The superconducting magnet system of a fusion reactor plays a vital role in plasma confinement,a process that can be dis-rupted by various operational factors.A critical parameter for evaluating the temperature margin...The superconducting magnet system of a fusion reactor plays a vital role in plasma confinement,a process that can be dis-rupted by various operational factors.A critical parameter for evaluating the temperature margin of superconducting magnets during normal operation is the nuclear heating caused by D-T neutrons.This study investigates the impact of nuclear heat-ing on a superconducting magnet system by employing an improved analysis method that combines neutronics and thermal hydraulics.In the magnet system,toroidal field(TF)magnets are positioned closest to the plasma and bear the highest nuclear-heat load,making them prime candidates for evaluating the influence of nuclear heating on stability.To enhance the modeling accuracy and facilitate design modifications,a parametric TF model that incorporates heterogeneity is established to expedite the optimization design process and enhance the accuracy of the computations.A comparative analysis with a homogeneous TF model reveals that the heterogeneous model improves accuracy by over 12%.Considering factors such as heat load,magnetic-field strength,and cooling conditions,the cooling circuit facing the most severe conditions is selected to calculate the temperature of the superconductor.This selection streamlines the workload associated with thermal-hydraulic analysis.This approach enables a more efficient and precise evaluation of the temperature margin of TF magnets.Moreover,it offers insights that can guide the optimization of both the structure and cooling strategy of superconducting magnet systems.展开更多
BACKGROUND The occurrence of postoperative depression and anxiety in patients with endomet-riosis(EMS)not only causes psychological distress,but may also harm their physical health.AIM To explore the postoperative dep...BACKGROUND The occurrence of postoperative depression and anxiety in patients with endomet-riosis(EMS)not only causes psychological distress,but may also harm their physical health.AIM To explore the postoperative depression status,and its influencing factors,of EMS patients with reproductive intention.METHODS A total of 321 EMS patients with reproductive intent were included.Using the self-rating anxiety scale and self-rating depression scale,EMS patients with anxiety or depression were distinguished.A clinical model for predicting anxiety or depression in EMS patients was constructed and evaluated using a nomogram,receiver operating characteristic curve,and calibration curve.RESULTS The results of the single factor analysis showed that smoking,coffee,EMS stage,chronic pelvic pain,and sexual discomfort may be related to anxiety.Further,smoking,drinking,spouse,annual household income and EMS stage may be related to depression in EMS patients.Multivariate logistic regression illustrated that smoking,coffee,chronic pelvic pain and sexual discomfort may be inde-pendent risk factors for anxiety in EMS patients,while smoking,EMS stage(Phase III and Phase IV),spouse and high annual household income may be independent risk factors for depression in EMS patients.Additionally,the models used to predict the risk of anxiety or depression in EMS patients have good predictive value.CONCLUSION The anxiety and depression of EMS patients may be related to many factors.In clinical treatment,additional attention should be paid to the psychological status of EMS patients.展开更多
Gandou decoction(GDD),a well-known traditional Chinese medicine(TCM)formula,has been widely used for decades to treat Wilson's disease(WD)in China due to its remarkable clinical effects.However,the chemical consti...Gandou decoction(GDD),a well-known traditional Chinese medicine(TCM)formula,has been widely used for decades to treat Wilson's disease(WD)in China due to its remarkable clinical effects.However,the chemical constituents of GDD still remain unclear because of their complexity.In this work,a reliable and sensitive strategy based on ultra-performance liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry(UPLC-Q-TOF-MSE)and UNIFI informatics platform was applied to investigate the chemical components in GDD.In total,96 compounds including anthraquinones,alkaloids,protostane triterpenoids,flavonoids,triterpenoid saponins,tannins,curcuminoids,etc,were identified or tentatively characterized from GDD by comparing their retention time,accurate mass within 5 ppm error and MSE fragmentation patterns.Among them,eleven compounds were confirmed unambiguously with reference standards.Representative compounds in different chemical structure types were analyzed in fragmentation patterns and characteristic ions.Moreover,to better understand the chemical contribution of individual herbs to the whole decoction,the corresponding each herb in GDD was also detected.This study developed a rapid method for characterizing the chemical constituents in GDD,which could not only be used for chemical standardization and quality control,but also be helpful for further research of GDD in vivo.展开更多
Nanosized tungsten carbide(WC)/carbon(C)catalyst was synthesized via a novel ultra-rapid confinement combustion synthesis method.The amount of activated carbon(AC)plays an important role in the morphology and structur...Nanosized tungsten carbide(WC)/carbon(C)catalyst was synthesized via a novel ultra-rapid confinement combustion synthesis method.The amount of activated carbon(AC)plays an important role in the morphology and structure,controlling both the precursor and final powder.The WC particles synthesized inside the pores of the AC had been 10-20 nm because of the confinement of the pore structure and the large specific surface area of AC.When used for oxygen reduction performance,the half-wave potential was−0.24 V,and the electron transfer number was 3.45,indicating the main reaction process was the transfer of four electrons.The detailed electrocatalytic performance and underlying mechanism were investigated in this work.Our study provides a novel approach for the design of catalysts with new compositions and new structures,which are significant for promoting the commercialization of fuel cells.展开更多
AIM: To determine the association between retinal vasculature changes and stroke.METHODS: MEDLINE and EMBASE were searched for relevant human studies to September 2015 that investigated the association between retin...AIM: To determine the association between retinal vasculature changes and stroke.METHODS: MEDLINE and EMBASE were searched for relevant human studies to September 2015 that investigated the association between retinal vasculature changes and the prevalence or incidence of stroke; the studies were independently examined for their qualities. Data on clinical characteristics and calculated summary odds ratios (ORs) were extracted for associations between retinal microvascular abnormalities and stroke, including stroke subtypes where possible, and adjusted for key variables. RESULTS: Nine cases were included in the study comprising 20 659 patients, 1178 of whom were stroke patients. The retinal microvascular morphological markers used were hemorrhage, microaneurysm, vessel caliber, arteriovenous nicking, and fractal dimension. OR of retinal arteriole narrowing and retinal arteriovenous nicking and stroke was 1.42 and 1.91, respectively, indicating that a small-caliber retinal arteriole and retinal arteriovenous nicking were associated with stroke. OR of retinal hemorrhage and retinal microaneurysm and stroke was 3.21 and 3.83, respectively, indicating that retinal microvascular lesions were highly associated with stroke. Results also showed that retinal fractal dimension reduction was associated with stroke (OR: 2.28 for arteriole network, OR: 1.80 for venular network).CONCLUSION: Retinal vasculature changes have a specific relationship to stroke, which is promising evidence for the prediction of stroke using computerized retinal vessel analysis.展开更多
