A simple and rapid expression and purification method of recombinant firefly luciferase was developed for bacteria detection.A modified luciferase gene from North American firefly Photinus pyralis was cloned into pET2...A simple and rapid expression and purification method of recombinant firefly luciferase was developed for bacteria detection.A modified luciferase gene from North American firefly Photinus pyralis was cloned into pET28a expression vector and the recombinant protein was produced in Escherichia coli BL21.The recombinant luciferase,equipped with a polyhistidine affinity tag,was purified by immobilized metal ion affinity chromatography(IMAC).The approach generated an abundant expression and an efficient purification of a recombinant luciferase with final yield 1.995mg/L of cell culture.Experiments on the recombinant luciferase also showed that the relative light units(RUL)of the enzyme were 5.8×108,and the specific activity was 2.9×1010 RLU/mg.By applying adenosine triphosphate(ATP)bioluminescence to detection of the coin bacteria using the recombinant protein,the ATP content of bacteria was 9.48×10-16mol/mL,and was identical to the bacteria counts(4500CFU/mL)in order of magnitude.Taken together,our results provided a simple and efficacious method of the preparation of recombinant luciferase,which could be applied in the determination of bacteria via ATP bioluminescence.展开更多
Accurate and efficient bacterial detection is essential for public health and medical diagnostics. However, traditional detection methods are constrained by limited dataset size, complex bacterial morphology, and dive...Accurate and efficient bacterial detection is essential for public health and medical diagnostics. However, traditional detection methods are constrained by limited dataset size, complex bacterial morphology, and diverse detection environments, hindering their effectiveness. In this study, we present EagleEyeNet, a novel multi-scale information fusion model designed to address these challenges. EagleEyeNet leverages large models as teacher networks in a knowledge distillation framework, significantly improving detection performance. Additionally, a newly designed feature fusion architecture, integrating Transformer modules, is proposed to enable the efficient fusion of global and multi-scale features, overcoming the bottlenecks posed by Feature Pyramid Networks (FPN) structures, which in turn reduces information transmission loss between feature layers. To improve the model’s adaptability for different scenarios, we create our own QingDao Bacteria Detection (QDBD) dataset as a comprehensive evaluation benchmark for bacterial detection. Experimental results demonstrate that EagleEyeNet achieves remarkable performance improvements, with mAP50 increases of 3.1% on the QDBD dataset and 4.9% on the AGRA dataset, outperforming the State-Of-The-Art (SOTA) methods in detection accuracy. These findings underscore the transformative potential of integrating large models and deep learning for advancing bacterial detection technologies.展开更多
Pathogenic and corrosive bacteria pose a significant risk to human health or economic well-being.The specific,sensitive,and on-site detection of these bacteria is thus of paramount significance but remains challenging...Pathogenic and corrosive bacteria pose a significant risk to human health or economic well-being.The specific,sensitive,and on-site detection of these bacteria is thus of paramount significance but remains challenging.Taking inspiration from immunoassays with primary and secondary antibodies,we describe here a rational design of microbial sensor(MS)under a dualspecificity recognition strategy using Pseudomonas aeruginosa(P.aeruginosa)as the detection model.In the MS,engineered aptamers are served as the primary recognition element,while polydopamine-N-acetyl-D-galactosamine(PDA-Gal NAc)nanoparticles are employed as the secondary recognition element,which will also generate and amplify changes in the output voltage signal.To achieve self-powering capability,the MS is constructed based on a triboelectric nanogenerator(TENG)with the specific aptamers immobilized on the TENG electrode surface.The as-prepared MS-TENG system exhibits good stability in output performance under external forces,and high specificity toward P.aeruginosa,with no cross-reactivity observed.A linear relationship(R^(2)=0.995)between the output voltage and P.aeruginosa concentration is established,with a limit of detection estimated at around 8.7×10^(3) CFU mL^(-1).The utilization of PDA-Gal NAc nanoparticles is found to play an important role in enhancing the specific and reliability of detection,and the underlying mechanisms are further clarified by computational simulations.In addition,the MS-TENG integrates a wireless communication module,enabling real-time monitoring of bacterial concentration on mobile devices.This work introduces a pioneering approach to designing self-powered smart microbial sensors with high specificity,using a double recognition strategy applicable to various bacteria beyond P.aeruginosa.展开更多
Establishing a system for measuring plant health and bacterial infection is critical in agriculture.Previously,the farmers themselves,who observed them with their eyes and relied on their experience in analysis,which ...Establishing a system for measuring plant health and bacterial infection is critical in agriculture.Previously,the farmers themselves,who observed them with their eyes and relied on their experience in analysis,which could have been incorrect.Plant inspection can determine which plants reflect the quantity of green light and near-infrared using infrared light,both visible and eye using a drone.The goal of this study was to create algorithms for assessing bacterial infections in rice using images from unmanned aerial vehicles(UAVs)with an ensemble classification technique.Convolution neural networks in unmanned aerial vehi-cles image were used.To convey this interest,the rice’s health and bacterial infec-tion inside the photo were detected.The project entailed using pictures to identify bacterial illnesses in rice.The shape and distinct characteristics of each infection were observed.Rice symptoms were defined using machine learning and image processing techniques.Two steps of a convolution neural network based on an image from a UAV were used in this study to determine whether this area will be affected by bacteria.The proposed algorithms can be utilized to classify the types of rice deceases with an accuracy rate of 89.84 percent.展开更多
