Traditional Chinese medicine has unique advantages in preventing and treating COVID-19,and Fuzheng Jiedu decoction(FZJDD)was reported to be effective against COVID-19 in clinical trials.To investigate the potential me...Traditional Chinese medicine has unique advantages in preventing and treating COVID-19,and Fuzheng Jiedu decoction(FZJDD)was reported to be effective against COVID-19 in clinical trials.To investigate the potential mechanisms and material basis of FZJDD against SARS-CoV-2,we performed SARS-CoV-2 target protein inhibition analyses and a metabolite full spectrum analysis of FZJDD.Interestingly,FZJDD was found to block the binding of SARS-CoV-2 Spike protein with the receptor ACE2 and inhibit the activity of SARS-CoV-23CLpro.Moreover,FZJDD can regulate the TNF and the MAPK signaling pathway to inhibit the inflammatory response and alleviate the“cytokine storm”.A total of 298 compounds were identified in FZJDD,among them,caffeic acid and octyl gallate were found to be the potential therapeutic agents of FZJDD.Importantly,FZJDD can broadly inhibit coronavirus infection,including SADS-CoV and porcine epidemic diarrhea virus(PEDV)live viruses,SARS-CoV,MERS-CoV,and SARS-CoV-2 mutant pseudotyped viruses,which might be ascribed to the broad-spectrum anti-coronavirus activity of caffeic acid and octyl gallate.In conclusion,this study reveals the mechanisms and material basis of FZJDD against SARS-CoV-2 and identifies the broadspectrum anti-coronavirus activity of FZJDD for the first time.Our data provide empirical evidence for the development and application of FZJDD.展开更多
Displacement damage induced by high-energy protons in the space radiation environment presents a serious risk to the reliability of spacecraft materials and onboard electronics.Nevertheless,studies on displacement dam...Displacement damage induced by high-energy protons in the space radiation environment presents a serious risk to the reliability of spacecraft materials and onboard electronics.Nevertheless,studies on displacement damage induced by spacebased broad-spectrum protons are still limited.In this paper,the nonionizing energy loss(NIEL)of space broad-spectrum protons at different orbital altitudes in semiconductor materials is investigated using Geant4 Monte Carlo simulations.We find that the NIEL of silicon(Si)and gallium arsenide(GaAs)first increases and then decreases with orbital altitude,and that shielding effects can result in either the saturation or continuous increase of NIEL,depending on the shielding layer thickness.A fast NIEL calculation method for arbitrary broad spectra is proposed based on statistical probability principles and the effective proton proportion.Meanwhile,a more uniform spatial distribution of mean damage energy per source particle(T_(dam))deposition from broad-spectrum protons can be achieved by increasing the shielding layer thickness and lowering the orbital altitude.Notably,the relative contribution of displacement damage caused by nuclear reactions decreases with increasing orbital altitude and shielding layer thickness.The results provide a quantitative reference for space displacement damage in semiconductor materials.展开更多
[Objective] It is to clone broad-spectrum anti-disease gene NPR1 and to construct its protein expression vector.[Method] First to extract total RNA of Arabidopsis thaliana and design relevant primers,and then the meth...[Objective] It is to clone broad-spectrum anti-disease gene NPR1 and to construct its protein expression vector.[Method] First to extract total RNA of Arabidopsis thaliana and design relevant primers,and then the method of reverse transcription PCR was adopted to clone.With the method of enzyme digestion and ligation,this gene will be directed into protein expression vector.[Result] After relevant testing,NPR1 was inserted into vector pMXB10 to obtain pMXB10-NPR1 protein expression vector.[Conclusion] Protein expression vector including NPR1 was successfully constructed.展开更多
Pathogen infection is the main cause of human morbidity and death.Traditional antibiotics usually sterilize bacteria in chemical ways,which tends to develop serious antibiotic resistance.Cationic polymers exhibit good...Pathogen infection is the main cause of human morbidity and death.Traditional antibiotics usually sterilize bacteria in chemical ways,which tends to develop serious antibiotic resistance.Cationic polymers exhibit good bacterial inhibition with less resistance,but often face severe cytotoxicity toward normal cells.The optimization of polymeric antimicrobials for enhanced bactericidal capacity and improved biocompatibility is quite meaningful.In addition,photodynamic therapy(PDT)is a therapeutic modality with less susceptibility to develop resistance.Herein,a typical commercial polymeric antimicrobial,polyhexamethylene guanidine(PHMG)was selected for current proof-of-concept optimization due to its excellent bactericidal capacity but moderate biocompatibility.Eosin-Y(EoS)was copolymerized to afford EoS-labeled polymer conjugates,poly(2-(dimethylamino)ethyl methacrylate-co-eosin),P(DMAEMA-co-EoS),which was conjugated with PHMG to afford a novel polymeric antimicrobial,P(DMAEMA-co-EoS)-b-PHMG-b-P(DMAEMA-co-EoS),noted as PEoS-PHMG.It could efficiently kill broad-spectrum bacteria by physical damage and photodynamic therapy.Compared with PHMG,the bacterial inhibition of PEoS-PHMG was potentiated after the functionalization.Furthermore,PEoS-PHMG exhibited low cytotoxicity and minimal hemolysis,which was demonstrated by cell viability assays toward LO2 cells and RAW 264.7 cells as well as hemolytic assays against red blood cells.These results confirmed that the resultant PEoS-PHMG could act as promising alternative antibacterial materials with excellent broad-spectrum bacterial inhibition and favorable biocompatibility.展开更多
[ Objectives] Rice materials with broad-spectrum resistance against several pathogenic strains of Xanthomans oryzae pv. Oryzicola （Xooc） at multiple growth stages were screened, in order to provide reliable resistan...[ Objectives] Rice materials with broad-spectrum resistance against several pathogenic strains of Xanthomans oryzae pv. Oryzicola （Xooc） at multiple growth stages were screened, in order to provide reliable resistance sources for variety breeding against rice bacterial leaf streak. [ Methods] A total of 1 100 rice lines with rich genetic background were offered as selective objects, and highly susceptible cultivar Jingang 30 was used as the control. Inoculation was carried out with five strong pathogenic strains of Xooc through acupuncture method at various growth stages for resistance identification. [ Results] Fourteen disease-resistant materials were obtained through preliminary screening, accounting for 1.27% of the total materials. Nine materials moderately resistant to bacterial leaf streak were obtained via secondary screening, accounting for 0.82% of the total materials. Besides, three of them （ RL6, RL9 and RLL4） were resistant to a number of pathogenic strains of Xooc at three growth stages. In particular, RL16 presented broad-spectrum resistance to multi-strains with high resistance levels. Six of them （ RI2, RIA, RIS, RL8, RL11 and RL12） were resistant to single strain at single growth stage. [ Conclusions] The obtained three materials have broad-spectrum resistance to bacterial leaf streak at multiple growth stages, which can be served as an important source to cultivate disease-resistant rice varieties. RL6 maintains high broad-spectrum resistance at all growth stages, which can be used as a prior resistance source for rice variety breeding. Six materials obtained with resistance against bacterial leaf streak at particular growth stages can be used as candidate resistance sources.展开更多
