and stratifin is an optimal prognostic biomarker for ESCC.

Highly emissive phenanthrene-fused boron–dipyrromethene (PBDP) dyes have been spectroscopically characterized in a series of solvents. The influence of different substituents (−H, −I, −CN, −DMA or a 15C5-crown ether) in the para-position of a phenyl ring attached to the meso-position of the BODIPY core is discussed. This family of dyes has an intense emission at λ ≥ 630 nm, with fluorescence quantum yields between 0.7 and 1.0 in all solvents studied, except in the case of the dimethylamino-substituted derivative, PBDP-DMA, which undergoes excited-state intramolecular charge transfer (CT), leading to broadband dual fluorescence in highly polar solvents. Introduction of a weaker electron donor such as a benzocrown to the meso-position is not able to trigger a second (charge or electron transfer) process and, interestingly, heavy atom (iodine, PBDP-I derivative) substitution at that moiety does also not have a relevant influence on the photophysics, i.e., enhanced intersystem crossing was not observed. Electrochemical studies of PBDP-DMA complement the data reported and stress the fact that the decrease in fluorescence of PBDP-DMA in highly polar solvents is due to an excited-state CT process rather than to a photoinduced electron transfer (PET).

The Dayingezhuang gold deposit in the Jiaodong district, eastern margin of the North China Craton is hosted in Mesozoic granitic rocks and consists of quartz-sulfide veins/veinlets and sulfide disseminations in alteration envelopes. Previous studies mainly focused on the geochronology, sources of ore-forming fluids and metals to investigate the ore genesis. However, enrichment mechanism of Au and other associated trace metals remain unclear. In this study, we present detailed textures and in-situ LA-ICP-MS trace-element compositions of different generations of pyrite, as well as EMP analysis of Au-bearing minerals to discuss the occurrence and enrichment mechanism of Au at this deposit. Three generations of pyrite (Py1, Py2 and Py3) formed during three hydrothermal ore stages (I, II, and III) at Dayingezhuang. Py1 occurs as disseminations in sericitic alteration assemblages and is characterized by low Au (mean 0.15 ppm), Ag, As and Te contents. The time-resolved depth-concentration profiles indicate that Au in Py1 mainly occurs as nanoparticles and/or micron-sized inclusions. Py2 can be further divided into the early undeformed Py2a and later Py2b, which is the product of deformed Py2a with different degrees of brittle to plastic deformation and recrystallization. Py2a in pyrite-siderite-quartz veins is relatively enriched in invisible Au (mean 0.41 ppm), Ag, As, and Te compared to Py1, and contains numerous micron-sized Au inclusions. In contrast, Py2b contains lesser invisible Au (0.21 ppm) and host abundant gold minerals along the grain boundaries and microfractures. Py3 in polymetallic sulfide veins has little Au. As a whole, Au in pyrite is positively correlated with Ag and Te, which is consistent with the results of EMP analysis showing the occurrence of Au as electrum, native gold and minor petzite in pyrite. Such evidences show that the deformation and recrystallization of auriferous Py2a potentially caused local remobilization of Au (mainly as micron-sized inclusion Au) via solid-state ductile flow and subsequent reconcentration of Au in microfractures of Py2b. The pyrite deformation and Au remobilization events were suggested to be related to the continuous reactivation of the regional Zhaoping Fault contemporaneous with gold mineralization. Our study highlights the importance of remobilization and reconcentration of Au triggered by syn-ore tectonic activities at Dayingezhuang and possibly other Au deposits in the Jiaodong district.

To discuss the molecular mechanism of immunoenhancing activities of Hyriopsis cumingii polysaccharides (HCPS), influences of HCPS on mice immunosignaling molecules (IL-2, IL-10, IFN-γ, NO, cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP)) and T lymphocyte differentiation (to CD4+ and CD8+ T cells) were evaluated by cell model in vitro and/or cyclophosphamide-induced immunosuppression animal model in vivo. Results showed that gastric gavage of crude HCPS could promote the production of IL-2, IFN-γ, inducible nitric oxide synthase (iNOS), cGMP, CD4 and CD8 in a dose-dependent manner. While, crude HCPS by gastric gavage exhibited suppressive effects on the production of IL-10 and cAMP in a dose-dependent manner. Crude HCPS and its purified fractions (HCPS-1, HCPS-2 and HCPS-3) could strengthen peritoneal macrophage expressing iNOS in vitro in a dose-dependent manner. HCPS-stimulated immunostrengthening functions was mediated, at least in part, by immunosignaling molecul...

