MicroRNA-200c-targeted contactin 1 facilitates the replication of influenza A virus by accelerating the degradation of MAVS.

Influenza A viruses (IAVs) continuously challenge the poultry industry and human health. Elucidation of the host factors that modulate the IAV lifecycle is vital for developing antiviral drugs and vaccines. In this study, we infected A549 cells with IAVs and found that host protein contactin-1 (CNTN1), a member of the immunoglobulin superfamily, enhanced viral replication. Bioinformatic prediction and experimental validation indicated that the expression of CNTN1 was reduced by microRNA-200c (miR-200c) through directly targeting. We further showed that CNTN1-modulated viral replication in A549 cells is dependent on type I interferon signaling. Co-immunoprecipitation experiments revealed that CNTN1 specifically interacts with MAVS and promotes its proteasomal degradation by removing its K63-linked ubiquitination. Moreover, we discovered that the deubiquitinase USP25 is recruited by CNTN1 to catalyze the deubiquitination of K63-linked MAVS. Consequently, the CNTN1-induced degradation cascade of MAVS blocked RIG-I-MAVS-mediated interferon signaling, leading to enhanced viral replication. Taken together, our data reveal novel roles of CNTN1 in the type I interferon pathway and regulatory mechanism of IAV replication.

[Construction and acceptability of different complementary foods texture in infants and young children aged 6 to 23 months].

OBJECTIVE: To construct the complementary food texture in infants and young children aged 6 to 23 months, and observe the acceptability of complementary food of different months old infants. METHODS: Based on the domestic and foreign guidelines, consensus and literatures on complementary feeding, and combined with the characteristics of children's growth and development in China. The complementary food texture index of 6-23 months old infants and young children was constructed. One province was selected in the south and north respectively, one city and one rural area was selected as the observation point in each province. The stratified random sampling principle was adopted in each observation point, 240 infants and young children were selected for the acceptability study. According to the food type, 12 common foods were selected to make the complementary food toolkit. The parents were instructed to make complementary food at home according to the corresponding month age, observe and record the acceptability of single/mixed complementary food feeding. RESULTS: The complementary food texture index of 6 months, 7-8 months, 9-11 months, 12-17 months, 18-23 months was constructed. Caregivers could make complementary food at the corresponding month age according to the established complementary food texture index. The acceptability of single complementary food for infants and young children aged 6-23 months was 98.3%, 98.7%, 99.8%, 96.9% and 97.5%, respectively. The acceptability of mixed complementary food for children aged 7-23 months was 98.3%, 99.6%, 93.8% and 97.5%, respectively. CONCLUSION: The complementary food texture index of different month age can be made at home, and the acceptability of different texture is good.

[Relationship between the percentage of energy intake from macronutrients and obesity among adult residents in 15 provinces of China in 1991-2018].

OBJECTIVE: To explore the relationship between the percentage of energy intake from macronutrients and obesity in Chinese adult residents, and analyze the cut-off values of macronutrients for predicting obesity. METHODS: Data was collected in China Health and Nutrition Survey(CHNS)in 1991-2018. Adults who participated in at least two waves of the surveys and were not obese at baseline were selected as the study subjects. Obesity was defined as body mass index(BMI)≥28.0 kg/m~2. Generalized estimating equation was used to analyze the relationship between the percentage of energy intake from macronutrients and BMI and obesity, and receiver operating characteristic curve(ROC) was used to analyze the cut-off values of percentage of energy intake from macronutrients to predict obesity. RESULTS: The percentage of energy intake from protein and fat of adult residents in 15 provinces(autonomous regions and municipalities) in China showed an increasing trend(P<0.01), and the percentage of energy intake from carbohydrate showed a decreasing trend(P<0.01) between 1991 and 2018. After adjusting for covariates, the group of percentage of energy intake from fat in 20%～30%(ß=0.05, 95%CI 0.01-0.08)and ≥30%(ß=0.15, 95%CI 0.11-0.18)were positively correlated with BMI compared with the group of percentage of energy intake from fat <20%, and the risk of obesity in 20%-30% and ≥ 30% was increased by 17%(OR=1.17, 95%CI 1.04-1.31)and 6%(OR=1.06, 95%CI 1.24-1.56), respectively. Compared with the group of the percentage of energy intake from carbohydrate < 50%, the group of 50% to 65%(ß=-0.08, 95% CI-0.11--0.05) and ≥ 65%(ß=-0.17, 95%CI-0.20--0.13) was negatively correlated with BMI, and the percentage of energy intake from carbohydrate ≥ 65% reduced the risk of obesity(OR=0.71, 95%CI 0.63-0.80). CONCLUSION: Carbohydrate intake was inversely correlated with the risk of obesity, and fat intake was positively correlated with the risk of obesity. Moderate intake of carbohydrates and reduced fat intake can prevent obesity.

