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BACKGROUND: Bursaphelenchus xylophilus, the causative agent of pine wilt disease (PWD), is an ever-increasing threat to Pinus forests worldwide. This study aimed to develop biological control of PWD by the application of endophytic fungi isolated from healthy pine trees. RESULTS: We successfully isolated a novel endophytic fungal strain 1-24-2 from branches of healthy Pinus massoniana. The culture filtrates (CFs) of strain 1-24-2 exhibited strong nematicidal activity against Bursaphelenchus xylophilus, with a corrected mortality rate of 99.00%. Based on the morphological and molecular characteristics, the isolated strain 1-24-2 was identified as Chaetomium ascotrichoides. In the in-planta assay, pine seedlings (2-years-old) treated with 1-24-2 CFs + pine wood nematode (T2) showed a significant control effect of 80%. A total of 24 toxic compounds were first identified from 1-24-2 CFs through gas chromatography-mass spectrometry (GC-MS) analysis, from which O-methylisourea, 2-chlorobenzothiazole, and 4,5,6-trihydroxy-7-methylphthalide showed robust binding sites at Tyr119 against phosphoethanolamine methyltransferase (PMT) protein of Bursaphelenchus xylophilus by molecular docking approach and could be used as potential compounds for developing effective nematicides. Interestingly, strain 1-24-2 produces toxic volatile organic compounds (VOCs), which disturb the natural development process of B. xylophilus, whose total number decreased by up to 83.32% in the treatment group as compared to control and also reduced Botrytis cinerea growth by up to 71.01%. CONCLUSION: Our results highlight the potential of C. ascotrichoides 1-24-2 as a promising biocontrol agent with solid nematicidal activity against B. xylophilus. This is the first report of C. ascotrichoides isolated from P. massoniana exhibiting strong biocontrol potential against B. xylophilus in the world. © 2024 Society of Chemical Industry.
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Introduction: Straw return has been widely recognized as an important carbon (C) enhancement measure in agroecosystems, but the C-phosphorus (P) interactions and their effects on plants in saline soils are still unclear. Methods: In this study, we investigated the effects of straw return and three P application levels, no P fertilizer (Non-P), a conventional application rate of P fertilizer (CP), and a high application rate of P fertilizer (HP), on maize growth and soil C and P fractions through a pot experiment. Results and discussion: The results revealed that the dry matter weight of maize plant was no difference between the two straw return levels and was 15.36% higher under HP treatments than under Non-P treatments. Plant nutrient accumulations were enhanced by straw addition and increased with increasing P application rate. Straw application reduced the activities of peroxidase (POD), superoxide dismutase (SOD), catalase, and the content of malondialdehyde (MDA) in maize plants by 31.69%, 38.99%, 45.96% and 27.04%, respectively. P application decreased SOD, POD activities and MDA content in the absence of straw. The contents of easily oxidized organic carbon (EOC), particulate organic carbon (POC) and the ratio of POC/SOC in straw-added soils were 10.23%, 17.00% and 7.27% higher, respectively, than those in straw-absent soils. Compared with Non-P treatments, HP treatments led to an increase of 12.05%, 23.04% in EOC, POC contents respectively, while a decrease of 18.12% in the contribution of MAOC to the SOC pool. Straw return improved the P status of the saline soil by increasing soil available P (14.80%), organic P (35.91%) and Ca2-P contents (4.68%). The structural equation model showed that straw and P applications could promote maize growth (indicated by dry matter weight, P accumulation, antioxidant enzyme activity and MDA content) through improving soil C and P availabilities. Conclusion: This study provides evidence that straw return together with adequate P supply in saline soil can promote crop nutrient accumulation, attenuate the oxidation damage on crop growth, and be beneficial for SOC turnover and soil P activation.