The prolonged mei-yu/baiu system with anomalous precipitation in the year 2020 has swollen many rivers and lakes,caused flash flooding,urban flooding and landslides,and consistently wreaked havoc across large swathes ...The prolonged mei-yu/baiu system with anomalous precipitation in the year 2020 has swollen many rivers and lakes,caused flash flooding,urban flooding and landslides,and consistently wreaked havoc across large swathes of China,particularly in the Yangtze River basin.Significant precipitation and flooding anomalies have already been seen in magnitude and extension so far this year,which have been exerting much higher pressure on emergency responses in flood control and mitigation than in other years,even though a rainy season with multiple ongoing serious flood events in different provinces is not that uncommon in China.Instead of delving into the causes of the uniqueness of this year’s extreme precipitation-flooding situation,which certainly warrants in-depth exploration,in this article we provide a short view toward a more general hydrometeorological solution to this annual nationwide problem.A“glocal”(global to local)hydrometeorological solution for floods(GHS-F)is considered to be critical for better preparedness,mitigation,and management of different types of significant precipitation-caused flooding,which happen extensively almost every year in many countries such as China,India and the United States.Such a GHS-F model is necessary from both scientific and operational perspectives,with the strength in providing spatially consistent flood definitions and spatially distributed flood risk classification considering the heterogeneity in vulnerability and resilience across the entire domain.Priorities in the development of such a GHS-F are suggested,emphasizing the user’s requirements and needs according to practical experiences with various flood response agencies.展开更多
Qi-Yu-San-Long decoction(QYSLD)is a traditional Chinese medicine that has been clinically used in the treatment of non-small-cell lung cancer(NSCLC)for more than 20 years.However,to date,metabolicrelated studies on QY...Qi-Yu-San-Long decoction(QYSLD)is a traditional Chinese medicine that has been clinically used in the treatment of non-small-cell lung cancer(NSCLC)for more than 20 years.However,to date,metabolicrelated studies on QYSLD have not been performed.In this study,a post-targeted screening strategy based on ultra-performance liquid chromatography coupled with quadrupole time-of-flight full information tandem mass spectrometry(UPLC-QTOF-MS^(E))was developed to identify QYSLD-related xenobiotics in rat urine.The chemical compound database of QYSLD constituents was established from previous research,and metabolites related to these compounds were predicted in combination with their possible metabolic pathways.The metabolites were identified by extracted ion chromatograms using predicted m/z values as well as retention time,excimer ions,and fragmentation behavior.Overall,85 QYSLD-related xenobiotics(20 prototype compounds and 65 metabolites)were characterized from rat urine.The main metabolic reactions and elimination features of QYSLD included oxidation,reduction,decarboxylation,hydrolysis,demethylation,glucuronidation,sulfation,methylation,deglycosylation,acetylation,and associated combination reactions.Of the identified molecules,14 prototype compounds and 58 metabolites were slowly eliminated,thus accumulating in vivo over an extended period,while five prototypes and two metabolites were present in vivo for a short duration.Furthermore,one prototype and five metabolites underwent the process of“appearing-disappearing-reappearing”in vivo.Overall,the metabolic profile and characteristics of QYSLD in rat urine were determined,which is useful in elucidating the active components of the decoction in vivo,thus providing the basis for studying its mechanism of action.展开更多
BACKGROUND Dubin-Johnson syndrome(DJS)is a benign autosomal recessive liver disease involving mutations of the ABCC2 gene.It is characterized by chronic or intermittent conjugated hyperbilirubinemia,with chronic idiop...BACKGROUND Dubin-Johnson syndrome(DJS)is a benign autosomal recessive liver disease involving mutations of the ABCC2 gene.It is characterized by chronic or intermittent conjugated hyperbilirubinemia,with chronic idiopathic jaundice as the main clinical manifestation.Genetic alterations of the ABCC2 gene are commonly used for diagnosing DJS;however,the causative ABCC2 point mutation in Chinese patients remains unknown.Research on ABCC2 mutations in Chinese DJS patients is extremely rare,and the diagnosis of DJS remains limited.The routine analysis of ABCC2 mutations is helpful for the diagnosis of DJS.Here,we report the clinical characteristics and ABCC2 genotype of an adult female DJS patient.This article is to expound the discovery of more potentially pathogenic ABCC2 variants will that contribute to DJS identification.CASE SUMMARY This study investigated a woman referred for DJS and involved clinical and genetic analyses.ABCC2 mutations were identified by next-generation sequencing(NGS).The patient showed intermittent jaundice and conjugated hyperbilirubinemia.Histopathological examinations were consistent with the typical phenotype of DJS.Genetic diagnostic analysis revealed an ABCC2 genotype exhibiting a pathogenic variant,namely c.2443C>T(p.Arg815*),which has not been reported previously in the domestic or foreign literature.CONCLUSION Pathogenic ABCC2 mutations play an important role in the diagnosis of DJS,especially in patients with atypical presentations.Currently,NGS is used in the routine analysis of DJS cases and such tests of further cases will better illuminate the relationship between various genotypes and phenotypes of DJS.展开更多
Previous studies have shown that leak electro ns in cusped field thrusters can move along the channel axis to the anode after crossing the magnetic cusp on the exit.In this paper,a onedimensional fluid model is built ...Previous studies have shown that leak electro ns in cusped field thrusters can move along the channel axis to the anode after crossing the magnetic cusp on the exit.In this paper,a onedimensional fluid model is built along two typical electron paths to study the influence of leak electrons on the discharge characteristics of a cusped field thruster,considering the electron temperature equation.It is found that the frequencies of low-frequency oscillations increase with a decrease in the proportion of leak electrons,which is related to an increase in the ion speed in the channel.Simulation results show that the position of the peak electron temperature is near the magnetic cusp on the exit and the position of the peak electron density is located downstream from the middle magnetic tip.With a decrease in the proportion of the leak electrons,the peak electron temperature and peak electron density decrease and the position of the peak electron density moves away from the exit,which is related to a decrease in the potential fall on the exit and an increase in confinement of electrons to the middle magnetic cusp.展开更多
