Sub-gingival anaerobic pathogens can colonize an implant surface to compromise osseointegration of dental implants once the soft tissue seal around the neck of an implant is broken. In vitro evaluations of implant mat...Sub-gingival anaerobic pathogens can colonize an implant surface to compromise osseointegration of dental implants once the soft tissue seal around the neck of an implant is broken. In vitro evaluations of implant materials are usually done in monoculture studies involving either tissue integration or bacterial colonization. Co-culture models, in which tissue cells and bacteria battle simultaneously for estate on an implant surface, have been demonstrated to provide a better in vitro mimic of the clinical situation. Here we aim to compare the surface coverage by U2OS osteoblasts cells prior to and after challenge by two anaerobic sub-gingival pathogens in a co-culture model on differently modified titanium （Ti）, titanium-zirconium （TiZr） alloys and zirconia surfaces. Monoculture studies with either U2OS osteoblasts or bacteria were also carried out and indicated significant differences in biofilm formation between the implant materials, but interactions with U2OS osteoblasts were favourable on all materials. Adhering U2OS osteoblasts cells, however, were significantly more displaced from differently modified Ti surfaces by challenging sub-gingival pathogens than from TiZr alloys and zirconia variants. Combined with previous work employing a co-culture model consisting of human gingival fibroblasts and supra-gingival oral bacteria, results point to a different material selection to stimulate the formation of a soft tissue seal as compared to preservation of osseointegration under the unsterile conditions of the oral cavity.展开更多
【Objective】This study aimed to establish a quintuple PCR method for rapid and simultaneous detection of Ralstonia solanacearum,Fusarium spp.,Pectobacterium spp.,Enterobacter spp.,and Pythium spp.,which provided tech...【Objective】This study aimed to establish a quintuple PCR method for rapid and simultaneous detection of Ralstonia solanacearum,Fusarium spp.,Pectobacterium spp.,Enterobacter spp.,and Pythium spp.,which provided technical support for early diagnosis of various soil-borne diseases on ginger.【Method】For five types of soil-borne pathogens causing ginger bacterial wilt and rhizome rot,specific primer combinations were designed and screened,the optimal quintuple reaction system was established by exploring optimal primer concentrations,annealing temperature,and sensitivity,and was applied to detect field plant samples to verify its utility.【Result】Specific primers pairs Rs1F/Rs1R,En1F/En1R,and Py1F/Py1R were designed according to flic gene of Ralstonia solanacearum,rpoB gene of Enterobacter spp.,and 18S rDNA of Pythium spp.,and combined with reported Fusarium spp.specific primers Fu3/Fu4 and specific primers 23SPecF/23SPecR of Pectobacterium spp.,a quintuple PCR reaction system for ginger soil-borne pathogens has been established(25.00μL):above primer dosage was 1.20,0.20,0.60,1.60,and 0.15μL respectively;2×PCR Mix 12.50μL;DNA templates of different pathogens were 1.00μL each;added ddH_(2)O to 25.00μL.Annealing temperature was optimized to 55.4℃.The specific fragments with sizes of 516,370,266,207,and 159 bp could be amplified simultaneously in the established quintuple PCR system,and the detection limit of this system for Ralstonia solanacearum,Enterobacter spp.and Pythium spp.reached 10^(-1)pg/μL,for Fusarium spp.and Pectobacterium spp.was 1 pg/μL,and for detecting five pathogens simultaneously was 10^(3)pg/μL.The multiplex PCR system established in this study could successfully detect the diseased plant samples from the field.【Conclusion】The quintuple PCR system established is able to rapid ly and accurately detect Ralstonia solanacearum,Fusarium spp.,Pectobacterium spp.,Enterobacter spp.,and Pythium spp.,which provides a useful tool for timely diagnosis and epidemic monitoring of various soil-borne diseases of ginger.展开更多
Root rot is a prevalent soil-borne fungal disease in citrus.Citron C-05(Citrus medica)stands out as a germplasm within Citrus spp.due to its complete resistance to citrus canker and favorable characteristics such as s...Root rot is a prevalent soil-borne fungal disease in citrus.Citron C-05(Citrus medica)stands out as a germplasm within Citrus spp.due to its complete resistance to citrus canker and favorable characteristics such as single embryo and easy rooting.However,Citron C-05 was found to be highly susceptible to root rot during cultivation,with the specific pathogens previously unknown.In this study,four candidate fungal species were isolated from Citron C-05 roots.Sequence analysis of ITS,EF-1a,RPB1,and RPB2 identified two Fusarium solani strains,Rr-2 and Rr-4,as the candidates causing root rot in Citron C-05.Resistance tests showed these two pathogens increased root damage rate from 10.30%to 35.69%in Citron C-05,sour orange(Citrus aurantium),sweet orange(Citrus sinensis)and pummelo(Citrus grandis).F.solani exhibited the weak pathogenicity towards trifoliate orange(Poncirus trifoliata).DAB staining revealed none of reddish-brown precipitation in the four susceptible citrus germplasm after infection with F.solani,while trifoliate orange exhibited significant H2O2 accumulation.Trypan blue staining indicated increased cell death in the four susceptible citrus germplasm following infection with these two pathogens but not in trifoliate orange.These findings provide a comprehensive understanding of citrus root rot and support future research on the mechanisms of root rot resistance in citrus.展开更多
Reductive soil disinfestation(RSD)is commonly employed for soil remediation in greenhouse cultivation.However,its influence on antibiotic resistance genes(ARGs)in soil remains uncertain.This study investigated the dyn...Reductive soil disinfestation(RSD)is commonly employed for soil remediation in greenhouse cultivation.However,its influence on antibiotic resistance genes(ARGs)in soil remains uncertain.This study investigated the dynamic changes in soil communities,potential bacterial pathogens,and ARG profiles under various organicmaterial treatments during RSD,including distillers’grains,potato peel,peanut vine,and peanut vine combined with charcoal.Results revealed that applying diverse organic materials in RSD significantly altered bacterial community composition and diminished the relative abundance of potential bacterial pathogens(P<0.05).The relative abundance of high-risk ARGs decreased by 10.7%-30.6%after RSD treatments,the main decreased ARG subtypeswere AAC(3)_Via,dfrA1,ErmB,lnuB,aadA.Actinobacteria was the primary host of ARGs and was suppressed by RSD.Soil physicochemical properties,such as total nitrogen,soil pH,total carbon,were crucial factors affecting ARG profiles.Our findings demonstrated that RSD treatment inhibited pathogenic bacteria and could be an option for reducing high-risk ARG proliferation in soil.展开更多
The sustainable development of aquaculture industry is deeply constrained by pathogens and diseases,and traditional detection methods are difficult to adapt to the needs of intensive aquaculture due to low efficiency ...The sustainable development of aquaculture industry is deeply constrained by pathogens and diseases,and traditional detection methods are difficult to adapt to the needs of intensive aquaculture due to low efficiency and insufficient sensitivity.This article reviews the progress of rapid detection technology for aquatic pathogens based on molecular biology,immunology,biosensors,etc.,and analyzes the application value of innovative methods such as isothermal amplification and CRISPR.This technology injects core momentum into the new quality productivity of fisheries through early and precise identification of pathogens:reducing aquaculture losses to improve resource efficiency,promoting the transformation of aquaculture models to data-driven,ensuring the safety of aquatic products to enhance the competitiveness of the industry chain.The current technology has shortcomings such as lagging standardization,weak on-site anti-interference ability,and insufficient recognition of new pathogens.In the future,we need to focus on technological integration and innovation,intelligent upgrading,and standardization construction,promote technology from laboratories to industrial applications,and provide continuous support for the high-quality development of fisheries.展开更多