At present, most of the drugs have little effect on the pathological process of rheumatoid arthritis (RA). Analgesia is an important measure in the treatment of RA and is also one of the criteria to determine the therapeutic effects of the disease. Some studies have found that crocin, a kind of Chinese medicine, can effectively alleviate pain sensitization in pain model rats, but the mechanism is not clear. Emerging evidence indicates that crocin may inhibit the metastasis of lung and liver cancer cells from the breast by inhibiting Wnt/β-catenin and the Wnt signaling pathway is closely related to RA. Wnt5a belongs to the Wnt protein family and was previously thought to be involved only in nonclassical Wnt signaling pathways. Recent studies have shown that Wnt5a has both stimulatory and inhibitory effects on the classical Wnt signaling pathway, and so, Wnt5a has attracted increasing attention. This study demonstrated that crocin significantly increased the mechanical thresholds of adjuvant-induced arthritis (AIA) rats, suggesting that crocin can alleviate neuropathic pain. Crocin significantly decreased the levels of pain-related factors and glial activation. Foxy5, activator of Wnt5a, inhibited the above effects of crocin in AIA rats. In addition, intrathecal injection of a Wnt5a inhibitor significantly decreased hyperalgesia in AIA rats. This research shows that crocin may alleviate neuropathic pain in AIA rats by inhibiting the expression of pain-related molecules through the Wnt5a/β-catenin pathway, elucidating the mechanism by which crocin relieves neuropathic pain and provides a new way of thinking for the treatment of AIA pain.

Wing polymorphism is an evolutionary feature found in a wide variety of insects, which offers a model system for studying the evolutionary significance of dispersal. In the wing-dimorphic planthopper Nilaparvata lugens, the insulin/insulin-like growth factor signaling (IIS) pathway acts as a ‘master signal’ that directs the development of either long-winged (LW) or short-winged (SW) morphs via regulation of the activity of Forkhead transcription factor subgroup O (NlFoxO). However, downstream effectors of the IIS–FoxO signaling cascade that mediate alternative wing morphs are unclear. Here we found that vestigial (Nlvg), a key wing-patterning gene, is selectively and temporally regulated by the IIS–FoxO signaling cascade during the wing-morph decision stage (fifth-instar stage). RNA interference (RNAi)-mediated silencing of Nlfoxo increase Nlvg expression in the fifth-instar stage (the last nymphal stage), thereby inducing LW development. Conversely, silencing of Nlvg can antagonize the effects of IIS activity on LW development, redirecting wing commitment from LW to the morph with intermediate wing size. In vitro and in vivo binding assays indicated that NlFoxO protein may suppress Nlvg expression by directly binding to the first intron region of the Nlvg locus. Our findings provide a first glimpse of the link connecting the IIS pathway to the wing-patterning network on the developmental plasticity of wings in insects, and help us understanding how phenotypic diversity is generated by the modification of a common set of pattern elements., Author summary Many insects are capable of developing into either long-winged or short-winged adults, but the underlying molecular basis remains largely unknown. Pioneer studies showed that the insulin/insulin-like growth factor signaling pathway acts as a ‘master signal’ that directs wing buds to develop into long or short wings in the wing-dimorphic planthopper, Nilaparvata lugens. However, downstream effectors mediating the IIS pathway effects are unknown. Our findings highlight that vestigial, a key wing-patterning gene, is a main downstream effector that mediates the IIS activity on the development of alternative wing morphs during the wing-morph decision stage. The molecular mechanism of wing formation, including the function of vestigial, has been studied in great depth in the model insect Drosophila melanogaster. Our data provide a first glimpse of the link connecting the IIS pathway to the wing-patterning network in regulating developmental plasticity of wings in insects.