Background: A series of modified montmorillonites(Mt) including zinc-loaded Mt(Zn-Mt), copper-loaded Mt(Cu-Mt), copper/zinc-loaded Mt with different Cu/Zn ratio(Cu/Zn-Mt-1, Cu/Zn-Mt-2, Cu/Zn-Mt-3) were prepar...Background: A series of modified montmorillonites(Mt) including zinc-loaded Mt(Zn-Mt), copper-loaded Mt(Cu-Mt), copper/zinc-loaded Mt with different Cu/Zn ratio(Cu/Zn-Mt-1, Cu/Zn-Mt-2, Cu/Zn-Mt-3) were prepared by an ion-exchange reaction, and characterized using X-ray diffraction(XRD), fourier transformed infrared spectroscopy(FTIR) and transmission electron microscopy(TEM). The specific surface areas, antimicrobial activity and cytotoxicity of the modified Mt were investigated.Results: In the modified Mt, hydrated Cu ions and Zn ions were exchanged in the interlayer space of Mt and the particles were irregular shapes. The results showed that Cu/Zn-Mt enhanced antibacterial and antifungal activity compared with Zn-Mt and Cu-Mt possibly due to the synergistic effect between Cu and Zn. Among the Cu/Zn-Mt with different Cu/Zn raitos, Cu/Zn-Mt with a Cu/Zn ratio of 0.98 or 0.51 showed higher antimicrobial activity against gram-negative bacteria(Escherichia coli), gram-positive bacteria(Staphylococcus aureus), fungi(Candida albicans).Moreover, the antimicrobial activity of Cu/Zn-Mt was correlated with its specific surface area. Cytotoxicity studies on IPEC-J2 cell showed a slight cytotoxicity of Cu/Zn-Mt.Conclusions: The current data provide clear evidence that in terms of its antimicrobial activity and relatively low toxicity, the Cu/Zn-Mt holds great promise for applications in animal husbandry.展开更多
AIM: To ensure the diagnostic value of computer aided techniques in diabetic retinopathy(DR) detection based on ophthalmic photography(OP). METHODS: PubM ed, EMBASE, Ei village, IEEE Xplore and Cochrane Library databa...AIM: To ensure the diagnostic value of computer aided techniques in diabetic retinopathy(DR) detection based on ophthalmic photography(OP). METHODS: PubM ed, EMBASE, Ei village, IEEE Xplore and Cochrane Library database were searched systematically for literatures about computer aided detection(CAD) in DR detection. The methodological quality of included studies was appraised by the Quality Assessment Tool for Diagnostic Accuracy Studies(QUADAS-2). Meta-Di Sc was utilized and a random effects model was plotted to summarize data from those included studies. Summary receiver operating characteristic curves were selected to estimate the overall test performance. Subgroup analysis was used to identify the efficiency of CAD in detecting DR, exudates(EXs), microaneurysms(MAs) as well as hemorrhages(HMs), and neovascularizations(NVs). Publication bias was analyzed using STATA. RESULTS: Fourteen articles were finally included in this Meta-analysis after literature review. Pooled sensitivity and specificity were 90%(95%CI, 85%-94%) and 90%(95%CI, 80%-96%) respectively for CAD in DR detection. With regard to CAD in EXs detecting, pooled sensitivity, specificity were 89%(95%CI, 88%-90%) and99%(95%CI, 99%-99%) respectively. In aspect of MAs and HMs detection, pooled sensitivity and specificity of CAD were 42%(95%CI, 41%-44%) and 93%(95%CI, 93%-93%) respectively. Besides, pooled sensitivity and specificity were 94%(95%CI, 89%-97%) and 87%(95%CI, 83%-90%) respectively for CAD in NVs detection. No potential publication bias was observed. CONCLUSION: CAD demonstrates overall high diagnostic accuracy for detecting DR and pathological lesions based on OP. Further prospective clinical trials are needed to prove such effect.展开更多
Objective: The aim is to understand the status of rural medical waste management and problems and to make recommendations. Methods: The questionnaire survey, interviews and comparative analysis are used. Results: Comp...Objective: The aim is to understand the status of rural medical waste management and problems and to make recommendations. Methods: The questionnaire survey, interviews and comparative analysis are used. Results: Compared with urban medical waste management, rural medical waste management is weaker in classification, unified recycle, disposals, protect measures of related personnel, regulations and policies of awareness. Conclusion: It is recommended to improve policies and regulations of rural medical waste management, strengthen rural infrastructures and facilities, improve supervision and innovates means of supervision.展开更多
The reasons for bringing surface accuracy error in ultra-precision grinding ceramic ball joint were analyzed,and the influences wheel position error and shaft run-out error on the ball joint surface accuracy were disc...The reasons for bringing surface accuracy error in ultra-precision grinding ceramic ball joint were analyzed,and the influences wheel position error and shaft run-out error on the ball joint surface accuracy were discussed.Through establishing three-dimensional grinding model,the mathematical relationship between the position error and surface accuracy was derived,and the distance from any point on spherical surface to the ideal center was calculated when position error existed,and a precise surface shape was got,and theoretical support was provided to improve the surface accuracy during the grinding process.Using self-developed ultraprecision grinding machine to do the ceramic ball grinding experiment,the surface accuracy PV value of ceramic spherical joint is 4.8μm.展开更多
Due to medical waste’s infection and hazard, it can cause potential environmental and public health risks, so medical waste management is of great importance especially in developing countries. The objective of the s...Due to medical waste’s infection and hazard, it can cause potential environmental and public health risks, so medical waste management is of great importance especially in developing countries. The objective of the study was to analyze and assess current status of medical waste management in the light of semi-structured interview in medical institutions and the medical waste disposal centre. As a medium-sized city of China and its respective nature, Xinxiang was selected as the case study. In order to significantly improve eco-efficiency of medical waste management (MWM) and minimize the environmental risks, this paper identified key factors determining the implementation of MWM on the basis of the local realities and situations of medical waste, and then an integrated MWM system was developed. Such the regulations should be improved;MWM database platform should be strengthened;unified coordination ability of the MWM should be developed;and a suitable rural recycling network should be set up.展开更多
