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Permafrost thaw could increase methane (CH4) emissions, which largely depends on CH4 production driven by methanogenic archaea. However, large-scale evidence regarding key methanogenic taxa and their relative importance to abiotic factors in mediating methanogenesis remains limited. Here, we explored the methanogenic community, potential CH4 production and its determinants in the active layer and permafrost deposits based on soil samples acquired from 12 swamp meadow sites along a ∼1000 km permafrost transect on the Tibetan Plateau. Our results revealed lower CH4 production potential, mcrA gene abundance, and richness in the permafrost layer than those in the active layer. CH4 production potential in both soil layers was regulated by microbial and abiotic factors. Of the microbial properties, marker OTUs, rather than the abundance and diversity of methanogens, stimulated CH4 production potential. Marker OTUs differed between the two soil layers with hydrogenotrophic Methanocellales and facultative acetoclastic Methanosarcina predominant in regulating CH4 production potential in the permafrost and active layer, respectively. Besides microbial drivers, CH4 production potential increased with the carbon/nitrogen (C/N) ratio in both soil layers and was also stimulated by soil moisture in the permafrost layer. These results provide empirical evidence for model improvements to better predict permafrost carbon feedback to climate warming.

One environmentally friendly method used to manage Bactrocera dorsalis (Hendel), a key agricultural pest of substantial economic importance, is the sterile insect technique (SIT). Nevertheless, several deficiencies related to this strategy impair the success of the SIT, including the inferior performance of released sterile males compared with wild males, which could be partly solved by the utilization of gut symbionts as probiotic dietary components. In this study, a culture-dependent method was used to isolate and characterize gut-associated bacterial species in adult B. dorsalis genetic sexing strain (GSS) males. In addition, three bacterial isolates from the Enterobacteriaceae family, namely, Enterobacter sp., Morganella morganii, and Moellerella wisconsensis, were used as supplements in larval and adult diets to assess their effects on the life-history traits of irradiated males. Consistent with many previous studies, Enterobacter spp. was shown to be beneficial, with some quality control indices, such as adult size, pupal weight, survival rate under stress and nutritionally rich conditions, and mating competitiveness, being significantly increased, while slight nonsignificant increases in emergence rate and flight ability were observed. Conversely, the M. morganii and M. wisconsensis strains both had negative effects on irradiated male fitness and mating competitiveness. Our results, in combination with those of earlier studies, can contribute to improving the effectiveness of SIT application by enhancing the different aspects of augmentative rearing and biological traits of pests under laboratory rearing conditions.

Climate warming can alter ecosystem carbon (C) balance and also the composition of soil organic matter (SOM), with important local and global implications. However, the extent to which rising temperature affects SOM composition in permafrost ecosystems remains poorly understood. Here, we experimentally warmed a permafrost ecosystem by open‐top chambers (OTCs) on the Tibetan Plateau for 4 years to quantify the responses of C inputs via vegetation production, C losses via soil respiration and soil organic carbon (SOC) stocks in the top 30 cm. We also characterized the molecular composition of SOM using ¹³C nuclear magnetic resonance (NMR) and biomarker analyses. The results indicated that warming treatment significantly increased root biomass, soil respiration, heterotrophic respiration and its contribution to soil respiration by 16.7%, 49.0%, 63.2% and 9.5% respectively. While we observed no change in SOC stocks, warming altered SOM composition in the 0–10 cm layer during the fourth experimental year. Warming increased the abundance of the alkyl C component (3.9%) and decreased aromatic C (5.1%), primarily lignin. The decrease in lignin‐derived compounds was attributable to the increased soil phenol oxidase activity. Overall, the substantial increase in heterotrophic respiration and rapid degradation of relatively recalcitrant C components such as lignin demonstrate that Tibetan SOC stocks are vulnerable to climate warming, which could trigger positive C–climate feedback in a warmer world. A free Plain Language Summary can be found within the Supporting Information of this article.

