Fe3O4 coated stent prevent artery neointimal hyperplasia by inhibiting vascular smooth muscle cell proliferation.

In-stent restenosis (ISR), caused by aggressive vascular smooth muscle cell (VSMC) proliferation, is a serious complication of stenting. Therefore, developing therapeutic approaches that target VSMC inhibition is imperative. Our previous study showed that VSMC hyperplasia was attenuated after iron stent degradation, and VSMC proliferation around the stented section was arrested. The corrosion products of the iron stents were primarily Fe3O4 particles. Therefore, we hypothesized that Fe3O4 particles generated by iron stents would prevent neointimal hyperplasia by inhibiting VSMC proliferation. To test this hypothesis, culture assays and flow cytometry were performed to investigate the proliferation of VSMC. Global gene sequencing and Kyoto Encyclopedia of Genes and Genomes enrichment analyses were performed to investigate the underlying mechanisms. Fe3O4-coated stents were implanted into rabbit carotid arteries to evaluate the inhibitory effects of Fe3O4 on neointimal hyperplasia. The major findings of the study were as follows: 1) Fe3O4 attenuated neointimal hyperplasia by preventing VSMC proliferation after stenting; 2) Fe3O4 exerted inhibitory effects on VSMCs by downregulating proliferative genes such as SOX9, EGR4, and TGFB1, but upregulated inhibitory genes such as DNMT1, TIMP3, and PCNA; 3) Fe3O4 inhibited VSMCs by preventing phenotypic transformation from the contractile to the synthetic phase; and 4) Fe3O4-coated stents achieved satisfactory hemocompatibility in a rabbit model. Our study highlights the additional benefits of Fe3O4 particles in inhibiting VSMC proliferation, indicating that Fe3O4 coated stent potentially served as an attractive therapeutic approach for ISR prevention.

Organic fertilizer substitution benefits microbial richness and wheat yield under warming.

Climate warming poses a serious threat to soil biodiversity and crop yield. Application of organic fertilizer has been extensively practiced to improve soil health and crop productivity. However, information is limited about the effects of organic fertilizer on microbial communities and diversity (richness) under warming. Thus, to investigate the interactive effects of temperature (ambient temperature and warming) and fertilizer (chemical fertilizer and partial substitution of chemical fertilizer with organic fertilizer) on microbial properties and wheat yield, a two-factorial pot experiment was conducted using soils with high and low fertility The results showed that warming and organic fertilizer had minor effects on bacterial Shannon and Simpson indexes. Due to concomitant reductions in soil moisture, warming decreased the average Chao index by 5.4 % and Ace index by 3.8 % for soils with high and low fertility (P < 0.05). High-throughput sequence presented that dominated genus was Bacillus with spore-forming ability. Under warming and drying conditions, microbes with adaptive traits (spore-forming ability) would outcompete the other microbes, and decrease microbial Chao and Ace index (richness). However, organic fertilizer counteracted the adverse effects of warming on microbial richness attributed to positive interaction between temperature and fertilizer on soil nutrients and organic carbon. The strong relationships between bacterial richness and wheat yield, as well as soil nutrients, highlighted the importance of soil biodiversity in improving soil nutrients and crop productivity. Partial substitution of chemical fertilizer with organic fertilizer significantly increased wheat yield by 27.1 % and 14.9 % under ambient temperature and by 28.0 % and 19.6 % under warming for soils with high and low fertility, respectively. Overall, this study provided the possibility to increase bacterial richness related to nutrient turnover and crop production by organic fertilizer application with reduced chemical fertilizer, especially under climate warming.

Early Identification of Rotten Potatoes Using an Electronic Nose Based on Feature Discretization and Ensemble Convolutional Neural Network.

The early identification of rotten potatoes is one of the most important challenges in a storage facility because of the inconspicuous symptoms of rot, the high density of storage, and environmental factors (such as temperature, humidity, and ambient gases). An electronic nose system based on an ensemble convolutional neural network (ECNN, a powerful feature extraction method) was developed to detect potatoes with different degrees of rot. Three types of potatoes were detected: normal samples, slightly rotten samples, and totally rotten samples. A feature discretization method was proposed to optimize the impact of ambient gases on electronic nose signals by eliminating redundant information from the features. The ECNN based on original features presented good results for the prediction of rotten potatoes in both laboratory and storage environments, and the accuracy of the prediction results was 94.70% and 90.76%, respectively. Moreover, the application of the feature discretization method significantly improved the prediction results, and the accuracy of prediction results improved by 1.59% and 3.73%, respectively. Above all, the electronic nose system performed well in the identification of three types of potatoes by using the ECNN, and the proposed feature discretization method was helpful in reducing the interference of ambient gases.