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With their wide application in industrial fields, the denoising and/or filtering of line-scan images is becoming more important, which also affects the quality of their subsequent recognition or classification. Based on the application of single source dual-energy X-ray transmission (DE-XRT) line-scan in-line material sorting and the different horizontal and vertical characteristics of line-scan images, an improved adaptive Kalman-median filter (IAKMF) was proposed for several kinds of noises of an energy integral detector. The filter was realized through the determination of the off-line noise total covariance, the covariance distribution coefficient between the process noise and measurement noise, the adaptive covariance scale coefficient, calculation scanning mode and single line median filter. The experimental results show that the proposed filter has the advantages of simple code, good real-time control, high precision, small artifacts, convenience and practicality. It can take into account the filtering of high-frequency random noise, the retention of low-frequency real signal fluctuation and the preservation of shape features. The filter also has a good practical application value and can be improved and extended to other line-scan image filtering scenarios.
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BACKGROUND Sodium salicylate (SS) induces excitotoxicity of spiral ganglion neurons (SGNs) by inhibiting the response of γ-aminobutyric acid type A receptors (GABAARs). Our previous studies have shown that SS can increase the internalization of GABAARs on SGNs, which involves dopamine D1-like receptors (D1Rs) and related signaling pathways. In this study, we aimed to explore the role of D1Rs and their downstream molecule protein kinase C (PKC) in the process of SS inhibiting GABAARs. MATERIAL AND METHODS The expression of D1Rs and GABARγ2 on rat cochlear SGNs cultured in vitro was tested by immunofluorescence. Then, the SGNs were exposed to SS, D1R agonist (SKF38393), D1R antagonist (SCH23390), clathrin/dynamin-mediated endocytosis inhibitor (dynasore), and PKC inhibitor (Bisindolylmaleimide I). Western blotting and whole-cell patch clamp technique were used to assess the changes of surface and total protein of GABARγ2 and GABA-activated currents. RESULTS Immunofluorescence showed that D1 receptors (DRD1) were expressed on SGNs. Data from western blotting showed that SS promoted the internalization of cell surface GABAARs, and activating D1Rs had the same result. Inhibiting D1Rs and PKC decreased the internalization of GABAARs. Meanwhile, the phosphorylation level of GABAARγ2 S327 affected by PKC was positively correlated with the degree of internalization of GABAARs. Moreover, whole-cell patch clamp recording showed that inhibition of D1Rs or co-inhibition of D1Rs and PKC attenuated the inhibitory effect of SS on GABA-activated currents. CONCLUSIONS D1Rs mediate the GABAAR internalization induced by SS via a PKC-dependent manner and participate in the excitotoxic process of SGNs.
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Ototoxicité/anatomopathologie , Protéine kinase C/métabolisme , Récepteur dopamine D1/métabolisme , Récepteurs GABA-A/métabolisme , Salicylate de sodium/effets indésirables , Ganglion spiral/anatomopathologie , 1-Phényl-2,3,4,5-tétrahydro-1H-3-benzazépine-7,8-diol/pharmacologie , Animaux , Benzazépines , Cellules cultivées , Modèles animaux de maladie humaine , Femelle , Humains , Hydrazones/pharmacologie , Mâle , Modèles animaux , Neurones/effets des médicaments et des substances chimiques , Neurones/métabolisme , Ototoxicité/étiologie , Techniques de patch-clamp , Culture de cellules primaires , Rats , Récepteur dopamine D1/agonistes , Récepteur dopamine D1/antagonistes et inhibiteurs , Ganglion spiral/cytologie , Ganglion spiral/effets des médicaments et des substances chimiquesRÉSUMÉ
The validity of theoretical investigation on Rayleigh-Taylor instability (RTI) with nonlinearity is quite important, especially for the simplest and the commonest case of a pure single-mode RTI, while its previous explicit solution in weakly nonlinear scheme is found to have several defections. In this paper, this RTI is strictly solved by the method of the potential functions up to the third order at the weakly nonlinear stage for arbitrary Atwood numbers. It is found that the potential solution includes terms of both the stimulating and inhibiting RTI, while the terms of the decreasing RTI are omitted in the classical solution of the weakly nonlinear scheme, resulting in a big difference between these two results. For the pure single-mode cosine perturbation, comparisons among the classical result, the present potential result and numerical simulations, in which the two dimensional Euler equations are used, are carefully performed. Our result is in a better agreement with the numerical simulations than the classical one before the saturation time. To avoid the tedious expressions and improve a larger valid range of the solution, the method of the Taylor expansion is employed and the velocities of the bubble and spike are, respectively, obtained. Comparisons between the improved and the simulation results show that the improved theory can better predict the evolution of the interface from the linear to weakly nonlinear, even to later of the nonlinear stages.