The PB1 protein of influenza A virus inhibits the innate immune response by targeting MAVS for NBR1-mediated selective autophagic degradation.

Influenza A virus (IAV) has evolved various strategies to counteract the innate immune response using different viral proteins. However, the mechanism is not fully elucidated. In this study, we identified the PB1 protein of H7N9 virus as a new negative regulator of virus- or poly(I:C)-stimulated IFN induction and specifically interacted with and destabilized MAVS. A subsequent study revealed that PB1 promoted E3 ligase RNF5 to catalyze K27-linked polyubiquitination of MAVS at Lys362 and Lys461. Moreover, we found that PB1 preferentially associated with a selective autophagic receptor neighbor of BRCA1 (NBR1) that recognizes ubiquitinated MAVS and delivers it to autophagosomes for degradation. The degradation cascade mediated by PB1 facilitates H7N9 virus infection by blocking the RIG-I-MAVS-mediated innate signaling pathway. Taken together, these data uncover a negative regulatory mechanism involving the PB1-RNF5-MAVS-NBR1 axis and provide insights into an evasion strategy employed by influenza virus that involves selective autophagy and innate signaling pathways.

Metabolomics reveal metabolic variation caused by co-culture of Arthrobacter ureafaciens and Trichoderma harzianum and their impacts on wheat germination.

Arthrobacter ureafaciens DnL1-1 is a bacterium used for atrazine degradation, while Trichoderma harzianum LTR-2 is a widely used biocontrol fungus. In this study, a liquid co-cultivation of these two organisms was initially tested. The significant changes in the metabolome of fermentation liquors were investigated based on cultivation techniques (single-cultured and co-cultured DnL1-1 and LTR-2) using an UPLC-QTOF-MS in an untargeted metabolomic approach. Principle components analysis (PCA) and partial least squares discriminant analysis (PLS-DA) supervised modelling revealed modifications of the metabolic profiles in fermentation liquors as a function of interactions between different strains. Compared with pure-cultivation of DnL1-1, 51 compounds were altered during the cocultivation, with unique and significant differences in the abundance of organic nitrogen compounds (e.g. carnitine, acylcarnitine 4:0, acylcarnitine 5:0, 3-dehydroxycarnitine and O-acetyl-L-carnitine) and trans-zeatin riboside. Nevertheless, compared with pure-cultivation of LTR-2, the abundance of 157 compounds, including amino acids, soluble sugars, organic acids, indoles and derivatives, nucleosides, and others, changed significantly in the cocultivation. Among them, the concentration of tryptophan, which is a precursor to indoleacetic acid, indoleacetic acid, aspartic acid, and L-glutamic acid increased while that of most soluble sugars decreased upon cocultivation. The fermentation filtrates of co-cultivation of LTR-2 and DnL1-1 showed significant promoting effects on germination and radicle length of wheat. A subsequent experiment demonstrated synergistic effects of differential metabolites caused by co-cultivation of DnL1-1 and LTR-2 on wheat germination. Comprehensive metabolic profiling may provide valuable information on the effects of DnL1-1 and LTR-2 on wheat growth.