creening of foodborne pathogens is important to prevent contaminated foods from their supply chains.n this study, a portable detection device was developed for rapid, sensitive and simple detection of viable almonella...creening of foodborne pathogens is important to prevent contaminated foods from their supply chains.n this study, a portable detection device was developed for rapid, sensitive and simple detection of viable almonella using a finger-actuated microfluidic chip and an improved recombinase aided amplification (RAA) assay. Improved propidium monoazide(PMAxx) was combined with RAA to enable this device to distinguish viable bacteria from dead ones. The modification of PMAxx into dead bacteria, the magnetic xtraction of nucleic acids from viable bacteria and the RAA detection of extracted nucleic acids were performed using the microfluidic chip on its supporting device by finger press-release operations. The fluorescent signal resulting from RAA amplification of the nucleic acids was collected using a USB camera nd analyzed using a self-developed smartphone App to quantitatively determine the bacterial concenration. This device could detect Salmonella typhimurium in spiked chicken meats from 1.3 × 10^(2) CFU/m L o 1.3 × 10^(7) CFU/m L in 2 h with a lower detection limit of 130 CFU/m L, and has shown its potential for on-site detection of foodborne pathogens.展开更多
Plasmonic metal nanomaterials with intrinsic surface–enhanced Raman scattering(SERS)and photothermal properties,especially AuAg nanoalloys with both the outstanding merits of Au and Ag nanocrystals,show huge applicat...Plasmonic metal nanomaterials with intrinsic surface–enhanced Raman scattering(SERS)and photothermal properties,especially AuAg nanoalloys with both the outstanding merits of Au and Ag nanocrystals,show huge application prospects in bacterial theranostics.However,the direct exposure of AuAg nanoalloys in external conditions probably cause undesirable reactions and poisonous metal ion leakage during SERS detection and photothermal antibacterial therapy process,which severely hinder bacterial theranostics applications.Herein,we report an ultrastable graphene–isolated AuAg nanoalloy(GAA)with AuAg core confined in few–layer graphitic shell as a versatile platform for bacterial detection and therapy.The encapsulation of graphene ensures the good stability of AuAg core,that its superior SERS and photothermal properties are therefore further guaranteed.GAA is used for SERS detection of two vital bacterial biomarkers(including corrosive cyanide and pyocyanin),exhibiting good SERS quantitative and multiplexing ability.GAA is further used for photothermal antibacterial therapy application,and ultrahigh antibacterial efficacies for both Gram–negative Escherichia coli and Gram–positive Staphylococcus aureus are achieved under 808 nm laser irradiation.This work proposes a valuable method to develop robust bacterial theranostic platform.展开更多
BACKGROUND Diagnosing and treating abdominal infection in children remains a challenge.Nucleic acid detection,as a rapid and accurate diagnosis tool,has great significance in this field.AIM To investigate the diagnosi...BACKGROUND Diagnosing and treating abdominal infection in children remains a challenge.Nucleic acid detection,as a rapid and accurate diagnosis tool,has great significance in this field.AIM To investigate the diagnosis and treatment of abdominal infection by nucleic acid detection and its possible correlation with psychological stress in children.METHODS A total of 50 pediatric patients diagnosed with abdominal infections between September 2020 and July 2021 were included in this study.Intra-abdominal pus samples were collected for pathogen culture,drug susceptibility testing,and broad-spectrum bacterial nucleic acid testing.Psychological stress,anxiety,depression,and coping styles were assessed using the coping with a disease(CODI)scale.RESULTS Based on susceptibility testing,a regimen of cefazoxime,piperacillin/tazobactam,and metronidazole or ornidazole achieved 100%effectiveness in treating appendicitis.Psychological assessments revealed a positive correlation between pressure level and both anxiety(r=0.324,P=0.001)and depressive disorders(r=0.325,P<0.001).Acceptance and distancing as coping strategies were negatively correlated with anxiety and depression,while negative emotional responses were strongly associated with increased anxiety(r=0.574,P<0.001)and depression(r=0.511,P=0.001).Coping strategies such as illusion and escape showed no significant correlation with emotional outcomes.CONCLUSION Nucleic acid testing helps in the diagnosis of abdominal infections in children,and also focuses on children's mental health.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