In order to ensure food safety,controlling foodborne pathogen contamination is of utmost importance.Growing apprehensions regarding the safety of synthetic antimicrobials,due to their adverse health effects,have promp...In order to ensure food safety,controlling foodborne pathogen contamination is of utmost importance.Growing apprehensions regarding the safety of synthetic antimicrobials,due to their adverse health effects,have prompted a search for alternative options.Plant natural products(PNPs)with antimicrobial activity are being explored as a viable alternative.Among the various antimicrobial natural products studied,plant essential oils,plant flavonoids,plant polyphenols,plant polysaccharides,and plant antimicrobial peptides have been identified as potential candidates.PNPs demonstrate a diverse array of antimicrobial mechanisms,encompassing cell wall and membrane damage,interference with genetic replication,disruption of energy metabolism,and induction of oxidative stress at the single-cell level,as well as inhibition of biofilm formation and quorum sensing at the population level.Certain PNPs have been harnessed as natural antimicrobial agents for the food preservation.The utilization of encapsulation technology proves to be an effective strategy in protecting PNPs,thereby ensuring good antimicrobial efficacy,enhanced dispersibility,and controlled release within food products.The utilization of nanoemulsions,nanoliposomes,edible packaging,electrospun nanofibers,and microcapsules formed by encapsulation has enriched the ways in which PNPs can be applied in food preservation.Although PNPs have great potential in food preservation,their widespread application in the food industry is currently constrained by factors such as production costs,safety concerns,and legal considerations.Chemical synthesis and biosynthesis pathways offer viable strategies for reducing the cost of producing PNPs,and ongoing efforts to assess safety and improve regulatory frameworks are likely to facilitate the broader adoption of PNPs in food preservation practices.This article provides an overview of the main types of PNPs with antimicrobial activity and their properties,focusing on their mechanisms of action.Additionally,it summarizes the use of PNPs in food preservation and discusses the characteristics and applications of different encapsulation technologies.Lastly,the paper briefly analyzes current limitations and proposes potential future trends for this field.展开更多
Respiratory infections are associated with high morbidity and mortality and are a major global health problem[1].Acute respiratory infections are caused by multiple respiratory pathogens,including viruses and bacteria...Respiratory infections are associated with high morbidity and mortality and are a major global health problem[1].Acute respiratory infections are caused by multiple respiratory pathogens,including viruses and bacteria.Viral-bacterial co-infections,which have become increasingly common and a global concern,can lead to substantial complications,causing higher morbidity and adverse prognosis[2].Previous studies have reported low positive detection rates of targeted pathogens related to acute respiratory infections,owing to the limited number of detected pathogens and variations in the sensitivity of diagnostic methods[3-4].Low positive detection rates may impede our understanding of respiratory pathogen characteristics and hamper the development of precise treatment and prevention strategies.展开更多
The implementation of multiple pathogen testing is essential for a rapid response to future outbreaks and for reducing disease transmission.This study introduces a 96-channel microfluidic chip,fabricated through a mol...The implementation of multiple pathogen testing is essential for a rapid response to future outbreaks and for reducing disease transmission.This study introduces a 96-channel microfluidic chip,fabricated through a molding process,which enables the batch detection of pathogens.It explores the rapid lysis and elution processes of pathogens within the microfluidic chips to ensure that nucleic acid extraction,elution,and amplification are completed entirely within the chip.This chip can extract nucleic acids from samples in just 10 min,achieving an extraction efficiency comparable to that of traditional in-tube methods.An oil phase is pre-loaded into the chip to effectively prevent aerosol contamination.This approach allows for the simultaneous detection of 21 common respiratory pathogens,with a detection limit of 10 copies per reaction.Furthermore,applications involving clinical samples demonstrate significant practicality.Compared to many traditional in-tube pathogen detection methods and molecular biology technologies that utilize microfluidic chips,this detection chip not only enables simultaneous detection of multiple pathogens but also demonstrates high sensitivity.展开更多
Plant-parasitic nematodes(PPNs)(Meloidogyne sp.,Globodera sp.,and Pratylenchus sp.)and fungi are two of the most economically important groups of organisms affecting agricultural productivity worldwide.The interaction...Plant-parasitic nematodes(PPNs)(Meloidogyne sp.,Globodera sp.,and Pratylenchus sp.)and fungi are two of the most economically important groups of organisms affecting agricultural productivity worldwide.The interactions among PPNs,biocontrol fungi,and soil ecosystem can significantly impact plant health,disease management,and ecosystem functioning.We aimed to provide a comprehensive overview of the complex relationships between PPNs and biocontrol fungi,including pathogenic and biocontrol interactions.We summarized the molecular and ecological mechanisms underlying these interactions,highlighting the key players,signaling pathways,and environmental factors that influence the interactions.We also reviewed current knowledge on fungus-based biocontrol strategies against PPNs,including the development of novel management approaches.Furthermore,we explored the prospects of nematode-fungus interactions in agriculture,including the potential applications and technologies,precision agriculture,and integrated pest management approaches.This review highlights the need for further research on nematode-fungus interactions and their impact on plant infection and productivity,with an emphasis on the development of sustainable and effective strategies for managing PPNs and enhancing plant health in agricultural ecosystems.展开更多
Neurodegenerative diseases are a class of disorders with the gradual loss of the central nervous system and peripheral nervous system.Neurodegenerative diseases manifest primarily as cognitive and behavioral disorders...Neurodegenerative diseases are a class of disorders with the gradual loss of the central nervous system and peripheral nervous system.Neurodegenerative diseases manifest primarily as cognitive and behavioral disorders that adversely affect the lives of millions of people worldwide.Therefore,it is necessary to elucidate the mechanism of neurodegenerative diseases further and find effective new therapies.In recent years,increasing evidence has shown that the immune system plays a significant role in the pathophysiology of neurodegenerative diseases and regulates this process.The central and peripheral immune systems exert different roles in the disease progression.The development of neurodegenerative diseases is influenced by interactions between them.This review focuses on how the immune system,including microglia mediated nucleotide-binding oligomerization domain-like receptor protein 3 inflammation activation and T cell-mediated neuroinflammation,interactions with neurodegenerative diseases by modulating protein aggregation and blood-brain barrier permeability.Besides,we gave particular attention to glial cell-centered multicellular interactions and the inflammatory signaling pathway.Insight into the immune system’s functions and cellular interactions is essential for progressing disease research.In addition,the functions and mechanisms of these immune cells also suggest new ideas and targets for treatment.Therefore,this review summarizes some of the existing treatment strategies for amyloid-beta,tau,neuroinflammation,α-synuclein,associated microbiota,immune modulation,and neural injury repair.In addition,this review summarizes and compares animal models of different common neurodegenerative diseases and clinical research progress.In view of the current research status,new research directions and suggestions are proposed.展开更多
