KDM5B promotes metastasis and epithelial-mesenchymal transition via Wnt/ß-catenin pathway in squamous cell carcinoma of the head and neck.

Metastasis determines clinical management decision and restricts the therapeutic efficiency in patients with squamous cell carcinoma of the head and neck (SCCHN). Epigenetic factor KDM5B serves as an oncogene in multiple cancers. However, its role in SCCHN metastasis remains unclear. Our previous study showed that KDM5B is significantly elevated in SCCHN tissue and is positively correlated with metastasis and recurrence. KDM5B overexpression predicted a poor prognosis in both disease-free survival and overall survival, which served as an independent prognostic factor in SCCHN patients. This study further investigates the exact impact of KDM5B in metastasis of SCCHN. We found that KDM5B knockdown significantly inhibits the migration and invasion of SCCHN cells both in vitro and in vivo. On the contrary, forced expression of KDM5B leads to enhanced migration and invasion, accompanied by canonical alterations of epithelial-mesenchymal transition (EMT). Mechanism investigations demonstrated that KDM5B activates Wnt/ß-catenin pathway, and inhibition of Wnt/ß-catenin pathway via a small molecule inhibitor iCRT-14 partially reverses the enhanced migratory and invasive ability caused by KDM5B in SCCHN cells. Together, our data indicate that KDM5B promotes EMT and metastasis via Wnt/ß-catenin pathway in SCCHN, suggesting that KDM5B may be a potential therapeutic target and prognosis biomarker in SCCHN.

An Fc Binding Peptide-Based Facile and Versatile Build Platform for Multispecific Antibodies.

Multispecific antibodies (MsAbs) maintain the specificity of versatile antibodies while simultaneously addressing different epitopes for a cumulative, collaborative effect. They could be an alternative treatment to chimeric antigen receptor-T cell therapy by helping to redirect T cells to tumors in vivo. However, one major limitation of their development is their relatively complex production process, which involves performance of a massive screen with low yield, inconsistent quality, and nonnegligible impurities. Here, a poly(l-glutamic acid)-conjugated multiple Fc binding peptide-based synthesis nanoplatform was proposed, in which MsAbs were constructed by mixing the desired monoclonal antibodies (mAbs) with polymeric Fc binding peptides in aqueous solution without purification. To determine its efficacy, a dual immune checkpoint-based PD1/OX40 bispecific antibody and PDL1/CD3e/4-1BB trispecific antibody-based T cell engager were generated to trigger antitumor CD8+ T responses in mice, showing superior tumor suppression over free mixed mAbs. In this study, a facile, versatile build platform for MsAbs was established.

Bicarbonate transporter SLC4A7 promotes EMT and metastasis of HNSCC by activating the PI3K/AKT/mTOR signaling pathway.

Head and neck squamous cell carcinoma (HNSCC) is the sixth most common cancer worldwide. Currently, therapeutic modalities such as surgery, chemotherapy, radiotherapy, and immunotherapy are being used to treat HNSCC. However, the treatment outcomes of most patients are dismal because they are already in middle or advanced stage by the time of diagnosis and poorly responsive to treatments. It is therefore of great interest to clarify mechanisms that contribute to the metastasis of cells to identify possible targets for therapy. In this study, we identified the Na+ -coupled bicarbonate transporter, SLC4A7, play essential roles in the metastasis of HNSCC. Our results showed that the relative expression of SLC4A7 messenger RNA was highly expressed in HNSCCs samples from TCGA, and compared with precancerous cells of human oral mucosa (DOK), SLC4A7 was highly expressed in HNSCC cell lines. In vitro and in vivo experiments showed that dysregulation of SLC4A7 had minor influence on the proliferation of HNSCC but impacted HNSCC's migration and invasion. Meanwhile, SLC4A7 could promote epithelial-mesenchymal transition (EMT) in HNSCC. RNA-seq, KEGG pathway enrichment analysis and Western blot further revealed that downregulation of SLC4A7 in HNSCC cells inhibited the PI3K/AKT pathway. These findings were further validated via rescue experiments using a small molecule inhibitor of PI3K/mTOR (GDC-0980). Our findings suggest that SLC4A7 promotes EMT and metastasis of HNSCC through the PI3K/AKT/mTOR signaling pathway, which may be a valuable predictive biomarker and potential therapeutic target in HNSCC.

