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Flexibility and variations in morphological and physiological traits are the key for insect herbivores to adapt to environments. The cotton–melon aphid Aphis gossypii Glover is a polyphagous insect which populations exhibit host specialization. Feeding experience on specific host plants converted host specialization in this aphid. However, adaptive changes of this aphids during the host conversion are still unclear. Here, we examined variations in body length, leg segments, and host preference of the cotton-specialized and cucurbit-specialized aphids, A. gossypii, induced by novel host plants. We found that on the original host plants, body, femur, tibia, and tarsus of the cucurbit-specialized aphids were significantly longer than these of the cotton-specialized aphids. However, feeding on zucchini or cowpea resulted in the short body and leg segments in the cucurbit-specialized aphids, whereas led to the long body and leg segments or no changes in the cotton-specialized aphids, and consequently, the tarsus lengths became equal between the cotton- and cucurbit-specialized aphids. Interestingly, the change trends of the relative lengths of leg segments to body length with the increase of reared generation on zucchini were almost different between the cucurbit-specialized and cotton-specialized aphids, especially the relative length of tarsus, but on cowpea, the trends were similar. Meanwhile, feeding on zucchini altered host preference of the cotton-specialized aphids, but not of the cucurbit-specialized aphids. Novel host plants induce adaptive changes in leg segments and host preference of aphids, suggesting the conversion of host specialization.

Background Gastric cancer (GC) remains an important cancer worldwide. Further understanding of the molecular mechanisms of gastric carcinogenesis will enhance the diagnosis and treatment of GC. Methods The expression of DLEU2 and ETS2 was analyzed in several GC cell lines using GEPIA online analyze, qRT-PCR and immunohistochemistry. The biological behavior of GC cells was detected by CCK8, clone formation, transwell, wound healing, western blot, and flow cytometry assay. More in-depth mechanisms were studied. Results DLEU2 was significantly up-regulated in GC tissues and cell lines. The expression of DLEU2 was significantly associated with pathological grading and TNM stage of GC patients. Furthermore, knockdown of DLEU2 inhibited the proliferation, migration, and invasion of AGS and MKN-45 cells, while overexpression of DLEU2 promoted the proliferation, migration, and invasion of HGC-27 cells. MiR-30a-5p could directly bind to the 3’ UTR region of ETS2. Moreover, DLEU2 bound to miR-30a-5p through the same binding site, which facilitated the expression of ETS2. Knockdown of DLEU2 reduced the protein level of intracellular ETS2 and inhibited AKT phosphorylation, while overexpression of DLEU2 induced the expression of ETS2 and the phosphorylation of AKT. ETS2 was highly expressed in GC tissues. The expression of ETS2 was significantly associated with age, pathological grading, and TNM stage. ETS2 overexpression promoted cell proliferation and migration of AGS and MKN-45 cells. Furthermore, ETS2 overexpression rescued cell proliferation and migration inhibition induced by DLEU2 down-regulation and miR-30a-5p up-regulation in AGS and MKN-45 cells. Conclusions DLEU2 is a potential molecular target for GC treatment.

Regiella insecticola is a bacterial endosymbiont in insects that exhibits a negative effect on the fitness of hosts. Thus, it is not clear why this costly endosymbiont can persist in host populations. Here, we tested a hypothesis that the infection pattern and negative roles of the endosymbiont were not constant but environmentally dependent. The grain aphids Sitobion avenae, belonging to different genotypes and infected with Regiella or not, were used in this study. We found that S. avenae populations were infected with Regiella, Hamiltonella defensa, Serratia symbiotica and Rickettsia. The predominant endosymbionts in the aphid populations varied with season. Serratia and Rickettsia were predominant from December to February while Regiella predominated from March to May. The vertical transmission of Regiella was poorer at high temperature, but following conditioning for seven generations, the transmission rate improved. Regiella inhibited the production of winged aphids at 25 °C, but it did not affect winged morph production at the higher temperatures of 28 °C and 31 °C. Regiella infection decreased the intrinsic rate of increase (rm) of aphids at 25 °C and 28 °C. However, at 31 °C, the effect of Regiella on the rm varied depending on the aphid genotype and density. Thus, the negative effects of this endosymbiont on its host were environmentally dependent.