NADC34-like porcine reproductive and respiratory syndrome virus(PRRSV),which first appeared in China in 2017,is currently one of the main epidemic strains in China.In this study,we found that a new variant of NADC34-l...NADC34-like porcine reproductive and respiratory syndrome virus(PRRSV),which first appeared in China in 2017,is currently one of the main epidemic strains in China.In this study,we found that a new variant of NADC34-like PRRSV evolved,named the L1A variant.The phylogenetics,epidemic status,and pathogenicity of the LA variants were subsequently comprehensively evaluated.Based on the results of the ORF5 phylogenetic analysis,the L1A variants were classified as NADC34-like PPRSV.All the strains had the same discontinuous 131-aa deletion in the NSP2 region(similar to that in the NADC30).Recombination analysis revealed that the L1A variants were recombinant viruses that contained an NADC30-like PRRSV skeleton,a nonstructural protein-encoding gene region obtained in part from JXA1-like PRRSV and a ORF2-ORF6 gene region partly obtained from NADC34-like PRRSV and that exhibited similar recombination patterns.We successfully isolated the L1A variant TZJ2756 from PAMs and Marc-145 cells.In animal experiments,TZJ2756 exhibited moderate pathogenicity in piglets,causing obvious clinical symptoms,namely,persistent fever,significantly reduced body weight,interstitial edema and severe interstitial pneumonia in the lungs,and prolonged high-load viremia.L1A variants have been detected in at least 12 provinces in China and share many similar epidemiological characteristics with the American L1C variant.This research will enhance our understanding of the prevalence of L1A variants and furnish valuable data for the ongoing monitoring of NADC34-like PRRSV in China.展开更多
Staphylococcus aureus(S.aureus)is the third most common pathogen causing 10.6%of bacterial foodborne illnesses in China in 2021[1].Heat-stable Staphylococcal Enterotoxins(SEs)produced by S.aureus are the main contribu...Staphylococcus aureus(S.aureus)is the third most common pathogen causing 10.6%of bacterial foodborne illnesses in China in 2021[1].Heat-stable Staphylococcal Enterotoxins(SEs)produced by S.aureus are the main contributors to staphylococcal food poisoning(SFP),causing vomiting,diarrhea,abdominal pain,headache,muscle cramps,and other acute gastroenteritis symptoms.More than 25 SEs and staphylococcal enterotoxin-like toxins(SE/s)have been described and which together comprise a superfamily of pyrogenic toxin superantigens(SAgs)[2].展开更多
Multiple sclerosis is a severe autoimmune disorder that is mainly mediated by pathogenic cluster of CD4^(+)T cell subsets.Despite advancements in the management of multiple sclerosis,there is a critical need for more ...Multiple sclerosis is a severe autoimmune disorder that is mainly mediated by pathogenic cluster of CD4^(+)T cell subsets.Despite advancements in the management of multiple sclerosis,there is a critical need for more effective and safer treatments.In the present study,we administered Lycium barbarum glycopeptide to a mouse model of experimental autoimmune encephalomyelitis-an animal model of multiple sclerosis-and evaluated its effects on pathogenic CD4^(+)T cell activation both in vivo and in vitro.Lycium barbarum glycopeptide significantly mitigated the clinical severity of experimental autoimmune encephalomyelitis,as demonstrated by reduced demyelination and neuroinflammation.Moreover,Lycium barbarum glycopeptide treatment decreased the infiltration of peripheral leukocytes into the central nervous system and suppressed pro-inflammatory cytokine expression.Lycium barbarum glycopeptide also modulated pathogenic CD4^(+)T cell activation by inhibiting T helper 1/T helper 17 cell differentiation while promoting regulatory T cell expansion.Notably,no side effects were observed,suggesting the long-term safety and tolerability of Lycium barbarum glycopeptide.Furthermore,RNA sequencing data indicated that Lycium barbarum glycopeptide inhibits activator protein-1,an essential regulator of T cell activation and differentiation.This finding was supported by the reversal of T helper/T helper 17 cell response suppression upon AP-1 blockade.Collectively,these results highlight the potential of Lycium barbarum glycopeptide as an innovative therapeutic agent for CD4^(+)T cell-associated autoimmune or inflammatory diseases,such as multiple sclerosis.展开更多
The pathogens and opinion for antibiotic treatment in adult patients with 1-14 fecal white blood cells per high power field （WBC/HPF） of acute non-bloody diarrhea remain obscure. The study attempts to clarify it. St...The pathogens and opinion for antibiotic treatment in adult patients with 1-14 fecal white blood cells per high power field （WBC/HPF） of acute non-bloody diarrhea remain obscure. The study attempts to clarify it. Stool specimens of adult patients with acute non-bloody diarrhea and stool examination showing 1-14 fecal WBC/HPF were collected for bacterial culture and viral detection. Patients included in this study were 196 cases with mean age of （37.9±17.4） years and 42.3% was women. The bacterial and viral detection rates were 63 （32.1%） and 21 （10.7%）, respectively. Of the isolated pathogens, campylobacteria was present in 14 （22.0%） samples and was the most common bacteria and calicivirus was found in 10 （47.6%） samples and was the most common virus. Based on single pathogens, 46 cases were caused by invasive pathogens, 26 cases were caused by non-invasive pathogens. The body temperature was significantly higher in feverish patients caused by invasive pathogens than those caused by non-invasive pathogens （（38.44-0.7） ℃ vs （37.74-0.4） ℃, P = 0.002）. The probability of diarrhea caused by invasive pathogens was higher in patients with T〉38.4℃ than those with T_〈38.4℃ （RR = 1.5）. When T〉38.4℃ is used as the threshold for antibiotic treatment, the misuse rate of antibiotics would decrease from 26.9% to 3.8% （P = 0.021）. So T〉38.4 ℃ may be used as a possible reference value for antibiotic treatment in adult patients with 1-14 fecal WBC/HPF of acute non-bloody diarrhea.展开更多
[Objective] The aim of this study was to purify an antimicrobial protein from a biocontrol bacterium strain K2-1 and analyze its antimicrobial activity in vitro against some typical aquatic pathogens. [Method] The ant...[Objective] The aim of this study was to purify an antimicrobial protein from a biocontrol bacterium strain K2-1 and analyze its antimicrobial activity in vitro against some typical aquatic pathogens. [Method] The antimicrobial protein was ob- tained by using ammonium sulfate precipitation and Sephadex chromatography combined with hot water bath. The antimicrobial assay was conducted by means of agar diffusion technique, using Vibrio alginolyticus, Aeromonas hydrophila, Aeromonas. Sobria, Pseudomonas fluorescens, Vibrio Parahaemolyticus, Vibrio har- veyi and Vibrio anguillarum as test bacteria. [Result] Antimicrobial protein APK2 can be derived from fermentation broth of strain K2-1 and purified to the chromatogra- phy pure level by the methods provided, the final yield of the antimicrobial compo- nent is approximately 0.08%. This antimicrobial protein had a strong antimicrobial activity against the growth of most those bacteria. [Conclusion] The results show that APK2 could be a potential alternative to replace chemical antimicrobial agent in the control and prevention of aquatic diseases.展开更多