Coronaviruses exist widely in nature,can cause cross-species transmission,and pose serious threats to human and animal health.Over the past 20 years,coronaviruses have led to three major epidemics that have caused glo...Coronaviruses exist widely in nature,can cause cross-species transmission,and pose serious threats to human and animal health.Over the past 20 years,coronaviruses have led to three major epidemics that have caused global panic,including severe acute respiratory syndrome,Middle East respiratory syndrome,and coronavirus disease-19.At present,coronavirus disease 19 not only spreads rapidly,but also mutates easily to escape host immune response,becoming more pathogenic.At present,there are no effective specific therapeutic drugs or vaccines.Drugs targeting severe acute respiratory syndrome coronavirus 2 and the host cell defense system that have been developed based on the structure and replication cycle of coronaviruses have a certain broad-spectrum antiviral effect;however,their efficacy still needs to be demonstrated in further clinical trials.Traditional Chinese medicine has an indispensable role in the ongoing response to coronavirus disease-19.Anti-virus treatment with traditional Chinese medicine has advantages such as broad-spectrum application,low toxicity and side effects,low susceptibility to drug resistance,and overall comprehensive regulation.Therefore,researches on effective components and mechanisms of action of the anti-viral effects of traditional Chinese medicine have increasingly gained attention.The present paper examines coronaviruses,specifically summarizing the genomes,replication mechanisms,and mutant strains.Afterward,the therapeutic effects and mechanisms of action of modern broad-spectrum anti-coronavirus drugs and traditional Chinese medicine are summarized.By considering the virus and the targets in the host comprehensively,in addition to the beneficial multi-target and multi-path antiviral effects of traditional Chinese medicines,this paper could guide the development of treatment strategies for broad-spectrum anti-coronavirus traditional Chinese medicines,and could facilitate the modernization and globalization of traditional Chinese medicine.展开更多
Hepatic encephalopathy(HE)is a formidable complication in patients with decompensated cirrhosis,often necessitating the administration of rifaximin(RFX)for effective management.RFX,is a gut-restricted,poorly-absorbabl...Hepatic encephalopathy(HE)is a formidable complication in patients with decompensated cirrhosis,often necessitating the administration of rifaximin(RFX)for effective management.RFX,is a gut-restricted,poorly-absorbable oral rifamycin derived antibiotic that can be used in addition to lactulose for the secondary prophylaxis of HE.It has shown notable reductions in infection,hospital readmission,duration of hospital stay,and mortality.However,limited data exist about the concurrent use of RFX with broad-spectrum antibiotics,because the patients are typically excluded from studies assessing RFX efficacy in HE.A pharmacist-driven quasi-experimental pilot study was done to address this gap.They argue against the necessity of RFX in HE during broad-spectrum antibiotic treatment,particularly in critically ill patients in intensive care unit(ICU).The potential for safe RFX discontinuation without adverse effects is clearly illuminated and valuable insight into the optimization of therapeutic strategies is offered.The findings also indicate that RFX discontinuation during broadspectrum antibiotic therapy was not associated with higher rates of delirium or coma,and this result remained robust after adjustment in multivariate analysis.Furthermore,rates of other secondary clinical and safety outcomes,including ICU mortality and 48-hour changes in vasopressor requirements,were comparable.However,since the activity of RFX is mainly confined to the modulation of gut microbiota,its potential utility in patients undergoing extensive systemic antibiotic therapy is debatable,given the overlapping antibiotic activity.Further,this suggests that the action of RFX on HE is class-specific(related to its activity on gut microbiota),rather than drug-specific.A recent double-blind randomized controlled(ARiE)trial provided further evidence-based support for RFX withdrawal in critically ill cirrhotic ICU patients receiving broad-spectrum antibiotics.Both studies prompt further discussion about optimal therapeutic strategy for patients facing the dual challenge of HE and systemic infections.Despite these compelling results,both studies have limitations.A prospective,multi-center evaluation of a larger sample,with placebo control,and comprehensive neurologic evaluation of HE is warranted.It should include an exploration of longer-term outcome and the impact of this protocol in non-critically ill liver disease patients.展开更多
An amphiphilic AIE photosensitizer has been successfully developed,which allows for easily inserting into the bacterial membranes.Binding experiments with phospholipid preliminary demonstrates its membrane specificity...An amphiphilic AIE photosensitizer has been successfully developed,which allows for easily inserting into the bacterial membranes.Binding experiments with phospholipid preliminary demonstrates its membrane specificity.As expected,it is proved to possess a broad-spectrum bacterial staining performance and photodynamic antibacterial activity toward S.aureus and E.coli.展开更多
The emergence and re-emergence of RNA virus outbreaks highlight the urgent need for the development of broadspectrum antivirals.Polyamines are positively-charged small molecules required for the infectivity of a wide ...The emergence and re-emergence of RNA virus outbreaks highlight the urgent need for the development of broadspectrum antivirals.Polyamines are positively-charged small molecules required for the infectivity of a wide range of RNA viruses,therefore may become good antiviral targets.Cucurbit[7]uril(CB[7]),a synthetic macrocyclic molecule,which can bind with amine-based organic compounds with high affinity,has been shown to regulate bioactive molecules through competitive binding.In this study,we tested the antiviral activity of CB[7]against diverse RNA viruses,including a panel of enteroviruses(i.e.human enterovirus A71,coxsackievirus A16,coxsackievirus B3,and echovirus 11),some flaviviruses(i.e.dengue virus and Zika virus),and an alphavirus representative Semliki forest virus.CB[7]can inhibit virus replications in a variety of cell lines,and its mechanism of action is through the competitive binding with polyamines.Our findings not only for the first time provide evidence that CB[7]can be a promising broad-spectrum antiviral agent,but more importantly,offer a novel therapeutic strategy to fight against RNA viruses by supramolecular sequestration of polyamines.展开更多
Purpose: To investigate 1) the development in the incidence of ESBL-producing bacteria in hospitals and primary health care, 2) the contribution of primary health care to the incidence of ESBL-producing bacteria, and ...Purpose: To investigate 1) the development in the incidence of ESBL-producing bacteria in hospitals and primary health care, 2) the contribution of primary health care to the incidence of ESBL-producing bacteria, and 3) the development in resistance patterns for all Escherichia coli and Klebsiella pneumoniae isolates in relation to antimicrobial consumption in hospitals and primary health care. Methods: ESBL-data were retrospectively collected from bacterial isolates from all specimens received at the Department of Clinical Microbiology from 2003 to 2011 together with the corresponding patient data. ESBL-production was detected in isolates from 1067 of 59,373 patients (1.8%) with an E. coli infection and in 263 of 8660 patients (3.0%) with a K. pneumoniae infection. Results: From 2003 to 2009, an increase in patients with an ESBL-producing isolate occurred in both hospitals and primary health care at the same time as an increased consumption of broad-spectrum antimicrobial agents was seen. Interventions to reduce prescription of cephalosporins and ciprofloxacin at the hospitals from 2010 resulted in a remarkable decrease in patients with ESBL-producing K. pneumoniae whereas a continuing increase was seen in patients with ESBL-producing E. coli both at hospitals and in primary health care. The proportion of patients with community-acquired ESBL-producing E. coli was stable with an increase of only 1.4% from 2007 to 2011. Conclusions: Reduction in prescription of broad-spectrum antimicrobial agents at the hospital level had an important impact on the incidence of ESBL-producing K. pneumoniae, but not on ESBL-producing E. coli.展开更多