Vanadium Metal Doping of Monolayer MoS2 for p-Type Transistors and Fast-Speed Phototransistors.

Modulating the electrical properties of two-dimensional (2D) materials is a fundamental prerequisite for their development to advanced electronic and optoelectronic devices. Substitutional doping has been demonstrated as an effective method for tuning the band structure in monolayer 2D materials. Here, we demonstrate a facile selective-area growth of vanadium-doped molybdenum disulfide (V-doped MoS2) flakes via pre-patterned vanadium-metal-assisted chemical vapor deposition (CVD). Optical microscopy characterization revealed the presence of flake arrays. Transmission electron microscopy, Raman spectroscopy, and X-ray photoelectron spectroscopy were employed to identify the chemical composition and crystalline structure of as-grown flakes. Electrical measurements indicated a light p-type conduction behavior in monolayer V-doped MoS2. Furthermore, the response time of phototransistors based on V-doped MoS2 monolayers exhibited a remarkable capability of 3 ms, representing approximately 3 orders of magnitude faster response than that observed in pure MoS2 phototransistors. This work hereby provides a feasible approach to doping of 2D materials, promising a scalable pathway for the integration of these materials into emerging electronic and optoelectronic devices.

Research on detection of potato varieties based on spectral imaging analytical algorithm.

Potatoes are popular among consumers due to their high yield and delicious taste. However, due to the numerous varieties of potatoes, different varieties are suitable for different processing methods. Therefore, it is necessary to distinguish varieties after harvest to meet the needs of processing enterprises and consumers. In this study, a new visible-near-infrared spectroscopic analysis method was proposed, which can achieve detection of five potato varieties. The method measures the transmission and reflection spectra of potatoes using a spectral acquisition system, encodes one-dimensional spectra into two-dimensional images using Gramian Angular Summation Field (GASF), Gramian Angular Difference Field (GADF), Markov Transition Field (MTF) and Recurrence Plot (RP), and improves the coordinated attention mechanism module and embeds the improved module into the ConvNeXt V2 model to build the ConvNeXt V2-CAP model for potato variety classification. The results show that compared with directly using one-dimensional classification models, image encoding of spectral data for classification greatly improves the accuracy. Among them, the best accuracy of 99.54% is achieved by using GADF image encoding of transmission spectra combined with the ConvNeXt V2-CAP model for classification, which is 16.28% higher than the highest accuracy of the one-dimensional classification model. The CAP attention mechanism module improves the performance of the model, especially when the dataset is small. When the training set is reduced to 150 images, the accuracy of the model is improved by 2.33% compared to the original model. Therefore, it is feasible to classify potato varieties using visible-near infrared spectroscopy and image encoding technology.

Diabetic conditions promote drug coating degradation but prevent endothelial coverage after stenting.

The endothelialization of drug-eluting stents is delayed after implantation in patients with diabetes. Although numerous factors were implicated in hyperglycemia-induced endothelial dysfunction, the effects of stent drug coating degradation on endothelial dysfunction remains unclear. We hypothesized that diabetic conditions promote drugcoating degradation and enhance antiproliferative agent release, but that the rapid release of these antiproliferative agents inhibits endothelial cell proliferation leading to poor reendothelialization post-stenting. To verify this hypothesis, a dynamic hyperglycemic circulation system was introduced to measure the profile of drugcoating degradation in vitro. Flow cytometry and RNA sequencing were performed to evaluate endothelial cell proliferation. Moreover, a Type 1 diabetic rabbit model was generated and a rescue experiment conducted to evaluate the effects of rapid drugcoating elution on endothelial coverage in vivo. The main findings were as follows: 1) diabetic conditions promoted drugcoating degradation and increased antiproliferative agent release; 2) this increase in antiproliferative agent release inhibited endothelial cell proliferation and delayed endothelial coverage; and 3) strict glycemic control attenuated drugcoating degradation and promoted endothelial coverage post-stenting. This is the first study to illustrate rapid drugcoating degradation and its potential effects on endothelial recovery under diabetic conditions, highlighting the importance of strict glycemic management in patients with diabetes after drug-eluting stent implantation. STATEMENT OF SIGNIFICANCE: Diabetic conditions promote drug coating degradation and increase the release of antiproliferative agents. Rapid drug coating degradation under diabetic conditions inhibits endothelial cell proliferation and delays endothelialization. Strict glycemic control attenuates drug coating degradation and promotes endothelialization.