The importance of pyrimidines lies in the fact that they are structural components of a broad spectrum of key molecules that participate in diverse cellular functions, such as synthesis of DNA, RNA, lipids, and carboh...The importance of pyrimidines lies in the fact that they are structural components of a broad spectrum of key molecules that participate in diverse cellular functions, such as synthesis of DNA, RNA, lipids, and carbohydrates. Pyrimidine metabolism encompasses all enzymes involved in the synthesis, degradation, salvage, interconversion and transport of these molecules. In this review, we summarize recent publications that document how pyrimidine metabolism changes under a variety of conditions, including, when possible, those studies based on techniques of genomics, transcriptomics, proteomics, and metabolomics. First, we briefly look at the dynamics of pyrimidine metabolism during nonpathogenic cellular events. We then focus on changes that pathogen infections cause in the pyrimidine metabolism of their host. Next, we discuss the effects of antimetabolites and inhibitors, and finally we consider the consequences of genetic ma- nipulations, such as knock-downs, knock-outs, and knock-ins, of pyrimidine enzymes on pyrimidine metabolism in the cell.展开更多
The effects of O3/Cl2 disinfection on corrosion and the growth of opportunistic pathogens in drinking water distribution systems were studied using annular reactors （ARs）. The corrosion process and most probable num...The effects of O3/Cl2 disinfection on corrosion and the growth of opportunistic pathogens in drinking water distribution systems were studied using annular reactors （ARs）. The corrosion process and most probable number （MPN） analysis indicated that the higher content of iron-oxidizing bacteria and iron-reducing bacteria in biofilms of the AR treated with O3/Cl2 induced higher Fe304 formation in corrosion scales. These corrosion scales became more stable than the ones that formed in the AR treated with Cl2 alone. O3/Cl2 disinfection inhibited corrosion and iron release efficiently by changing the content of corrosion-related bacteria. Moreover, ozone disinfection inactivated or damaged the opportunistic pathogens due to its strong oxidizing properties. The damaged bacteria resulting from initial ozone treatment were inactivated by the subsequent chlorine disinfection. Compared with the AR treated with Cl2 alone, the opportunistic pathogens M. auium and L. pneumophila were not detectable in effluents of the AR treated with O3/Cl2, and decreased to （4.60 ± 0.14） and （3.09 ± 0.12） loglo （gene copies/g corrosion scales） in biofilms, respectively. The amoeba counts were also lower in the AR treated with O3/Cl2. Therefore, O3/Cl2 disinfection can effectively control opportunistic pathogens in effluents and biofilms of an AR used as a model for a drinking water distribution system.展开更多
The emergence and prevalence of antibiotic resistance genes(ARGs) and pathogens in the environment are serious global health concern. However, information about the occurrence of ARGs and pathogens in recreational wat...The emergence and prevalence of antibiotic resistance genes(ARGs) and pathogens in the environment are serious global health concern. However, information about the occurrence of ARGs and pathogens in recreational water is still limited. Accordingly, we investigated the occurrence of six ARGs and human pathogens in three recreational lakes, and the correlations between ARGs and one mobile genetic element(intI1) were analyzed. The quantitative PCR results showed that the concentration of ARGs ranged from 4.58 × 10~0 to 5.0 × 10~5 copies/mL in water and from 5.78 × 10~3 to 5.89 × 10~8 copies/g dry weight(dw)in sediment. Sul1 exhibited the highest level among the five quantifiable ARGs. The concentrations of sul1, bla_(-TEM), and tetX exhibited significant positive correlations with intI1(p < 0.05), indicating that intI1 may be involved in their proliferation. The detection frequencies of ARGs ranged from 75%–10~0%, indicating the prevalence of these risks in this region. The concentration of Escherichia coli, Aeromonas spp., Mycobacterium avium,Pseudomonas aeruginosa, and Salmonella enterica ranged from 10~3 to 10~5 copies/10~0 mL in water and 10~4–10~6 copies/g dw in sediment. In total, 25% of the samples harbored all pathogen genes, indicating the prevalence of these pathogens in recreational lakes.Furthermore, the next-generation sequencing results showed that 68 genera of pathogens were present, among which Aeromonas, Mycobacterium, and Pseudomonas were the dominant ones in this region, posing a considerable potential health risk to public health. Overall, the widespread distribution of ARGs and pathogens underscores the need to better monitor and mitigate their propagation in recreational lakes and the associated risks to human health.展开更多
Plant pathogens have evolved numerous strategies to obtain nutritive materials from their host, and plants in turn have evolved the preformed physical and chemical barriers as well as sophisticated two-tiered immune s...Plant pathogens have evolved numerous strategies to obtain nutritive materials from their host, and plants in turn have evolved the preformed physical and chemical barriers as well as sophisticated two-tiered immune system to combat pathogen attacks. Genetically, plant resistance to pathogens can be divided into qualitative and quantitative disease resistance, conditioned by major gene（s） and multiple genes with minor effects, respectively. Qualitative disease resistance has been mostly detected in plant defense against biotrophic pathogens, whereas quantitative disease resistance is involved in defense response to all plant pathogens, from biotrophs, hemibiotrophs to necrotrophs. Plant resistance is achieved through interception of pathogen-derived effectors and elicitation of defense response. In recent years, great progress has been made related to the molecular basis underlying host--pathogen interactions. In this review, we would like to provide an update on genetic and molecular aspects of plant resistance to pathogens.展开更多
文摘Sub-gingival anaerobic pathogens can colonize an implant surface to compromise osseointegration of dental implants once the soft tissue seal around the neck of an implant is broken. In vitro evaluations of implant materials are usually done in monoculture studies involving either tissue integration or bacterial colonization. Co-culture models, in which tissue cells and bacteria battle simultaneously for estate on an implant surface, have been demonstrated to provide a better in vitro mimic of the clinical situation. Here we aim to compare the surface coverage by U2OS osteoblasts cells prior to and after challenge by two anaerobic sub-gingival pathogens in a co-culture model on differently modified titanium （Ti）, titanium-zirconium （TiZr） alloys and zirconia surfaces. Monoculture studies with either U2OS osteoblasts or bacteria were also carried out and indicated significant differences in biofilm formation between the implant materials, but interactions with U2OS osteoblasts were favourable on all materials. Adhering U2OS osteoblasts cells, however, were significantly more displaced from differently modified Ti surfaces by challenging sub-gingival pathogens than from TiZr alloys and zirconia variants. Combined with previous work employing a co-culture model consisting of human gingival fibroblasts and supra-gingival oral bacteria, results point to a different material selection to stimulate the formation of a soft tissue seal as compared to preservation of osseointegration under the unsterile conditions of the oral cavity.