Pathogenic bacterial infections pose major health threats and economic burdens.Rapid and highly sensitive biochemical sensors are essential for bacterial detection in food safety and clinical applications.Here,we intr...Pathogenic bacterial infections pose major health threats and economic burdens.Rapid and highly sensitive biochemical sensors are essential for bacterial detection in food safety and clinical applications.Here,we introduce a graphene oxide(GO)-based magnetic nanomechanical array sensor that utilizes the large surface area of GO to bind more magnetic nanoparticles(MNPs)and aptamers.Rapid and ultra-sensitive detection can be achieved even at extremely low target concentrations.This approach can directly detect a single Escherichia coli cell without time-consuming bacterial culture,and the linear detection range is 1-100 CFU·mL-1.Meanwhile,the sensor showed good specificity,reproducibility,stability,and stance to interference,and could detect 1 CFU·mL^(-1) Escherichia coli in milk.Moreover,we realized the simultaneous detection of two bacteria at extremely low concentrations,which proved that the sensor had the potential for high-throughput detection.In addition,for extremely low-concentration samples(<100 CFU·mL^(-1)),we controlled the magnetic force at the tip of the microcantilever,greatly enhancing its deflection and sensitivity.This method provides a novel and ultrasensitive method for the timely detection of pathogenic bacteria,and can also be applied to the highly sensitive detection of other targets such as DNA,small molecules,proteins,and viruses by using different probes.Our research provides a promising tool for effective,rapid and highly sensitive detection in the field of public health and food safety.展开更多
Continuous,real-time monitoring and identification of bacteria through detection of microbially emitted volatile molecules are highly sought albeit elusive goals.We introduce an artificial nose for sensing and disting...Continuous,real-time monitoring and identification of bacteria through detection of microbially emitted volatile molecules are highly sought albeit elusive goals.We introduce an artificial nose for sensing and distinguishing vapor molecules,based upon recording the capacitance of interdigitated electrodes(IDEs)coated with carbon dots(C-dots)exhibiting different polarities.Exposure of the C-dot-IDEs to volatile molecules induced rapid capacitance changes that were intimately dependent upon the polarities of both gas molecules and the electrode-deposited C-dots.We deciphered the mechanism of capacitance transformations,specifically substitution of electrode-adsorbed water by gas molecules,with concomitant changes in capacitance related to both the polarity and dielectric constants of the vapor molecules tested.The C-dot-IDE gas sensor exhibited excellent selectivity,aided by application of machine learning algorithms.The capacitive C-dot-IDE sensor was employed to continuously monitor microbial proliferation,discriminating among bacteria through detection of distinctive“volatile compound fingerprint”for each bacterial species.The C-dot-IDE platform is robust,reusable,readily assembled from inexpensive building blocks and constitutes a versatile and powerful vehicle for gas sensing in general,bacterial monitoring in particular.展开更多
Rapid detection of foodborne pathogens is crucial to prevent the outbreaks of foodborne diseases.In this work,we proposed a novel microfluidic biosensor based on magnetorheological elastomer(MRE)and smartphone.First,m...Rapid detection of foodborne pathogens is crucial to prevent the outbreaks of foodborne diseases.In this work,we proposed a novel microfluidic biosensor based on magnetorheological elastomer(MRE)and smartphone.First,micropump and microvalves were constructed by deforming the MRE under magnetic actuation and integrated into the microfluidic biosensor for fluidic control.Then,the micropump was used to deliver immune porous gold@platinum nanocatalysts(Au@PtNCs),bacterial sample,and immunomagnetic nanoparticles(MNPs)into a micromixer,where they were mixed,incubated and magnetically separated to obtain the Au@PtNC-bacteria-MNP complexes.After 3,3',5,5'-tetramethylbenzidine and hydrogen peroxide were injected and catalyzed by the Au@PtNCs,smartphone was used to measure the color of the catalysate for quantitative analysis of target bacteria.Under optimal conditions,this biosensor could detect Salmonella typhimurium quantitatively and automatically in 1 h with a linear detection range of 8.0×10^(1) CFU/mL to 8.0×10^(4) CFU/mL and a detection limit of 62 CFU/mL.The microfluidic biosensor was compact in size,simple to use,and efficient for detection,and might be used for in-field screening of foodborne pathogens to prevent food poisoning.展开更多
A novel inductance-based sensing technique is presented for remote query measurement in different liquid media including organic solvents and inorganic solutions.The inorganic solutions tested included salt solutions ...A novel inductance-based sensing technique is presented for remote query measurement in different liquid media including organic solvents and inorganic solutions.The inorganic solutions tested included salt solutions of different concentrations,and the organic solvents detected included 1,4-dioxane and tetrahydrofuran.To extend the application of the sensor,bacterial culture media were also detected,and the growth of Escherichia coli(E.coli)was controlled.The influential factors which may affect the inductance responses were studied in detail.It was found that quantitative relationships exist between the sensor’s inductance response and the physico-chemical parameters of the liquid media.The sensor’s inductance response(L)decreases with the increase of salt concentration(C)and its ionic valence(e)according to a semi-logarithmic equation LgL=-aeC+b,where a and b are constants,which is in accordance with the theoretically deduced equation.The inductance variation rate(ΔK)increases directly with the temperature(T):ΔK=a′T+b′.As for organic solutions,the sensor’s inductance was found to increase with the increasing permittivity of the organic solution.The wireless sensor we designed is simple and easy to manipulate.It has the potential for remote determination of not only chemical substances but also microbiological species such as bacteria.Using the newly developed inductance-based sensor,the pathogenic E.coli was monitored with a limit of detection of 10 cells/mL and a linear semi-logarithmic range of 1.0×101 to 2.5×109 cells/mL.展开更多