Diterpenoids with an unusual tricyclo[10.3.0.02,9]pentadecane skeleton from Pedilanthus tithymaloides as multidrug resistance modulators.

Three new diterpenoids with an unusual carbon skeleton, pedilanins A-C (1-3), and nine new jatrophane diterpenoids, pedilanins D-L (4-12), along with five known ones (13-17), were isolated from Pedilanthus tithymaloides. Compounds 1-3 characterize an unprecedented tricyclo[10.3.0.02,9]pentadecane skeleton. Compounds 4-8 are rare examples of the jatrophanes bearing a cyclic hemiketal substructure. Their structures were determined by an extensive analysis of HRESIMS, NMR, quantum-chemical calculation, DP4+ probability, and X-ray crystallographic data. In the bioassay, compounds 1-12 dramatically reversed multidrug resistance in cancer cells with the fold-reversals ranging from 17.9 to 396.8 at the noncytotoxic concentration of 10 µM. The mechanism results indicated that compounds 2 and 3 inhibited the P-glycoprotein (Pgp) transporter function, thus reversing the drug resistance.

[Cost-benefit analysis on the intervention of application iron-fortified soy sauce for anemia in Deqing 15-54 years women, Zhejiang].

OBJECTIVE: To make a cost-benefit analysis on anemia intervention with iron-fortified soy sauce in 15-54 years old women. METHODS: The study was conducted in Deqing county, Zhejiang province in 2012-2013. A total 585 women as sampling size were estimated with statistical model and randomly selected by probability proportionate to size sampling. Hemoglobin were measured before intervention and after 15 months. The cost of the intervention project were collected with manpower, communication and other invest. The benefit was estimated with profiling model. RESULTS: After the intervention, the anemia prevalence of sampled women decreased from 31.1% to 21.9%(P<0.01). The major cost of the project was 156 400 RMB, and total benefits result ing from projects were 1 448 485 RMB. The cost-benefit ratio of the project is 1∶9.49. If investing one yuan can produce economic benefits of nearly 9.49 yuan, therefore, the intervention projectis worth to be scaling up. Sensitivity analysis showed the result of this study was stable. CONCLUSION: The intervention can significantly reduce the prevalence of anemia in women, and reduce the economic burden of the diseases. .

[Evaluation of the front-of-package warning labels of prepackaged food in China based on focus group discussion].

OBJECTIVE: To understand the public's perceptions and preferences on the designed front-of-package warning labels of prepackaged food, and to evaluate and identify the effective warning label. METHODS: A total of 116 participants were recruited from six provinces(autonomous regions/municipalities) in China. Focus group discussions were conducted with four types of warning labels on prepackaged food. And the score of attitude on different warning labels were compared. RESULTS: There was no difference in the total score of the four warning labels. Total score of black shield label was higher in citizen participants and college education level participants than in their respective counterparts(P<0.05). Parents or primary caregiver of children under 16 years old gave higher scores to each labels than their respective counterparts(P<0.05). The black shield label was most likely to attract the attention of the respondents, most likely to influence the decision on eating and drinking, and most likely to have an unhealthy warning effect. The yellow hexagonal label was least likely to attract the attention of the respondents, least likely to affect the decision to eat and drink food, and least likely to have an unhealthy warning effect. CONCLUSION: Black shield warning label is the most effective.

[Development and validation of the nutrient-rich food index for China].

