Objective To establish a sensitive,simple and rapid detection method for African swine fever virus(ASFV)B646L gene.Methods A recombinase-aided amplification-lateral flow dipstick(RAA-LFD)assay was developed in this st...Objective To establish a sensitive,simple and rapid detection method for African swine fever virus(ASFV)B646L gene.Methods A recombinase-aided amplification-lateral flow dipstick(RAA-LFD)assay was developed in this study.Recombinase-aided amplification(RAA)is used to amplify template DNA,and lateral flow dipstick(LFD)is used to interpret the results after the amplification is completed.The lower limits of detection and specificity of the RAA assay were verified using recombinant plasmid and pathogenic nucleic acid.In addition,30 clinical samples were tested to evaluate the performance of the RAA assay.Results The RAA-LFD assay was completed within 15 min at 37°C,including 10 min for nucleic acid amplification and 5 minutes for LFD reading results.The detection limit of this assay was found to be 200 copies per reaction.And there was no cross-reactivity with other swine viruses.Conclusion A highly sensitive,specific,and simple RAA-LFD method was developed for the rapid detection of the ASFV.展开更多
Objective Recombinase-aided polymerase chain reaction(RAP)is a sensitive,single-tube,two-stage nucleic acid amplification method.This study aimed to develop an assay that can be used for the early diagnosis of three t...Objective Recombinase-aided polymerase chain reaction(RAP)is a sensitive,single-tube,two-stage nucleic acid amplification method.This study aimed to develop an assay that can be used for the early diagnosis of three types of bacteremia caused by Staphylococcus aureus(SA),Pseudomonas aeruginosa(PA),and Acinetobacter baumannii(AB)in the bloodstream based on recombinant human mannanbinding lectin protein(M1 protein)-conjugated magnetic bead(M1 bead)enrichment of pathogens combined with RAP.Methods Recombinant plasmids were used to evaluate the assay sensitivity.Common blood influenza bacteria were used for the specific detection.Simulated and clinical plasma samples were enriched with M1 beads and then subjected to multiple recombinase-aided PCR(M-RAP)and quantitative PCR(qPCR)assays.Kappa analysis was used to evaluate the consistency between the two assays.Results The M-RAP method had sensitivity rates of 1,10,and 1 copies/μL for the detection of SA,PA,and AB plasmids,respectively,without cross-reaction to other bacterial species.The M-RAP assay obtained results for<10 CFU/mL pathogens in the blood within 4 h,with higher sensitivity than qPCR.M-RAP and qPCR for SA,PA,and AB yielded Kappa values of 0.839,0.815,and 0.856,respectively(P<0.05).Conclusion An M-RAP assay for SA,PA,and AB in blood samples utilizing M1 bead enrichment has been developed and can be potentially used for the early detection of bacteremia.展开更多
BACKGROUND Malignant tumors are one of the leading causes of death worldwide,imposing a substantial economic and social burden.Early detection is the key to improving cure rates and reducing mortality rates,which requ...BACKGROUND Malignant tumors are one of the leading causes of death worldwide,imposing a substantial economic and social burden.Early detection is the key to improving cure rates and reducing mortality rates,which requires the development of sensitive early detection technologies.Signal amplification techniques play a crucial role in aptamer-based early detection of tumors and are increasingly garnering attention from researchers.AIM To investigate the current research status,developmental trajectories,and hotspots in signal amplification for aptamer-based tumor detection through bibliometric analysis.METHODS English publications pertaining to signal amplification in aptamer-based tumor detection were retrieved from the Web of Science Core Collection database.VOSviewer and CiteSpace software were employed to analyze various information within this field,including countries,institutions,authors,co-cited authors,journals,co-cited journals,cited references,and keywords.RESULTS A total of 757 publications were included in this study.China accounted for 85.47%of all publications,with Nanjing University(China)emerging as the institution with the highest publication output.The most influential authors and journals were Hasanzadeh M.from Iran and"Biosensors and Bioelectronics",respectively.Exosomes and carcinoembryonic antigen(CEA)stood out as the most researched tumor-related molecules.Currently,the predominant signal amplification technique,nanomaterial,and signal transduction method were identified as hybridization chain reactions,gold nanoparticles,and electrochemical methods,respectively.Over the past 3 years,exosomes,CEA,electrochemical biosensors,and nanosheets have emerged as research hotspots,exhibiting a robust burst of intensity.CONCLUSION This study is the first bibliometric analysis of literature on signal amplification in aptamer-based tumor detection and elucidates the current status,hotspots,and prospective research directions within this realm.Additionally,it provides an important reference for researchers.展开更多