Low-threshold AlGaN-based deep ultraviolet laser enabled by a nanoporous cladding layer.

We demonstrated an AlGaN-based multiple-quantum-well (MQW) deep ultraviolet (DUV) laser at 278 nm using a nanoporous (NP) n-AlGaN as the bottom cladding layer grown on the sapphire substrate. The laser has a very-low-threshold optically pumped power density of 79 kW/cm2 at room temperature and a transverse electric (TE)-polarization-dominant emission. The high optical confinement factor of 9.12% benefiting from the low refractive index of the nanoporous n-AlGaN is the key to enable a low-threshold lasing. The I-V electrical measurement demonstrates that an ohmic contact can be still achieved in the NP n-AlGaN with a larger but acceptable resistance, which indicates it is compatible with electrically driven laser devices. Our work provides insights into the design and fabrication of low-threshold lasers emitting in the DUV regime.

Origin of Water-Stable CsPbX3 Quantum Dots Assisted by Zwitterionic Ligands and Sequential Strategies for Enhanced Luminescence Based on Crystal Evolution.

Water stability is a crucial issue always addressed for commercial practical application of perovskite quantum dots (QDs). Recent advances in ligand engineering for in situ synthesis of water-stable perovskite QDs have attracted growing interest. However, the exact mechanism remains unclear. Here, the function of 4-bromobutyric acid (BBA) and oleylamine (OLA) is systematically studied in water-stable CsPbX3 (X = Br and I) QDs and confirms that the zwitterionic ligands generated in situ by BBA and OLA are anchored on the QDs surface, thus preventing water from penetrating into the QDs. Cs4PbBr6 intermediate crystal found in the crystal structure evolution process of CsPbX3 QD further reveals a complete crystallization process: PbX2 + CsX + Br- → Cs4PbBr6 crystals + X-→ CsPbX3 QDs + Br-. Furthermore, it is found that the solvent coordination of the precursor solution has a significant effect on the crystallinity of Cs4PbBr6 intermediate crystal, while the Rb+ doping can effectively passivate the surface defects of CsPbX3 QDs, thereby jointly achieving photoluminescence quantum yields (PLQY) of 94.6% for CsPbBr3 QDs (88.2% for CsPbI3 QDs). This work provides new insights and guiding ideas for the green synthesis of high-quality and water-stable perovskite QDs.

Effects of long-term different-scale rice-duck farming on the growth and yield of paddy rice.

BACKGROUND: To maintain rice production and increase revenue, rice-duck (RD) farming is a contemporary ecological cycle technology that has been widely used in Asia. However, due to the clustering activity of duck flocks, the consequences of long-term RD farming on rice growth at different scales are still unknown. Here, we studied RD farming using several different treatments (CK: conventional rice farming; RD1: 667 m2 ; RD2: 2000 m2 ; and RD3: 3333 m2 ). RESULTS: The results demonstrated that the maximum tillers, effective spikes, dry matter accumulation, and lodging index of rice under RD farming were significantly decreased by 17.9%, 9.8%, 14.8%, and 17.8%, respectively, which ultimately caused a significant decrease in yield of 10.6%. However, RD farming significantly increased root oxidation activity and the ear-bearing tiller rate of rice by 25.5% and 11.1%, respectively, and improved yield stability. For different scales of RD farming, the lodging resistance index of RD1 was significantly lower than that of RD2 and RD3 by 10.0% and 15.2%, respectively, whereas the root oxidation activity and dry matter accumulation of RD2 were significantly higher than those of RD1 and RD3 by 11.1%, 4.7%, 8.6%, and 5.1%, respectively. For rice yield, there was no significant difference among the different scales. CONCLUSION: This long-term experiment helped elucidate the complicated effects of RD farming at different scales on the growth and yield of rice. It is also critical to consider the economic advantages of different scales of RD farming to assess the impact of this system more thoroughly. © 2023 Society of Chemical Industry.