OBJECTIVE: To select the nutrient-rich food(NRF) index applicable to the food characteristics of Chinese residents through population-based dietary quality validation. METHODS: Sixteen NRF indices were constructed based on the Chinese Food Composition Table and the Chinese Food Labelling Nutrient Reference Values, using 100 g as the base amount of food for calculation. The NRF indices were validated by the China Prime Diet Quality Score(CPDQS), a dietary quality assessment index, using food intake data collected from 14 068 adult residents in 15 provinces in 2018 under the China Health and Nutrition Survey. The CPDQS was used as the dependent variable and the dietary NRF index score was used as the independent variable. The multiple linear regression models were performed after adjusting the covariates and the NRF index with the largest coefficient of determination R~2 was used as the most appropriate index. RESULTS: Regression analysis showed that the R~2 of NRF8.2 index was the largest, which was 0.16. Dried legumes, fungi and algae, nuts, vegetables, eggs and aquatic products scored higher on the NRF8.2 index. The high scoring subgroups had higher average daily intakes of cereals and potatoes, vegetables, fruits, soybeans and nuts, dairy, eggs and aquatic products, as well as lower consumption of livestock and poultry meat, beverages, salt and cooking oil, compared to the low scoring subgroup on the Dietary NRF8.2 Index. In terms of nutrient intake, the medium and high NRF8.2 subgroups had relatively high intakes of energy, protein, vitamins and minerals and relatively low intakes of fat and sodium. CONCLUSION: The NRF8.2 index explains the maximum variation in CPDQS and is a relatively suitable NRF index for the Chinese population.

Effective extraction of tylosin and spiramycin from fermentation broth using thermo-responsive ethylene oxide/propylene oxide aqueous two-phase systems.

Recyclable aqueous two-phase systems with thermo-responsive phase-forming materials have been employed to separate macromolecules; however, these systems have achieved very limited separation efficiency for small molecules, such as antibiotics. In this study, aqueous two-phase systems composed of the ethylene oxide/propylene oxide copolymer and water were developed to extract alkaline antibiotics from the fermentation broth. In the aqueous two-phase systems with an ethylene oxide ratio of 20 and propylene oxide ratio of 80, the partition coefficients of tylosin and spiramycin reached 16.87 and 20.39, respectively, while the extraction recoveries were 70.67 and 86.70%, respectively. Coupled with mechanism analysis, we demonstrated the feasibility of extracting alkaline antibiotics using this aqueous two-phase system, especially for 16-membered macrolide antibiotics. The molecular dynamic simulation was employed to visualize the process of dual-phase formation and the partition behavior of antibiotics in an aqueous two-phase system. The dynamic simulation revealed the binding energy between the antibiotic and ethylene oxide/propylene oxide copolymers, which provides a simple indicator for screening suitable antibiotics in aqueous two-phase systems. Our recyclable aqueous two-phase systems provide a robust approach for the extraction of 16-membered macrolide antibiotics with ease of operation and high recovery rates, which is appropriate for large-scale extraction in the fermentation industry.

Chromosome doubling influences the morphological, physiological, biochemical and genetic traits related to essential oil biosynthesis of peppermint (Mentha piperita) under salinity stress.

Peppermint (Mentha piperita L.) is an important medicinal aromatic plant. In this study, the morphology, physiology, biochemistry and gene expression of chromosomes doubling peppermint (D1 lines) were analyzed. The analysis showed that D1 lines had larger, thicker and darker leaves, and stronger roots when planted in the pots, but delayed growth in the field condition. Under NaCl stress, the D1 lines increased cell oxidative defense through more active antioxidant enzymes and decreased the oxidative damages of cell membrane, leading to a significantly greater survival rate and photosynthesis intensity than WT lines. The size and density of glandular trichomes of D1 lines was larger, which contributed to its higher essential oil yield. In addition, chromosome doubling reduced the inhibition of NaCl stress on essential oil yield and quality, through changing the expression of genes in the oil biosynthesis pathway. The traits of chromosome doubling peppermint provide new technical and theoretical evidence for peppermint germplasm improvement.

[Cost-benefit analysis of Ying Yang Bao (YYB) intervention in 6 to 23 months rural infants].