DEAR EDITOR Centenarians are a typical longevity model characterized by delayed onset of morbidity in age-related diseases such as cancer, cardiovascular disease, dementia, and stroke (Andersen et al, 2012). Though ...DEAR EDITOR Centenarians are a typical longevity model characterized by delayed onset of morbidity in age-related diseases such as cancer, cardiovascular disease, dementia, and stroke (Andersen et al, 2012). Though there may be a number of underlying mechanisms behind this longevity, curiously it seems that the survival advantage persists in their offspring (Terry et al, 2003), suggesting a potentially important role for genetic factors. Previous studies suggested that the heritability of human longevity may be ~25% (Herskind et al, 1996; Mcgue et al, 1993), whicih is consistent with other studies on model organisms that identified several longevity-related genes, such as age-l, daf-2, daf-16, and sir-2 (Friedman & Johnson, 1988; Kenyon et al, 1993; Lin et al, 1997; Tissenbaum & Guarente, 2001). Likewise, several studies have reported the existence of many mutations related to human longevity (Holstege et al, 2014; Sebastiani et al, 2012).展开更多
The complexities of energy transfer mechanisms in the flagella of mammalian sperm flagella have been intensively investigated and demonstrate significant diversity across species.Enzymatic shuttles,particularly adenyl...The complexities of energy transfer mechanisms in the flagella of mammalian sperm flagella have been intensively investigated and demonstrate significant diversity across species.Enzymatic shuttles,particularly adenylate kinase(AK)and creatine kinase(CK),are pivotal in the efficient transfer of intracellular ATP,showing distinct tissue-and species-specificity.Here,the expression profiles of AK and CK were investigated in mice and found to fall into four subgroups,of which Subgroup III AKs were observed to be unique to the male reproductive system and conserved across chordates.Both AK8 and AK9 were found to be indispensable to male reproduction after analysis of an infertile male cohort.Knockout mouse models showed that AK8 and AK9 were central to promoting sperm motility.Immunoprecipitation combined with mass spectrometry revealed that AK8 and AK9 interact with the radial spoke(RS)of the axoneme.Examination of various human and mouse sperm samples with substructural damage,including the presence of multiple RS subunits,showed that the head of radial spoke 3 acts as an adapter for AK9 in the flagellar axoneme.Using an ATP probe together with metabolomic analysis,it was found that AK8 and AK9 cooperatively regulated ATP transfer in the axoneme,and were concentrated at sites associated with energy consumption in the flagellum.These findings indicate a novel function for RS beyond its structural role,namely,the regulation of ATP transfer.In conclusion,the results expand the functional spectrum of AK proteins and suggest a fresh model regarding ATP transfer within mammalian flagella.展开更多
Oligoasthenoteratozoospermia is an important factor affecting male fertility and has been found to be associated with genetic factors.However,there are stll a proportion of oligoasthenoteratozoospermia cases that cann...Oligoasthenoteratozoospermia is an important factor affecting male fertility and has been found to be associated with genetic factors.However,there are stll a proportion of oligoasthenoteratozoospermia cases that cannot be explained by known pathogenic genetic variants.Here,we perform genetic analyses and identify bi-allelic loss-of-function variants of MFSD6L from an oligoasthenoteratozoospermia-affected family.Mfsd6l knock-out male mice also present male subfertility with reduced sperm concentration,motility,and deformed acrosomes.Further mechanistic analyses reveal that MFsD6L,as an acrosome membrane protein,plays an important role in the formation of acrosome by interacting with the inner acrosomal membrane protein SPACA1.Moreover,poor embryonic development is consistently observed after intracytoplasmic sperm injection treatment using spermatozoa from the MFSD6L-deficient man and male mice.Collectively,our findings reveal that MFSD6L is required for the anchoring of sperm acrosome and head shaping.The deficiency of MFsD6L affects male fertility and causes oligoasthenoter-atozoospermia in humans and mice.展开更多
Anti-predation strategies are critical to animal survival and are fundamental to deciphering predator–prey interactions.As an important defense strategy,sensory predator detection(such as through acoustic and visual ...Anti-predation strategies are critical to animal survival and are fundamental to deciphering predator–prey interactions.As an important defense strategy,sensory predator detection(such as through acoustic and visual cues)enables animals to assess predation risk and execute predator-avoidance behavior;however,there are limited studies on the anti-predation behavior of nocturnal animals.The prey of bats provides an excellent representative system for examining the anti-predation behavior of nocturnal animals.Here,we broadcasted different types of echolocation calls of the bird-eating bat Ia io to two wild passerine birds,namely,Zosterops japonicus and Sinosuthora webbiana,that are preyed upon by I.io,and presented the birds with individual bats under different light intensities.The results showed that both bird species were able to perceive the low-frequency audible portion of the bats’echolocation calls;however,they did not exhibit escape responses to the acoustic stimuli.In the dark and under moonlit conditions,both bird species were unable to respond to active bats at close range and the birds only exhibited evasive flight behavior when bats approached or touched them.These results suggest that nocturnal passerine birds may not be able to use acoustic or visual cues to detect bats and adopt evasive maneuvers to avoid predation.This work suggests that bat predation pressure may not elicit primary predator-avoidance responses in nocturnal passerine birds.The results provide new insights into the anti-predation behavior of nocturnal animals.展开更多
Gerbera(Gerbera hybrida),a major fresh cut flower crop,is very susceptible to root rot disease.Although plant defensins(PDFs),a major group of plant antimicrobial peptides,display broad-spectrum antifungal and antibac...Gerbera(Gerbera hybrida),a major fresh cut flower crop,is very susceptible to root rot disease.Although plant defensins(PDFs),a major group of plant antimicrobial peptides,display broad-spectrum antifungal and antibacterial activities,PDF genes in gerbera have not been systematically characterized.Here,we identified and cloned nine PDF genes from gerbera and divided them into two classes based on phylogenetic analysis.Most Class Ⅰ GhPDF genes were highly expressed in petioles,whereas all Class Ⅱ GhPDF genes were highly expressed in roots.Phytophthora cryptogea inoculation strongly upregulated all Class II GhPDF genes in roots and upregulated all Class Ⅰ GhPDF genes in petioles.Transient overexpression of GhPDF1.5 and GhPDF2.4 inhibited P.cryptogea infection in tobacco(Nicotiana benthamiana)leaves.Transient overexpression of GhPDF2.4,but not GhPDF1.5,significantly upregulated ACO and LOX gene expression in tobacco leaves,indicating that overexpressing GhPDF2.4 activated the jasmonic acid/ethylene defense pathway and that the two types of GhPDFs have different modes of action.Prokaryotically expressed recombinant GhPDF2.4 inhibited mycelial growth and delayed the hyphal swelling of P.cryptogea,in vitro,indicating that GhPDF2.4 is a morphogenetic defensin.Moreover,the addition of GhPDF2.4 to plant culture medium alleviated the root rot symptoms of in vitro-grown gerbera seedlings and greatly reduced pathogen titer in P.cryptogea-inoculated gerbera roots in the early stages of treatment.Our study provides a basis for the use of GhPDFs,especially GhPDF2.4,for controlling root rot disease in gerbera.展开更多
基金the National Natural Science Foundation of China(Nos.52222701,52077211,and 52307034).