基金National Natural Science Foundation of China(32270237)Guangxi Key Research and Development Plan Project(Guike AB21238002)Basic Scientific Research Project of Guangxi Academy of Agricultural Sciences(Guinongke 2024YP082)。
文摘【Objective】This study aimed to establish a quintuple PCR method for rapid and simultaneous detection of Ralstonia solanacearum,Fusarium spp.,Pectobacterium spp.,Enterobacter spp.,and Pythium spp.,which provided technical support for early diagnosis of various soil-borne diseases on ginger.【Method】For five types of soil-borne pathogens causing ginger bacterial wilt and rhizome rot,specific primer combinations were designed and screened,the optimal quintuple reaction system was established by exploring optimal primer concentrations,annealing temperature,and sensitivity,and was applied to detect field plant samples to verify its utility.【Result】Specific primers pairs Rs1F/Rs1R,En1F/En1R,and Py1F/Py1R were designed according to flic gene of Ralstonia solanacearum,rpoB gene of Enterobacter spp.,and 18S rDNA of Pythium spp.,and combined with reported Fusarium spp.specific primers Fu3/Fu4 and specific primers 23SPecF/23SPecR of Pectobacterium spp.,a quintuple PCR reaction system for ginger soil-borne pathogens has been established(25.00μL):above primer dosage was 1.20,0.20,0.60,1.60,and 0.15μL respectively;2×PCR Mix 12.50μL;DNA templates of different pathogens were 1.00μL each;added ddH_(2)O to 25.00μL.Annealing temperature was optimized to 55.4℃.The specific fragments with sizes of 516,370,266,207,and 159 bp could be amplified simultaneously in the established quintuple PCR system,and the detection limit of this system for Ralstonia solanacearum,Enterobacter spp.and Pythium spp.reached 10^(-1)pg/μL,for Fusarium spp.and Pectobacterium spp.was 1 pg/μL,and for detecting five pathogens simultaneously was 10^(3)pg/μL.The multiplex PCR system established in this study could successfully detect the diseased plant samples from the field.【Conclusion】The quintuple PCR system established is able to rapid ly and accurately detect Ralstonia solanacearum,Fusarium spp.,Pectobacterium spp.,Enterobacter spp.,and Pythium spp.,which provides a useful tool for timely diagnosis and epidemic monitoring of various soil-borne diseases of ginger.
基金supported by Joint Funds of the National Natural Science Foundation of China(Grant No.U21A20228).
文摘Root rot is a prevalent soil-borne fungal disease in citrus.Citron C-05(Citrus medica)stands out as a germplasm within Citrus spp.due to its complete resistance to citrus canker and favorable characteristics such as single embryo and easy rooting.However,Citron C-05 was found to be highly susceptible to root rot during cultivation,with the specific pathogens previously unknown.In this study,four candidate fungal species were isolated from Citron C-05 roots.Sequence analysis of ITS,EF-1a,RPB1,and RPB2 identified two Fusarium solani strains,Rr-2 and Rr-4,as the candidates causing root rot in Citron C-05.Resistance tests showed these two pathogens increased root damage rate from 10.30%to 35.69%in Citron C-05,sour orange(Citrus aurantium),sweet orange(Citrus sinensis)and pummelo(Citrus grandis).F.solani exhibited the weak pathogenicity towards trifoliate orange(Poncirus trifoliata).DAB staining revealed none of reddish-brown precipitation in the four susceptible citrus germplasm after infection with F.solani,while trifoliate orange exhibited significant H2O2 accumulation.Trypan blue staining indicated increased cell death in the four susceptible citrus germplasm following infection with these two pathogens but not in trifoliate orange.These findings provide a comprehensive understanding of citrus root rot and support future research on the mechanisms of root rot resistance in citrus.
基金supported by the Key Research and Development Program of Shandong Province,China(No 2021CXGC010803)Pan’an County Chinese Medicine Industry Project(No.PZYF202103).
文摘Reductive soil disinfestation(RSD)is commonly employed for soil remediation in greenhouse cultivation.However,its influence on antibiotic resistance genes(ARGs)in soil remains uncertain.This study investigated the dynamic changes in soil communities,potential bacterial pathogens,and ARG profiles under various organicmaterial treatments during RSD,including distillers’grains,potato peel,peanut vine,and peanut vine combined with charcoal.Results revealed that applying diverse organic materials in RSD significantly altered bacterial community composition and diminished the relative abundance of potential bacterial pathogens(P<0.05).The relative abundance of high-risk ARGs decreased by 10.7%-30.6%after RSD treatments,the main decreased ARG subtypeswere AAC(3)_Via,dfrA1,ErmB,lnuB,aadA.Actinobacteria was the primary host of ARGs and was suppressed by RSD.Soil physicochemical properties,such as total nitrogen,soil pH,total carbon,were crucial factors affecting ARG profiles.Our findings demonstrated that RSD treatment inhibited pathogenic bacteria and could be an option for reducing high-risk ARG proliferation in soil.
基金supported by the National Modern Agricultural Industry Technology System(CARS-45-33)Innovation Team of Tianjin Freshwater Aquaculture Industry Technology System(ITTFRS2021000-002,ITTFRS2021000-001)+1 种基金Tianjin Science and Technology Plan Project(24KPHDRC00280,24ZYCGSN00250,23YDTPJC00420)the Open Fund Project of Key Laboratory of Ocean Observation Technology,MNR(No.2023klootA03).
文摘The sustainable development of aquaculture industry is deeply constrained by pathogens and diseases,and traditional detection methods are difficult to adapt to the needs of intensive aquaculture due to low efficiency and insufficient sensitivity.This article reviews the progress of rapid detection technology for aquatic pathogens based on molecular biology,immunology,biosensors,etc.,and analyzes the application value of innovative methods such as isothermal amplification and CRISPR.This technology injects core momentum into the new quality productivity of fisheries through early and precise identification of pathogens:reducing aquaculture losses to improve resource efficiency,promoting the transformation of aquaculture models to data-driven,ensuring the safety of aquatic products to enhance the competitiveness of the industry chain.The current technology has shortcomings such as lagging standardization,weak on-site anti-interference ability,and insufficient recognition of new pathogens.In the future,we need to focus on technological integration and innovation,intelligent upgrading,and standardization construction,promote technology from laboratories to industrial applications,and provide continuous support for the high-quality development of fisheries.
基金supported by the National Natural Science Foundation of China(32060520)Science and Technology Talents and Platform Program of Yunnan Province(202105AF150049)University Key Laboratory of Food Microbial Resources and Utilization in Yunnan Province(Yunjiaofa[2018]No.135).