The rise of resistance to all known antibiotics is a global crisis.In addition to novel treatment options,there is an urgent need to develop rapid,specific,sensitive,and reliable diagnostic methods to detect pathogeni...The rise of resistance to all known antibiotics is a global crisis.In addition to novel treatment options,there is an urgent need to develop rapid,specific,sensitive,and reliable diagnostic methods to detect pathogenic bacteria in clinical samples and reduce the overuse and misuse antibiotics.Pseudopaline,a metallophore produced by the human pathogen Pseudomonas aeruginosa,transports divalent metal ions via a dedicated active transport system,making it an ideal carrier for a second functional moiety.展开更多
Impedance measurements using graphite electrodes were used to detect the increase in culture medium conductivity due to bacteria growth in real time along with simultaneous voltammetric monitoring of pyocyanin concent...Impedance measurements using graphite electrodes were used to detect the increase in culture medium conductivity due to bacteria growth in real time along with simultaneous voltammetric monitoring of pyocyanin concentration.Electrochemical methods were compared to conventional continuous monitoring of bacterial cultures using turbidity measurement at an optical density of 600 nm(OD600).A practical osmotic system was further designed for concentrating bacterial cultures during growth to enable earlier detection using the electrochemical methods.Bacterial cultures,starting from an initial culture density of 1×10^(8) cells/mL,were grown inside a sealed cellulose ester dialysis membrane,while polyethylene glycol in LB medium was used as the draw solution outside the membrane to gradually concentrate the growing cultures.0.7-mm-diameter graphite for mechanical pencils was utilized as working and counter electrodes with a platinum wire reference electrode for electrochemical measurements with and without the osmotic system.In the absence of forward osmosis,impedance meas-urements detected culture growth~1 h faster than conventional OD600.Integrating osmosis showed a twofold decrease in the time to detect pyocyanin production as an indicator for bacterial growth.For impedance monitoring,removal of water by osmosis was conflated with the impedance decrease due to cell growth;however,the results show a promising ability to detect bacteria growth via an observed shift in osmotic impedance profile when bacteria are present in a sample.By monitoring the deviation in the impedance profile,a threefold improvement in detection time was achieved when compared to conventional OD600 measurements.展开更多
Bacterial resistance,primarily stemming from misdiagnosis,misuse,and overuse of antibacterial medications in humans and animals,is a pressing issue.To address this,we focused on developing a fluorescent probe for the ...Bacterial resistance,primarily stemming from misdiagnosis,misuse,and overuse of antibacterial medications in humans and animals,is a pressing issue.To address this,we focused on developing a fluorescent probe for the detection of bacteria,with a unique feature--an exceptionally long fluorescence lifetime,to overcome autofluorescence limitations in biological samples.The polymyxin-based probe(ADOTA-PMX)selectively targets Gram-negative bacteria and used the red-emitting fluorophore azadioxatriangulenium(with a reported fluorescence lifetime of 19.5 ns).Evaluation of ADOTA-PMX’s bacterial labeling efficacy revealed strong specificity for Gram-negative bacteria,and full spectral fluorescence lifetime imaging microscopy demonstrated the potential of ADOTA-PMX for bacterial imaging applications.The probe exhibited a lifetime of 4.5 ns when bound to bacteria,possibly indicating interactions with the bacterial outer membrane.Furthermore,the fluorescence lifetime measurements of ADOTA-PMX labeled bacteria could be performed using a benchtop fluorimeter without the need of sophisticated microscopes.This study represents the first targeted probe for fluorescence lifetime imaging,offering sensitivity for detecting Gram-negative bacteria and enabling multiplexing via fluorescence lifetime imaging.展开更多
基金supported by the National Key Technology R&D Program(2006BAK02A13)the National Basic Research Program of China(973Program,No.2007CB714507)
文摘A simple and rapid expression and purification method of recombinant firefly luciferase was developed for bacteria detection.A modified luciferase gene from North American firefly Photinus pyralis was cloned into pET28a expression vector and the recombinant protein was produced in Escherichia coli BL21.The recombinant luciferase,equipped with a polyhistidine affinity tag,was purified by immobilized metal ion affinity chromatography(IMAC).The approach generated an abundant expression and an efficient purification of a recombinant luciferase with final yield 1.995mg/L of cell culture.Experiments on the recombinant luciferase also showed that the relative light units(RUL)of the enzyme were 5.8×108,and the specific activity was 2.9×1010 RLU/mg.By applying adenosine triphosphate(ATP)bioluminescence to detection of the coin bacteria using the recombinant protein,the ATP content of bacteria was 9.48×10-16mol/mL,and was identical to the bacteria counts(4500CFU/mL)in order of magnitude.Taken together,our results provided a simple and efficacious method of the preparation of recombinant luciferase,which could be applied in the determination of bacteria via ATP bioluminescence.