文摘The superconducting magnet system of a fusion reactor plays a vital role in plasma confinement,a process that can be dis-rupted by various operational factors.A critical parameter for evaluating the temperature margin of superconducting magnets during normal operation is the nuclear heating caused by D-T neutrons.This study investigates the impact of nuclear heat-ing on a superconducting magnet system by employing an improved analysis method that combines neutronics and thermal hydraulics.In the magnet system,toroidal field(TF)magnets are positioned closest to the plasma and bear the highest nuclear-heat load,making them prime candidates for evaluating the influence of nuclear heating on stability.To enhance the modeling accuracy and facilitate design modifications,a parametric TF model that incorporates heterogeneity is established to expedite the optimization design process and enhance the accuracy of the computations.A comparative analysis with a homogeneous TF model reveals that the heterogeneous model improves accuracy by over 12%.Considering factors such as heat load,magnetic-field strength,and cooling conditions,the cooling circuit facing the most severe conditions is selected to calculate the temperature of the superconductor.This selection streamlines the workload associated with thermal-hydraulic analysis.This approach enables a more efficient and precise evaluation of the temperature margin of TF magnets.Moreover,it offers insights that can guide the optimization of both the structure and cooling strategy of superconducting magnet systems.
基金Research Funds of Center for Big Data and Population Health of IHM,No.JKS2022009Huaibei Science and Technology Plan Project,No.2021HK016.
文摘BACKGROUND The occurrence of postoperative depression and anxiety in patients with endomet-riosis(EMS)not only causes psychological distress,but may also harm their physical health.AIM To explore the postoperative depression status,and its influencing factors,of EMS patients with reproductive intention.METHODS A total of 321 EMS patients with reproductive intent were included.Using the self-rating anxiety scale and self-rating depression scale,EMS patients with anxiety or depression were distinguished.A clinical model for predicting anxiety or depression in EMS patients was constructed and evaluated using a nomogram,receiver operating characteristic curve,and calibration curve.RESULTS The results of the single factor analysis showed that smoking,coffee,EMS stage,chronic pelvic pain,and sexual discomfort may be related to anxiety.Further,smoking,drinking,spouse,annual household income and EMS stage may be related to depression in EMS patients.Multivariate logistic regression illustrated that smoking,coffee,chronic pelvic pain and sexual discomfort may be inde-pendent risk factors for anxiety in EMS patients,while smoking,EMS stage(Phase III and Phase IV),spouse and high annual household income may be independent risk factors for depression in EMS patients.Additionally,the models used to predict the risk of anxiety or depression in EMS patients have good predictive value.CONCLUSION The anxiety and depression of EMS patients may be related to many factors.In clinical treatment,additional attention should be paid to the psychological status of EMS patients.
基金This research was supported by the National Natural Science Foundation of China(No:81872976,81873038,81303245)Key Project of the National Science Fund of Anhui Province(No:KJ2016A398)+1 种基金Key Project Foundation of Oversea Visiting and Research for the Excellent Young and Middle-aged Faculties in Universities of Anhui Province(No:gxgwfx2018042)Primary Research&Development Plan of Anhui Province(No:201904a07020051).
文摘Gandou decoction(GDD),a well-known traditional Chinese medicine(TCM)formula,has been widely used for decades to treat Wilson's disease(WD)in China due to its remarkable clinical effects.However,the chemical constituents of GDD still remain unclear because of their complexity.In this work,a reliable and sensitive strategy based on ultra-performance liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry(UPLC-Q-TOF-MSE)and UNIFI informatics platform was applied to investigate the chemical components in GDD.In total,96 compounds including anthraquinones,alkaloids,protostane triterpenoids,flavonoids,triterpenoid saponins,tannins,curcuminoids,etc,were identified or tentatively characterized from GDD by comparing their retention time,accurate mass within 5 ppm error and MSE fragmentation patterns.Among them,eleven compounds were confirmed unambiguously with reference standards.Representative compounds in different chemical structure types were analyzed in fragmentation patterns and characteristic ions.Moreover,to better understand the chemical contribution of individual herbs to the whole decoction,the corresponding each herb in GDD was also detected.This study developed a rapid method for characterizing the chemical constituents in GDD,which could not only be used for chemical standardization and quality control,but also be helpful for further research of GDD in vivo.
基金This work was financially supported by the China Postdoctoral Science Foundation(No.2019M652169)the University Synergy Innovation Program of Anhui Province(No.GXXT-2019-016)+1 种基金the Natural Science Foundation of Anhui(No.JZ2018AKZR0063)the Fundamental Research Funds for the Central University,China(No.PA2019GDPK0044).
文摘Nanosized tungsten carbide(WC)/carbon(C)catalyst was synthesized via a novel ultra-rapid confinement combustion synthesis method.The amount of activated carbon(AC)plays an important role in the morphology and structure,controlling both the precursor and final powder.The WC particles synthesized inside the pores of the AC had been 10-20 nm because of the confinement of the pore structure and the large specific surface area of AC.When used for oxygen reduction performance,the half-wave potential was−0.24 V,and the electron transfer number was 3.45,indicating the main reaction process was the transfer of four electrons.The detailed electrocatalytic performance and underlying mechanism were investigated in this work.Our study provides a novel approach for the design of catalysts with new compositions and new structures,which are significant for promoting the commercialization of fuel cells.
基金Supported by the National Natural Science Foundation of China(No.81501559No.81271668)+4 种基金Natural Science Foundation of the Higher Education Institutions of Jiangsu Province(No.15KJB310015)Pre-research project for Natural Science Foundation of Nantong University(No.14ZY021)Science and Technology Project of Nantong City(No.MS12015105)Graduate Research and Innovation Plan Project of Nantong University(No.YKC14048No.YKC15056)
文摘AIM: To determine the association between retinal vasculature changes and stroke.METHODS: MEDLINE and EMBASE were searched for relevant human studies to September 2015 that investigated the association between retinal vasculature changes and the prevalence or incidence of stroke; the studies were independently examined for their qualities. Data on clinical characteristics and calculated summary odds ratios (ORs) were extracted for associations between retinal microvascular abnormalities and stroke, including stroke subtypes where possible, and adjusted for key variables. RESULTS: Nine cases were included in the study comprising 20 659 patients, 1178 of whom were stroke patients. The retinal microvascular morphological markers used were hemorrhage, microaneurysm, vessel caliber, arteriovenous nicking, and fractal dimension. OR of retinal arteriole narrowing and retinal arteriovenous nicking and stroke was 1.42 and 1.91, respectively, indicating that a small-caliber retinal arteriole and retinal arteriovenous nicking were associated with stroke. OR of retinal hemorrhage and retinal microaneurysm and stroke was 3.21 and 3.83, respectively, indicating that retinal microvascular lesions were highly associated with stroke. Results also showed that retinal fractal dimension reduction was associated with stroke (OR: 2.28 for arteriole network, OR: 1.80 for venular network).CONCLUSION: Retinal vasculature changes have a specific relationship to stroke, which is promising evidence for the prediction of stroke using computerized retinal vessel analysis.