文摘In order to ensure food safety,controlling foodborne pathogen contamination is of utmost importance.Growing apprehensions regarding the safety of synthetic antimicrobials,due to their adverse health effects,have prompted a search for alternative options.Plant natural products(PNPs)with antimicrobial activity are being explored as a viable alternative.Among the various antimicrobial natural products studied,plant essential oils,plant flavonoids,plant polyphenols,plant polysaccharides,and plant antimicrobial peptides have been identified as potential candidates.PNPs demonstrate a diverse array of antimicrobial mechanisms,encompassing cell wall and membrane damage,interference with genetic replication,disruption of energy metabolism,and induction of oxidative stress at the single-cell level,as well as inhibition of biofilm formation and quorum sensing at the population level.Certain PNPs have been harnessed as natural antimicrobial agents for the food preservation.The utilization of encapsulation technology proves to be an effective strategy in protecting PNPs,thereby ensuring good antimicrobial efficacy,enhanced dispersibility,and controlled release within food products.The utilization of nanoemulsions,nanoliposomes,edible packaging,electrospun nanofibers,and microcapsules formed by encapsulation has enriched the ways in which PNPs can be applied in food preservation.Although PNPs have great potential in food preservation,their widespread application in the food industry is currently constrained by factors such as production costs,safety concerns,and legal considerations.Chemical synthesis and biosynthesis pathways offer viable strategies for reducing the cost of producing PNPs,and ongoing efforts to assess safety and improve regulatory frameworks are likely to facilitate the broader adoption of PNPs in food preservation practices.This article provides an overview of the main types of PNPs with antimicrobial activity and their properties,focusing on their mechanisms of action.Additionally,it summarizes the use of PNPs in food preservation and discusses the characteristics and applications of different encapsulation technologies.Lastly,the paper briefly analyzes current limitations and proposes potential future trends for this field.
基金supported by the Beijing Science and Technology Planning Project of the Beijing Science and Technology Commission(Z241100009024047)the High-Level Public Health Technical Talent Training Plan(lingjunrencai-01-02).
文摘Respiratory infections are associated with high morbidity and mortality and are a major global health problem[1].Acute respiratory infections are caused by multiple respiratory pathogens,including viruses and bacteria.Viral-bacterial co-infections,which have become increasingly common and a global concern,can lead to substantial complications,causing higher morbidity and adverse prognosis[2].Previous studies have reported low positive detection rates of targeted pathogens related to acute respiratory infections,owing to the limited number of detected pathogens and variations in the sensitivity of diagnostic methods[3-4].Low positive detection rates may impede our understanding of respiratory pathogen characteristics and hamper the development of precise treatment and prevention strategies.
基金supported by grants from the National Key Research and Development Program of China(Nos.2023YFA0915200,2023YFA0915204)the Equipment Research and Development Projects of the Chinese Academy of Sciences(No.PTYQ2024YZ0010)+3 种基金the Science and Technology Commission of Shanghai Municipality Project(No.XTCX-KJ-2024-038)the Natural Science Foundation of Hebei Province of China(No.H2024206249)the Postdoctoral Fellowship Program of CPSF(No.GZC20232838)Science and Technology Commission of Shanghai Municipality(No.22S31901700).
文摘The implementation of multiple pathogen testing is essential for a rapid response to future outbreaks and for reducing disease transmission.This study introduces a 96-channel microfluidic chip,fabricated through a molding process,which enables the batch detection of pathogens.It explores the rapid lysis and elution processes of pathogens within the microfluidic chips to ensure that nucleic acid extraction,elution,and amplification are completed entirely within the chip.This chip can extract nucleic acids from samples in just 10 min,achieving an extraction efficiency comparable to that of traditional in-tube methods.An oil phase is pre-loaded into the chip to effectively prevent aerosol contamination.This approach allows for the simultaneous detection of 21 common respiratory pathogens,with a detection limit of 10 copies per reaction.Furthermore,applications involving clinical samples demonstrate significant practicality.Compared to many traditional in-tube pathogen detection methods and molecular biology technologies that utilize microfluidic chips,this detection chip not only enables simultaneous detection of multiple pathogens but also demonstrates high sensitivity.
基金supported by the Construction of High Quality and Efficient Mechanized Scientific and Technological Innovation Talent Team of Characteristic Coarse Cereals in Guizhou Province,China(No.BQW[2024]009)the Research and Integrated Application of Key Technologies of Green and High Yield in Characteristic Mountain Agriculture,China(No.[2023]07)the Guizhou Provincial Science and Technology Project of China(No.[2022]091)。
文摘Plant-parasitic nematodes(PPNs)(Meloidogyne sp.,Globodera sp.,and Pratylenchus sp.)and fungi are two of the most economically important groups of organisms affecting agricultural productivity worldwide.The interactions among PPNs,biocontrol fungi,and soil ecosystem can significantly impact plant health,disease management,and ecosystem functioning.We aimed to provide a comprehensive overview of the complex relationships between PPNs and biocontrol fungi,including pathogenic and biocontrol interactions.We summarized the molecular and ecological mechanisms underlying these interactions,highlighting the key players,signaling pathways,and environmental factors that influence the interactions.We also reviewed current knowledge on fungus-based biocontrol strategies against PPNs,including the development of novel management approaches.Furthermore,we explored the prospects of nematode-fungus interactions in agriculture,including the potential applications and technologies,precision agriculture,and integrated pest management approaches.This review highlights the need for further research on nematode-fungus interactions and their impact on plant infection and productivity,with an emphasis on the development of sustainable and effective strategies for managing PPNs and enhancing plant health in agricultural ecosystems.
基金supported by the Natural Science Foundation of Zhejiang Province of China,Nos.LZYQ25H270001(to LY),LY24H270007(to WJ)Zhejiang Province Traditional Chinese Medicine Science and Technology Plan Project,No.2023ZR011(to LY)+2 种基金China Postdoctoral Science Foundation,No.2023TQ0295(to LY)Postdoctoral Research Projects Merit-based Funding in Zhejiang Province(First-class funding),No.ZJ2023021(to LY)Xinmiao Talents Project of Zhejiang Province,No.2024R410A022(to YC).
文摘Neurodegenerative diseases are a class of disorders with the gradual loss of the central nervous system and peripheral nervous system.Neurodegenerative diseases manifest primarily as cognitive and behavioral disorders that adversely affect the lives of millions of people worldwide.Therefore,it is necessary to elucidate the mechanism of neurodegenerative diseases further and find effective new therapies.In recent years,increasing evidence has shown that the immune system plays a significant role in the pathophysiology of neurodegenerative diseases and regulates this process.The central and peripheral immune systems exert different roles in the disease progression.The development of neurodegenerative diseases is influenced by interactions between them.This review focuses on how the immune system,including microglia mediated nucleotide-binding oligomerization domain-like receptor protein 3 inflammation activation and T cell-mediated neuroinflammation,interactions with neurodegenerative diseases by modulating protein aggregation and blood-brain barrier permeability.Besides,we gave particular attention to glial cell-centered multicellular interactions and the inflammatory signaling pathway.Insight into the immune system’s functions and cellular interactions is essential for progressing disease research.In addition,the functions and mechanisms of these immune cells also suggest new ideas and targets for treatment.Therefore,this review summarizes some of the existing treatment strategies for amyloid-beta,tau,neuroinflammation,α-synuclein,associated microbiota,immune modulation,and neural injury repair.In addition,this review summarizes and compares animal models of different common neurodegenerative diseases and clinical research progress.In view of the current research status,new research directions and suggestions are proposed.