Yield loss caused by crop diseases seriously restricts global food security.Breeding disease-resistant varieties with resistance(R)genes is acknowledged as the most economical and effective way to control diseases.The...Yield loss caused by crop diseases seriously restricts global food security.Breeding disease-resistant varieties with resistance(R)genes is acknowledged as the most economical and effective way to control diseases.Therefore,exploring broad-spectrum resistance(BSR)genes to pathogens and clarifying the underlying mechanism are the basis for effective utilization of BSR resources and finding new approaches for disease control.In the past 20 years,significant progress has also been made in plant immune mechanism and remarkable achievements have been made in researches on broad-spectrum disease resistance of major grain crops,and the potential molecular mechanisms of some BSR have been revealed.Here,the advances of broad-spectrum disease resistance in rice(including the representative cloned BSR genes and their molecular mechanisms)were reviewed.In addition,the problems,opportunities and challenges encountered by BSR were analyzed,and the development of BSR research and its application in rice production were prospected.展开更多
Hepatic encephalopathy(HE)is one of the main complications of cirrhosis,characterized by a wide spectrum of neuropsychiatric alterations that lead to an increase in mortality,morbidity and recurrent hospitalizations.D...Hepatic encephalopathy(HE)is one of the main complications of cirrhosis,characterized by a wide spectrum of neuropsychiatric alterations that lead to an increase in mortality,morbidity and recurrent hospitalizations.Due to the central role in HE pathogenesis of ammonia and other neurotoxins primarily produced by the gut microbiota,the main therapeutic approaches for the treatment of HE are based on the modulation of the gut microbiota.Rifaximin is a non-absorbable broad-spectrum antibiotic,that is effective against ammonia-producing grampositive,gram-negative,and anaerobic species,approved for the treatment of HE in secondary prophylaxis.The chronic administration of rifaximin in this setting is associated with a lower risk of HE recurrence and mortality,while the role of rifaximin for the treatment of an overt-HE episode in inpatients is still unclear.Limited data exist about the coadministration of rifaximin and broad-spectrum antibiotics commonly used to treat concomitant infections,as patients receiving or recently treated with antibiotics were frequently excluded from clinical trials.In this editorial we comment on the article by Ward et al published in the recent issue of the World Journal of Hepatology.It is a single center,retrospective,quasiexperimental,pharmacist-driven protocol,with the aim to evaluate the feasibility and safety of rifaximin discontinuation in critically ill patients with HE and chronic liver disease receiving broad-spectrum antibiotic therapies in intensive care units.The study revealed no differences between the protocol and control group in terms of primary outcome(days alive and free of delirium and coma to day 14)and secondary outcomes which include:Intensive care mortality,intensive care length of stay,intravenous vasopressor requirement changes and adverse effects rate.Therefore,rifaximin discontinuation during broad-spectrum antibiotic therapy does not appear to negatively impact the clinical status of critically ill liver patients,with a similar safety profile and significant cost savings,as compared to the coadministration of rifaximin and broad-spectrum antibiotics.In agreement with Ward et al,a recently published double-blind,randomized controlled trial provided additional evidence to support the feasibility of withholding rifaximin during broad-spectrum antibiotic therapy in critically ill cirrhotic patients.However,given the limitations of these studies,further multicentric and prospective clinical trials,enrolling a larger sample of non-critically ill patients,are needed to better establish the role of rifaximin in this setting.展开更多
BACKGROUND Pediatric abdominal infection is a common but serious disease that requires timely and effective treatment.In surgical treatment,accurate diagnosis and rational application of antibiotics are the keys to im...BACKGROUND Pediatric abdominal infection is a common but serious disease that requires timely and effective treatment.In surgical treatment,accurate diagnosis and rational application of antibiotics are the keys to improving treatment effects.AIM To investigate the effect of broad-spectrum bacterial detection on postoperative antibiotic therapy.METHODS A total of 100 children with abdominal infection who received surgical treatment in our hospital from September 2020 to July 2021 were grouped.The observation group collected blood samples upon admission and sent them for broad-spectrum bacterial infection nucleic acid testing,and collected pus or exudate during the operation for bacterial culture and drug sensitivity testing;the control group only sent bacterial culture and drug sensitivity testing during the operation.RESULTS White blood cell count,C-reactive protein,procalcitonin,3 days after surgery,showed better postoperative index than the control group(P<0.05).The hospital stay in the observation group was significantly shorter than that in the control group.The hospitalization cost in the observation group was significantly lower than that in the control group,and the difference between the two groups was statistically significant(P<0.05).CONCLUSION Early detection of broad-spectrum bacterial infection nucleic acids in pediatric abdominal infections can help identify pathogens sooner and guide the appropriate use of antibiotics,improving treatment outcomes and reducing medical costs to some extent.展开更多
Chloasma, or melasma, is a commonly acquired pigmentary disorder among Asian women. It may be considered as a physiological change during pregnancy. The incidence in Asian women is higher than that in other ethnic gro...Chloasma, or melasma, is a commonly acquired pigmentary disorder among Asian women. It may be considered as a physiological change during pregnancy. The incidence in Asian women is higher than that in other ethnic groups but further epidemiologic data are needed. There are very few studies related to the benefits of sunscreens to prevent this dermatosis. The aim of this study was to assess the effectiveness of a broad-spectrum sunscreen in the prevention of melasma in Korean pregnant women. We tested the effectiveness and tolerance of a sunscreen product (SPF 50+, UVA-PF 30) during a 12-month clinical trial including 220 Korean parturients with skin type III and IV. 217 women completed the study. Only 3 (1%) of the study population developed melasma, which was mild (MASI grade between 1.2 and 2.7). In addition, the clinical effectiveness of the evaluated sunscreen was judged “good to excellent” by the majority of study participants and by the research dermatologists. The “excellent” tolerance of the sunscreen under evaluation was confirmed “good” to “excellent” in 95% and 97% of cases. This study clearly demonstrates that this broad-spectrum sunscreen is well tolerated and effective in the prevention of melasma in Korean pregnant women. Although treatment remains elusive, prevention is possible.展开更多
Iminosugars,a class of polyhydroxylated cyclic alkaloids with intriguing properties,hold promising therapeutic potentials against a broad spectrum of enveloped viruses,including DENV,HCV,HIV,and influenza viruses.Mech...Iminosugars,a class of polyhydroxylated cyclic alkaloids with intriguing properties,hold promising therapeutic potentials against a broad spectrum of enveloped viruses,including DENV,HCV,HIV,and influenza viruses.Mechanistically,iminosugars act as the competitive inhibitors of host endoplasmic reticularα-glucosidases I and II to disrupt the proper folding of viral nascent glycoproteins,which thereby exerts antiviral effects.Remarkably,the glycoproteins of many enveloped viruses are significantly more dependent on the calnexin pathway of the protein folding than most host glycoproteins.Therefore,extensive interests and efforts have been devoted to exploit iminosugars as broad-spectrum antiviral agents.This review provides the summary and insights into the recent advancements in the development of novel iminosugars as effective and selective antiviral agents against a variety of enveloped viruses,as well as the understandings of their antiviral mechanisms.展开更多