The severe local thermal trauma activates a number of systemic inflammatory mediators, such as TNF-α, NF-κB, resulting in a disruption of gut barrier. The gastrointestinal tight junction (TJ) is highly regulated by membrane-associated proteins including zonula occludens protein-1 (ZO-1) and occludin, which can be modulated by inflammatory cytokines. As splenectomy has been shown to reduce secretion of cytokines, we hypothesized that (1) severe scald injury up-regulates TNF-α and NF-κB, meanwhile down-regulates expression of ZO-1 and occludin, leading to the increased intestinal permeability, and (2) splenectomy can prevent the burn-induced decrease in ZO-1 and occludin expression, resulting in improved intestinal barrier. Wistar rats undergoing a 30% total body surface area (TBSA) thermal trauma were randomized to receive an accessorial splenectomy meanwhile or not. Intestinal injury was assessed by histological morphological analysis, and serum endotoxin levels, TNF-α, NF-κB, ZO-1 and occludin levels were detected by Western blotting in the terminal ileum mucosal tissue. 30% TBSA burn caused a significant increase in serum endotoxin levels, but NF-κB, and TNF-α, and the average intestinal villus height and mucosal thickness were decreased significantly. Burn injury could also markedly decrease the levels of ZO-1 and occludin in terminal ileum mucosal tissue (all P

Potato virus Y (PVY) and Myzus persicae are important pests of tobacco and potato crops. Myzus persicae can transmit PVY in a non-persistent manner. In this study, we investigated whether tobacco plants infected with PVY affected the performance and behavior of M. persicae by comparing growth, reproduction, and stylet penetration behaviors of M. persicae on PVY-infected vs. noninfected plants. We found that body and cornicle length, body and head width, and distance between compound eyes were significantly smaller in adult M. persicae reared on infected tobacco plants. Electrical penetration graph (EPG) recordings showed that the time spent on the plant before the first probe and the duration of the first probe increased significantly when M. persicae fed on PVY-infected rather than noninfected plants. The number of probes made by aphids on infected plants in the first hour was also greater than on healthy plants. Furthermore, M. persicae had a slightly higher net reproductive rate (R 0) when on infected tobacco plants than on noninfected plants. In summary, our data indicated that PVY infection had a negative effect on the growth of M. persicae. We suggest that the increased stylet penetration behavior of M. persicae on infected plants may be associated with increased virus acquisition and transmission.

Polyphagous cotton-melon aphid populations usually comprise cotton- and cucurbit-specialized biotypes. Host-specialized aphids are prone to food shortages. Cucumber, the favourite food of cucurbit-specialized aphids, is usually absent during autumn and winter in Nanjing, China. Therefore, suboptimal host plants act as refuges and govern the population dynamics of this aphid. The species, growth stages and leaf ages of host plants that cotton- and cucurbit-specialized aphids potentially could use were explored in this study. Cotton-specialized aphids were found to use wild chrysanthemum, potato, zucchini, pumpkin and flowering cucumber besides cotton, whilst cucurbit-specialized aphids were able to utilize potato, zucchini, pumpkin and mature cotton besides cucumber. The population dynamics and genotype frequencies of aphids on hibiscus, cotton, zucchini, cucumber and pumpkin showed that cotton-melon aphids on cucumber could transfer onto mature cotton. Aphids on zucchini shared microsatellite genotypes with aphids on cotton and cucumber. The predominant genotype of aphids on cotton was found on hibiscus, but the predominant genotype on cucumber was not found on hibiscus. Host-specialized aphids clearly have refuges during food shortages. Hibiscus is an overwintering host for cotton-specialized aphids but not for cucurbit-aphids. Removing refuges or managing aphids on refuges could potentially be an effective method to control cotton-melon aphids.