基金This study was supported by the National Key R&D Program of China(Grant No.2017YFA0604300)the National Natural Science Foundation of China(Grant Nos.41861144014,41775106 and U1811464)+1 种基金the Program for Guangdong Introducing Innovative and Entrepreneurial Teams(Grant No.2017ZT07X355)the project of the Chinese Ministry of Emergency Management on“Catastrophe Evaluation Modeling Study”.
文摘The prolonged mei-yu/baiu system with anomalous precipitation in the year 2020 has swollen many rivers and lakes,caused flash flooding,urban flooding and landslides,and consistently wreaked havoc across large swathes of China,particularly in the Yangtze River basin.Significant precipitation and flooding anomalies have already been seen in magnitude and extension so far this year,which have been exerting much higher pressure on emergency responses in flood control and mitigation than in other years,even though a rainy season with multiple ongoing serious flood events in different provinces is not that uncommon in China.Instead of delving into the causes of the uniqueness of this year’s extreme precipitation-flooding situation,which certainly warrants in-depth exploration,in this article we provide a short view toward a more general hydrometeorological solution to this annual nationwide problem.A“glocal”(global to local)hydrometeorological solution for floods(GHS-F)is considered to be critical for better preparedness,mitigation,and management of different types of significant precipitation-caused flooding,which happen extensively almost every year in many countries such as China,India and the United States.Such a GHS-F model is necessary from both scientific and operational perspectives,with the strength in providing spatially consistent flood definitions and spatially distributed flood risk classification considering the heterogeneity in vulnerability and resilience across the entire domain.Priorities in the development of such a GHS-F are suggested,emphasizing the user’s requirements and needs according to practical experiences with various flood response agencies.
基金supported by grants from the National Natural Science Foundation of China(Grant No.:81903765)the Open Fund Project of Key Laboratory of Traditional Chinese Medicine for Prevention and Treatment of Major Pulmonary Diseases of the Anhui Provincial Department of Education(Grant No.:JYTKF2020-5)the Graduate Science and Technology Innovation Fund project of Anhui University of Chinese Medicine(Grant No.:2020YB06).
文摘Qi-Yu-San-Long decoction(QYSLD)is a traditional Chinese medicine that has been clinically used in the treatment of non-small-cell lung cancer(NSCLC)for more than 20 years.However,to date,metabolicrelated studies on QYSLD have not been performed.In this study,a post-targeted screening strategy based on ultra-performance liquid chromatography coupled with quadrupole time-of-flight full information tandem mass spectrometry(UPLC-QTOF-MS^(E))was developed to identify QYSLD-related xenobiotics in rat urine.The chemical compound database of QYSLD constituents was established from previous research,and metabolites related to these compounds were predicted in combination with their possible metabolic pathways.The metabolites were identified by extracted ion chromatograms using predicted m/z values as well as retention time,excimer ions,and fragmentation behavior.Overall,85 QYSLD-related xenobiotics(20 prototype compounds and 65 metabolites)were characterized from rat urine.The main metabolic reactions and elimination features of QYSLD included oxidation,reduction,decarboxylation,hydrolysis,demethylation,glucuronidation,sulfation,methylation,deglycosylation,acetylation,and associated combination reactions.Of the identified molecules,14 prototype compounds and 58 metabolites were slowly eliminated,thus accumulating in vivo over an extended period,while five prototypes and two metabolites were present in vivo for a short duration.Furthermore,one prototype and five metabolites underwent the process of“appearing-disappearing-reappearing”in vivo.Overall,the metabolic profile and characteristics of QYSLD in rat urine were determined,which is useful in elucidating the active components of the decoction in vivo,thus providing the basis for studying its mechanism of action.
基金Supported by The Talents of Qiankehe platform of China,No.[2018]5779-40the Zhuke Contract,No.[2018]1-92and the Qiankehe Support,No.[2017]2874.
文摘BACKGROUND Dubin-Johnson syndrome(DJS)is a benign autosomal recessive liver disease involving mutations of the ABCC2 gene.It is characterized by chronic or intermittent conjugated hyperbilirubinemia,with chronic idiopathic jaundice as the main clinical manifestation.Genetic alterations of the ABCC2 gene are commonly used for diagnosing DJS;however,the causative ABCC2 point mutation in Chinese patients remains unknown.Research on ABCC2 mutations in Chinese DJS patients is extremely rare,and the diagnosis of DJS remains limited.The routine analysis of ABCC2 mutations is helpful for the diagnosis of DJS.Here,we report the clinical characteristics and ABCC2 genotype of an adult female DJS patient.This article is to expound the discovery of more potentially pathogenic ABCC2 variants will that contribute to DJS identification.CASE SUMMARY This study investigated a woman referred for DJS and involved clinical and genetic analyses.ABCC2 mutations were identified by next-generation sequencing(NGS).The patient showed intermittent jaundice and conjugated hyperbilirubinemia.Histopathological examinations were consistent with the typical phenotype of DJS.Genetic diagnostic analysis revealed an ABCC2 genotype exhibiting a pathogenic variant,namely c.2443C>T(p.Arg815*),which has not been reported previously in the domestic or foreign literature.CONCLUSION Pathogenic ABCC2 mutations play an important role in the diagnosis of DJS,especially in patients with atypical presentations.Currently,NGS is used in the routine analysis of DJS cases and such tests of further cases will better illuminate the relationship between various genotypes and phenotypes of DJS.
文摘Previous studies have shown that leak electro ns in cusped field thrusters can move along the channel axis to the anode after crossing the magnetic cusp on the exit.In this paper,a onedimensional fluid model is built along two typical electron paths to study the influence of leak electrons on the discharge characteristics of a cusped field thruster,considering the electron temperature equation.It is found that the frequencies of low-frequency oscillations increase with a decrease in the proportion of leak electrons,which is related to an increase in the ion speed in the channel.Simulation results show that the position of the peak electron temperature is near the magnetic cusp on the exit and the position of the peak electron density is located downstream from the middle magnetic tip.With a decrease in the proportion of the leak electrons,the peak electron temperature and peak electron density decrease and the position of the peak electron density moves away from the exit,which is related to a decrease in the potential fall on the exit and an increase in confinement of electrons to the middle magnetic cusp.