基金supported by the Shandong Provincial Department of Education.
文摘Accurate and efficient bacterial detection is essential for public health and medical diagnostics. However, traditional detection methods are constrained by limited dataset size, complex bacterial morphology, and diverse detection environments, hindering their effectiveness. In this study, we present EagleEyeNet, a novel multi-scale information fusion model designed to address these challenges. EagleEyeNet leverages large models as teacher networks in a knowledge distillation framework, significantly improving detection performance. Additionally, a newly designed feature fusion architecture, integrating Transformer modules, is proposed to enable the efficient fusion of global and multi-scale features, overcoming the bottlenecks posed by Feature Pyramid Networks (FPN) structures, which in turn reduces information transmission loss between feature layers. To improve the model’s adaptability for different scenarios, we create our own QingDao Bacteria Detection (QDBD) dataset as a comprehensive evaluation benchmark for bacterial detection. Experimental results demonstrate that EagleEyeNet achieves remarkable performance improvements, with mAP50 increases of 3.1% on the QDBD dataset and 4.9% on the AGRA dataset, outperforming the State-Of-The-Art (SOTA) methods in detection accuracy. These findings underscore the transformative potential of integrating large models and deep learning for advancing bacterial detection technologies.
基金National Natural Science Foundation of China,Grant/Award Number:42276216Natural Science Foundation of Guangxi Province,Grant/Award Number:2023GXNSFDA026059。
文摘Pathogenic and corrosive bacteria pose a significant risk to human health or economic well-being.The specific,sensitive,and on-site detection of these bacteria is thus of paramount significance but remains challenging.Taking inspiration from immunoassays with primary and secondary antibodies,we describe here a rational design of microbial sensor(MS)under a dualspecificity recognition strategy using Pseudomonas aeruginosa(P.aeruginosa)as the detection model.In the MS,engineered aptamers are served as the primary recognition element,while polydopamine-N-acetyl-D-galactosamine(PDA-Gal NAc)nanoparticles are employed as the secondary recognition element,which will also generate and amplify changes in the output voltage signal.To achieve self-powering capability,the MS is constructed based on a triboelectric nanogenerator(TENG)with the specific aptamers immobilized on the TENG electrode surface.The as-prepared MS-TENG system exhibits good stability in output performance under external forces,and high specificity toward P.aeruginosa,with no cross-reactivity observed.A linear relationship(R^(2)=0.995)between the output voltage and P.aeruginosa concentration is established,with a limit of detection estimated at around 8.7×10^(3) CFU mL^(-1).The utilization of PDA-Gal NAc nanoparticles is found to play an important role in enhancing the specific and reliability of detection,and the underlying mechanisms are further clarified by computational simulations.In addition,the MS-TENG integrates a wireless communication module,enabling real-time monitoring of bacterial concentration on mobile devices.This work introduces a pioneering approach to designing self-powered smart microbial sensors with high specificity,using a double recognition strategy applicable to various bacteria beyond P.aeruginosa.
基金funded by King Mongkut’s University of Technology North Bangkok(Contract no.KMUTNB-63-KNOW-044).