The association between blood pressure control and long-term cardiovascular outcomes in Hypertension coexistent with obstructive sleep apnea.

PURPOSE: The goal of blood pressure (BP) control will be lower when hypertensive patients have comorbidities that can affect the risk of cardiovascular diseases. But, the goal of BP control for hypertensive patients coexistent with obstructive sleep apnea (OSA) is not discussed, which is a special population at high risk of cardiovascular diseases. PATIENTS AND METHODS: Using data from a retrospective study(Urumqi Research on Sleep Apnea and Hypertension (UROSAH) study, we enrolled 3267 participants who were diagnosed with hypertension and performed polysomnography during 2011-2013 to explore the association between BP control and long-term major adverse cardiovascular and cerebrovascular event (MACCE). Outcomes of interest was the levels of BP control, MACCE, cardiac event and cerebrovascular event. Then we calculated the cumulative incidence of MACCE and performed Cox proportional hazards with stepwise models. RESULTS: 379 of 3267 patients experienced MACCE during a median follow-up of 7.0 years. After full risk adjustment, BP control of 120-139/80-89mmHg was associated with the lowest risk of cerebrovascular event (HR: 0.53, 95%CI:0.35-0.82) rather than MACCE and cardiac event in the total cohort. The association did not change much in patients with OSA. When the SBP and DBP were discussed separately, the SBP control of 120-139mmHg or < 120mmHg was associated with the decreased incidence of MACCE and cerebrovascular event. When DBP control < 80 mm Hg, the risk of cerebrovascular event showed 54% decrease [(HR:0.46, 95%CI: 0.25-0.88)] in patients with hypertension and OSA. CONCLUSION: In this retrospective study, antihypertensive-drug-induced office and home BP control at 120-139/80-89mmHg showed possible beneficial effect on incident MACCE. However, current results need to be verified in future studies.

Body roundness index improves the predictive value of cardiovascular disease risk in hypertensive patients with obstructive sleep apnea: a cohort study.

BACKGROUND: Obesity, especially visceral obesity, plays an important role in the progression of cardiovascular disease (CVD). The body roundness index (BRI) is a new measure of obesity that is considered to reflect visceral obesity more comprehensively than other measures. This study aims to evaluate the relationship between BRI and CVD risk in hypertensive patients with obstructive sleep apnea (OSA) and explore its superiority in predicting CVD. METHODS: The Cox proportional hazards model was used to calculate the hazard ratios (HRs) and 95% confidence intervals (CIs) for incident CVD. The area under the curve (AUC), continuous net reclassification improvement (NRI), and integrated discrimination improvement (IDI) were used to assess which measures of obesity had the best predictive value for CVD risk. RESULTS: During a median follow-up period of 6.8 years, 324 participants suffered a CVD event. After multivariable adjustment, compared with the reference group (the first tertile), the HRs (95% CI) of CVD were 1.25 (95% CI, 0.93-1.70) and 1.74 (95% CI, 1.30-2.33) for subjects in the tertile 2 and tertile 3 groups, respectively. Compared with other measurement indicators, BRI has the highest predictive value for CVD risk [AUC: 0.627, 95% CI: 0.593-0.661]. The addition of the BRI to the fully adjusted multivariate model improved the predictive power for CVD, which was validated in the continuous NRI and the IDI (all P < .05). CONCLUSIONS: BRI was significantly associated with the risk of CVD in hypertensive patients with OSA. Furthermore, BRI may improve CVD risk prediction in hypertensive patients with OSA.

An Amorphous n-Type Conjugated Polymer with an Ultra-Rigid Planar Backbone.