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The purpose of this study was to observe the regulatory effects of GABAA (γ-aminobutyric acid A) receptor on the N-methyl-D-aspartate (NMDA) receptor during excitotoxicity in spiral ganglion neurons in the rat cochlea induced by sodium salicylate (SS). Western blot illustrated SS decreased the expression of NMDA receptor 2B subunit (NR2B) surface protein through affecting GABAA receptor, but the total protein content did not significantly change. Y1472 and S1480 are important phosphorylation sites in NR2B, SS downregulated the Fyn-dependent phosphorylation of Y1472 in a manner not related to the CK2 (Casein Kinase 2) dependent phosphorylation of S1480, thus regulating the surface distribution and internalization of NMDA receptor through GABAA receptor. These results suggest that the modified pattern of dynamic balance between excitation and inhibition by coactivation of the GABAA receptor can attenuate the excitatory NMDA receptor under the action of SS, via inhibiting the Fyn-dependent phosphorylation of Y1472.
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Anti-inflammatoires non stéroïdiens/toxicité , Récepteurs GABA-A/métabolisme , Récepteurs du N-méthyl-D-aspartate/métabolisme , Salicylate de sodium/toxicité , Ganglion spiral/effets des médicaments et des substances chimiques , Animaux , Neurones/effets des médicaments et des substances chimiques , Neurones/métabolisme , Syndromes neurotoxiques/étiologie , Syndromes neurotoxiques/métabolisme , Phosphorylation/effets des médicaments et des substances chimiques , Protéines proto-oncogènes c-fyn/métabolisme , Rats , Rat Sprague-Dawley , Ganglion spiral/métabolismeRÉSUMÉ
Sodium salicylate (SS) is one of the nonsteroidal anti-inflammatory drugs and widely used in clinical practice. Therefore, we aimed to investigate the potential ototoxicity mechanism of sodium salicylate: the influence of Ca2+/calmodulin-dependent protein kinase II (Ca2+/CaMKII) in interaction between NMDA receptors (NMDAR) and GABAA receptors (GABAAR) in rat cochlear spiral ganglion neurons (SGNs). After treatment with SS, NMDA, and an NMDAR inhibitor (APV), the changes of GABAAR ß3 (GABR ß3) mRNA, surface and total protein, and GABAAR currents in SGNs were assessed by quantitative PCR, Western blot, and whole-cell patch clamp. Mechanistically, SS and/or NMDA increased the GABR ß3 mRNA expression, while decreased GABR ß3 surface protein levels and GABAAR-mediated currents. Moreover, application of SS and/or NMDA showed promotion in phosphorylation levels at S383 of GABR ß3. Collectively, Ca2+ chelator (BAPTA) or Ca2+/CaMKII inhibitor (KN-93) reversed the effects of SS and/or NMDA on GABAAR. Therefore, we hypothesize that the interaction between NMDAR and GABAAR is involved in the SGNs damage induced by SS. In addition, the underlying molecular mechanism is related to Ca2+/CaMKII-mediated signaling pathway, which suggests that the interaction between calcium signal-regulated receptors mediates SS ototoxicity.