文摘Establishing a system for measuring plant health and bacterial infection is critical in agriculture.Previously,the farmers themselves,who observed them with their eyes and relied on their experience in analysis,which could have been incorrect.Plant inspection can determine which plants reflect the quantity of green light and near-infrared using infrared light,both visible and eye using a drone.The goal of this study was to create algorithms for assessing bacterial infections in rice using images from unmanned aerial vehicles(UAVs)with an ensemble classification technique.Convolution neural networks in unmanned aerial vehi-cles image were used.To convey this interest,the rice’s health and bacterial infec-tion inside the photo were detected.The project entailed using pictures to identify bacterial illnesses in rice.The shape and distinct characteristics of each infection were observed.Rice symptoms were defined using machine learning and image processing techniques.Two steps of a convolution neural network based on an image from a UAV were used in this study to determine whether this area will be affected by bacteria.The proposed algorithms can be utilized to classify the types of rice deceases with an accuracy rate of 89.84 percent.
基金funded by National Natural Science Foundation of China (No. 32071899)Walmart Foundation (No. UA2020– 154)。
文摘creening of foodborne pathogens is important to prevent contaminated foods from their supply chains.n this study, a portable detection device was developed for rapid, sensitive and simple detection of viable almonella using a finger-actuated microfluidic chip and an improved recombinase aided amplification (RAA) assay. Improved propidium monoazide(PMAxx) was combined with RAA to enable this device to distinguish viable bacteria from dead ones. The modification of PMAxx into dead bacteria, the magnetic xtraction of nucleic acids from viable bacteria and the RAA detection of extracted nucleic acids were performed using the microfluidic chip on its supporting device by finger press-release operations. The fluorescent signal resulting from RAA amplification of the nucleic acids was collected using a USB camera nd analyzed using a self-developed smartphone App to quantitatively determine the bacterial concenration. This device could detect Salmonella typhimurium in spiked chicken meats from 1.3 × 10^(2) CFU/m L o 1.3 × 10^(7) CFU/m L in 2 h with a lower detection limit of 130 CFU/m L, and has shown its potential for on-site detection of foodborne pathogens.
基金funding support from the National Key Research and Development Program of China(Nos.2022YFC2403501,2020YFA0210800)National Natural Science Foundation of China(No.22225401)+1 种基金Science and Technology Innovation Program of Hunan Province(No.2020RC4017)China Postdoctoral Science Foundation(No.2021M701145)。
文摘Plasmonic metal nanomaterials with intrinsic surface–enhanced Raman scattering(SERS)and photothermal properties,especially AuAg nanoalloys with both the outstanding merits of Au and Ag nanocrystals,show huge application prospects in bacterial theranostics.However,the direct exposure of AuAg nanoalloys in external conditions probably cause undesirable reactions and poisonous metal ion leakage during SERS detection and photothermal antibacterial therapy process,which severely hinder bacterial theranostics applications.Herein,we report an ultrastable graphene–isolated AuAg nanoalloy(GAA)with AuAg core confined in few–layer graphitic shell as a versatile platform for bacterial detection and therapy.The encapsulation of graphene ensures the good stability of AuAg core,that its superior SERS and photothermal properties are therefore further guaranteed.GAA is used for SERS detection of two vital bacterial biomarkers(including corrosive cyanide and pyocyanin),exhibiting good SERS quantitative and multiplexing ability.GAA is further used for photothermal antibacterial therapy application,and ultrahigh antibacterial efficacies for both Gram–negative Escherichia coli and Gram–positive Staphylococcus aureus are achieved under 808 nm laser irradiation.This work proposes a valuable method to develop robust bacterial theranostic platform.
基金Supported by Zhangjiakou Science and Technology Tackling Program,No.2021099D。
文摘BACKGROUND Diagnosing and treating abdominal infection in children remains a challenge.Nucleic acid detection,as a rapid and accurate diagnosis tool,has great significance in this field.AIM To investigate the diagnosis and treatment of abdominal infection by nucleic acid detection and its possible correlation with psychological stress in children.METHODS A total of 50 pediatric patients diagnosed with abdominal infections between September 2020 and July 2021 were included in this study.Intra-abdominal pus samples were collected for pathogen culture,drug susceptibility testing,and broad-spectrum bacterial nucleic acid testing.Psychological stress,anxiety,depression,and coping styles were assessed using the coping with a disease(CODI)scale.RESULTS Based on susceptibility testing,a regimen of cefazoxime,piperacillin/tazobactam,and metronidazole or ornidazole achieved 100%effectiveness in treating appendicitis.Psychological assessments revealed a positive correlation between pressure level and both anxiety(r=0.324,P=0.001)and depressive disorders(r=0.325,P<0.001).Acceptance and distancing as coping strategies were negatively correlated with anxiety and depression,while negative emotional responses were strongly associated with increased anxiety(r=0.574,P<0.001)and depression(r=0.511,P=0.001).Coping strategies such as illusion and escape showed no significant correlation with emotional outcomes.CONCLUSION Nucleic acid testing helps in the diagnosis of abdominal infections in children,and also focuses on children's mental health.
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.