[Expression of BmSPI38 tandem multimers in Escherichia coli and its antifungal activity].

The aim of this study was to prepare tandem multimeric proteins of BmSPI38, a silkworm protease inhibitor, with better structural homogeneity, higher activity and stronger antifungal ability by protein engineering. The tandem multimeric proteins of BmSPI38 were prepared by prokaryotic expression technology. The effects of tandem multimerization on the structural homogeneity, inhibitory activity and antifungal ability of BmSPI38 were explored by in-gel activity staining of protease inhibitor, protease inhibition assays and fungal growth inhibition experiments. Activity staining showed that the tandem expression based on the peptide flexible linker greatly improved the structural homogeneity of BmSPI38 protein. Protease inhibition experiments showed that the tandem trimerization and tetramerization based on the linker improved the inhibitory ability of BmSPI38 to microbial proteases. Conidial germination assays showed that His6-SPI38L-tetramer had stronger inhibition on conidial germination of Beauveria bassiana than that of His6-SPI38-monomer. Fungal growth inhibition assay showed that the inhibitory ability of BmSPI38 against Saccharomyces cerevisiae and Candida albicans could be enhanced by tandem multimerization. The present study successfully achieved the heterologous active expression of the silkworm protease inhibitor BmSPI38 in Escherichia coli, and confirmed that the structural homogeneity and antifungal ability of BmSPI38 could be enhanced by tandem multimerization. This study provides important theoretical basis and new strategies for cultivating antifungal transgenic silkworm. Moreover, it may promote the exogenous production of BmSPI38 and its application in the medical field.

Natto: A medicinal and edible food with health function.

Natto is a soybean product fermented by natto bacteria. It is rich in a variety of amino acids, vitamins, proteins and active enzymes. It has a number of biological activities, such as thrombolysis, prevention of osteoporosis, antibacterial, anticancer, antioxidant and so on. It is widely used in medicine, health-care food, biocatalysis and other fields. Natto is rich in many pharmacological active substances and has significant medicinal research value. This paper summarizes the pharmacological activities and applications of natto in and outside China, so as to provide references for further research and development of natto.

Exosomal circBBS2 inhibits ferroptosis by targeting miR-494 to activate SLC7A11 signaling in ischemic stroke.

Umbilical cord-mesenchymal stem cells (UC-MSCs)-derived exosomes have been considered as an effective treatment for ischemic stroke. CircRNA BBS2 (circBBS2) was demonstrated to be down-regulated in patients with ischemic stroke. However, the role of UC-MSCs-derived exosomal circBBS2 in ischemic stroke and potential mechanisms remain unclear. Hypoxia/reperfusion (H/R)-exposed SH-SY5Y cells and middle cerebral artery occlusion (MCAO)-treated rats were served as in vitro and in vivo models of ischemic stroke. Target gene expression was detected by qRT-PCR. Cell viability was assessed by MTT assay. Ferroptosis was determined by iron, MDA, GSH, and lipid ROS levels. Protein levels were measured by Western blotting. The target relationships among circBBS2, miR-494, and SLC7A11 were validated by RNA-pull down, RIP, and dual-luciferase reporter assays. TTC and HE staining were performed to evaluate cerebral infarction volume and neuropathological changes. circBBS2 was lowly expressed and ferroptosis was triggered in MCAO rats and H/R-stimulated SH-SY5Y cells. UC-MSCs-derived exosomes enhanced cell viability and restrained ferroptosis via increasing circBBS2 expression in SH-SY5Y cells. Mechanistically, circBBS2 sponged miR-494 to enhance the SLC7A11 level. Knockdown of miR-494 or SLC7A11 reversed the effects of silencing circBBS2 or miR-494 on ferroptosis of SH-SY5Y cells, respectively. Furthermore, UC-MSCs-derived exosomes attenuated ischemic stroke in rats via delivering circBBS2 to inhibit ferroptosis. UC-MSCs-derived exosomal circBBS2 enhanced SLC7A11 expression via sponging miR-494, therefore repressing ferroptosis and relieving ischemic stroke. Our findings shed light on a novel mechanism for UC-MSCs-derived exosomes in the treatment of ischemic stroke.