Diachasmimorpha longicaudata is the most widely used endoparasitoid in biocontrol programmes against various species of tephritids and is continuously mass-reared under laboratory conditions at a constant temperature; however, little is known about how varying the temperature might affect the effectiveness of the mass rearing of immature D. longicaudata. This study aimed to determine the optimum temperature for the development of larvae D. longicaudata the larvae of its host, Bactrocera dorsalis. Third-instar B. dorsalis were exposed for 4 h to five pairs of parasitoids, and then they were kept at one of six temperatures ranging from 19°C to 34°C. The activities of three major antioxidant enzymes (CAT, POX, SOD) were individually measured 4, 24, 48 and 72 h after exposure to each of the six temperatures. The results were as follows: for CAT the highest CAT activities were recorded at 25°C (intervals 5-24 h and 25-48 h), at 28°C (interval 0-4 h) and at 31°C (interval 49-72 h), and for POX and SOD identically at 25°C (intervals 0-4 h, 5-24 h) and at 31°C (intervals 25-48 h, 49-72 h), respectively. Subsequently, the effects keeping the parasitized larvae at these different temperatures on the biological attributes of D. longicaudata reared under laboratory conditions were investigated. The percentage of their eggs that hatched, percentage of adults that emerged, pupal weight and longevity were significantly greater than that recorded for the control when the parasitized host larvae were kept at 28°C for 4 h, 25°C for 5 and 48 h and 31°C for 49 and 72 h.

We evaluated a protein bait based on an enzymatically hydrolyzed beer yeast and two widely used baits including a sugar + vinegar + wine mixture and apple cider vinegar for their ability to trap Drosophila suzukii (Matsumura) in the laboratory and outdoors. The protein bait was a more attractive lure than the other tested baits, with the protein bait capturing significantly more female and male adults at different developmental stages than the other baits. Furthermore, the protein bait with 20% vinegar attracted significantly more adult flies than the other baits, and the protein bait without dilution attracted the most adults. Except for the addition of 0.05% spinosad, increased insecticide content in protein bait reduced its attractiveness to adult flies. Moreover, we found that D. suzukii has a bimodal activity pattern in visiting protein bait, where maximum activity occurs during 8:00-10:00 a.m. and 14:00-16:00 p.m. The antennae and maxillary palpi played an important role in detecting the chemicals emitted from the protein bait, as the number of intact flies that responded to new protein bait was significantly higher than the number of flies without antennae that responded, but almost 15% of defective flies still responded to the protein bait. Our results suggested that the protein bait based on spent brewery yeast could be a promising alternative for D. suzukii population monitoring and for managing this pest when combined with bioinsecticides, providing guidance for using this protein bait as a component of integrated pest management.

Input of labile carbon may accelerate the decomposition of existing soil organic matter (priming effect), with the priming intensity depending on changes in soil nitrogen availability after permafrost thaw. However, experimental evidence for the linkage between the priming effect and post-thaw nitrogen availability is unavailable. Here we test the hypothesis that elevated nitrogen availability after permafrost collapse inhibits the priming effect by increasing microbial metabolic efficiency based on a combination of thermokarst-induced natural nitrogen gradient and nitrogen addition experiment. We find a negative correlation between the priming intensity and soil total dissolved nitrogen concentration along the thaw sequence. The negative effect is confirmed by the reduced priming effect after nitrogen addition. In contrast to the prevailing view, this nitrogen-regulated priming intensity is independent of extracellular enzyme activities but associated with microbial metabolic efficiency. These findings demonstrate that post-thaw nitrogen availability regulates topsoil carbon dynamics through its modification of microbial metabolic efficiency., Soil nitrogen availability may alter carbon dynamics after permafrost thaw, but experimental evidence for this carbon-nitrogen interaction is still lacking. Here the authors show that elevated post-thaw nitrogen availability inhibits soil carbon release through its enhancement in microbial metabolic efficiency.