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Anti-inflammatoires non stéroïdiens/toxicité , Calcium-Calmodulin-Dependent Protein Kinase Type 2/métabolisme , Neurones/effets des médicaments et des substances chimiques , Récepteurs GABA-A/métabolisme , Récepteurs du N-méthyl-D-aspartate/métabolisme , Salicylate de sodium/toxicité , Ganglion spiral/effets des médicaments et des substances chimiques , Animaux , Neurones/métabolisme , Rat Sprague-Dawley , Ganglion spiral/métabolismeRÉSUMÉ
Consistent descriptions of the equation of states and information about the transport coefficients of the deuterium-tritium mixture are demonstrated through quantum molecular dynamic (QMD) simulations (up to a density of 600 g/cm(3) and a temperature of 10(4) eV). Diffusion coefficients and viscosity are compared to the one-component plasma model in different regimes from the strong coupled to the kinetic one. Electronic and radiative transport coefficients, which are compared to models currently used in hydrodynamic simulations of inertial confinement fusion, are evaluated up to 800 eV. The Lorentz number is discussed from the highly degenerate to the intermediate region. One-dimensional hydrodynamic simulation results indicate that different temperature and density distributions are observed during the target implosion process by using the Spitzer model and ab initio transport coefficients.
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OBJECTIVE: To investigate the metabolic profile of hydrocortisone-induced 'Kidney-yang deficiency syndrome'in rats and the intervention effects of Morinda officinalis. METHOD: Proton nuclear magnetic resonance (1H-NMR) technique was used to analyze the rat metabonome in serum. Orthogonal partial least squares discriminant analysis (OPLS-DA) were processed to analyze the metabonome difference between the control and hydrocortisone treated samples. Twelve potential biomarkers were selected, via the parameter of variable importance in the projection (VIP). Principal components analysis (PCA) was employed to process the data from the M. officinalis. treatment group and the intervention effects of M. officinalis, was investigated through the selected potential biomarkers. RESULT: After hydrocortisone treatment, the energy metabolism, amino acids metabolism and gut microflora environment were seriously disturbed and transmethylation was surpressed. M. officinalis could effectively alleviate the disturbance of energy and amino acids metabolism and enhance transmethylation, but could not modulate the gut microflora environment. CONCLUSION: The results obtained suggested that metabonomic studies could better reflect the whole status of metabolism in bio-systems, and could be treated as a potential powerful approach in pharmacological studies and investigation of the essence of 'syndrome' in traditional Chinese medicine.
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Médicaments issus de plantes chinoises/pharmacologie , Rein/effets des médicaments et des substances chimiques , Rein/métabolisme , Métabolomique , Morinda/composition chimique , Déficit du Yang/traitement médicamenteux , Déficit du Yang/métabolisme , Animaux , Marqueurs biologiques/métabolisme , Médicaments issus de plantes chinoises/usage thérapeutique , Mâle , Rats , Rat Sprague-DawleyRÉSUMÉ
OBJECTIVE: To investigate the characteristic of NK cells and NKT cells in HBV infected pediatric subjects for evaluation of their clinical implication. METHODS: Fresh peripheral blood samples were obtained from 42 HBV-infected pediatric cases and 15 healthy counterparts. NK cells and NKT cells were analyzed by flow cytometry assay. The clinical data such as serum ALT level and HBV viral load was simultaneously recorded from each HBV carrier. RESULTS: HBV-infected children had an obviously increasing percentage of NK cells 12.071% +/- 7.100%, there were significant differences between the children with chronic B hepatitis and the healthy children (P <0.05). As far as percentage of NKT 3.048% +/- 1.937% was concerned, there were not differences. Furthermore the association was not found between serum HBV viral load level and the NK lymphocyte. CONCLUSION: Our data may provide valuable information of NK and NKT lymphocyte for evaluation of disease progression of HBV infected children NKI cells.