基金supported by grants from the National Natural Science Foundation of China(32172890 and 32002315)the National Key Research and Development Program of China(2022YFF0711004)+3 种基金the Natural Science Foundation of Heilongjiang Province,China(YQ2022C042)the State Key Laboratory of Veterinary Biotechnology Foundation of China(SKLVBF202208)the Postdoctoral Fellowship Program of CPSF,China(GZC20233062)the National Center of Technology Innovation for Pigs,China(NCTIP-XD/C09)。
文摘NADC34-like porcine reproductive and respiratory syndrome virus(PRRSV),which first appeared in China in 2017,is currently one of the main epidemic strains in China.In this study,we found that a new variant of NADC34-like PRRSV evolved,named the L1A variant.The phylogenetics,epidemic status,and pathogenicity of the LA variants were subsequently comprehensively evaluated.Based on the results of the ORF5 phylogenetic analysis,the L1A variants were classified as NADC34-like PPRSV.All the strains had the same discontinuous 131-aa deletion in the NSP2 region(similar to that in the NADC30).Recombination analysis revealed that the L1A variants were recombinant viruses that contained an NADC30-like PRRSV skeleton,a nonstructural protein-encoding gene region obtained in part from JXA1-like PRRSV and a ORF2-ORF6 gene region partly obtained from NADC34-like PRRSV and that exhibited similar recombination patterns.We successfully isolated the L1A variant TZJ2756 from PAMs and Marc-145 cells.In animal experiments,TZJ2756 exhibited moderate pathogenicity in piglets,causing obvious clinical symptoms,namely,persistent fever,significantly reduced body weight,interstitial edema and severe interstitial pneumonia in the lungs,and prolonged high-load viremia.L1A variants have been detected in at least 12 provinces in China and share many similar epidemiological characteristics with the American L1C variant.This research will enhance our understanding of the prevalence of L1A variants and furnish valuable data for the ongoing monitoring of NADC34-like PRRSV in China.
基金supported by the Ministry of Science and Technology of the People’s Republic of China(2022YFD1800400).
文摘Staphylococcus aureus(S.aureus)is the third most common pathogen causing 10.6%of bacterial foodborne illnesses in China in 2021[1].Heat-stable Staphylococcal Enterotoxins(SEs)produced by S.aureus are the main contributors to staphylococcal food poisoning(SFP),causing vomiting,diarrhea,abdominal pain,headache,muscle cramps,and other acute gastroenteritis symptoms.More than 25 SEs and staphylococcal enterotoxin-like toxins(SE/s)have been described and which together comprise a superfamily of pyrogenic toxin superantigens(SAgs)[2].
基金supported by the National Natural Science Foundational of China,Nos.U24A20692(to CJZ),82371355(to CJZ),and 82101414(to MH)National NaturalScience Foundational of China for Excellent Young Scholars,No.82022019(to CJZ)+5 种基金Sichuan Special Fund for Distinguished Young Scholars,No.24NSFJQ0052(to CJZ)The Innovationand Entrepreneurial Team of Sichuan Tianfu Emei Program,No.CZ2024018(to CJZ)Funding for Distinguished Young Scholars of Sichuan Provincial People’sHospital,No.30420230005Funding for Distinguished Young Scholars of University of Electronic Science and Technology of China,No.A1098531023601381(toCJZ)Sichuan Science and Technology Support Project,No.2023YFS0212(to BH)Project of Sichuan Provincial Health Commission,No.19PJ265(to LD).
文摘Multiple sclerosis is a severe autoimmune disorder that is mainly mediated by pathogenic cluster of CD4^(+)T cell subsets.Despite advancements in the management of multiple sclerosis,there is a critical need for more effective and safer treatments.In the present study,we administered Lycium barbarum glycopeptide to a mouse model of experimental autoimmune encephalomyelitis-an animal model of multiple sclerosis-and evaluated its effects on pathogenic CD4^(+)T cell activation both in vivo and in vitro.Lycium barbarum glycopeptide significantly mitigated the clinical severity of experimental autoimmune encephalomyelitis,as demonstrated by reduced demyelination and neuroinflammation.Moreover,Lycium barbarum glycopeptide treatment decreased the infiltration of peripheral leukocytes into the central nervous system and suppressed pro-inflammatory cytokine expression.Lycium barbarum glycopeptide also modulated pathogenic CD4^(+)T cell activation by inhibiting T helper 1/T helper 17 cell differentiation while promoting regulatory T cell expansion.Notably,no side effects were observed,suggesting the long-term safety and tolerability of Lycium barbarum glycopeptide.Furthermore,RNA sequencing data indicated that Lycium barbarum glycopeptide inhibits activator protein-1,an essential regulator of T cell activation and differentiation.This finding was supported by the reversal of T helper/T helper 17 cell response suppression upon AP-1 blockade.Collectively,these results highlight the potential of Lycium barbarum glycopeptide as an innovative therapeutic agent for CD4^(+)T cell-associated autoimmune or inflammatory diseases,such as multiple sclerosis.
基金Major National Science and Technology Projects(Grant No.2013ZX10004605,2013ZX10004605001004)
文摘The pathogens and opinion for antibiotic treatment in adult patients with 1-14 fecal white blood cells per high power field （WBC/HPF） of acute non-bloody diarrhea remain obscure. The study attempts to clarify it. Stool specimens of adult patients with acute non-bloody diarrhea and stool examination showing 1-14 fecal WBC/HPF were collected for bacterial culture and viral detection. Patients included in this study were 196 cases with mean age of （37.9±17.4） years and 42.3% was women. The bacterial and viral detection rates were 63 （32.1%） and 21 （10.7%）, respectively. Of the isolated pathogens, campylobacteria was present in 14 （22.0%） samples and was the most common bacteria and calicivirus was found in 10 （47.6%） samples and was the most common virus. Based on single pathogens, 46 cases were caused by invasive pathogens, 26 cases were caused by non-invasive pathogens. The body temperature was significantly higher in feverish patients caused by invasive pathogens than those caused by non-invasive pathogens （（38.44-0.7） ℃ vs （37.74-0.4） ℃, P = 0.002）. The probability of diarrhea caused by invasive pathogens was higher in patients with T〉38.4℃ than those with T_〈38.4℃ （RR = 1.5）. When T〉38.4℃ is used as the threshold for antibiotic treatment, the misuse rate of antibiotics would decrease from 26.9% to 3.8% （P = 0.021）. So T〉38.4 ℃ may be used as a possible reference value for antibiotic treatment in adult patients with 1-14 fecal WBC/HPF of acute non-bloody diarrhea.