Strains of the Enterobacteriaceae family producing ESBL and AmpC broad-spectrum beta-lactamases that may survive in the hospital setting potentially cause infection in hospitalized patients due to contaminated objects...Strains of the Enterobacteriaceae family producing ESBL and AmpC broad-spectrum beta-lactamases that may survive in the hospital setting potentially cause infection in hospitalized patients due to contaminated objects or health care workers’ hands. Over a period of two months (November-December 2010), a single epidemiological study of microbial contamination of air, surfaces and health care workers (swabs from both nostrils and the right hand without a glove) was carried out at two intensive care units of the University Hospital Olomouc, Czech Republic. The bacteria were identified using standard microbiological methods. Phenotypic detection of ESBL and AmpC enzymes and basic genetic analysis of ESBL- and AmpC-positive isolates was performed. The same approach was used to identify and analyze bacteria isolated from clinical samples of patients hospitalized at the above departments over the study period. From a total of 140 environmental samples collected over the study period, 21 isolates of the Enterobacteriaceae family were identified, with ESBL and AmpC production being detected in 4 and 7 isolates, respectively. Among patients’ clinical samples, 10 ESBL- and 6 AmpC-positive isolates were detected. No similarity was found between environmental isolates and strains isolated from patients.展开更多
A bacterial strain WY047 was isolated from fermented grains and the bacterium was identified as Bacillus amyloliquefaciens, based on morphological, biochemical, and physiological tests, and analysis of 16S rRNA and gy...A bacterial strain WY047 was isolated from fermented grains and the bacterium was identified as Bacillus amyloliquefaciens, based on morphological, biochemical, and physiological tests, and analysis of 16S rRNA and gyr A sequences. The culture supernatant of WY047 demonstrated inhibition ofa wide spectrum ofbacteria(Gram positive and Gram negative) and fungi. Nine pairs ofprimers were designed and six genes( bmyD, fenA, hag, ituA, mrsA, and tasA) ofantimicrobial substances were detected by PCR, one ofwhich was isolated by 80% ammonium sulfate precipitation, D201 resin anion-exchange chromatography, and Sephadex G-75 filtration column. The purified peptide was estimated to be 35,207 Da and identified as flagellin by MALDI-TOF mass spectrometry. Another four antimicrobial substances were extracted with methanol and identified as iturin A, fengycin, bacillomycin D, and mersacidin through the liquid chromatography–mass spectrometry(LC–MS) method. The sixth possible peptide encoded by tas A could not be isolated in this study; however, the broader spectrum suggested huge application prospects.展开更多
A recent study led by Yi-Wei Chang1,published in Science,integrates cryo-electron single-particle analysis(SPA)and cryo-electron tomography(cryo-ET)to elucidate the near-atomic architecture of the influenza virus ribo...A recent study led by Yi-Wei Chang1,published in Science,integrates cryo-electron single-particle analysis(SPA)and cryo-electron tomography(cryo-ET)to elucidate the near-atomic architecture of the influenza virus ribonucleoprotein(RNP)complex.The study reveals that the RNP adopts a right-handed,antiparallel double-helical configuration,in which the viral RNA is translocated via a polymerase-driven strand sliding mechanism.Dynamic tail loop interactions between adjacent nucleoprotein(NP)subunits impart structural flexibility to the RNP,enabling conformational dynamics essential for processive RNA synthesis.These findings define a structural basis for strand sliding,and guided by this insight,the authors identify novel small molecules that disrupt NP–NP interactions by targeting a conserved tail loop interface,laying a foundation for broad-spectrum influenza antivirals.展开更多
The operational efficiency of membrane electrode assemblies in direct liquid fuel cells is critically dependent on the fuel purity in the anode compartment.To address the inherent challenge of fuel mixing problem in a...The operational efficiency of membrane electrode assemblies in direct liquid fuel cells is critically dependent on the fuel purity in the anode compartment.To address the inherent challenge of fuel mixing problem in alcohol systems,we propose a rational catalyst design strategy focusing on morphological and compositional optimization.Sodium borohydride-derived PtCuMo alloy aerogels(AA)exhibit abundant grain boundary defects,while solvothermally prepared nanowire arrays(NA)maintain excellent single-crystalline characteristics.Density functional theory calculations demonstrate that engineered grain boundaries can effectively broaden the adsorption energy window for key reaction intermediates,enabling superior adaptability to diverse catalytic pathways.By precisely controlling Cu content,we identified Pt_(3)Cu_(3)Mo_(0.5)AA as the optimal catalyst configuration,demonstrating 150% enhancement in methanol oxidation reaction activity compared to Pt_(3)Cu_(6)Mo_(0.5)NA(1.5 vs.0.6 A·mg_(Pt)^(-1))and 17% improvement in ethanol oxidation reaction performance versus Pt_(3)Cu_(1)Mo_(0.5)NA(0.82 vs.0.70 A·mg_(Pt)^(-1)).Practical application testing using gas diffusion electrodes(anode loading:0.85 mg_(Pt)·cm^(-2))achieved a mass-specific power density of 14.14 W·g_(Pt)^(-1)in 1:1 methanol/ethanol blends,representing a 3.5-fold improvement over commercial Pt/C benchmarks.This work establishes a fundamental framework for developing highperformance,broad-spectrum electrocatalysts in advanced fuel cell systems.展开更多
Plant diseases,caused by a wide range of pathogens,severely reduce crop yield and quality,posing a significant threat to global food security.Developing broad-spectrum resistance(BSR)in crops is a key strategy for con...Plant diseases,caused by a wide range of pathogens,severely reduce crop yield and quality,posing a significant threat to global food security.Developing broad-spectrum resistance(BSR)in crops is a key strategy for controlling crop diseases and ensuring sustainable crop production.Cloning disease-resistance(R)genes and understanding their underlying molecular mechanisms provide new genetic resources and strategies for crop breeding.Novel genetic engineering and genome editing tools have accelerated the study and engineering of BSR genes in crops,which is the primary focus of this review.We first summarize recent advances in understanding the plant immune system,followed by an examination of the molecular mechanisms underlying BSR in crops.Finally,we highlight diverse strategies employed to achieve BSR,including gene stacking to combine multiple R genes,multiplexed genome editing of susceptibility genes and promoter regions of executor R genes,editing cis-regulatory elements to fine-tune gene expression,RNA interference,saturation mutagenesis,and precise genomic insertions.The genetic studies and engineering of BSR are accelerating the breeding of disease-resistant cultivars,contributing to crop improvement and enhancing global food security.展开更多
基金supported by National Key Research and Development Program of China(grant No.2022YFC0867500,2020YFA0712102)National Natural Science Foundation of China(grant No.82151224,82202492)+3 种基金Fundamental Research Funds for Central Universities(grant No.QNTD 2023-01)Nutrition and Care of Maternal&Child Research Project of Biostime Institute of Nutrition&Care(grant No.2023BINCMCF28)State Key Laboratory of Pathogen and Biosecurity of China(grant No.SKLPBS2438)State Key Laboratory of Component-based Chinese Medicine(grant No.CBCM2024204).