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Virus de l'hépatite B/physiologie , Hépatite B chronique/immunologie , Cellules tueuses naturelles/immunologie , Cellules T tueuses naturelles/immunologie , Adolescent , Cellules cultivées , Enfant , Femelle , Virus de l'hépatite B/immunologie , Hépatite B chronique/virologie , Humains , MâleRÉSUMÉ
OBJECTIVE: To study the clinical, laboratory, and radiologic features of 34 cases of severe acute respiratory syndrome (SARS) in Beijing. METHODS: All patients were admitted to the isolation wards. Their demographic, clinical, laboratory, and radiologic characteristics were analyzed. Univariate and multivariate analyses were performed. RESULTS: Eight patients came from a family, and 15 patients were medical staff. The mean age of patients was (33.4 +/- 13.4) years. The latent period varied from 2 to 14 days (median 4 days). The most common symptoms were fever (100%), palpitation (91.7%), myalgia (79.2%), headache (70.8%), diarrhea (73.9%) and cough (58.3%). The mean leucocyte count was (4.6 +/- 1.4) x 10(9)/L, and the mean lymphocyte ratio was 0.27 +/- 0.11. 68.4% of the patients had lymphopenia (absolute lymphocyte count < 1.3 x 10(9)/L). Other common findings included elevated levels of serum alanine aminotransferase, lactate dehydrogenase and erythrocyte sedimentation (76.2%, 28.6% and 47.8%, respectively), and decreased levels of serum iron and albumin (63.2% and 47.8%, respectively). Thirty-two cases had abnormal chest radiographs. In 2 cases in whom typical lung opacities could not be found on the initial plain chest radiographs, thoracic CT proved to be useful. Postmortem examination of 1 patient revealed marked edema with foci of hemorrhage and hyaline membrane formation in the lungs, hemorrhage necrosis and a obvious decline of cells in lymph glands. In a multivariate analysis (Stata 7.0), the independent predictor of an adverse outcome was advanced age (odds ratio per decade of life, 1.6; 95% CI, 1.08 to 2.63; P = 0.007). CONCLUSIONS: Fever, lymphopenia, low serum iron and chest radiograph are helpful to diagnose SARS early; age is the independent predictor of an outcome.
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Syndrome respiratoire aigu sévère/diagnostic , Adulte , Facteurs âges , Sujet âgé , Chine , Diagnostic précoce , Femelle , Fièvre/diagnostic , Humains , Fer/sang , Numération des lymphocytes , Mâle , Adulte d'âge moyen , Pronostic , Radiographie thoraciqueRÉSUMÉ
OBJECTIVE: To compare the antibacterial effects of Huangqin-Tang with its metabolites produced by intestinal flora. METHOD: The antibacterial tests in vitro and in vivo were performed by agar dilution method and lethal protection of animal respectively. RESULT: Huangqin-Tang and its metabolites had antibacterial action on bacteria in vitro, however the antibacterial activity of metabolites of Huangqin-Tang on Salmomella, Dysentery bacillus and Proteus in vitro was stronger than Huangqin-Tang. The metabolites of Huangqin-Tang had protective effect on the animals infected by Staphylococcus aureus and Escherichia coli respectively from death, but Huangqin-Tang had no lethal protection action. CONCLUSION: The antibacterial effects of metabolites of Huangqin-Tang in vitro and in vivo are stronger than that of Huangqin-Tang, which shows that intestinal flora play a very important role in antibacterial effects of Huangqin-Tang.
