288 research outputs found

    Cloning and Characterization of a Pyrethroid Pesticide Decomposing Esterase Gene, \u3cem\u3eEst3385\u3c/em\u3e, from \u3cem\u3eRhodopseudomonas palustris\u3c/em\u3e PSB-S

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    Full length open reading frame of pyrethroid detoxification gene, Est3385, contains 963 nucleotides. This gene was identified and cloned based on the genome sequence of Rhodopseudomonas palustris PSB-S available at the GneBank. The predicted amino acid sequence of Est3385 shared moderate identities (30–46%) with the known homologous esterases. Phylogenetic analysis revealed that Est3385 was a member in the esterase family I. Recombinant Est3385 was heterologous expressed in E. coli, purified and characterized for its substrate specificity, kinetics and stability under various conditions. The optimal temperature and pH for Est3385 were 35 °C and 6.0, respectively. This enzyme could detoxify various pyrethroid pesticides and degrade the optimal substrate fenpropathrin with a Km and Vmax value of 0.734 ± 0.013 mmol·l−1 and 0.918 ± 0.025 U·µg−1, respectively. No cofactor was found to affect Est3385 activity but substantial reduction of enzymatic activity was observed when metal ions were applied. Taken together, a new pyrethroid degradation esterase was identified and characterized. Modification of Est3385 with protein engineering toolsets should enhance its potential for field application to reduce the pesticide residue from agroecosystems

    Adrenalectomy for primary aldosteronism and its related surgical characteristics

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    Primary aldosteronism (PA) is a common cause of secondary hypertension. Adrenalectomy is an effective treatment for unilateral PA, particularly aldosterone-producing adenoma (APA), resulting in improvements in biochemical parameters and blood pressure in the vast majority of patients. The article provides a comprehensive overview of PA, focusing on the outcomes of adrenalectomy for PA and the factors that may suggest prognostic implications. Analysis of the outcome of different PA patients undergoing adrenalectomy in terms of preoperative factors, vascular and adipose conditions, type of pathology, and somatic variants. In addition, it is recommended to use the histopathology of primary aldosteronism (HISTALDO) consensus to classify the patient’s pathological type, with classical and nonclassical pathological types showing a different prognosis and possibly being associated with an unresected contralateral adrenal gland. The primary aldosteronism surgical outcome (PASO) consensus sets uniform standards for postoperative outcomes in unilateral PA, but its setting of thresholds remains controversial. Partial adrenalectomy shows similar surgical results and fewer postoperative complications than total adrenalectomy, but there is a risk of missing the true source of abnormal aldosterone secretion. Steroid profiling and functional imaging techniques offer alternative options to adrenal vein sampling (AVS) for unilateral and bilateral judgments in patients with PA. A combination of factors is needed to predict the prognosis of PA patients undergoing adrenalectomy in order to manage patient expectations of the outcome of the procedure and to closely monitor blood pressure and biochemical parameters in patients who suggest a poorer prognosis

    Selection of Reference Genes for RT-qPCR Analysis in a Predatory Biological Control Agent, \u3cem\u3eColeomegilla maculata\u3c/em\u3e (Coleoptera: Coccinellidae)

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    Reverse transcriptase-quantitative polymerase chain reaction (RT-qPCR) is a reliable technique for quantifying gene expression across various biological processes, of which requires a set of suited reference genes to normalize the expression data. Coleomegilla maculata (Coleoptera: Coccinellidae), is one of the most extensively used biological control agents in the field to manage arthropod pest species. In this study, expression profiles of 16 housekeeping genes selected from C. maculata were cloned and investigated. The performance of these candidates as endogenous controls under specific experimental conditions was evaluated by dedicated algorithms, including geNorm, Normfinder, BestKeeper, and ΔCt method. In addition, RefFinder, a comprehensive platform integrating all the above-mentioned algorithms, ranked the overall stability of these candidate genes. As a result, various sets of suitable reference genes were recommended specifically for experiments involving different tissues, developmental stages, sex, and C. maculate larvae treated with dietary double stranded RNA. This study represents the critical first step to establish a standardized RT-qPCR protocol for the functional genomics research in a ladybeetle C. maculate. Furthermore, it lays the foundation for conducting ecological risk assessment of RNAi-based gene silencing biotechnologies on non-target organisms; in this case, a key predatory biological control agent

    Detection and Epidemic Dynamic of ToCV and CCYV with \u3cem\u3eBemisia tabaci\u3c/em\u3e and Weed in Hainan of China

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    Background: In recent years, two of the crinivirus, Tomato chlorosis virus (ToCV) and Cucurbit chlorotic yellows virus (CCYV) have gained increasing attention due to their rapid spread and devastating impacts on vegetable production worldwide. Both of these viruses are transmitted by the sweet potato whitefly, Bemisia tabaci (Gennadius), in a semi-persistent manner. Up to now, there is still lack of report in Hainan, the south of China. Methods: We used observational and experimental methods to explore the prevalence and incidence dynamic of CCYV and ToCV transmitted by whiteflies in Hainan of China. Results: In 2016, the chlorosis symptom was observed in the tomato and cucumber plants with a large number of B. tabaci on the infected leaves in Hainan, China, with the incidence rate of 69.8% and 62.6% on tomato and cucumber, respectively. Based on molecular identification, Q biotype was determined with a viruliferous rate of 65.0% and 55.0% on the tomato and cucumber plants, respectively. The weed, Alternanthera philoxeroides near the tomato and cucumber was co-infected by the two viruses. Furthermore, incidence dynamic of ToCV and CCYV showed a close relationship with the weed, Alternanthera philoxeroides, which is widely distributed in Hainan. Conclusion: Our results firstly reveal that the weed, A. philoxeroides is infected by both ToCV and CCYV. Besides, whiteflies showed a high viruliferous rate of ToCV and CCYV. Hainan is an extremely important vegetable production and seed breeding center in China. If the whitefly can carry these two viruses concurrently, co-infection in their mutual host plants can lead to devastating losses in the near future