基金Supported by Science and Technology Plan Project of Fujian Province(2013Y0063)Xiamen South Ocean Research Centre Project(13GZP002NF08)~~
文摘[Objective] The aim of this study was to purify an antimicrobial protein from a biocontrol bacterium strain K2-1 and analyze its antimicrobial activity in vitro against some typical aquatic pathogens. [Method] The antimicrobial protein was ob- tained by using ammonium sulfate precipitation and Sephadex chromatography combined with hot water bath. The antimicrobial assay was conducted by means of agar diffusion technique, using Vibrio alginolyticus, Aeromonas hydrophila, Aeromonas. Sobria, Pseudomonas fluorescens, Vibrio Parahaemolyticus, Vibrio har- veyi and Vibrio anguillarum as test bacteria. [Result] Antimicrobial protein APK2 can be derived from fermentation broth of strain K2-1 and purified to the chromatogra- phy pure level by the methods provided, the final yield of the antimicrobial compo- nent is approximately 0.08%. This antimicrobial protein had a strong antimicrobial activity against the growth of most those bacteria. [Conclusion] The results show that APK2 could be a potential alternative to replace chemical antimicrobial agent in the control and prevention of aquatic diseases.
基金supported in part by the Universidad de los Andes Faculty of Sciencesby basic sciences project P13.700022.007 from the University of los Andes Office of Research+1 种基金by COLCIENCIAS grant # 120-4521-28532Colciencias (Programa de Apoyo a Doctorados Nacionales) for the financial support of the Ph.D. studies of M.F.G. and H.Y.N.-O
文摘The importance of pyrimidines lies in the fact that they are structural components of a broad spectrum of key molecules that participate in diverse cellular functions, such as synthesis of DNA, RNA, lipids, and carbohydrates. Pyrimidine metabolism encompasses all enzymes involved in the synthesis, degradation, salvage, interconversion and transport of these molecules. In this review, we summarize recent publications that document how pyrimidine metabolism changes under a variety of conditions, including, when possible, those studies based on techniques of genomics, transcriptomics, proteomics, and metabolomics. First, we briefly look at the dynamics of pyrimidine metabolism during nonpathogenic cellular events. We then focus on changes that pathogen infections cause in the pyrimidine metabolism of their host. Next, we discuss the effects of antimetabolites and inhibitors, and finally we consider the consequences of genetic ma- nipulations, such as knock-downs, knock-outs, and knock-ins, of pyrimidine enzymes on pyrimidine metabolism in the cell.
基金supported by the National Natural Science Foundation of China(No.51290281)the project of Chinese Academy of Sciences(No.QYZDY-SSW-DQC004)the Federal Department of Chinese Water Control and Treatment(Nos.2017ZX07108,2017ZX07501002)
文摘The effects of O3/Cl2 disinfection on corrosion and the growth of opportunistic pathogens in drinking water distribution systems were studied using annular reactors （ARs）. The corrosion process and most probable number （MPN） analysis indicated that the higher content of iron-oxidizing bacteria and iron-reducing bacteria in biofilms of the AR treated with O3/Cl2 induced higher Fe304 formation in corrosion scales. These corrosion scales became more stable than the ones that formed in the AR treated with Cl2 alone. O3/Cl2 disinfection inhibited corrosion and iron release efficiently by changing the content of corrosion-related bacteria. Moreover, ozone disinfection inactivated or damaged the opportunistic pathogens due to its strong oxidizing properties. The damaged bacteria resulting from initial ozone treatment were inactivated by the subsequent chlorine disinfection. Compared with the AR treated with Cl2 alone, the opportunistic pathogens M. auium and L. pneumophila were not detectable in effluents of the AR treated with O3/Cl2, and decreased to （4.60 ± 0.14） and （3.09 ± 0.12） loglo （gene copies/g corrosion scales） in biofilms, respectively. The amoeba counts were also lower in the AR treated with O3/Cl2. Therefore, O3/Cl2 disinfection can effectively control opportunistic pathogens in effluents and biofilms of an AR used as a model for a drinking water distribution system.
基金supported by the National Natural Science Foundation of China(No.51138006)the National Key Research on Water Environment Pollution Control in China(No.2012ZX07301-001)
文摘The emergence and prevalence of antibiotic resistance genes(ARGs) and pathogens in the environment are serious global health concern. However, information about the occurrence of ARGs and pathogens in recreational water is still limited. Accordingly, we investigated the occurrence of six ARGs and human pathogens in three recreational lakes, and the correlations between ARGs and one mobile genetic element(intI1) were analyzed. The quantitative PCR results showed that the concentration of ARGs ranged from 4.58 × 10~0 to 5.0 × 10~5 copies/mL in water and from 5.78 × 10~3 to 5.89 × 10~8 copies/g dry weight(dw)in sediment. Sul1 exhibited the highest level among the five quantifiable ARGs. The concentrations of sul1, bla_(-TEM), and tetX exhibited significant positive correlations with intI1(p < 0.05), indicating that intI1 may be involved in their proliferation. The detection frequencies of ARGs ranged from 75%–10~0%, indicating the prevalence of these risks in this region. The concentration of Escherichia coli, Aeromonas spp., Mycobacterium avium,Pseudomonas aeruginosa, and Salmonella enterica ranged from 10~3 to 10~5 copies/10~0 mL in water and 10~4–10~6 copies/g dw in sediment. In total, 25% of the samples harbored all pathogen genes, indicating the prevalence of these pathogens in recreational lakes.Furthermore, the next-generation sequencing results showed that 68 genera of pathogens were present, among which Aeromonas, Mycobacterium, and Pseudomonas were the dominant ones in this region, posing a considerable potential health risk to public health. Overall, the widespread distribution of ARGs and pathogens underscores the need to better monitor and mitigate their propagation in recreational lakes and the associated risks to human health.
基金supported by the National Basic Research Development Program of China(Grant No. 2009CB118401)the National High-tech Research and Development Program of China(Grant Nos.2012AA10A305 and 2012AA 101104)
文摘Plant pathogens have evolved numerous strategies to obtain nutritive materials from their host, and plants in turn have evolved the preformed physical and chemical barriers as well as sophisticated two-tiered immune system to combat pathogen attacks. Genetically, plant resistance to pathogens can be divided into qualitative and quantitative disease resistance, conditioned by major gene（s） and multiple genes with minor effects, respectively. Qualitative disease resistance has been mostly detected in plant defense against biotrophic pathogens, whereas quantitative disease resistance is involved in defense response to all plant pathogens, from biotrophs, hemibiotrophs to necrotrophs. Plant resistance is achieved through interception of pathogen-derived effectors and elicitation of defense response. In recent years, great progress has been made related to the molecular basis underlying host--pathogen interactions. In this review, we would like to provide an update on genetic and molecular aspects of plant resistance to pathogens.