OBJECTIVE: To study on the cost-benefit from anemia and stunting reduction of Ying Yang Bao(YYB) intervention in 6 to 23 months rural infants in the six counties of Shanxi, Hubei and Yunnan provinces. METHODS: YYB was distributed to 6-23 months infants in 6 counties by YYB nutrition intervention project. The numbers of childhood recovered from stunting and anemia was collected by a designed project monitoring plan. The cost-benefit was analyzed with PROFILING model as a nutritional microeconomic tool. RESULTS: Total numbers of monitored infants was 10 672 while the total cost of YYB intervention was estimated 2.57 million RMB. From 2012 to 2020, the total benefit was 14.92 million RMB from recover of stunting and anemia by YYB project and the average cost-benefit ratio of 6 counties was 1∶5.8. Sensitivity analysis showed the result of this study was stable. CONCLUSION: The YYB nutrition intervention for infants aged 6-23 months in the six counties of Shanxi, Hubei and Yunnan provinces showed a high cost-benefit ratio.

[Fat intake from pre-packaged foods among Chinese residents of 16 provinces in 2018].

OBJECTIVE: To investigate the impact of prepackaged food consumption on fat intake in 16 provinces of China in 2018. METHODS: Data used in present study was derived from the eleventh round of China Health and Nutrition Survey(CHNS), 17312 residents aged 6 and over were selected and their consumed information of pre-packaged food was collected. The consumption of pre-packaged food and fat intake from pre-packaged food in urban and rural areas, different age groups, different regions and different genders were calculated and compared. RESULTS: The median intake of fat from pre-packaged food among subjects and consumers were 33.6 g/d and 34.7 g/d, respectively.73.5% of the intake of fat from pre-packaged food comes from vegetable oil. CONCLUSION: Vegetable oil was the main source of fat from pre-packaged food for Chinese residents.

Identification of STXBP6-IRF1 positive feedback loop in regulation of PD-L1 in cancer.

The clinical success of immune checkpoint blockade against diverse human cancers highlights the critical importance of insightful understanding into mechanisms underlying PD-L1 regulation. IFN-γ released by intratumoral lymphocytes regulates PD-L1 expression in tumor cells through JAK-STAT-IRF1 pathway, while the molecular events prime IRF1 to translocate into nucleus are still obscure. Here we identified STXBP6, previously recognized involving in SNARE complex assembly, negatively regulates PD-L1 transcription via retention of IRF1 in cytoplasm. IFN-γ exposure stimulates accumulation of cytosolic IRF1, which eventually saturates STXBP6 and triggers nuclear translocation of IRF1. Nuclear IRF1 in turn inhibits STXBP6 expression and thereby liberates more IRF1 to migrate to nucleus. Therefore, we identified a novel positive feedback loop between STXBP6 and IRF1 in regulation of PD-L1 expression in cancer. Furthermore, we demonstrate STXBP6 overexpression significantly inhibits T cell activation both in vitro and in vivo. These findings offer new insight into the complexity of PD-L1 expression in cancer and suggest a valuable measure to predict the response to PD-1/PD-L1-based immunotherapy.

The Nucleoprotein of H7N9 Influenza Virus Positively Regulates TRAF3-Mediated Innate Signaling and Attenuates Viral Virulence in Mice.