The present study aimed to determine whether maslinic acid effectively inhibits the proliferation of MKN28 cells, and to investigate the mechanisms underlying its antitumor functions. MKN28 cell viability was evaluated using a Cell Counting Kit-8, cell proliferation was analyzed by a colony formation assay and flow cytometry was used to investigate the rate of apoptosis. Western blot analysis was performed in order to determine the differential expression levels of Janus kinase (JAK), signal transducer and activator of transcription 3 (STAT3) and apoptosis associated proteins B-cell lymphoma 2 (Bcl-2), Bcl-2 associated X protein (Bax) and Bcl-2 associated agonist of cell death (Bad). Interleukin-6 (IL-6) concentration was evaluated using ELISA. IL-6 and anti-IL-6 antibodies were used to investigate the role of IL-6 in MKN28 cells treated with maslinic acid proliferation, and the STAT3 phosphorylation rates. The results demonstrated that maslinic acid treatment significantly reduced cell proliferation, induced apoptosis and was accompanied by a significant decrease in Bcl-2, Bax and Bad expression levels. Maslinic acid treatment also resulted in the downregulation of phosphorylated-STAT3 and JAK2, and significantly inhibited the protein expression of IL-6. Maslinic acid is able to inhibit MKN28 cell proliferation and the phosphorylation of STAT3 by downregulating the expression of IL-6. These results suggest that maslinic acid suppresses the growth of MKN28 cells by inducing apoptosis via its inhibition of the IL-6/JAK/STAT3 signaling cascade.

This study aims to evaluate several life-history traits of a T. drosophilae population from southern China and its parasitic preference of three Drosophila species. For mated T. drosophilae females, the mean oviposition and parasitization period were 27.20 and 37.80 d, respectively. The daily mean parasitization rate was 59.24% per female and the lifetime number of emerged progeny was 134.30 per female. Trichopria drosophilae females survived 37.90 and 71.61 d under host-provided and host-deprived conditions, respectively. To assess the potential for unmated reproduction in T. drosophilae, the mean oviposition and parasitization period of unmated females was 22.90 and 47.70 d, respectively. They had a daily mean parasitization rate of 64.68%, produced a total of 114.80 offspring over their lifetime, and survived 52 d. Moreover, T. drosophilae showed a preference towards D. suzukii based on the total number of emerged offspring under a choice test. Our findings indicate that T. drosophilae from southern China appears to be suitable for the control of D. suzukii in invaded areas, due to its reproductive potential.

Novel targeted therapies need to be developed for gastric cancer, the third most common cancer type and the second most common cause of cancer-related mortality in China. Previous studies indicate that angiopoietin (Ang)-2 serves a role in the proliferation, migration, invasion and adhesion of malignant cells. The present study identified, using functional studies, that exogenous expression of miR-218 increased migration of NCI-87 and HGC-27 gastric cancer cells, which coincided with a reduction in the expression of Ang-2. In addition, intratumoral delivery of miR-218 inhibited proliferation and angiogenesis of gastric cancer cells in vivo, with a corresponding decreased in Ang-2 expression. These results indicate that miR-218 serves an important role in gastric cancer tumorigenesis through regulating the expression of Ang-2. Therefore, components of miR-218/Ang-2 signaling could provide novel therapeutic targets for the treatment of gastric cancer.

Major depressive disorder (MDD), one of the most frequently encountered forms of mental illness and a leading cause of disability worldwide, poses a major challenge to genetic analysis. To date, no robustly replicated genetic loci have been identified, despite analysis of more than 9,000 cases. Here, using low-coverage whole-genome sequencing of 5,303 Chinese women with recurrent MDD selected to reduce phenotypic heterogeneity, and 5,337 controls screened to exclude MDD, we identified, and subsequently replicated in an independent sample, two loci contributing to risk of MDD on chromosome 10: one near the SIRT1 gene (P = 2.53 × 10(-10)), the other in an intron of the LHPP gene (P = 6.45 × 10(-12)). Analysis of 4,509 cases with a severe subtype of MDD, melancholia, yielded an increased genetic signal at the SIRT1 locus. We attribute our success to the recruitment of relatively homogeneous cases with severe illness.

This study explored the potential for Bactrocera dorsalis (Hendel) (Diptera: Tephritidae) larvae hatched from irradiated eggs as hosts for Diachasmimorpha longicaudata (Ashmead) (Hymenoptera: Braconidae). B. dorsalis eggs of three different ages (12-, 24-, and 36-h old) were analyzed for hatchability, pupation rate, pupal weight, emergence rate, and sex ratio after exposure to different doses of radiation (5 and 10 Gy) at different dose rates (1 and 6 Gy/min). For the eggs of different ages exposed to radiation, only the hatchability and pupal weight of 36-h-old eggs exposed to the dose rate of 1 Gy/min were not affected; therefore, 6 Gy/min was not suitable for irradiating eggs. The viability of the parents and progenies of D. longicaudata when the parents were reared from 36-h-old eggs irradiated at nine different doses (0, 5, 10, 15, 20, 25, 30, 35, and 40 Gy) under laboratory conditions were investigated. The emergence percentage, sex ratio, and longevity of parasitoids developed from irradiated eggs were similar to those reared from nonirradiated hosts. A significant increase in larva mortality was observed for the eggs irradiated at doses above 25 Gy, and no redundant adult flies emerged at doses above 15 Gy. Hence, for B. dorsalis eggs to be applied in the mass rearing of D. longicaudata, the age of 36 h and a dose of 20-25 Gy are the optimal parameters. The results reveal that hosts and parasitoids need not be separated, enabling a reduction in cost, labor, and time and resulting in an improved mass rearing procedure for D. longicaudata.