The homeotic complex (Hox) gene Ultrabithorax (Ubx) plays pivotal roles in modifying specific morphological differences among the second (T2), the third thoracic (T3), and the first abdomen (A1) segment in several insects. Whether Ubx regulates wing dimorphism and other morphological traits in the delphacid family (order Hemiptera) remains elusive. In this study, we cloned a full-length Ubx ortholog (NlUbx) from the wing-dimorphic planthopper Nilaparvata lugens, and identified two NlUbx isoforms. RNA-interference (RNAi)-mediated silencing of NlUbx in short-winged BPH nymphs significantly induced the development of wing-like appendages from T3 wingbuds, and this effect is likely mediated by the insulin/insulin-like signaling pathway. RNAi knockdown of NlUbx in long-winged BPH nymphs led to a transformation from hindwings to forewings. Additionally, silencing of NlUbx not only dramatically changed the T3 morphology, but also led to jumping defect of T3 legs. First-instar nymphs derived from parental RNAi had an additional leg-like appendages on A1. These results suggest that Ubx plays a role in determining some morphological traits in delphacid planthoppers, and thus help in understanding evolution of morphological characteristics in arthropods.

Histone acetylation is a specific type of chromatin modification that serves as a key regulatory mechanism for many cellular processes in mammals. However, little is known about its biological function in invertebrates. Here, we identified 12 members of histone deacetylases (NlHDACs) in the brown planthopper (BPH), Nilaparvata lugens . RNAi-mediated silencing assay showed that NlHdac1 , NlHdac3 and NlHdac4 played critical roles in female fertility via regulating ovary maturation or ovipositor development. Silencing of NlHdac1 substantially increased acetylation level of histones H3 and H4 in ovaries, indicating NlHDAC1 is the main histone deacetylase in ovaries of BPH. RNA sequencing (RNA-seq) analysis showed that knockdown of NlHdac1 impaired ovary development via multiple signalling pathways including the TOR pathway. Acoustic recording showed that males with NlHdac1 knockdown failed to make courtship songs, and thus were unacceptable to wild-type females, resulting in unfertilized eggs. Competition mating assay showed that wild-type females overwhelmingly preferred to mate with control males over NlHdac1 -knockdown males. These findings improve our understanding of reproductive strategies controlled by HDACs in insects and provide a potential target for pest control.

Rotary drying process modeling is a complex procedure due to the difficulties in measurement and estimation of kinetic model parameters. To solve the problem, a hybrid modeling method with online compensation is proposed in the present study. A mathematical model is built to describe the axial characteristics of rotary drying process. The drying rate which is the key parameter in the model is estimated by using a SVR-based fuzzy modeling approach, which can automatically extract fuzzy IF-THEN rules from support vectors. Laboratory experiments are conducted to obtain the drying rate sample data for the modeling purpose. In order to reduce the modeling errors for an industrial rotary dryer and improve the hybrid model prediction accuracy, an online matching coefficient is introduced, and a method based on improved online SVR is then applied for modeling error compensation. The experiment dada based modeling results have verified the effectiveness and demonstrated the accuracy and adaptability of the proposed hybrid modeling method.

Wing polyphenism is an evolutionarily successful feature found in a wide range of insects. Long-winged morphs can fly, which allows them to escape adverse habitats and track changing resources, whereas short-winged morphs are flightless, but usually possess higher fecundity than the winged morphs. Studies on aphids, crickets and planthoppers have revealed that alternative wing morphs develop in response to various environmental cues, and that the response to these cues may be mediated by developmental hormones, although research in this area has yielded equivocal and conflicting results about exactly which hormones are involved. As it stands, the molecular mechanism underlying wing morph determination in insects has remained elusive. Here we show that two insulin receptors in the migratory brown planthopper Nilaparvata lugens, InR1 and InR2, have opposing roles in controlling long wing versus short wing development by regulating the activity of the forkhead transcription factor Foxo. InR1, acting via the phosphatidylinositol-3-OH kinase (PI(3)K)-protein kinase B (Akt) signalling cascade, leads to the long-winged morph if active and the short-winged morph if inactive. InR2, by contrast, functions as a negative regulator of the InR1-PI(3)K-Akt pathway: suppression of InR2 results in development of the long-winged morph. The brain-secreted ligand Ilp3 triggers development of long-winged morphs. Our findings provide the first evidence of a molecular basis for the regulation of wing polyphenism in insects, and they are also the first demonstration--to our knowledge--of binary control over alternative developmental outcomes, and thus deepen our understanding of the development and evolution of phenotypic plasticity.