A Microfluidic Device for Tobacco Ringspot Virus Detection by Electrochemical Impedance Spectroscopy.

Aiming at the problem of how to achieve the rapid detection of pathogenic microorganisms, this paper takes tobacco ringspot virus as the detection object, designs the impedance detection and analysis platform of tobacco ringspot virus based on microfluidic impedance method, establishes an equivalent circuit model to analyze the experimental results, and determines the optimal detection frequency of tobacco ringspot virus detection. Based on this frequency, an impedance-concentration regression model was established for the detection of tobacco ringspot virus in a tobacco ringspot virus detection device. Based on this model, a tobacco ringspot virus detection device was designed by using an AD5933 impedance detection chip. A comprehensive test study was carried out on the developed tobacco ringspot virus detection device through various testing methods, which verified the feasibility of the tobacco ringspot virus detection device and provided technical support for the field detection of pathogenic microorganisms.

Synergistic effects of extrinsic photoconduction and photogating in a short-wavelength ZrS3 infrared photodetector.

Two-dimensional (2D) material-based photodetectors, especially those working in the infrared band, have shown great application potential in the thermal imaging, optical communication, and medicine fields. Designing 2D material photodetectors with broadened detection band and enhanced responsivity has become an attractive but challenging research direction. To solve this issue, we report a zirconium trisulfide (ZrS3) infrared photodetector with enhanced and broadened response with the assistance of the synergistic effects of extrinsic photoconduction and photogating effect. The ZrS3 photodetectors can detect infrared light up to 2 µm by extrinsic photoconduction and exhibit a responsivity of 100 mA W-1 under 1550 nm illumination. Furthermore, the ZrS3 infrared photodetectors with an oxide layer show a triple enhanced responsivity due to the photogating effect. Additionally, the infrared imaging capability of the ZrS3 infrared photodetectors is also demonstrated. This work provides a potential way to extend the response range and improve the responsivity for nanomaterial-based photodetectors at the same time.

Screening for important risk factors for cancer-specific mortality in patients with localized clear cell renal carcinoma.

Aim: To study the risk factors for cancer-specific mortality (CSM) among patients with localized clear cell renal carcinoma (LCCRC) in the Chinese population. Methods: The clinical data of 1,376 LCCRC patients were postoperatively collected to analyze the correlations between CSM and multiple factors using Cox regression analysis. Receiver operating characteristic curves were constructed as per the screened risk factors to identify factors with optimal criticality judgment values, which were then used as the scoring standard for the stratification evaluation of LCCRC prognosis. Results: The CSM rate was 5.6% (77/1,376 cases) and the median follow-up duration was 78.1 (60-105) months. Cox analysis revealed that age, tumor diameter, and nuclear grade were associated with CSM. The optimal criticality judgment values for age and tumor diameter using receiver operating characteristic curve analysis were 53 years and 5.8 cm, respectively. LCCRC prognosis divided into low-risk (≤ 2 points), intermediate-risk (3-4 points), and high-risk (5 points) showed CSM rates of 3.8%, 13.8%, and 58.3%, respectively, among patients with more than 5 years of follow-up. Conclusions: Age, tumor diameter, and nuclear grade were important risk factors for CSM in LCCRC patients. The scoring criteria including these three risk factors may be an important supplement to the prognostic model of LCCRC in the Chinese population.

Amino Acid Substitutions at P1 Position Change the Inhibitory Activity and Specificity of Protease Inhibitors BmSPI38 and BmSPI39 from Bombyx mori.