基金the National Natural Science Foundation of China(Nos.12232017,12222212,and 12072339)is gratefully acknowledged.
文摘Pathogenic bacterial infections pose major health threats and economic burdens.Rapid and highly sensitive biochemical sensors are essential for bacterial detection in food safety and clinical applications.Here,we introduce a graphene oxide(GO)-based magnetic nanomechanical array sensor that utilizes the large surface area of GO to bind more magnetic nanoparticles(MNPs)and aptamers.Rapid and ultra-sensitive detection can be achieved even at extremely low target concentrations.This approach can directly detect a single Escherichia coli cell without time-consuming bacterial culture,and the linear detection range is 1-100 CFU·mL-1.Meanwhile,the sensor showed good specificity,reproducibility,stability,and stance to interference,and could detect 1 CFU·mL^(-1) Escherichia coli in milk.Moreover,we realized the simultaneous detection of two bacteria at extremely low concentrations,which proved that the sensor had the potential for high-throughput detection.In addition,for extremely low-concentration samples(<100 CFU·mL^(-1)),we controlled the magnetic force at the tip of the microcantilever,greatly enhancing its deflection and sensitivity.This method provides a novel and ultrasensitive method for the timely detection of pathogenic bacteria,and can also be applied to the highly sensitive detection of other targets such as DNA,small molecules,proteins,and viruses by using different probes.Our research provides a promising tool for effective,rapid and highly sensitive detection in the field of public health and food safety.
基金We are grateful to Dr.Natalya Froumin(XPS),Dr.Yanna Milionshi(TGA),Dr.Jurgen Jopp(AFM),Dr.Igor Mokmanov for assistance with GC-MS experiments and Mrs.Galia Strinkovski for mentoring.
文摘Continuous,real-time monitoring and identification of bacteria through detection of microbially emitted volatile molecules are highly sought albeit elusive goals.We introduce an artificial nose for sensing and distinguishing vapor molecules,based upon recording the capacitance of interdigitated electrodes(IDEs)coated with carbon dots(C-dots)exhibiting different polarities.Exposure of the C-dot-IDEs to volatile molecules induced rapid capacitance changes that were intimately dependent upon the polarities of both gas molecules and the electrode-deposited C-dots.We deciphered the mechanism of capacitance transformations,specifically substitution of electrode-adsorbed water by gas molecules,with concomitant changes in capacitance related to both the polarity and dielectric constants of the vapor molecules tested.The C-dot-IDE gas sensor exhibited excellent selectivity,aided by application of machine learning algorithms.The capacitive C-dot-IDE sensor was employed to continuously monitor microbial proliferation,discriminating among bacteria through detection of distinctive“volatile compound fingerprint”for each bacterial species.The C-dot-IDE platform is robust,reusable,readily assembled from inexpensive building blocks and constitutes a versatile and powerful vehicle for gas sensing in general,bacterial monitoring in particular.
文摘Rapid detection of foodborne pathogens is crucial to prevent the outbreaks of foodborne diseases.In this work,we proposed a novel microfluidic biosensor based on magnetorheological elastomer(MRE)and smartphone.First,micropump and microvalves were constructed by deforming the MRE under magnetic actuation and integrated into the microfluidic biosensor for fluidic control.Then,the micropump was used to deliver immune porous gold@platinum nanocatalysts(Au@PtNCs),bacterial sample,and immunomagnetic nanoparticles(MNPs)into a micromixer,where they were mixed,incubated and magnetically separated to obtain the Au@PtNC-bacteria-MNP complexes.After 3,3',5,5'-tetramethylbenzidine and hydrogen peroxide were injected and catalyzed by the Au@PtNCs,smartphone was used to measure the color of the catalysate for quantitative analysis of target bacteria.Under optimal conditions,this biosensor could detect Salmonella typhimurium quantitatively and automatically in 1 h with a linear detection range of 8.0×10^(1) CFU/mL to 8.0×10^(4) CFU/mL and a detection limit of 62 CFU/mL.The microfluidic biosensor was compact in size,simple to use,and efficient for detection,and might be used for in-field screening of foodborne pathogens to prevent food poisoning.