H7N9 influenza A virus (IAV) is an emerged contagious pathogen that may cause severe human infections, even death. Understanding the precise cross talk between virus and host is vital for the development of effective vaccines and therapeutics. In the present study, we identified the nucleoprotein (NP) of H7N9 IAV as a positive regulator of RIG-I like receptor (RLR)-mediated signaling. Based on a loss-of-function strategy, we replaced H1N1 (mouse-adapted PR8 strain) NP with H7N9 NP, by using reverse genetics, and found that the replication and pathogenicity of recombinant PR8-H7N9NP (rPR8-H7N9NP) were significantly attenuated in cells and mice. Biochemical and cellular analyses revealed that H7N9 NP specifically interacts with tumor necrosis factor receptor (TNFR)-associated factor 3 (TRAF3) after viral infection. Subsequently, we identified a PXXQXS motif in the H7N9 NP that may be a determinant for the NP and TRAF3 interaction. Furthermore, H7N9 NP stabilized TRAF3 expression via competitively binding to TRAF3 with cellular inhibitor of apoptosis 2 (cIAP2), leading to the inhibition of the Lys48-linked polyubiquitination and degradation of TRAF3. Taken together, these data uncover a novel mechanism by which the NP of H7N9 IAV positively regulates TRAF3-mediated type I interferon signaling. Our findings provide insights into virus and host survival strategies that involve a specific viral protein that modulates an appropriate immune response in hosts.IMPORTANCE The NS1, PB2, PA-X, and PB1-F2 proteins of influenza A virus (IAV) are known to employ various strategies to counteract and evade host defenses. However, the viral components responsible for the activation of innate immune signaling remain elusive. Here, we demonstrate for the first time that the NP of H7N9 IAV specifically associates with and stabilizes the important adaptor molecule TRAF3, which potentiates RLR-mediated type I interferon induction. Moreover, we reveal that this H7N9 NP protein prevents the interaction between TRAF3 and cIAP2 that mediates Lys48-linked polyubiquitination of TRAF3 for degradation. The current study revealed a novel mechanism by which H7N9 NP upregulates TRAF3-mediated type I interferon production, leading to attenuation of viral replication and pathogenicity in cells and mice. Our finding provides a possible explanation for virus and host commensalism via viral manipulation of the host immune system.

Near-Complete Genomes of Two Trichoderma Species: A Resource for Biological Control of Plant Pathogens.

Trichoderma species are widely used to control fungal and nematode diseases of crops. To date, only one complete Trichoderma genome has been sequenced, T. reesei QM6a, a model fungus for industrial enzyme production, while the species or strains used for biological control of plant diseases are only available as draft genomes. Previously, we demonstrated that two Trichoderma strains (T. afroharzianum and T. cyanodichotomus) provide effective control of nematode and fungal plant pathogens. Based on deep sequencing using Illumina and Pacbio platforms, we have assembled high-quality genomes of the above two strains, with contig N50 reaching 4.2 and 1.7 Mbp, respectively, which is greater than those of published draft genomes. The genome data will provide a resource to assist research on the biological control mechanisms of Trichoderma spp.

Exonuclease I-assisted fluorescence aptasensor for tetrodotoxin.

A fluorescence aptasensor for the highly specific and sensitive determination of tetrodotoxin was established with tetrodotoxin-aptamer as the recognition unit, berberine as the signal reporter and exonuclease I as the elimination agent for the background. Berberine has a weak fluorescence emission at 540 nm, and it can form the tetrodotoxin-aptamer/berberine complex, resulted in an increased fluorescence. After introducing exonuclease I, it can degrade the single strand oligonucleotides of tetrodotoxin-aptamer into the single nucleotide in the absence of tetrodotoxin, which lead to dramatic fluorescence quenching, and reduce the background signal of sensing system. Once tetrodotoxin is in the presence, tetrodotoxin-aptamer is converted into the stable neck ring conformation, which resists the degradation of exonuclease I and provides a more rigid micro-environment for the excited state of berberine, and then the strong fluorescence is observed. Based on the above properties, an ultrasensitive label-free fluorescence aptasensor for tetrodotoxin is established. The fluorescence aptasensor shows good analytical performance with the linear increase of fluorescence intensity at the tetrodotoxin concentration from 0.030 nM to 6.0 × 103 nM. The detection limit of 11.0 pM is much lower than that of other reported sensor methods.

[Improved effect of comprehensive nutritional intervention of whole covering for Kazak's pregnant women, lactating women and infants in Altay farming and stockbreeding region].