Raltitrexed is a specific inhibitor of thymidylate synthase (TS), which has been considered as a potential chemotherapeutic agent for the treatment of advanced gastric cancer. In the present study, the apoptosis mechanisms of raltitrexed in SGC7901 human gastric cancer cells were investigated. The cytotoxic activity of raltitrexed on SGC7901 cells was determined by cell counting kit-8 (CCK-8) assay. The CCK‑8 assay indicated that raltitrexed inhibits SGC7901 cell growth in a dose- and time-dependent manner. The morphological changes were observed by fluorescent microscopy, and characteristic morphological changes, including nuclear shrinkage and apoptotic bodies, were observed following Hoechst 33258 staining. The effects on apoptosis, cell cycle, mitochondrial transmembrane potential and reactive oxygen species (ROS) were measured by flow cytometry. The analysis revealed that raltitrexed exerted a growth inhibitory effect by inducing time-dependent apoptosis and cell-cycle arrest at the G0/G1 phase. In addition, a compromised mitochondrial membrane potential and overproduction of ROS demonstrated the involvement of the mitochondrial signaling pathway. Raltitrexed‑induced caspase‑3‑dependent apoptosis was identified using a caspase-3 activity assay and pretreatment with the caspase-3 inhibitor, Ac‑DEVD‑CHO (sequence, Ac-Asp-Glu-Val-Asp-CHO). The activity of caspase-3 was analyzed with a spectrometer. The protein expression levels of Bax, Bcl-2, cytochrome c, cleaved caspase-3 and TS were examined by western blot and the mRNA expression level of TS was detected by quantitative polymerase chain reaction. The analysis revealed that the protein levels of Bax, cytochrome c and cleaved caspase‑3 were significantly increased by raltitrexed, while Bcl-2 expression levels were reduced. Furthermore, raltitrexed increased the expression of the TS protein and mRNA in a time‑dependent manner. These results indicate that raltitrexed induces the apoptosis of SGC7901 cells through the caspase‑3‑dependent mitochondrial signaling pathway and upregulates the expression of the TS protein and mRNA.

The Dahu lodegold deposit is situated in the Xiaoqinling district, hosted in the east-west-trending shear zones, and characterized by auriferous quartz vein-type. Based on the morphology and paragenetic assemblage, three generations of pyrite (termed as first-generation pyrite (Py1), Py2, and Py3) can be classified. The Py2 can be further identified as brittle fractured pyrite (Py2-B) and ductile deformed pyrite (Py2-D). The different generations of pyrites feature distinct contents and distribution patterns of Au and other trace elements. The coarse-grained, euhedral Py1, disseminating in the early formed pyrite-poor quartz veins, contained negligible to extremely low levels of Au and associated trace elements, probably indicating a slow growth rate from a hydrothermal fluid unsaturated with respect to Fe, S, and Au and other trace elements, such as Cu, Pb, Bi, and Te, during the early orestage. Py2, occurring as laminations in the auriferous quartz veins, consistently contained significant amounts of Au, Bi, and Te, with a strong positive correlation between these elements, probably indicating a rapid growth rate and concentrated precipitation process of pyrite due to a hydrothermal fluid supersaturated with respect to Fe, S, Au, and other trace elements during the pyrite-rich auriferous quartz veining. Py3, which precipitated in the polymetallic sulfide orestage, contained a small amounts of Ag and a dramatically decreased content of Au, Bi, Te, and ratios of Bi/Ag. The results of electron back-scattered diffraction analysis on the Py2 revealed that Py2-B was characterized by predominantly brittle deformation with a limited local plastic deformation by dislocation glide on a simple slide system, whereas the Py2-D displayed a significant crystal plastic deformation through a lattice rotation on two separate 〈1 0 0〉 axes and local dislocation creep. Microscopic petrography and laser ablation inductively coupled plasma mass spectrometry analyses revealed that the brittle fracturing-dominated Py2-B generally displayed homogenous distribution patterns of Au and other trace elements and scarce visible gold grains, whereas the plastically deformed Py2-D generally exhibited an inhomogeneous distribution pattern of trace element and commonly contained fine-grained irregular-shaped visible native gold and other sulfide inclusions in the low-angle boundaries and dislocation sites within Py2-D, possibly suggesting the significant influence of ductile deformation on remobilization and reprecipitation of Au and associated trace elements once locked in Py2. The corrosion of Au-Te-Bi-bearing Py2 by the late polymetallic sulfide assemblage led to a liberation of invisible Au and other trace elements and reprecipitation of visible native gold and other Bi–Pb minerals. The results indicate that brittle deformation exhibited no essential effects on the crystal structure and chemical component of pyrite, whereas the plastic deformation can cause the readjustment of crystal lattices and liberation of impurities (e.g., Au, Te, Bi, and Cu) from the crystal lattices of pyrite. The plastic deformation and dissolution–remobilization of pyrite are the important mechanisms responsible for the visible discrete gold grain formation in auriferous quartz veins. Macroscopically, a preferred constant E–W extending orientation and typical lamination structure of the auriferous quartz veins suggest a channeled fluid flowing along the closed and connected fractures under a syn-mineralization S–N oriented extensional tectonic regime related to the Xiaoqinling metamorphic core complex. Here, we report that the microstructures of ductile deformation and brittle fracturing of the auriferous quartz veins are probably indicative of the continuous shearing activation of the ore-hosting normal fault.