基金supported by the Special Fund for Agro-scientific Research in the Public Interest(No.201403047)Science Technology Department of Zhejiang Province(2015C02022)
文摘Background: A series of modified montmorillonites(Mt) including zinc-loaded Mt(Zn-Mt), copper-loaded Mt(Cu-Mt), copper/zinc-loaded Mt with different Cu/Zn ratio(Cu/Zn-Mt-1, Cu/Zn-Mt-2, Cu/Zn-Mt-3) were prepared by an ion-exchange reaction, and characterized using X-ray diffraction(XRD), fourier transformed infrared spectroscopy(FTIR) and transmission electron microscopy(TEM). The specific surface areas, antimicrobial activity and cytotoxicity of the modified Mt were investigated.Results: In the modified Mt, hydrated Cu ions and Zn ions were exchanged in the interlayer space of Mt and the particles were irregular shapes. The results showed that Cu/Zn-Mt enhanced antibacterial and antifungal activity compared with Zn-Mt and Cu-Mt possibly due to the synergistic effect between Cu and Zn. Among the Cu/Zn-Mt with different Cu/Zn raitos, Cu/Zn-Mt with a Cu/Zn ratio of 0.98 or 0.51 showed higher antimicrobial activity against gram-negative bacteria(Escherichia coli), gram-positive bacteria(Staphylococcus aureus), fungi(Candida albicans).Moreover, the antimicrobial activity of Cu/Zn-Mt was correlated with its specific surface area. Cytotoxicity studies on IPEC-J2 cell showed a slight cytotoxicity of Cu/Zn-Mt.Conclusions: The current data provide clear evidence that in terms of its antimicrobial activity and relatively low toxicity, the Cu/Zn-Mt holds great promise for applications in animal husbandry.
基金Supported by National Key R&D Program of China (No.2018YFC1314900 No.2018YFC1314902)+2 种基金Nantong “226 Project”Excellent Key Teachers in the “Qing Lan Project” of Jiangsu Colleges and UniversitiesJiangsu Students’ Platform for Innovation and Entrepreneurship Training Program (No.201910304108Y)
文摘AIM: To ensure the diagnostic value of computer aided techniques in diabetic retinopathy(DR) detection based on ophthalmic photography(OP). METHODS: PubM ed, EMBASE, Ei village, IEEE Xplore and Cochrane Library database were searched systematically for literatures about computer aided detection(CAD) in DR detection. The methodological quality of included studies was appraised by the Quality Assessment Tool for Diagnostic Accuracy Studies(QUADAS-2). Meta-Di Sc was utilized and a random effects model was plotted to summarize data from those included studies. Summary receiver operating characteristic curves were selected to estimate the overall test performance. Subgroup analysis was used to identify the efficiency of CAD in detecting DR, exudates(EXs), microaneurysms(MAs) as well as hemorrhages(HMs), and neovascularizations(NVs). Publication bias was analyzed using STATA. RESULTS: Fourteen articles were finally included in this Meta-analysis after literature review. Pooled sensitivity and specificity were 90%(95%CI, 85%-94%) and 90%(95%CI, 80%-96%) respectively for CAD in DR detection. With regard to CAD in EXs detecting, pooled sensitivity, specificity were 89%(95%CI, 88%-90%) and99%(95%CI, 99%-99%) respectively. In aspect of MAs and HMs detection, pooled sensitivity and specificity of CAD were 42%(95%CI, 41%-44%) and 93%(95%CI, 93%-93%) respectively. Besides, pooled sensitivity and specificity were 94%(95%CI, 89%-97%) and 87%(95%CI, 83%-90%) respectively for CAD in NVs detection. No potential publication bias was observed. CONCLUSION: CAD demonstrates overall high diagnostic accuracy for detecting DR and pathological lesions based on OP. Further prospective clinical trials are needed to prove such effect.
文摘Objective: The aim is to understand the status of rural medical waste management and problems and to make recommendations. Methods: The questionnaire survey, interviews and comparative analysis are used. Results: Compared with urban medical waste management, rural medical waste management is weaker in classification, unified recycle, disposals, protect measures of related personnel, regulations and policies of awareness. Conclusion: It is recommended to improve policies and regulations of rural medical waste management, strengthen rural infrastructures and facilities, improve supervision and innovates means of supervision.
基金Sponsored by the National Defense Basic Research Program(Grant No.A0920110016)
文摘The reasons for bringing surface accuracy error in ultra-precision grinding ceramic ball joint were analyzed,and the influences wheel position error and shaft run-out error on the ball joint surface accuracy were discussed.Through establishing three-dimensional grinding model,the mathematical relationship between the position error and surface accuracy was derived,and the distance from any point on spherical surface to the ideal center was calculated when position error existed,and a precise surface shape was got,and theoretical support was provided to improve the surface accuracy during the grinding process.Using self-developed ultraprecision grinding machine to do the ceramic ball grinding experiment,the surface accuracy PV value of ceramic spherical joint is 4.8μm.
文摘Due to medical waste’s infection and hazard, it can cause potential environmental and public health risks, so medical waste management is of great importance especially in developing countries. The objective of the study was to analyze and assess current status of medical waste management in the light of semi-structured interview in medical institutions and the medical waste disposal centre. As a medium-sized city of China and its respective nature, Xinxiang was selected as the case study. In order to significantly improve eco-efficiency of medical waste management (MWM) and minimize the environmental risks, this paper identified key factors determining the implementation of MWM on the basis of the local realities and situations of medical waste, and then an integrated MWM system was developed. Such the regulations should be improved;MWM database platform should be strengthened;unified coordination ability of the MWM should be developed;and a suitable rural recycling network should be set up.
基金supported by grants from the Yunnan Applied Basic Research Project(2013FB069)
文摘DEAR EDITOR Centenarians are a typical longevity model characterized by delayed onset of morbidity in age-related diseases such as cancer, cardiovascular disease, dementia, and stroke (Andersen et al, 2012). Though there may be a number of underlying mechanisms behind this longevity, curiously it seems that the survival advantage persists in their offspring (Terry et al, 2003), suggesting a potentially important role for genetic factors. Previous studies suggested that the heritability of human longevity may be ~25% (Herskind et al, 1996; Mcgue et al, 1993), whicih is consistent with other studies on model organisms that identified several longevity-related genes, such as age-l, daf-2, daf-16, and sir-2 (Friedman & Johnson, 1988; Kenyon et al, 1993; Lin et al, 1997; Tissenbaum & Guarente, 2001). Likewise, several studies have reported the existence of many mutations related to human longevity (Holstege et al, 2014; Sebastiani et al, 2012).