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Antibactériens/pharmacologie , Médicaments issus de plantes chinoises/pharmacologie , Intestins/microbiologie , Salmonella/effets des médicaments et des substances chimiques , Infections à staphylocoques/traitement médicamenteux , Animaux , Antibactériens/usage thérapeutique , Médicaments issus de plantes chinoises/usage thérapeutique , Infections à Escherichia coli/traitement médicamenteux , Fèces/microbiologie , Mâle , Souris , Phytothérapie , Plantes médicinales/composition chimique , Proteus/effets des médicaments et des substances chimiques , Shigella dysenteriae/effets des médicaments et des substances chimiquesRÉSUMÉ
OBJECTIVE: To compare the protective activity of liver injury induced by D-galactosamine (GalN) between Huangqin-Tang and their metabolites by human intestinal bacteria(HIB). METHOD: The liver injuries in conventional and pseudo-germfree mice were induced by GalN. After oral administration of Huangqin-Tang and their metabolites mixtures by HIB, the serum transaminase (ALT and AST) activities were detected. RESULT: In conventional mice, large and medium doses (20 and 10 g.kg-1) of Huangqin-Tang decoction significantly reduced the increase of serum ALT activity after 18 h GalN treatment. In pseudo-germfree mice, metabolites significantly reduced the ALT levels. However, Huangqing-Tang didn't affect the ALT levels in this kind of mice. To all of the animals, AST levels remained the same after oral Huangqin-tang or their metabolites. CONCLUSION: The metabolism by intestinal bacteria plays a role in pharmacological effects of constituents of Chinese herbal medicine. The metabolites of the constituents by intestinal bacteria were the real active components in vivo.
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Médicaments issus de plantes chinoises/pharmacologie , Intestins/microbiologie , Maladies du foie/métabolisme , Agents protecteurs/pharmacologie , Administration par voie orale , Alanine transaminase/sang , Animaux , Aspartate aminotransferases/sang , Bactéries/métabolisme , Lésions hépatiques dues aux substances , Médicaments issus de plantes chinoises/isolement et purification , Médicaments issus de plantes chinoises/métabolisme , Galactosamine , Mâle , Souris , Plantes médicinales/composition chimique , Agents protecteurs/métabolismeRÉSUMÉ
Recent experiment [S.G. Glendinning et al., Phys. Rev. Lett. 78, 3318 (1997)] showed that the measured growth rate of laser ablative Rayleigh-Taylor (RT) instability with preheating is about 50% of the classic value and is reduced by about 18% compared with the simulated value obtained with the computer code LASNEX. By changing the temperature variation of the electron thermal conductivity at low temperatures, the density profile from the Bhatnagar-Gross-Krook approximation is recovered in the simulation, and the simulated RT growth rate is in good agreement with the experimental value from Glendinning et al. The preheated density profile on ablative RT stablization is studied numerically. A change of the Atwood number in the preheating case also leads to RT stabilization. The RT growth formula gamma=square root of [Akg/(1+AkL)] - 2kV(a) agrees well with experiment and simulation, and is appropriate for the preheating case.
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In the course of studies on the metabolism of active components of Huangqin-Tang by human intestinal flora (HIF), Huangqin-Tang and all individual herbs in the decoctions were incubated with a human fecal suspension separately. By using a high-performance liquid chromatographic (HPLC) method which was previously established in our laboratory, the metabolites in both the compound prescription and all the single herb decoctions were identified and determined both qualitatively and quantitatively. We found that the constituents of Huangqin-Tang, incluing baicalin (baicalein 7-glucuronide; BG), wogonoside (wogoninoglucuronide; WG), oroxylin-A-glucuronide (OG) from Scutellariae Radix, paeoniflorin (PF) from Paeoniae Radix, liquiritin (liquiritigenin 4'-O-glucoside; LG), isoliquirtin (isoliquiritigenin 4-glucoside; ILG) and glycyrrhizic acid (GL) from Glycyhhizea Radix, were converted to their metabolites baicalein (B), wogonin (W), oroxylin-A (O), paeonimetabolin-I (PM-I), liquiritigenin (L), isoliquiritigenin (IL) and glycyrrhetinic acid (GA) by HIF. The contents of the metabolites in Huangqin-Tang and in each single herb decoction increased significantly after incubation with intestinal flora. Comparing with single herb decoctions, the transformation of BG, WG, OG, LG and ILG in the compound prescription was promoted, however, that of PF and GL was inhibited. All the results suggested that the glycosides of many medicinal herbs could be converted to aglycones by HIF, and the metabolism of most glycosides was improved in the compound prescription.