The Haopinggou deposit in the Xiong’ershan district, southern margin of the North China Craton, comprises numerous Au and Ag–Pb–Zn veins hosted in metamorphic rocks of the Late Archean to early Paleoproterozoic Taihua Group. Two stages of mineralization have been recognized: Stage 1 pyrite–quartz veins and Stage 2 Pb–Zn-sulfide veins. Some pyrite–quartz veins are surrounded or cut by Pb–Zn-sulfide veins, others occur as independent veins. Six generations of pyrite have been identified at Haopinggou: Py1 to Py3 in Stage 1 and Py4 to Py6 in Stage 2. Pyrites from Stage 1 are enriched in Au, As, Co, Ni, and Bi, whereas Stage 2 pyrites contain higher Ag, Pb, Zn, Sn, and Sb. Invisible Au mostly occurs as lattice-bound gold in Py2 (up to 92 ppm Au) and Py3 (up to 127 ppm Au) and has a close relationship with As. Native Au grains are also present in Py3 and likely resulted from mobilization and reprecipitation of the invisible Au previously locked in the precursor pyrite. This view is supported by extensive plastic deformation in Stage 1 pyrite as revealed by electron backscatter diffraction analysis. In Stage 2, Ag is mostly present as lattice-bound silver closely associated with Sb in galena (up to 798 ppm Ag). A variety of silver minerals are also present as inclusions within galena or as interstitial grains. These silver minerals were likely formed via Ag–Cu exchange reaction between tetrahedrite and galena or represent exsolution from galena due to a temperature decrease. Pb isotopic compositions differ remarkably between Stage 1 and Stage 2 sulfides, indicating different sources of lead. Pb in Stage 2 Pb–Zn-sulfide veins is consistent with the Haopinggou porphyry close to the veins. The field, textural, compositional, and lead isotopic data led us to conclude that the early gold-bearing pyrite–quartz veins and late silver-bearing Pb–Zn-sulfide veins likely formed from distinct fluid systems related to discrete mineralization events. Our study suggests that Au and Ag–Pb–Zn veins hosted in the same metamorphic terrains may not be genetically related to each other.

Wing polymorphism contributes significantly to the success of a wide variety of insects. However, its underlying molecular mechanism is less well understood. The migratory planthopper (BPH), Nilaparvata lugens , is one of the most extensively studied insects for wing polymorphism, due to its natural features of short- and long-winged morphs. Using the BPH as an example, we first surveyed the environmental cues that possibly influence wing developmental plasticity. Second, we explained the molecular basis by which two insulin receptors (InR1 and InR2) act as switches to determine alternative wing morphs in the BPH. This finding provides an additional layer of regulatory mechanism underlying wing polymorphism in insects in addition to juvenile hormones. Further, based on a discrete domain structure between InR1 and InR2 across insect species, we discussed the potential roles by which they might contribute to insect polymorphism. Last, we concluded with future directions of disentangling the insulin signalling pathway in the BPH, which serves as an ideal model for studying wing developmental plasticity in insects. This article is part of the themed issue ‘Evo-devo in the genomics era, and the origins of morphological diversity’.