It was found that silkworm serine protease inhibitors BmSPI38 and BmSPI39 were very different from typical TIL-type protease inhibitors in sequence, structure, and activity. BmSPI38 and BmSPI39 with unique structure and activity may be good models for studying the relationship between the structure and function of small-molecule TIL-type protease inhibitors. In this study, site-directed saturation mutagenesis at the P1 position was conducted to investigate the effect of P1 sites on the inhibitory activity and specificity of BmSPI38 and BmSPI39. In-gel activity staining and protease inhibition experiments confirmed that BmSPI38 and BmSPI39 could strongly inhibit elastase activity. Almost all mutant proteins of BmSPI38 and BmSPI39 retained the inhibitory activities against subtilisin and elastase, but the replacement of P1 residues greatly affected their intrinsic inhibitory activities. Overall, the substitution of Gly54 in BmSPI38 and Ala56 in BmSPI39 with Gln, Ser, or Thr was able to significantly enhance their inhibitory activities against subtilisin and elastase. However, replacing P1 residues in BmSPI38 and BmSPI39 with Ile, Trp, Pro, or Val could seriously weaken their inhibitory activity against subtilisin and elastase. The replacement of P1 residues with Arg or Lys not only reduced the intrinsic activities of BmSPI38 and BmSPI39, but also resulted in the acquisition of stronger trypsin inhibitory activities and weaker chymotrypsin inhibitory activities. The activity staining results showed that BmSPI38(G54K), BmSPI39(A56R), and BmSPI39(A56K) had extremely high acid-base and thermal stability. In conclusion, this study not only confirmed that BmSPI38 and BmSPI39 had strong elastase inhibitory activity, but also confirmed that P1 residue replacement could change their activity and inhibitory specificity. This not only provides a new perspective and idea for the exploitation and utilization of BmSPI38 and BmSPI39 in biomedicine and pest control, but also provides a basis or reference for the activity and specificity modification of TIL-type protease inhibitors.

Antireflux Ureteral Stent Improves Stent-Related Symptoms and Quality of Life: A Prospective Randomized Controlled Trial.

Objectives: To compare the effectiveness of antireflux ureteral stents on improving symptoms and quality of life of patients with ureteral stents. Materials and Methods: We randomized 120 patients with ureteral stone who required ureteral stent placement after ureteroscopic lithotripsy, of which 107 (56 in standard ureteral stent group and 51 in antireflux ureteral stent group) entered the final analysis. Severity of flank pain and suprapubic pain, visual analog scale (VAS), analgesic used after hospitalization, back soreness during micturition, gross hematuria, creatinine abnormality, hydronephrosis grade, symptomatic urinary tract infection (UTI), and quality of life were compared between the two groups. Results: There were no serious complications after operation in all 107 cases. The antireflux ureteral stent group had less flank pain and suprapubic pain (p < 0.05), analgesic used after hospitalization (p < 0.05), back soreness during micturition (p < 0.05), and lower VAS (p < 0.05). The health status index scores (p < 0.05), dimensions of usual activities, and pain/discomfort (p < 0.05) in the antireflux ureteral stent group were statistically better than those in the standard ureteral stent group. There were no significant differences between the groups in creatinine abnormality, hydronephrosis grade, gross hematuria, and symptomatic UTI. Conclusions: The antireflux ureteral stent has the same safety and efficacy as the standard ureteral stent, and is significantly better than the standard ureteral stent in flank pain and suprapubic pain, VAS, analgesic used after hospitalization, back soreness during micturition, and quality of life.

Tandem Multimerization Can Enhance the Structural Homogeneity and Antifungal Activity of the Silkworm Protease Inhibitor BmSPI39.