文摘Traditional Chinese medicine has unique advantages in preventing and treating COVID-19,and Fuzheng Jiedu decoction(FZJDD)was reported to be effective against COVID-19 in clinical trials.To investigate the potential mechanisms and material basis of FZJDD against SARS-CoV-2,we performed SARS-CoV-2 target protein inhibition analyses and a metabolite full spectrum analysis of FZJDD.Interestingly,FZJDD was found to block the binding of SARS-CoV-2 Spike protein with the receptor ACE2 and inhibit the activity of SARS-CoV-23CLpro.Moreover,FZJDD can regulate the TNF and the MAPK signaling pathway to inhibit the inflammatory response and alleviate the“cytokine storm”.A total of 298 compounds were identified in FZJDD,among them,caffeic acid and octyl gallate were found to be the potential therapeutic agents of FZJDD.Importantly,FZJDD can broadly inhibit coronavirus infection,including SADS-CoV and porcine epidemic diarrhea virus(PEDV)live viruses,SARS-CoV,MERS-CoV,and SARS-CoV-2 mutant pseudotyped viruses,which might be ascribed to the broad-spectrum anti-coronavirus activity of caffeic acid and octyl gallate.In conclusion,this study reveals the mechanisms and material basis of FZJDD against SARS-CoV-2 and identifies the broadspectrum anti-coronavirus activity of FZJDD for the first time.Our data provide empirical evidence for the development and application of FZJDD.
基金supported by the National Natural Science Foundation of China(Grant Nos.12475252,12175309,and 12175310)the Fund of National University of Defense Technology(Grant No.22-ZZCX-068)+1 种基金the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant Nos.XDA25050200 and XDA25010100)the Natural Science Foundation of Hunan Province,China(Grant No.2025JJ20007)。
文摘Displacement damage induced by high-energy protons in the space radiation environment presents a serious risk to the reliability of spacecraft materials and onboard electronics.Nevertheless,studies on displacement damage induced by spacebased broad-spectrum protons are still limited.In this paper,the nonionizing energy loss(NIEL)of space broad-spectrum protons at different orbital altitudes in semiconductor materials is investigated using Geant4 Monte Carlo simulations.We find that the NIEL of silicon(Si)and gallium arsenide(GaAs)first increases and then decreases with orbital altitude,and that shielding effects can result in either the saturation or continuous increase of NIEL,depending on the shielding layer thickness.A fast NIEL calculation method for arbitrary broad spectra is proposed based on statistical probability principles and the effective proton proportion.Meanwhile,a more uniform spatial distribution of mean damage energy per source particle(T_(dam))deposition from broad-spectrum protons can be achieved by increasing the shielding layer thickness and lowering the orbital altitude.Notably,the relative contribution of displacement damage caused by nuclear reactions decreases with increasing orbital altitude and shielding layer thickness.The results provide a quantitative reference for space displacement damage in semiconductor materials.
基金Supported by project of Beijing Municipal Education Commission(KM200910020014)Project of Sand Control Department,Beijing Municipal Landscape Greening Bureau(2008)~~
文摘[Objective] It is to clone broad-spectrum anti-disease gene NPR1 and to construct its protein expression vector.[Method] First to extract total RNA of Arabidopsis thaliana and design relevant primers,and then the method of reverse transcription PCR was adopted to clone.With the method of enzyme digestion and ligation,this gene will be directed into protein expression vector.[Result] After relevant testing,NPR1 was inserted into vector pMXB10 to obtain pMXB10-NPR1 protein expression vector.[Conclusion] Protein expression vector including NPR1 was successfully constructed.
基金supported by the Natural Science Foundation for Distinguished Young Scholars of Guangdong Province(No.2016A030306013)the Pearl River Young Talents Program of Science and Technology in Guangzhou(No.201906010047)the National Key Research and Development Program of China(No.2017YFA0205200)。
文摘Pathogen infection is the main cause of human morbidity and death.Traditional antibiotics usually sterilize bacteria in chemical ways,which tends to develop serious antibiotic resistance.Cationic polymers exhibit good bacterial inhibition with less resistance,but often face severe cytotoxicity toward normal cells.The optimization of polymeric antimicrobials for enhanced bactericidal capacity and improved biocompatibility is quite meaningful.In addition,photodynamic therapy(PDT)is a therapeutic modality with less susceptibility to develop resistance.Herein,a typical commercial polymeric antimicrobial,polyhexamethylene guanidine(PHMG)was selected for current proof-of-concept optimization due to its excellent bactericidal capacity but moderate biocompatibility.Eosin-Y(EoS)was copolymerized to afford EoS-labeled polymer conjugates,poly(2-(dimethylamino)ethyl methacrylate-co-eosin),P(DMAEMA-co-EoS),which was conjugated with PHMG to afford a novel polymeric antimicrobial,P(DMAEMA-co-EoS)-b-PHMG-b-P(DMAEMA-co-EoS),noted as PEoS-PHMG.It could efficiently kill broad-spectrum bacteria by physical damage and photodynamic therapy.Compared with PHMG,the bacterial inhibition of PEoS-PHMG was potentiated after the functionalization.Furthermore,PEoS-PHMG exhibited low cytotoxicity and minimal hemolysis,which was demonstrated by cell viability assays toward LO2 cells and RAW 264.7 cells as well as hemolytic assays against red blood cells.These results confirmed that the resultant PEoS-PHMG could act as promising alternative antibacterial materials with excellent broad-spectrum bacterial inhibition and favorable biocompatibility.
基金Supported by National Natural Science Foundation of China(31460341)Natural Science Foundation of Guangxi Province(2013GXNSFAA019060)Science and Technology Project of Guangxi Province(GK AB16380066)
文摘[ Objectives] Rice materials with broad-spectrum resistance against several pathogenic strains of Xanthomans oryzae pv. Oryzicola （Xooc） at multiple growth stages were screened, in order to provide reliable resistance sources for variety breeding against rice bacterial leaf streak. [ Methods] A total of 1 100 rice lines with rich genetic background were offered as selective objects, and highly susceptible cultivar Jingang 30 was used as the control. Inoculation was carried out with five strong pathogenic strains of Xooc through acupuncture method at various growth stages for resistance identification. [ Results] Fourteen disease-resistant materials were obtained through preliminary screening, accounting for 1.27% of the total materials. Nine materials moderately resistant to bacterial leaf streak were obtained via secondary screening, accounting for 0.82% of the total materials. Besides, three of them （ RL6, RL9 and RLL4） were resistant to a number of pathogenic strains of Xooc at three growth stages. In particular, RL16 presented broad-spectrum resistance to multi-strains with high resistance levels. Six of them （ RI2, RIA, RIS, RL8, RL11 and RL12） were resistant to single strain at single growth stage. [ Conclusions] The obtained three materials have broad-spectrum resistance to bacterial leaf streak at multiple growth stages, which can be served as an important source to cultivate disease-resistant rice varieties. RL6 maintains high broad-spectrum resistance at all growth stages, which can be used as a prior resistance source for rice variety breeding. Six materials obtained with resistance against bacterial leaf streak at particular growth stages can be used as candidate resistance sources.