基金the support from the National Natural Science Foundation of China(20975032,20827006&2009CB421601)
文摘A novel inductance-based sensing technique is presented for remote query measurement in different liquid media including organic solvents and inorganic solutions.The inorganic solutions tested included salt solutions of different concentrations,and the organic solvents detected included 1,4-dioxane and tetrahydrofuran.To extend the application of the sensor,bacterial culture media were also detected,and the growth of Escherichia coli(E.coli)was controlled.The influential factors which may affect the inductance responses were studied in detail.It was found that quantitative relationships exist between the sensor’s inductance response and the physico-chemical parameters of the liquid media.The sensor’s inductance response(L)decreases with the increase of salt concentration(C)and its ionic valence(e)according to a semi-logarithmic equation LgL=-aeC+b,where a and b are constants,which is in accordance with the theoretically deduced equation.The inductance variation rate(ΔK)increases directly with the temperature(T):ΔK=a′T+b′.As for organic solutions,the sensor’s inductance was found to increase with the increasing permittivity of the organic solution.The wireless sensor we designed is simple and easy to manipulate.It has the potential for remote determination of not only chemical substances but also microbiological species such as bacteria.Using the newly developed inductance-based sensor,the pathogenic E.coli was monitored with a limit of detection of 10 cells/mL and a linear semi-logarithmic range of 1.0×101 to 2.5×109 cells/mL.
基金from the National Key Research and Development Program of China(no.2017YFA0505200)the National Natural Science Foundation of China Grant(nos.21625201,21961142010,21661140001,91853202,and 21521003)+1 种基金the Beijing Outstanding Young Scientist Program(no.BJJWZYJH01201910001001)a special research grant for early drug discovery from Roche Pharma Research&Early Development is gratefully acknowledged.
文摘The rise of resistance to all known antibiotics is a global crisis.In addition to novel treatment options,there is an urgent need to develop rapid,specific,sensitive,and reliable diagnostic methods to detect pathogenic bacteria in clinical samples and reduce the overuse and misuse antibiotics.Pseudopaline,a metallophore produced by the human pathogen Pseudomonas aeruginosa,transports divalent metal ions via a dedicated active transport system,making it an ideal carrier for a second functional moiety.
基金This work was supported in part by award#1740961 from the National Science Foundation.
文摘Impedance measurements using graphite electrodes were used to detect the increase in culture medium conductivity due to bacteria growth in real time along with simultaneous voltammetric monitoring of pyocyanin concentration.Electrochemical methods were compared to conventional continuous monitoring of bacterial cultures using turbidity measurement at an optical density of 600 nm(OD600).A practical osmotic system was further designed for concentrating bacterial cultures during growth to enable earlier detection using the electrochemical methods.Bacterial cultures,starting from an initial culture density of 1×10^(8) cells/mL,were grown inside a sealed cellulose ester dialysis membrane,while polyethylene glycol in LB medium was used as the draw solution outside the membrane to gradually concentrate the growing cultures.0.7-mm-diameter graphite for mechanical pencils was utilized as working and counter electrodes with a platinum wire reference electrode for electrochemical measurements with and without the osmotic system.In the absence of forward osmosis,impedance meas-urements detected culture growth~1 h faster than conventional OD600.Integrating osmosis showed a twofold decrease in the time to detect pyocyanin production as an indicator for bacterial growth.For impedance monitoring,removal of water by osmosis was conflated with the impedance decrease due to cell growth;however,the results show a promising ability to detect bacteria growth via an observed shift in osmotic impedance profile when bacteria are present in a sample.By monitoring the deviation in the impedance profile,a threefold improvement in detection time was achieved when compared to conventional OD600 measurements.
基金funded by Engineering and Physical Sciences Research Council(EPSRC,United Kingdom)Interdisciplinary Research Collaboration,Grant Nos.EP/K03197X/1 and EP/R005257/1funded by a Royal Society,Grant No.RGS\R1\201163+1 种基金funded via the BBSRC EastBIO doctoral training program,grant BB/M010996/1funded by a Newton-Bhabha International Fellowship from The Royal Society,UK and The Science and Engineering Research Board,India,Grant No.NIF/R1/192688.
文摘Bacterial resistance,primarily stemming from misdiagnosis,misuse,and overuse of antibacterial medications in humans and animals,is a pressing issue.To address this,we focused on developing a fluorescent probe for the detection of bacteria,with a unique feature--an exceptionally long fluorescence lifetime,to overcome autofluorescence limitations in biological samples.The polymyxin-based probe(ADOTA-PMX)selectively targets Gram-negative bacteria and used the red-emitting fluorophore azadioxatriangulenium(with a reported fluorescence lifetime of 19.5 ns).Evaluation of ADOTA-PMX’s bacterial labeling efficacy revealed strong specificity for Gram-negative bacteria,and full spectral fluorescence lifetime imaging microscopy demonstrated the potential of ADOTA-PMX for bacterial imaging applications.The probe exhibited a lifetime of 4.5 ns when bound to bacteria,possibly indicating interactions with the bacterial outer membrane.Furthermore,the fluorescence lifetime measurements of ADOTA-PMX labeled bacteria could be performed using a benchtop fluorimeter without the need of sophisticated microscopes.This study represents the first targeted probe for fluorescence lifetime imaging,offering sensitivity for detecting Gram-negative bacteria and enabling multiplexing via fluorescence lifetime imaging.