Previous studies have shown that BmSPI39, a serine protease inhibitor of silkworm, can inhibit virulence-related proteases and the conidial germination of insect pathogenic fungi, thereby enhancing the antifungal capacity of Bombyx mori. The recombinant BmSPI39 expressed in Escherichia coli has poor structural homogeneity and is prone to spontaneous multimerization, which greatly limits its development and application. To date, the effect of multimerization on the inhibitory activity and antifungal ability of BmSPI39 remains unknown. It is urgent to explore whether a BmSPI39 tandem multimer with better structural homogeneity, higher activity and a stronger antifungal ability can be obtained by protein engineering. In this study, the expression vectors of BmSPI39 homotype tandem multimers were constructed using the isocaudomer method, and the recombinant proteins of tandem multimers were obtained by prokaryotic expression. The effects of BmSPI39 multimerization on its inhibitory activity and antifungal ability were investigated by protease inhibition and fungal growth inhibition experiments. In-gel activity staining and protease inhibition assays showed that tandem multimerization could not only greatly improve the structural homogeneity of the BmSPI39 protein, but also significantly increase its inhibitory activity against subtilisin and proteinase K. The results of conidial germination assays showed that tandem multimerization could effectively enhance the inhibitory ability of BmSPI39 on the conidial germination of Beauveria bassiana. A fungal growth inhibition assay showed that BmSPI39 tandem multimers had certain inhibitory effects on both Saccharomyces cerevisiae and Candida albicans. The inhibitory ability of BmSPI39 against these the above two fungi could be enhanced by tandem multimerization. In conclusion, this study successfully achieved the soluble expression of tandem multimers of the silkworm protease inhibitor BmSPI39 in E. coli and confirmed that tandem multimerization can improve the structural homogeneity and antifungal ability of BmSPI39. This study will not only help to deepen our understanding of the action mechanism of BmSPI39, but also provide an important theoretical basis and new strategy for cultivating antifungal transgenic silkworms. It will also promote its exogenous production and development and application in the medical field.

Development of a Novel Real-Time Quantitative PCR Method for Detection of Ilyonectria robusta, the Predominant Species Causing Ginseng Rusty Root Rot.

Rusty root rot is the most destructive soilborne disease of ginseng caused by pathogenic Ilyonectria spp., predominantly Ilyonectria robusta, in China. However, there remains no effective strategy to control the disease. Current control of the disease requires that soil and ginseng seeds and seedlings infected with I. robusta are avoided during planting. Therefore, rapid and accurate detection of I. robusta would be indispensable in disease control programs. A one-step polymerase chain reaction (PCR) and quantitative real-time PCR (qPCR) assay was developed to detect I. robusta in ginseng seeds, roots, and soil. The species-specific primers HIS H3-F and HIS H3-R, designed based on a partial histone gene sequence of I. robusta, yielded a 268-bp product using the optimized PCR and qPCR protocol. DNA of I. robusta was detected by qPCR in all diseased soil and ginseng roots and seeds resulting from artificial inoculation and sampled from natural fields. I. robusta was detected at an abundance of 1.42 fg/µl at 12 h postinoculation and 191.31 fg/µl at 7 days postinoculation in ginseng roots that showed disease symptoms. In naturally infected soil sampled from ginseng fields, pathogen abundances ranging from 13.23 to 503.39 fg/µl were detected, which were 2.04 to 11.01 times higher than those in ginseng roots. The pathogen was first detected and was more abundant on the surface of the ginseng seed coat compared with that in the seed kernel. This study provides a high-efficiency detection technique for early diagnosis of I. robusta and real-time disease prevention and control strategies.

Straw incorporation interacting with earthworms mitigates N2O emissions from upland soil in a rice-wheat rotation system.

Intensive attentions have been paid to the positive effects on nitrous oxide (N2O) production under straw return or the presence of earthworms. Straw return as a sustainable practice can promote earthworm growth, how the interactions between straw and earthworms affect N2O production is still not well known. A split-plot field experiment (straw return as main plot and earthworm addition as subplot) was performed to quantify the interactive effects of straw and earthworm on N2O emissions from a wheat field and to determine the underlying mechanisms from nitrification and denitrification processes. The results showed that straw return significantly increased N2O emissions by 41.0 % under no earthworm addition but decreased it by 19.0 % under earthworm addition compared with straw removal (P < 0.05). The significant interaction between straw and earthworm benefits the mitigation of N2O emissions. Random forest model showed that denitrification and nitrification were dominant processes to affect N2O emissions at the jointing and booting growth stages of wheat, respectively. The interaction between straw and earthworm significantly decreased the abundances of N2O-producing bacterial genes such as nirS and nirK at the jointing stages, and AOB at the booting stages. The contrasting mechanisms in regulating N2O emissions at different growth stages should be considered in nitrogen recycling models to accurately predict available N and N2O dynamics. Our findings suggest that N2O emissions under straw return can be weakened with the increasing earthworm populations under the scenario of widely used conservation practices (e.g., straw return and no-till) due to significant interaction between straw and earthworms.