OBJECTIVE: To study the effect of nutritional intervention for Kazak's pregnant women, lactating women and infants in farming and stockbreeding region of Jeminay County, Altay City. METHODS: 24 h record method was conducted to implement dietary survey, and results were used to analyze dietary structure and nutrient intake level of pregnant women, lactating women and infants. Pregnant women, lactating women and infants over 6 months were intervened with iron fortified soy sauce nutrients supplement and Yingyangbao(YYB) for 2. 4 years. Hemoglobin was detected for pregnant women, lactating women and infants by using HemoCue analyzer. RESULTS: The nutrient intakes of the pregnant women, lactating women and infants were averagely lower than that of the recommended levels. In these infants who received breast feeding, the least acceptability diet quality rate was 42. 1%, and in other infants who didn't receive breast feeding, the rate was 25%. After intervention, anemia prevalence of pregnant women, lactating women and infants were significantly reduced compared with the base line levels at 2 survey time points(2014:pregnant women χ~2=26. 27, lactating women χ~2=18. 06, infants χ~2=44. 46, 2015:pregnant women χ~2=35. 62, lactating women χ~2=25. 05, infants χ~2=39. 61;all P<0. 001). CONCLUSION: The nutrition intervention of whole covering could improve nutrition status of Kazak's pregnant women, lactating women and infants.

Trichoderma cyanodichotomus sp. nov., a new soil-inhabiting species with a potential for biological control.

During a biodiversity survey of Trichoderma (Ascomycota, Hypocreales, Hypocreaceae) in coastal and lake wetlands of China, a new species, Trichoderma cyanodichotomus, was isolated from Dongting Lake wetland of Hunan province. The strain TW21990-1 was characterized as having two types of conidia and producing a distinct blue-green pigment on potato dextrose agar and cornmeal dextrose agar. The taxonomic position was analyzed using three molecular markers, internal transcribed spacer rDNA, translation elongation factor 1-alpha, and RNA polymerase II subunit B, revealing less than 95.0% homology with all known Trichoderma species. The combined phylogenetic tree further identified T. cyanodichotomus as an independent subgroup belonging to Section Pachybasium, with no close relatives. In vitro antagonistic activity by dual-culture assay exhibited broad inhibition against various plant pathogens, including Botryosphaeria dothidea, Pythium aphanidermatum, Rhizoctonia solani, and Verticillium dahliae. In addition, TW21990-1 demonstrated moderate hydrolase activity of cellulase, chitinase, ß-1,3-glucanase, and protease, which might be involved in mycoparasitism. Greenhouse experiments showed strong biocontrol effects against tomato damping-off incited by P. aphanidermatum, together with increased seedling height and weight gain. The identification of T. cyanodichotomus will provide useful information for sufficient utilization of fungal resources.

Effect-Directed Analysis of Toxicants in Sediment with Combined Passive Dosing and in Vivo Toxicity Testing.

Identifying key toxicants in sediment is a great challenge, particularly if nontarget toxicants are involved. To identify the contaminants responsible for sediment toxicity to Chironomus dilutus in Guangzhou reach of the Pearl River in South China, passive dosing and in vivo toxicity testing were incorporated into effect-directed analysis (EDA) to account for bioavailability. Fractionation of sediment extracts was performed with gel permeation chromatography and reverse phase liquid chromatography sequentially. Polydimethylsiloxane served as passive dosing matrix for midge bioassays. The fractions showing abnormal enzymatic response were subject to a nontarget analysis, which screened out 15 candidate toxicants. The concentrations of the screened contaminants (log-based organic carbon normalized) in sediments of 10 sites were compared to sediment toxicity (10 and 20 day mortality and 10 day enzymatic response) to C. dilutus using correlation analyses. The results suggested that oxidative stress induced by cypermethrin, dimethomorph, pebulate and thenylchlor may have in part caused the observed toxicity to C. dilutus. The present study shows that EDA procedures coupled with passive dosing and in vivo toxicity testing can be effective in identifying sediment-bound toxicants, which may pose high risk to benthic organisms but are not routinely monitored and/or regulated. The findings of the present study highlight the importance of incorporating environmentally relevant approaches in assessing sediment heavily impacted by a multitude of contaminants, which is often the case in many developing countries.