基金funded by National Key R&D Program of China(No.2021YFE0200300)National Key R&D Program of China(No.2021YFC1712900).
文摘Coronaviruses exist widely in nature,can cause cross-species transmission,and pose serious threats to human and animal health.Over the past 20 years,coronaviruses have led to three major epidemics that have caused global panic,including severe acute respiratory syndrome,Middle East respiratory syndrome,and coronavirus disease-19.At present,coronavirus disease 19 not only spreads rapidly,but also mutates easily to escape host immune response,becoming more pathogenic.At present,there are no effective specific therapeutic drugs or vaccines.Drugs targeting severe acute respiratory syndrome coronavirus 2 and the host cell defense system that have been developed based on the structure and replication cycle of coronaviruses have a certain broad-spectrum antiviral effect;however,their efficacy still needs to be demonstrated in further clinical trials.Traditional Chinese medicine has an indispensable role in the ongoing response to coronavirus disease-19.Anti-virus treatment with traditional Chinese medicine has advantages such as broad-spectrum application,low toxicity and side effects,low susceptibility to drug resistance,and overall comprehensive regulation.Therefore,researches on effective components and mechanisms of action of the anti-viral effects of traditional Chinese medicine have increasingly gained attention.The present paper examines coronaviruses,specifically summarizing the genomes,replication mechanisms,and mutant strains.Afterward,the therapeutic effects and mechanisms of action of modern broad-spectrum anti-coronavirus drugs and traditional Chinese medicine are summarized.By considering the virus and the targets in the host comprehensively,in addition to the beneficial multi-target and multi-path antiviral effects of traditional Chinese medicines,this paper could guide the development of treatment strategies for broad-spectrum anti-coronavirus traditional Chinese medicines,and could facilitate the modernization and globalization of traditional Chinese medicine.
基金Supported by the Chang Gung Medical Research Project,No.CMRPG3M1931-1932the National Science and Technology Council,No.MOST 110-2314-B-182A-093-and No.NMRPG3L0331.
文摘Hepatic encephalopathy(HE)is a formidable complication in patients with decompensated cirrhosis,often necessitating the administration of rifaximin(RFX)for effective management.RFX,is a gut-restricted,poorly-absorbable oral rifamycin derived antibiotic that can be used in addition to lactulose for the secondary prophylaxis of HE.It has shown notable reductions in infection,hospital readmission,duration of hospital stay,and mortality.However,limited data exist about the concurrent use of RFX with broad-spectrum antibiotics,because the patients are typically excluded from studies assessing RFX efficacy in HE.A pharmacist-driven quasi-experimental pilot study was done to address this gap.They argue against the necessity of RFX in HE during broad-spectrum antibiotic treatment,particularly in critically ill patients in intensive care unit(ICU).The potential for safe RFX discontinuation without adverse effects is clearly illuminated and valuable insight into the optimization of therapeutic strategies is offered.The findings also indicate that RFX discontinuation during broadspectrum antibiotic therapy was not associated with higher rates of delirium or coma,and this result remained robust after adjustment in multivariate analysis.Furthermore,rates of other secondary clinical and safety outcomes,including ICU mortality and 48-hour changes in vasopressor requirements,were comparable.However,since the activity of RFX is mainly confined to the modulation of gut microbiota,its potential utility in patients undergoing extensive systemic antibiotic therapy is debatable,given the overlapping antibiotic activity.Further,this suggests that the action of RFX on HE is class-specific(related to its activity on gut microbiota),rather than drug-specific.A recent double-blind randomized controlled(ARiE)trial provided further evidence-based support for RFX withdrawal in critically ill cirrhotic ICU patients receiving broad-spectrum antibiotics.Both studies prompt further discussion about optimal therapeutic strategy for patients facing the dual challenge of HE and systemic infections.Despite these compelling results,both studies have limitations.A prospective,multi-center evaluation of a larger sample,with placebo control,and comprehensive neurologic evaluation of HE is warranted.It should include an exploration of longer-term outcome and the impact of this protocol in non-critically ill liver disease patients.
基金financial support from Natural Science Foundation of Henan Province(No.222300420501)the Key Scientific and Technological Project of Henan province(No.212102210549)+1 种基金the Key Scientific Research Project of Higher Education of Henan Province(No.22A430007)National College Students Innovation and Entrepreneurship Training Program(No.202210482028)。
文摘An amphiphilic AIE photosensitizer has been successfully developed,which allows for easily inserting into the bacterial membranes.Binding experiments with phospholipid preliminary demonstrates its membrane specificity.As expected,it is proved to possess a broad-spectrum bacterial staining performance and photodynamic antibacterial activity toward S.aureus and E.coli.
基金supported by the Strategic Priority Research Program of CAS(XDB29010300 to X.Z.)International Partnership Program of Chinese Academy of Sciences(153B42KYSB20200004 to X.Z.and R.W.)+3 种基金National Natural Science Foundation of China(21871301 to R.W.,81873964 to Y.Q.and 31970169 to X.Z.)Grant from the CAS Youth Innovation Promotion Association(2020332 to Y.Q.)the Science and Technology Development Fund,Macao SAR(0007/2020/A to R.W.)the Science and Technology Bureau of Wuhan(2018060401011309 to X.Z.)。
文摘The emergence and re-emergence of RNA virus outbreaks highlight the urgent need for the development of broadspectrum antivirals.Polyamines are positively-charged small molecules required for the infectivity of a wide range of RNA viruses,therefore may become good antiviral targets.Cucurbit[7]uril(CB[7]),a synthetic macrocyclic molecule,which can bind with amine-based organic compounds with high affinity,has been shown to regulate bioactive molecules through competitive binding.In this study,we tested the antiviral activity of CB[7]against diverse RNA viruses,including a panel of enteroviruses(i.e.human enterovirus A71,coxsackievirus A16,coxsackievirus B3,and echovirus 11),some flaviviruses(i.e.dengue virus and Zika virus),and an alphavirus representative Semliki forest virus.CB[7]can inhibit virus replications in a variety of cell lines,and its mechanism of action is through the competitive binding with polyamines.Our findings not only for the first time provide evidence that CB[7]can be a promising broad-spectrum antiviral agent,but more importantly,offer a novel therapeutic strategy to fight against RNA viruses by supramolecular sequestration of polyamines.