基金supported by National Key Research and Development Program of China(2022YFC2702702,2021YFC2700901)the National Natural Science Foundation of China(81971441,82171607,32000584)+3 种基金the University Outstanding Young Talents Support Program(gxyq2021174)Non-profit Central Research Institute Fund of Chinese Academy of Medical Sciences(2019PT310002)Anhui Provincial Natural Science Foundation(2208085Y31)the Natural Science Foundation of Jiangsu Province(BK20230004).
文摘The complexities of energy transfer mechanisms in the flagella of mammalian sperm flagella have been intensively investigated and demonstrate significant diversity across species.Enzymatic shuttles,particularly adenylate kinase(AK)and creatine kinase(CK),are pivotal in the efficient transfer of intracellular ATP,showing distinct tissue-and species-specificity.Here,the expression profiles of AK and CK were investigated in mice and found to fall into four subgroups,of which Subgroup III AKs were observed to be unique to the male reproductive system and conserved across chordates.Both AK8 and AK9 were found to be indispensable to male reproduction after analysis of an infertile male cohort.Knockout mouse models showed that AK8 and AK9 were central to promoting sperm motility.Immunoprecipitation combined with mass spectrometry revealed that AK8 and AK9 interact with the radial spoke(RS)of the axoneme.Examination of various human and mouse sperm samples with substructural damage,including the presence of multiple RS subunits,showed that the head of radial spoke 3 acts as an adapter for AK9 in the flagellar axoneme.Using an ATP probe together with metabolomic analysis,it was found that AK8 and AK9 cooperatively regulated ATP transfer in the axoneme,and were concentrated at sites associated with energy consumption in the flagellum.These findings indicate a novel function for RS beyond its structural role,namely,the regulation of ATP transfer.In conclusion,the results expand the functional spectrum of AK proteins and suggest a fresh model regarding ATP transfer within mammalian flagella.
基金This study was supported by the National Key Research and Development Program of China(2021YFC2701400 and 2023YFC2705600)the National Natural Science Foundation of China(32288101,32100480,32370654,82271639,32322017,and32200485).
文摘Oligoasthenoteratozoospermia is an important factor affecting male fertility and has been found to be associated with genetic factors.However,there are stll a proportion of oligoasthenoteratozoospermia cases that cannot be explained by known pathogenic genetic variants.Here,we perform genetic analyses and identify bi-allelic loss-of-function variants of MFSD6L from an oligoasthenoteratozoospermia-affected family.Mfsd6l knock-out male mice also present male subfertility with reduced sperm concentration,motility,and deformed acrosomes.Further mechanistic analyses reveal that MFsD6L,as an acrosome membrane protein,plays an important role in the formation of acrosome by interacting with the inner acrosomal membrane protein SPACA1.Moreover,poor embryonic development is consistently observed after intracytoplasmic sperm injection treatment using spermatozoa from the MFSD6L-deficient man and male mice.Collectively,our findings reveal that MFSD6L is required for the anchoring of sperm acrosome and head shaping.The deficiency of MFsD6L affects male fertility and causes oligoasthenoter-atozoospermia in humans and mice.
基金supported by the National Natural Science Foundation of China(Grant No.31922050)the Fund of the Jilin Province Science and Technology Development Project(Grant No.20220101273JC)+1 种基金the Fundamental Research Funds for the Central Universities(Grant Nos.2412023QD026 and 2412023YQ002)the Special Foundation for National Science and Technology Basic Research Program of China(Grant No.2021FY100301).
文摘Anti-predation strategies are critical to animal survival and are fundamental to deciphering predator–prey interactions.As an important defense strategy,sensory predator detection(such as through acoustic and visual cues)enables animals to assess predation risk and execute predator-avoidance behavior;however,there are limited studies on the anti-predation behavior of nocturnal animals.The prey of bats provides an excellent representative system for examining the anti-predation behavior of nocturnal animals.Here,we broadcasted different types of echolocation calls of the bird-eating bat Ia io to two wild passerine birds,namely,Zosterops japonicus and Sinosuthora webbiana,that are preyed upon by I.io,and presented the birds with individual bats under different light intensities.The results showed that both bird species were able to perceive the low-frequency audible portion of the bats’echolocation calls;however,they did not exhibit escape responses to the acoustic stimuli.In the dark and under moonlit conditions,both bird species were unable to respond to active bats at close range and the birds only exhibited evasive flight behavior when bats approached or touched them.These results suggest that nocturnal passerine birds may not be able to use acoustic or visual cues to detect bats and adopt evasive maneuvers to avoid predation.This work suggests that bat predation pressure may not elicit primary predator-avoidance responses in nocturnal passerine birds.The results provide new insights into the anti-predation behavior of nocturnal animals.
基金supported by the Construction Project for Shanxi Key Laboratory of Germplasm Resources Innovation and Utilization of Vegetables and Flowers(202204010931019)the Reward Fund for PhDs and Postdoctors of Shanxi Province(SXBYKY2022004)the Fund for High-level Talents of Shanxi Agricultural University(2021XG010).
文摘Gerbera(Gerbera hybrida),a major fresh cut flower crop,is very susceptible to root rot disease.Although plant defensins(PDFs),a major group of plant antimicrobial peptides,display broad-spectrum antifungal and antibacterial activities,PDF genes in gerbera have not been systematically characterized.Here,we identified and cloned nine PDF genes from gerbera and divided them into two classes based on phylogenetic analysis.Most Class Ⅰ GhPDF genes were highly expressed in petioles,whereas all Class Ⅱ GhPDF genes were highly expressed in roots.Phytophthora cryptogea inoculation strongly upregulated all Class II GhPDF genes in roots and upregulated all Class Ⅰ GhPDF genes in petioles.Transient overexpression of GhPDF1.5 and GhPDF2.4 inhibited P.cryptogea infection in tobacco(Nicotiana benthamiana)leaves.Transient overexpression of GhPDF2.4,but not GhPDF1.5,significantly upregulated ACO and LOX gene expression in tobacco leaves,indicating that overexpressing GhPDF2.4 activated the jasmonic acid/ethylene defense pathway and that the two types of GhPDFs have different modes of action.Prokaryotically expressed recombinant GhPDF2.4 inhibited mycelial growth and delayed the hyphal swelling of P.cryptogea,in vitro,indicating that GhPDF2.4 is a morphogenetic defensin.Moreover,the addition of GhPDF2.4 to plant culture medium alleviated the root rot symptoms of in vitro-grown gerbera seedlings and greatly reduced pathogen titer in P.cryptogea-inoculated gerbera roots in the early stages of treatment.Our study provides a basis for the use of GhPDFs,especially GhPDF2.4,for controlling root rot disease in gerbera.