Multiple endocrine neoplasia type 1 (MEN1) is an endocrine cancer syndrome occurred on multiple endocrine tissues caused by MEN1 gene. Its protein product is 610 amino acids in length, named Menin. Creb-regulated transcriptional coactivator 1 (CRTC1) activates transcription through enhancing the interaction of CREB1 with TAF4. THOC5 was the fifth member of a subcomplex of the transcription/export complex (THO), which is involved in the nuclear export of a subset of mRNAs. In this report, we found an interesting regulation pattern between these three genes. CRTC1 promotes THOC5 nuclear export and Menin reverses this process. Both Menin and THOC5 inhibit CRTC1 activation on G6Pase promoter in a synergistic manner, suggesting the interplay of these three genes regulates gene expression.

Background The prevalence of major depressive disorder (MDD) is higher in those with low levels of educational attainment, the unemployed and those with low social status. However the extent to which these factors cause MDD is unclear. Most of the available data comes from studies in developed countries, and these findings may not extrapolate to developing countries. Examining the relationship between MDD and socio economic status in China is likely to add to the debate because of the radical economic and social changes occurring in China over the last 30 years. Principal findings We report results from 3,639 Chinese women with recurrent MDD and 3,800 controls. Highly significant odds ratios (ORs) were observed between MDD and full time employment (OR = 0.36, 95% CI = 0.25–0.46, logP = 78), social status (OR = 0.83, 95% CI = 0.77–0.87, logP = 13.3) and education attainment (OR = 0.90, 95% CI = 0.86–0.90, logP = 6.8). We found a monotonic relationship between increasing age and increasing levels of educational attainment. Those with only primary school education have significantly more episodes of MDD (mean 6.5, P-value = 0.009) and have a clinically more severe disorder, while those with higher educational attainment are likely to manifest more comorbid anxiety disorders. Conclusions In China lower socioeconomic position is associated with increased rates of MDD, as it is elsewhere in the world. Significantly more episodes of MDD occur among those with lower educational attainment (rather than longer episodes of disease), consistent with the hypothesis that the lower socioeconomic position increases the likelihood of developing MDD. The phenomenology of MDD varies according to the degree of educational attainment: higher educational attainment not only appears to protect against MDD but alters its presentation, to a more anxious phenotype.

Mol Med Rep 12:[Related article:] 8041–8047, 2015; DOI: 10.3892/mmr.2015.4459 Following the publication of this article, an interested reader drew to our attention anomalies associated with the presentation of Fig. 4A. In the original presentation of the Figure, different representations of the same photomicrograph were inadvertently used for the panels labelled 'N', 'H-R', 'H-R + NAC' and 'H-R + SB203580'. This error arose as a consequence of an incorrect ordering of our original image numbers. A corrected version of Fig. 4A is provided below, featuring the appropriate data for each of the five panels listed above. This Figure was intended to show how, compared with the normoxic control group, the invasiveness of the SGC-7901 gastric cancer cells was markedly increased under hypoxia-reoxygenation (H-R) conditions, although pretreatment with N-acetyl cysteine (NAC; 30 mmol/l) or indanyloxyacetic acid 94 (IAA-94; 40 μmol/l), inhibited the invasiveness resulting from H-R exposure. Similarly, treatment with the inhibitor of p38 mitogen-activated protein kinase, SB203580 (10 μmol/l), also inhibited the cell invasiveness induced under the H-R conditions. We sincerely apologize for this mistake, and thank the reader of our article who drew this matter to our attention. Furthermore, we regret any inconvenience this mistake has caused.