文摘Purpose: To investigate 1) the development in the incidence of ESBL-producing bacteria in hospitals and primary health care, 2) the contribution of primary health care to the incidence of ESBL-producing bacteria, and 3) the development in resistance patterns for all Escherichia coli and Klebsiella pneumoniae isolates in relation to antimicrobial consumption in hospitals and primary health care. Methods: ESBL-data were retrospectively collected from bacterial isolates from all specimens received at the Department of Clinical Microbiology from 2003 to 2011 together with the corresponding patient data. ESBL-production was detected in isolates from 1067 of 59,373 patients (1.8%) with an E. coli infection and in 263 of 8660 patients (3.0%) with a K. pneumoniae infection. Results: From 2003 to 2009, an increase in patients with an ESBL-producing isolate occurred in both hospitals and primary health care at the same time as an increased consumption of broad-spectrum antimicrobial agents was seen. Interventions to reduce prescription of cephalosporins and ciprofloxacin at the hospitals from 2010 resulted in a remarkable decrease in patients with ESBL-producing K. pneumoniae whereas a continuing increase was seen in patients with ESBL-producing E. coli both at hospitals and in primary health care. The proportion of patients with community-acquired ESBL-producing E. coli was stable with an increase of only 1.4% from 2007 to 2011. Conclusions: Reduction in prescription of broad-spectrum antimicrobial agents at the hospital level had an important impact on the incidence of ESBL-producing K. pneumoniae, but not on ESBL-producing E. coli.
基金Supported by Guangzhou Science and Technology Planning Project(202002030001)Fund for Modern Agro-Industry Technology Research System(CARS-01-32,2020KJ105)+1 种基金"Fourteenth Five-Year"New Discipline Team Building Project of Guangdong Academy of Agricultural Sciences(202116TD)Natural Science Foundation of Guangdong(2020A1515011213)。
文摘Yield loss caused by crop diseases seriously restricts global food security.Breeding disease-resistant varieties with resistance(R)genes is acknowledged as the most economical and effective way to control diseases.Therefore,exploring broad-spectrum resistance(BSR)genes to pathogens and clarifying the underlying mechanism are the basis for effective utilization of BSR resources and finding new approaches for disease control.In the past 20 years,significant progress has also been made in plant immune mechanism and remarkable achievements have been made in researches on broad-spectrum disease resistance of major grain crops,and the potential molecular mechanisms of some BSR have been revealed.Here,the advances of broad-spectrum disease resistance in rice(including the representative cloned BSR genes and their molecular mechanisms)were reviewed.In addition,the problems,opportunities and challenges encountered by BSR were analyzed,and the development of BSR research and its application in rice production were prospected.
文摘Hepatic encephalopathy(HE)is one of the main complications of cirrhosis,characterized by a wide spectrum of neuropsychiatric alterations that lead to an increase in mortality,morbidity and recurrent hospitalizations.Due to the central role in HE pathogenesis of ammonia and other neurotoxins primarily produced by the gut microbiota,the main therapeutic approaches for the treatment of HE are based on the modulation of the gut microbiota.Rifaximin is a non-absorbable broad-spectrum antibiotic,that is effective against ammonia-producing grampositive,gram-negative,and anaerobic species,approved for the treatment of HE in secondary prophylaxis.The chronic administration of rifaximin in this setting is associated with a lower risk of HE recurrence and mortality,while the role of rifaximin for the treatment of an overt-HE episode in inpatients is still unclear.Limited data exist about the coadministration of rifaximin and broad-spectrum antibiotics commonly used to treat concomitant infections,as patients receiving or recently treated with antibiotics were frequently excluded from clinical trials.In this editorial we comment on the article by Ward et al published in the recent issue of the World Journal of Hepatology.It is a single center,retrospective,quasiexperimental,pharmacist-driven protocol,with the aim to evaluate the feasibility and safety of rifaximin discontinuation in critically ill patients with HE and chronic liver disease receiving broad-spectrum antibiotic therapies in intensive care units.The study revealed no differences between the protocol and control group in terms of primary outcome(days alive and free of delirium and coma to day 14)and secondary outcomes which include:Intensive care mortality,intensive care length of stay,intravenous vasopressor requirement changes and adverse effects rate.Therefore,rifaximin discontinuation during broad-spectrum antibiotic therapy does not appear to negatively impact the clinical status of critically ill liver patients,with a similar safety profile and significant cost savings,as compared to the coadministration of rifaximin and broad-spectrum antibiotics.In agreement with Ward et al,a recently published double-blind,randomized controlled trial provided additional evidence to support the feasibility of withholding rifaximin during broad-spectrum antibiotic therapy in critically ill cirrhotic patients.However,given the limitations of these studies,further multicentric and prospective clinical trials,enrolling a larger sample of non-critically ill patients,are needed to better establish the role of rifaximin in this setting.
基金Zhangjiakou Science and Technology Tackling Program,No.2021099D.
文摘BACKGROUND Pediatric abdominal infection is a common but serious disease that requires timely and effective treatment.In surgical treatment,accurate diagnosis and rational application of antibiotics are the keys to improving treatment effects.AIM To investigate the effect of broad-spectrum bacterial detection on postoperative antibiotic therapy.METHODS A total of 100 children with abdominal infection who received surgical treatment in our hospital from September 2020 to July 2021 were grouped.The observation group collected blood samples upon admission and sent them for broad-spectrum bacterial infection nucleic acid testing,and collected pus or exudate during the operation for bacterial culture and drug sensitivity testing;the control group only sent bacterial culture and drug sensitivity testing during the operation.RESULTS White blood cell count,C-reactive protein,procalcitonin,3 days after surgery,showed better postoperative index than the control group(P<0.05).The hospital stay in the observation group was significantly shorter than that in the control group.The hospitalization cost in the observation group was significantly lower than that in the control group,and the difference between the two groups was statistically significant(P<0.05).CONCLUSION Early detection of broad-spectrum bacterial infection nucleic acids in pediatric abdominal infections can help identify pathogens sooner and guide the appropriate use of antibiotics,improving treatment outcomes and reducing medical costs to some extent.
文摘Chloasma, or melasma, is a commonly acquired pigmentary disorder among Asian women. It may be considered as a physiological change during pregnancy. The incidence in Asian women is higher than that in other ethnic groups but further epidemiologic data are needed. There are very few studies related to the benefits of sunscreens to prevent this dermatosis. The aim of this study was to assess the effectiveness of a broad-spectrum sunscreen in the prevention of melasma in Korean pregnant women. We tested the effectiveness and tolerance of a sunscreen product (SPF 50+, UVA-PF 30) during a 12-month clinical trial including 220 Korean parturients with skin type III and IV. 217 women completed the study. Only 3 (1%) of the study population developed melasma, which was mild (MASI grade between 1.2 and 2.7). In addition, the clinical effectiveness of the evaluated sunscreen was judged “good to excellent” by the majority of study participants and by the research dermatologists. The “excellent” tolerance of the sunscreen under evaluation was confirmed “good” to “excellent” in 95% and 97% of cases. This study clearly demonstrates that this broad-spectrum sunscreen is well tolerated and effective in the prevention of melasma in Korean pregnant women. Although treatment remains elusive, prevention is possible.
基金National Key Research and Development Program of China(Nos.2023YFC2606500 to X.Deng)National Natural Science Foundation of China(Nos.22377151 to X.Deng)+2 种基金the Hunan Provincial Key Research and Development Project(Nos.2021WK2005 to X.Deng)the Hunan Provincial Science Fund for Distinguished Young Scholars(Nos.2023JJ10083 to X.Deng)Huxiang High-Level Talent Gathering Project(Nos.2022RC4029)from the Science and Technology Department of Hunan province for the financial supports.