High charge carrier mobility polymer semiconductors are always semi-crystalline. Amorphous conjugated polymers represent another kind of polymer semiconductors with different charge transporting mechanism. Here we report the first near-amorphous n-type conjugated polymer with decent electron mobility, which features a remarkably rigid, straight and planar polymer backbone. The molecular design strategy is to copolymerize two fused-ring building blocks which are both electron-accepting, centrosymmetrical and planar. The polymer is the alternating copolymer of double B←N bridged bipyridine (BNBP) unit and benzobisthiazole (BBTz) unit. It shows a decent electron mobility of 0.34 cm2  V-1 s-1 in organic field-effect transistors. The excellent electron transporting property of the polymer is possibly due to the ultrahigh backbone stiffness, small π-π stacking distance, and high molecular weight.

An n-Type Polythiophene Derivative with Excellent Thermoelectric Performance.

Typical n-type conjugated polymers are based on fused-ring electron-accepting building blocks. Herein, we report a non-fused-ring strategy to design n-type conjugated polymers, i.e. introducing electron-withdrawing imide or cyano groups to each thiophene unit of a non-fused-ring polythiophene backbone. The resulting polymer, n-PT1, shows low LUMO/HOMO energy levels of -3.91 eV/-6.22 eV, high electron mobility of 0.39 cm2  V-1 s-1 and high crystallinity in thin film. After n-doping, n-PT1 exhibits excellent thermoelectric performance with an electrical conductivity of 61.2 S cm-1 and a power factor (PF) of 141.7 µW m-1 K-2 . This PF is the highest value reported so far for n-type conjugated polymers and this is the first time for polythiophene derivatives to be used in n-type organic thermoelectrics. The excellent thermoelectric performance of n-PT1 is due to its superior tolerance to doping. This work indicates that polythiophene derivatives without fused rings are low-cost and high-performance n-type conjugated polymers.

Poor sleep quality is negatively associated with low cognitive performance in general population independent of self-reported sleep disordered breathing.

BACKGROUND: Sleep disordered breathing (SDB) plays a significant role in both sleep quality and cognition and whether it has an impact on the relationship between above two factors remains to be clear. The study aimed to explore the association between sleep quality and cognitive performance in general population by considering influence of sleep disordered breathing (SDB). METHODS: In this cross-sectional study, we enrolled subjects aged ≥ 18 years using a multi-stage random sampling method. Cognitive status was assessed using Mini Mental State Examination (MMSE) questionnaire, sleep quality using Pittsburgh Sleep Quality Index (PSQI) and SDB was assessed using No-SAS scale, respectively. Multi-variable logistic regression was applied to examine the association of sleep quality and cognitive performance. Subgroup analyses were performed in different age groups, and in those with and without SDB. RESULTS: Finally, 30,872 participants aged 47.5 ± 13.8 years with 53.5% women were enrolled, of whom 32.4% had poor sleep quality and 18.6% had low cognitive performance. Compared with good sleepers, subjects with poor sleep quality exhibited significantly higher presence of low cognitive performance (23.7% vs 16.2%, P < 0.001). Poor sleepers revealed 1.26 (95%CI: 1.16,1.36), 1.26 (1.08,1.46) and 1.25 (1.14,1.37) fold odds for low cognitive performance in general population and in subjects with and without self-reported SDB respectively. Stratified by age and SDB, the association was observed in young and middle-aged group without SDB (OR = 1.44, 95%CI: 1.30,1.59) and in the elderly group with SDB (OR = 1.30, 95%CI: 1.07,1.58). CONCLUSIONS: Sleep quality is in a negative association with cognitive performance in general population independent of SDB, implying improvement of sleep disturbances is a potential objective of intervention strategies for cognitive protection at population level.

Arbuscular mycorrhizal fungus facilitates ryegrass (Lolium perenne L.) growth and polychlorinated biphenyls degradation in a soil applied with nanoscale zero-valent iron.