    Development of constrictional microchannels and the recurrent neural network in single-cell protein analysis

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    Introduction: As the golden approach of single-cell analysis, fluorescent flow cytometry can estimate single-cell proteins with high throughputs, which, however, cannot translate fluorescent intensities into protein numbers.Methods: This study reported a fluorescent flow cytometry based on constrictional microchannels for quantitative measurements of single-cell fluorescent levels and the recurrent neural network for data analysis of fluorescent profiles for high-accuracy cell-type classification.Results: As a demonstration, fluorescent profiles (e.g., FITC labeled β-actin antibody, PE labeled EpCAM antibody and PerCP labeled β-tubulin antibody) of individual A549 and CAL 27 cells were firstly measured and translated into protein numbers of 0.56 ± 0.43 × 104, 1.78 ± 1.06 × 106 and 8.11 ± 4.89 × 104 of A549 cells (ncell = 10232), and 3.47 ± 2.45 × 104, 2.65 ± 1.19 × 106 and 8.61 ± 5.25 × 104 of CAL 27 cells (ncell = 16376) based on the equivalent model of the constrictional microchannel. Then, the feedforward neural network was used to process these single-cell protein expressions, producing a classification accuracy of 92.0% for A549 vs. CAL 27 cells. In order to further increase the classification accuracies, as a key subtype of the recurrent neural network, the long short-term memory (LSTM) neural network was adopted to process fluorescent pulses sampled in constrictional microchannels directly, producing a classification accuracy of 95.5% for A549 vs. CAL 27 cells after optimization.Discussion: This fluorescent flow cytometry based on constrictional microchannels and recurrent neural network can function as an enabling tool of single-cell analysis and contribute to the development of quantitative cell biology

    Distribution pattern and influencing factors of in-situ stress for deep levels in Shoushan No.1 Coal Mine

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    To investigate the distribution pattern and influencing factors of in-situ stress for deep levels in the Shoushan No.1 Mine, according to the measured in-situ stress data of the mine, the tectonophysics and rock mechanics and numerical simulation methods were applied to study the type, magnitude and direction distribution pattern of in-situ stress. The distribution characteristics of in-situ stress field was simulated. The effect of buried depth, lithology and geological structure on the in-situ stress distribution was analyzed. The main factor of in-situ stress distribution was determined. The research shows that the in-situ stress values obtained by the multiple regression analysis of inversion method are consistent with the measured values. The relative error is less than 20% and the results are reliable. The coal and rock mass of mine is in a state of three-dimensional compressive stress. The principal stresses relation of coal seam is SH > SV > Sh. The in-situ stress increases firstly, then decreases and finally increases from the north to the south of the mine. The magnitude of in-situ stress is 28−44 MPa and belongs to the high stress level. The in-situ stress direction is NEE. The buried depth controls the magnitude and type distribution of the in-situ stress. With the increase of buried depth, the principal stress is increasing and the stress field type has the changing tendency from the dynamic stress field to quasi-hydrostatic pressure field. The lithology has a closely relationship with the in-situ stress. From mudstone to sandstone or limestone, the in-situ stress is increasing. The larger the elasticity module is, the higher the in-situ stress is. The difference of stratum lithology causes the discrete distribution of in-situ stress and the deflection angle of in-situ stress direction is less than 10°. The relation between the in-situ stress and the buried depth and the elasticity modulus is expressed as σH=0.0350H+0.4681E−8.5513 in the mine. The geological structure is the main controlling factor of in-situ stress in the mine. The fold shape controls the horizontal stress distribution of the in-situ stress. The in-situ stress of the syncline inner arc is more than that of the anticline inner arc. With the increase of the fold crook degree, the in-situ stress of inner arc increases gradually, and its stress gradient increases gradually. The in-situ stress of fault zone is decreasing and the in-situ stress of the fault pinch-out side is greater. The in-situ stress direction deflects along the fault strike. The larger the angle between maximum horizontal principal stress and the fault strike is, the greater deflection angle of maximum horizontal principal stress direction is. The in-situ stress of the tectonic association zone of fault and syncline is more than that of the tectonic association of fault and anticline. The tectonic association causes the undirectional distribution of the in-situ stress direction

    Aphid Performance Changes with Plant Defense Mediated by \u3cem\u3eCucumber mosaic virus\u3c/em\u3e Titer

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    Background: Cucumber mosaic virus (CMV) causes appreciable losses in vegetables, ornamentals and agricultural crops. The green peach aphid, Myzus persicae Sulzer (Aphididae) is one of the most efficient vectors for CMV. The transmission ecology of aphid-vectored CMV has been well investigated. However, the detailed description of the dynamic change in the plant-CMV-aphid interaction associated with plant defense and virus epidemics is not well known. Results: In this report, we investigated the relationship of virus titer with plant defense of salicylic acid (SA) and jasmonic acid (JA) during the different infection time and their interaction with aphids in CMV-infected tobacco plants. Our results showed that aphid performance changed with virus titer and plant defense on CMV-inoculated plants. At first, plant defense was low and aphid number increased gradually. The plant defense of SA signaling pathway was induced when virus titer was at a high level, and aphid performance was correspondingly reduced. Additionally, the winged aphids were increased. Conclusion: Our results showed that aphid performance was reduced due to the induced plant defense mediated by Cucumber mosaic virus titer. Additionally, some wingless aphids became to winged aphids. In this way CMV could be transmitted with the migration of winged aphids. We should take measures to prevent aphids in the early stage of their occurrence in the field to prevent virus outbreak
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