Reflectance and SPAD readings were measured in rice grown under different nitrogen fertilizer rates and infested with different numbers of brown planthopper (BPH), Nilaparvata lugens, to assess the relationships among these variables. The results showed that SPAD readings and reflectance from rice were significantly affected by BPH infestations and nitrogen fertilizer rates, whereas there was no interaction between the two factors. SPAD readings and reflectance decreased as BPH infestations increased but they increased as nitrogen fertilizer rates were increased. SPAD readings varied with position of leaf on the same stem of rice. The fourth and fifth leaves were more sensitive to BPH infestations than the first and second regardless of application rates of urea. The ratio indices of SPAD readings of the fourth to first leaf (RSPAD4/1), and fourth to second leaf (RSPAD4/2) were significantly related to BPH infestations, and they were relatively independent of nitrogen fertilizer rates in the single stem rice. The spectral reflectance from rice canopy significantly decreased in the near-infrared wavelength range as BPH infestations increased. The modified chlorophyll absorption ratio index (MCARI710) was found more suitable to relate the numbers of BPH under different nitrogen fertilizer rates and durations of BPH infestation. The main effects of BPH infestations on SPAD reading and reflectance indices were consistent regardless of nitrogen application rates. Therefore, SPAD reading and spectral indices have potential to detect BPH infestations in rice fields.

Previous studies have indicated a direct effect of μ-opioid receptors on tumor progression or recurrence. An A118G polymorphism in the μ-opioid receptor gene was believed to play an important role in this carcinogenic process. The aim of the present study was to investigate the association between the A118G polymorphism and the risk of esophageal squamous cell carcinoma (ESCC) in a Chinese population. The case–control study included 260 cancer patients and 291 controls from a Chinese Han and Chinese TuJia population in Enshi region, China. Genotypes were determined by TaqMan platform. Odds ratios (ORs) and 95 % confidence intervals (CIs) were calculated using multivariate unconditional logistic regression. Compared with the G/G genotype, the A/A genotype exhibited a significantly elevated risk for ESCC (OR = 3.12, 95 % CI [1], 1.11–6.01). A significant interaction between the A118G polymorphism and age, smoking status, and family history of cancer was also found (OR = 2.25, 95 % CI 1.36–4.12; OR = 1.75, 95 % CI 1.23–2.32; OR = 3.14, 95 % CI 1.31–7.28, respectively). The A118G polymorphism in the μ-opioid receptor gene might be associated with the risk of ESCC in Chinese population.

Let {Xn, n ≥ 1} be a sequence of identically distributed ρ−-mixing random variables and set Sn = Σi=1nXi, n ≥ 1, the sufficient and necessary conditions for the existence of moments of supn≥1 |Sn/n1/r|p(0 0) are given, which are the same as that in the independent case.

In this paper, in order to predict the residual deformation of thick spherical structure, a welding program is compiled in APDL language based on Ansys and a numerical welding experiment of a welding example is carried out. The temperature field of welding was simulated firstly, then a thermal-structure coupling analysis was carried out, and at last the residual stress and deformation after welding were got. After that, the numerical experiment result was compared with physical experiment one. The comparative analysis shows that the numerical simulation fits well with physical experiment. On the basis of that, a three-dimensional numerical experiment of a thick spherical shell structure was carried out to get the changing rule of stress and deformation of a thick spherical shell structure during welding. The research is of great value to the prediction of residual deformation and high precision machining.

Muyingle is a new type of health food prepared from marine organisms. The mammotropic action of Muyingle was investigated by studying its effect on mammary glands and pituitary glands of lactating mice and the survival rate of suckling mice. The results showed that the mammotropic action of Muyingle was very effective. The survival rates of suckling mice were 92.90% for the treated group and 0 for the control group (p