Nanoscale zero-valent iron (nZVI) shows an excellent degradation effect on chlorinated contaminants in soil, but poses a threat to plants in combination with phytoremediation. Arbuscular mycorrhizal (AM) fungus can reduce the phyototoxicity of nZVI, but their combined impacts on polychlorinated biphenyls (PCBs) degradation and plant growth remain unclear. Here, a greenhouse pot experiment was conducted to investigate the influences of nZVI and/or Funneliformis caledonium on soil PCB degradation and ryegrass (Lolium perenne L.) antioxidative responses. The amendment of nZVI significantly reduced not only the total and homolog concentrations of PCBs in the soil, but also the ryegrass biomass as well as soil available P and root P concentrations. Moreover, nZVI significantly decreased leaf superoxide disutase (SOD) activity, while tended to decrease the protein content. In contrast, the additional inoculation of F. caledonium significantly increased leaf SOD activity and protein content, while tended to increase the catalase activity and tended to decrease the malondialdehyde content. The additional inoculation of F. caledonium also significantly increased soil alkaline phosphatase activity, and tended to increase root P concentration, but had no significantly effects on soil available P concentration, the biomass and P acquisition of ryegrass, which could be attributed to the fixation of soil available nutrients by nZVI. Additionally, F. caledonium facilitated PCB degradation in the nZVI-applied soil. Thus, AM fungus can alleviate the nZVI-induced phytotoxicity, showing great application potentials in accompany with nZVI for soil remediation.

Bedside echocardiography for diagnosis of intracardiac cement embolism after percutaneous vertebroplasty: A case report.

This case report is to demonstrate that a female patient had suddenly become unconscious 14 hours after percutaneous vertebroplasty. Bedside echocardiogram showed that the patient had a strong echo in the right heart with a small amount of pericardial effusion. CT showed high density in the distal branches of both pulmonary arteries and a high density in the right heart. With the help of that, the doctor made the diagnosis of intracardiac cement embolism in a very short time. The bone cement in the heart was removed under emergency cardiopulmonary bypass, then the patient was discharged smoothly.

Protective effect of Apelin/APJ system on lipopolysaccharide-related cardiac dysfunction.

At present, the pathogenesis of sepsis-induced myocardial dysfunction (SIMD) is not completely clear and effective treatment measures are lacking. Apelin is an endogenous ligand of the angiotensin like G protein coupled receptor APJ and a cardiovascular peptide with multiple functions. Our aim is to analyze the protective effect and mechanism of Apelin/APJ system on lipopolysaccharide (LPS)-induced myocardial dysfunction. One hour before LPS treatment, apelin-13 or an APJ antagonist [Ala]-apelin-13 (F13A) was given for pre-intervention to observe the effect of apelin-13 on cardiac ultrasound, pathological changes and inflammatory factors in LPS-treated mice. Another part of the mice was treated with apelin-13 or apelin-13 combined with F13A one hour after LPS treatment. The results showed that apelin-13 injection significantly reversed the decrease of ejection fraction and the increase of inflammatory factors induced by LPS in mice. Endogenous apelin may have protective effect on SIMD induced by LPS. Exogenous administration of apelin may inhibit LPS-induced inflammation, apoptosis and increase autophagy through TLR4/ERK1/2/NF-κB pathway.

Biodegradable Natural Pectin-Based Flexible Multilevel Resistive Switching Memory for Transient Electronics.

Transient electronics that can physically vanish in solution can offer opportunities to address the ecological challenges for dealing with the rapidly growing electronic waste. As one important component, it is desirable that memory devices combined with the transient feature can also be developed as secrecy information storage systems besides the above advantage. Resistive switching (RS) memory is one of the most promising technologies for next-generation memory. Herein, the biocompatible pectin extracted from natural orange peel is introduced to fabricate RS memory devices (Ag/pectin/indium tin oxides (ITO)), which exhibit excellent RS characteristics, such as forming free characteristic, low operating voltages (≈1.1 V), fast switching speed (<70 ns), long retention time (>104 s), and multilevel RS behaviors. The device performance is not degraded after 104 bending cycles, which will be beneficial for flexible memory applications. Additionally, instead of using acid solution, the Ag/pectin/ITO memory device can be dissolved rapidly in deionized water within 10 min thanks to the good solubility arising from ionization of its carboxylic groups, which shows promising application for green electronics. The present biocompatible memory devices based on natural pectin suggest promising material candidates toward enabling high-density secure information storage systems applications, flexible electronics, and green electronics.

Echocardiographic strain in hypertrophic cardiomyopathy and hypertensive left ventricular hypertrophy.