文摘Iminosugars,a class of polyhydroxylated cyclic alkaloids with intriguing properties,hold promising therapeutic potentials against a broad spectrum of enveloped viruses,including DENV,HCV,HIV,and influenza viruses.Mechanistically,iminosugars act as the competitive inhibitors of host endoplasmic reticularα-glucosidases I and II to disrupt the proper folding of viral nascent glycoproteins,which thereby exerts antiviral effects.Remarkably,the glycoproteins of many enveloped viruses are significantly more dependent on the calnexin pathway of the protein folding than most host glycoproteins.Therefore,extensive interests and efforts have been devoted to exploit iminosugars as broad-spectrum antiviral agents.This review provides the summary and insights into the recent advancements in the development of novel iminosugars as effective and selective antiviral agents against a variety of enveloped viruses,as well as the understandings of their antiviral mechanisms.
基金Supported by the following grant projects:LF_2012_006 and MSM6198959223.
文摘Strains of the Enterobacteriaceae family producing ESBL and AmpC broad-spectrum beta-lactamases that may survive in the hospital setting potentially cause infection in hospitalized patients due to contaminated objects or health care workers’ hands. Over a period of two months (November-December 2010), a single epidemiological study of microbial contamination of air, surfaces and health care workers (swabs from both nostrils and the right hand without a glove) was carried out at two intensive care units of the University Hospital Olomouc, Czech Republic. The bacteria were identified using standard microbiological methods. Phenotypic detection of ESBL and AmpC enzymes and basic genetic analysis of ESBL- and AmpC-positive isolates was performed. The same approach was used to identify and analyze bacteria isolated from clinical samples of patients hospitalized at the above departments over the study period. From a total of 140 environmental samples collected over the study period, 21 isolates of the Enterobacteriaceae family were identified, with ESBL and AmpC production being detected in 4 and 7 isolates, respectively. Among patients’ clinical samples, 10 ESBL- and 6 AmpC-positive isolates were detected. No similarity was found between environmental isolates and strains isolated from patients.
文摘A bacterial strain WY047 was isolated from fermented grains and the bacterium was identified as Bacillus amyloliquefaciens, based on morphological, biochemical, and physiological tests, and analysis of 16S rRNA and gyr A sequences. The culture supernatant of WY047 demonstrated inhibition ofa wide spectrum ofbacteria(Gram positive and Gram negative) and fungi. Nine pairs ofprimers were designed and six genes( bmyD, fenA, hag, ituA, mrsA, and tasA) ofantimicrobial substances were detected by PCR, one ofwhich was isolated by 80% ammonium sulfate precipitation, D201 resin anion-exchange chromatography, and Sephadex G-75 filtration column. The purified peptide was estimated to be 35,207 Da and identified as flagellin by MALDI-TOF mass spectrometry. Another four antimicrobial substances were extracted with methanol and identified as iturin A, fengycin, bacillomycin D, and mersacidin through the liquid chromatography–mass spectrometry(LC–MS) method. The sixth possible peptide encoded by tas A could not be isolated in this study; however, the broader spectrum suggested huge application prospects.
基金supported by the Key Research and Development Program,Ministry of Science and Technology of the People's Republic of China(No.2023YFC2606500).
文摘A recent study led by Yi-Wei Chang1,published in Science,integrates cryo-electron single-particle analysis(SPA)and cryo-electron tomography(cryo-ET)to elucidate the near-atomic architecture of the influenza virus ribonucleoprotein(RNP)complex.The study reveals that the RNP adopts a right-handed,antiparallel double-helical configuration,in which the viral RNA is translocated via a polymerase-driven strand sliding mechanism.Dynamic tail loop interactions between adjacent nucleoprotein(NP)subunits impart structural flexibility to the RNP,enabling conformational dynamics essential for processive RNA synthesis.These findings define a structural basis for strand sliding,and guided by this insight,the authors identify novel small molecules that disrupt NP–NP interactions by targeting a conserved tail loop interface,laying a foundation for broad-spectrum influenza antivirals.
基金financially supported by the National Natural Science Foundation of China(No.52073214)Guangxi Natural Science Fund for Distinguished Young Scholars(No.2024GXNSFFA010008).
文摘The operational efficiency of membrane electrode assemblies in direct liquid fuel cells is critically dependent on the fuel purity in the anode compartment.To address the inherent challenge of fuel mixing problem in alcohol systems,we propose a rational catalyst design strategy focusing on morphological and compositional optimization.Sodium borohydride-derived PtCuMo alloy aerogels(AA)exhibit abundant grain boundary defects,while solvothermally prepared nanowire arrays(NA)maintain excellent single-crystalline characteristics.Density functional theory calculations demonstrate that engineered grain boundaries can effectively broaden the adsorption energy window for key reaction intermediates,enabling superior adaptability to diverse catalytic pathways.By precisely controlling Cu content,we identified Pt_(3)Cu_(3)Mo_(0.5)AA as the optimal catalyst configuration,demonstrating 150% enhancement in methanol oxidation reaction activity compared to Pt_(3)Cu_(6)Mo_(0.5)NA(1.5 vs.0.6 A·mg_(Pt)^(-1))and 17% improvement in ethanol oxidation reaction performance versus Pt_(3)Cu_(1)Mo_(0.5)NA(0.82 vs.0.70 A·mg_(Pt)^(-1)).Practical application testing using gas diffusion electrodes(anode loading:0.85 mg_(Pt)·cm^(-2))achieved a mass-specific power density of 14.14 W·g_(Pt)^(-1)in 1:1 methanol/ethanol blends,representing a 3.5-fold improvement over commercial Pt/C benchmarks.This work establishes a fundamental framework for developing highperformance,broad-spectrum electrocatalysts in advanced fuel cell systems.
基金supported by Biological Breeding-National Science and Technology Major Projects(2023ZD04070)the Key R&D Program of Hubei Province(2023BBB171)+3 种基金the National Key R&D Program of China(2022YFA1304402)Fundamental Research Funds for the Central Universities(2662023PY006,AML2023A05,2662024ZKPY001)(to G.L.)supported by the Fundamental Research Funds for the Central Universities(2662023PY006)(to K.X.)supported by the National Natural Science Foundation of China(32172373 and 32293243)(to G.L.and K.X.,respectively)and Hubei Hongshan Laboratory.
文摘Plant diseases,caused by a wide range of pathogens,severely reduce crop yield and quality,posing a significant threat to global food security.Developing broad-spectrum resistance(BSR)in crops is a key strategy for controlling crop diseases and ensuring sustainable crop production.Cloning disease-resistance(R)genes and understanding their underlying molecular mechanisms provide new genetic resources and strategies for crop breeding.Novel genetic engineering and genome editing tools have accelerated the study and engineering of BSR genes in crops,which is the primary focus of this review.We first summarize recent advances in understanding the plant immune system,followed by an examination of the molecular mechanisms underlying BSR in crops.Finally,we highlight diverse strategies employed to achieve BSR,including gene stacking to combine multiple R genes,multiplexed genome editing of susceptibility genes and promoter regions of executor R genes,editing cis-regulatory elements to fine-tune gene expression,RNA interference,saturation mutagenesis,and precise genomic insertions.The genetic studies and engineering of BSR are accelerating the breeding of disease-resistant cultivars,contributing to crop improvement and enhancing global food security.