BACKGROUND: The myocardial structure differs between secondary left ventricular hypertrophy (LVH) and hypertrophic cardiomyopathy (HCM). We investigated left ventricular function of these two types of hypertrophy using multilayer strain analysis with two-dimensional echocardiography. METHODS: Transthoracic echocardiography (Vivid-E9) was performed in 240 patients with preserved left ventricular ejection fraction (LVEF ≥50%) and with either HCM (n = 80, 63 men, age 49.8 ± 14.1 years), hypertensive LVH (n = 80, 63 men, age 51.4 ± 13.3 years) or normal blood pressure and left ventricular structure (n = 80, 63 men, 50.8 ± 12.4 years). Quantitative multilayer longitudinal strain (LS), circumferential strain (CS), and radial strain (RS) were analyzed. The ratio of endo-/epi-myocardial strain was calculated. RESULTS: Longitudinal strain was significantly (P < 0.001) lower in HCM patients than normal controls (15.2 ± 4.2% vs 23.1 ± 2.7%), especially in hypertrophic segments (14.5 ± 4.4% vs 17.2 ± 3.2% in nonhypertrophic segments, P < 0.01). LS was lower in patients with hypertensive LVH, similarly in all left ventricular segments (20.7 ± 3.7%, P < 0.001 vs controls). CS was lower in the mid- and epicardium (P < 0.01), but not endocardium in HCM (P = 0.4), and preserved in all myocardial layers in hypertensive LVH. The endo-/epi-myocardial ratios of both LS and CS were higher in HCM than hypertensive LVH (P < 0.01). RS was higher (P < 0.01) in HCM than hypertensive LVH and controls. Endocardial CS and global RS were correlated with LVEF (r ≥ 0.32, P < 0.01). CONCLUSIONS: Hypertrophic cardiomyopathy patients had marked reductions in LS and CS, whereas patients with hypertensive LVH had less reduction in LS and preserved CS. The increased endo-/epi-myocardial ratios of LS and CS may be useful in differentiating HCM from hypertensive LVH.

Intercropping with sunflower and inoculation with arbuscular mycorrhizal fungi promotes growth of garlic chive in metal-contaminated soil at a WEEE-recycling site.

Heavy metal (HM) pollution in agricultural soils due to the recycling of waste electrical and electronic equipment (WEEE) has become a serious concern, but most farmers cannot afford the economic losses of fallow land during remediation. Thus, it is imperative to produce low-HM crops while remediating the contaminated soils. A 17-week pot experiment was conducted to investigate the growth and HM (Cd, Cu, Pb, Cr, Zn, and Ni) acquisition of garlic chives (Allium tuberosum Rottl. ex Spreng.) intercropped with sunflower (Helianthus annuus L.) and inoculated with (I+M) or without (I-M) the arbuscular mycorrhizal (AM) fungus Funneliformis caledonium on a severely HM-contaminated soil that was collected from a WEEE-recycling site. Compared with the monoculture control, the I-M treatment significantly (P < 0.05) decreased Cd, Cu, Cr, Zn, and Ni concentrations in the shoots of chives through rhizosphere competition and HM (except Cr) transfer from the root to the shoot of chives, and increased the average shoot fresh weight (i.e., yield) of chives by 794% by alleviating HM toxicity. Compared with the I-M treatment, the I+M treatment significantly increased soil phosphatase activity as well as root mycorrhizal colonization of both sunflower and chives. The I+M treatment had no effect on the tissue P concentration of sunflower but elevated the average dry biomass (shoot plus root) and P acquisition level of sunflower by 179% and 121%, respectively. In addition, the I+M treatment significantly increased the P concentration in the root rather than in the shoot of chives and significantly increased the level of P acquisition by chives, increasing the average yield of chives by 229%. Simultaneously, the I+M treatment significantly increased the level of HM (except Cd) acquisition by sunflower, enhancing the rhizosphere competition by sunflower over chives, and further reducing the transfer of all six HMs from root to shoot in the chives, and inducing significant decreases in chive shoot HM concentrations compared with the monoculture control. Furthermore, the I+M treatment decreased the average total concentrations and increased the average DTPA-extractable concentrations of soil HMs. The results demonstrate the multifunctional role of AM fungi in the intercropping system for both vegetable production and phytoremediation on HM-contaminated soils.

Cross-Linked Pectin Nanofibers with Enhanced Cell Adhesion.

Polysaccharides display poor cell adhesion due to the lack of cell binding domains. This severely limits their applications in regenerative medicine. This study reports novel cross-linked pectin nanofibers with dramatically enhanced cell adhesion. The nanofibers are prepared by at first oxidizing pectin with periodate to generate aldehyde groups and then cross-linking the nanofibers with adipic acid dihydrazide to covalently connect pectin macromolecular chains with adipic acid dihydrazone linkers. The linkers may act as cell binding domains. Compared with traditional Ca2+-cross-linked pectin nanofibers, the pectin nanofibers with high oxidation/cross-linking degree exhibit much enhanced cell adhesion capability. Moreover, the cross-linked pectin nanofibers exhibit excellent mechanical strength (with Young's modulus ∼10 MPa) and much enhanced body degradability (degrade completely in 3 weeks or longer time). The combination of excellent cell adhesion capability, mechanical strength, and body degradability suggests that the cross-linked pectin nanofibers are promising candidates for in vivo applications such as tissue engineering and wound healing. This cross-linking strategy may also be used to improve the cell adhesion capability of other polysaccharide materials.

Size-Tunable Low Molecular Weight Pectin-Based Electrospun Nanofibers Blended with Low Content of Poly(ethylene oxide).

Pectin, a natural plant polysaccharide, holds great potential for biomedicine. Developing low molecular weight (Mw) pectin-based nanofibers is desirable for biomedical applications in which fast degradation and elimination of polymer from the body are required. Here, we report the first work on fabricating low Mw pectin-based nanofibers through electrospinning, among which the content of carrier polymer, poly(ethylene oxide) (PEO), can be minimized to 10%. Surfactant (Triton X-100), high polymer concentration and cosolvent were essential to electrospin bead-free nanofibers at low PEO content. The size of pectin nanofibers was dependent on polymer concentration and cosolvent. The presence of cosolvent inhibited the crystallization of PEO, but enhanced the crystallization of pectin. Meanwhile, glycerol as cosolvent could lead to phase separation of polymers. This work provides a new prospective for the fabrication of low Mw pectin nanofibers suitable for in vivo applications with the demand of fast degradation.

IDENTIFICATION OF PROTEASOME ALPHA6 SUBUNIT ASSOCIATED WITH DELTAMETHRIN RESISTANCE IN Drosophila melanogaster Kc CELLS.

Differential expression of the proteasome alpha6 (prosalpha6) was previously reported between Plutella xylostella strains that are resistant or susceptible to the pesticide deltamethrin (DM). This finding indicated that the prosalpha6 may be involved in DM resistance. In this article, qPCR analysis revealed that the prosalpha6 was also significantly upregulated in Drosophila Kc cells treated with DM. To better understand the contribution of prosalpha6 in DM resistance, RNA interference, heterologous expression, and a proteasome inhibitor (MG-132) were used. MG-132 was used to suppress proteasomal activity, and the dsRNA was designed to block the function of prosalpha6. The results indicated that both MG-132 and prosalpha6 knockdown decreased the cellular viability following DM treatment. Prosalpha6 was cloned and transfected into Drosophila Kc cells. The result showed that overexpression of prosalpha6 in Drosophila Kc cells conferred some protection against DM. Taken together, our results indicate that prosalpha6 is involved in Drosophila cells DM resistance.

The clinical value of dynamic contrast-enhanced MRI in differential diagnosis of malignant and benign ovarian lesions.

Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) is widely used in preoperative diagnosis of various tumors. We investigated the clinical value of DCE-MRI in differential diagnosis of malignant and benign ovarian lesions. The study involved 48 subjects with surgical pathology-confirmed ovarian tumors with solid components. Early dynamic phase enhancement performances of the ovarian lesions in patients were assessed, including the enhancement pattern, time-signal intensity curve (TIC), signal intensity rate at the initial 60 s (SI60), time to peak within 200 s (TTP200), and slope ratio. There were significant differences in enhancement patterns between benign and malignant ovarian tumors (P < .05). A total of 30 malignant tumors (30/31) displayed type I TIC, 8 benign tumors (8/13) showed type III TIC, and significant differences were found in TIC type between malignant and benign ovarian lesions (P < 0.01). Benign ovarian tumors showed lower SI60 (%) and slope ratio, as well as significantly prolonged TTP20, compared to malignant ovarian tumors (all P < 0.01). The microvessel count (MVC) of malignant tumors was significantly higher than that of benign tumors (P < 0.05). Receiver operating characteristic (ROC) curve analyses revealed that DCE-MRI provided an optimal diagnostic performance with threshold values of SI60 at 83.40 %, TTP200 at 77.65 s, and slope ratio at 4.12. These findings revealed that DCE-MRI provides critical information required for differential diagnosis of malignant and benign ovarian lesions.

PROTEOMIC ANALYSIS OF UBIQUITINATED PROTEINS FROM DELTAMETHRIN-RESISTANT AND SUSCEPTIBLE STRAINS OF THE DIAMONDBACK MOTH, Plutella Xylostella L.

Ubiquitin, a small protein consisting of 76 amino acids, acts in protein degradation, DNA repair, signal transduction, transcriptional regulation, and receptor control through endocytosis. Using proteomics, we compared the differentially ubiquitinated proteins between a deltamethrin-resistant (DR) strain and a deltamethrin-sensitive (DS) strain in third-instar larvae of the diamondback moth. We used polyubiquitin affinity beads to enrich ubiquitinated proteins and then performed one-dimensional SDS-PAGE separation and mass spectrometric identification. In the DR strain, We found 17 proteins that were upregulated (relative to the DS strain), including carbonic anhydrase family members, ADP ribosylation factor 102F CG11027-PA, protein kinase 61C, phospholipase A2 , dihydrolipoamide dehydrogenase, tyrosine hydroxylase, and heat shock proteins, and five proteins that were downregulated in the DS strain, including carboxylesterase and DNA cytosine-5 methyltransferase. These results were also verified by qPCR. The differentially ubiquitinated proteins/enzymes were mainly responsible for protein binding, catalytic activity, and molecular transducer activity. These results improve our understanding of the relationship between protein ubiquitination and the deltamethrin stress response.

Dosage and exposure time effects of two micro(nono)plastics on arbuscular mycorrhizal fungal diversity in two farmland soils planted with pepper (Capsicum annuum L.).

As emerging environmental pollutants, micro(nano)plastics (MPs) like polyethylene terephthalate (PET) and low-density polyethylene (LDPE) have adverse effects on terrestrial biota and ecosystem function. However, the performance and roles of soil arbuscular mycorrhizal (AM) fungi in MPs-contaminated vegetable fields are poorly understood. Thus, a 120-day pot experiment was conducted to test the impacts of two input levels of either PET (~13 µm) or LDPE (~500 nm) on AM fungal diversity and pepper (Capsicum annuum L.) growth in two farmland soils collected from Nanjing (NJ) and Chongqing (CQ), respectively. In the vast majority of cases, 1 % rather than 0.1 % of both MPs greatly decreased the observed richness, Shannon and Simpson's indices, and Pielou's evenness of AM fungi, and decreased mycorrhizal colonization, root and shoot biomasses, fruit yield, and leaf superoxide dismutase, peroxidase, and catalase activities of pepper, while increased leaf malondialdehyde content. From day 40 to 120, the inhibition of either diversity or vitality of AM fungi by 1 % and 0.1 % of MPs gradually increased and weakened, respectively. Compared with PET, LDPE with substantially smaller particle size was more toxic to mycorrhization at day 40, but no longer at day 120. Almost all plant parameters significantly correlated to mycorrhizal colonization, which significantly correlated to both Shannon and Simpson's indices of AM fungi, and soil pH, available P and K concentrations, and alkaline phosphatase activity. All diversity indices of AM fungi clearly negatively correlated to soil pH from 4.4 to 5.6 for the NJ soil and from 5.3 to 6.5 for the CQ soil, and also positively to mineral N and negatively to available P concentrations for the NJ and CQ soils, respectively. Thus, the study emphasized that high input of MPs significantly inhibited soil AM fungal diversity and vitality and thereby vegetable growth via changing soil pH and major nutrient availability.