The integrity of the chromosomes for two WIL2-derived lymphoblastoid cell lines (TK6 and WTK1) in the presence and absence of ionizing radiation was analyzed by Multiplex Ligation-Dependent Probe Amplification (MLPA)....The integrity of the chromosomes for two WIL2-derived lymphoblastoid cell lines (TK6 and WTK1) in the presence and absence of ionizing radiation was analyzed by Multiplex Ligation-Dependent Probe Amplification (MLPA). The TK6 cell line has the native p53 tumor-suppressor gene, whereas WTK1 cells contain a p53 mutation. Each cell line was isolated pre- and post-irradiation (2 and 3 Gy) and analyzed by MLPA. The impact of irradiation on these two cell lines was investigated using probes that target specific regions on chromosomes associated with subtelomeric regions. Results indicate that WTK1 and TK6 are impacted differently after irradiation, and that each cell line presents its own unique MLPA profile. The most notable differences are the appearance of a number of probes in the post-irradiated MLPA profile that are not present in the controls, and two unique probe signals only seen in WTK1 cells. These results build on our previous studies that indicate how different human cell lines can be affected by radiation in significantly different ways depending on the presence or absence of wild type p53.展开更多
Rice false smut,caused by Ustilaginoidea virens,is a devastating disease that greatly reduces rice yield and quality.However,controlling rice false smut disease is challenging due to the unique infection mode of U.vir...Rice false smut,caused by Ustilaginoidea virens,is a devastating disease that greatly reduces rice yield and quality.However,controlling rice false smut disease is challenging due to the unique infection mode of U.virens.Therefore,there is a need for early diagnosis and monitoring techniques to prevent the spread of this disease.Lateral flow strip-based recombinase polymerase amplification(LF-RPA)overcomes the limitations of current U.virens detection technologies,which are time-consuming,require delicate equipment,and have a high false-positive rate.In this study,we used a comparative genomics approach to identify Uv_3611,a specific gene of U.virens,as the target for the LF-RPA assay.The designed primers and probe efffectively detected the genomic DNA(gDNA)of U.virens and demonstrated no cross-reactivity with related pathogens.Under optimal conditions,the LF-RPA assay demonstrated a sensitivity of 10 pg of U.virens gDNA.Additionally,by incorporating a simplified PEG-NaOH method for plant DNA extraction,the LF-RPA assay enabled the detection of U.virens in rice spikelets within 30 min,without the need for specialized equipment.Furthermore,the LF-RPA assay successfully detected U.virens in naturally infected rice and seed samples in the field.Therefore,the LF-RPA assay is sensitive,efficient,and convenient,and could be developed as a kit for monitoring rice false smut disease in the field.展开更多
Blasting operations,which are crucial to open-pit mine production due to their simplicity and efficiency,require precise control through accurate vibration velocity calculations.The conventional Sadowski formula mainl...Blasting operations,which are crucial to open-pit mine production due to their simplicity and efficiency,require precise control through accurate vibration velocity calculations.The conventional Sadowski formula mainly focuses on blast center distance but neglects the amplification effect of blasting vibration waves by terraced terrain,from which the calculated blasting vibration velocities are smaller than the actual values,affecting the safety of the project.To address this issue,our model introduces the influences of slope and time into Sadowski formula to measure safety through blast vibration displacement.In the northern section of the open-pit quartz mine in Jinchang City,Gansu Province,China,the data of a continuous blasting slope project are referred to.Our findings reveal a noticeable vibration amplification effect during blasting when a multi-stage slope platform undergoes a sudden cross-sectional change near the upper overhanging surface.The amplification vibration coefficient increases with height,while vibration waves within rocks decrease from bottom to top.Conversely,platforms without distinct crosssectional changes exhibit no pronounced amplification during blasting.In addition,the vibration intensity decreases with distance as the rock height difference change propagates.The results obtained by the proposed blast vibration displacement equation incorporating slope shape influence closely agree with real-world scenarios.According to Pearson correlation coefficient(PPMCC)analysis,the average accuracy rate of our model is 88.84%,which exceeds the conventional Sadowski formula(46.92%).展开更多
BACKGROUND Colorectal cancer(CRC)is the third most common cancer and the second most common cause of cancer-related mortality worldwide.Mesenchymal-epithelial transition factor(MET)gene participates in multiple tumor ...BACKGROUND Colorectal cancer(CRC)is the third most common cancer and the second most common cause of cancer-related mortality worldwide.Mesenchymal-epithelial transition factor(MET)gene participates in multiple tumor biology and shows clinical potential for pharmacological manipulation in tumor treatment.MET amplification has been reported in CRC,but data are very limited.Investigating pathological values of MET in CRC may provide new therapeutic and genetic screening options in future clinical practice.AIM To determine the pathological significance of MET amplification in CRC and to propose a feasible screening strategy.METHODS A number of 205 newly diagnosed CRC patients undergoing surgical resection without any preoperative therapy at Shenzhen Cancer Hospital of Chinese Academy of Medical Sciences were recruited.All patients were without RAS/RAF mutation or microsatellite instability-high.MET amplification and c-MET protein expression were analyzed using fluorescence in situ hybridization(FISH)and immunohistochemistry(IHC),respectively.Correlations between MET aberration and pathological features were detected using the chi-squared test.Progression free survival(PFS)during the two-year follow-up was detected using the Kaplan-Meier method and log rank test.The results of MET FISH and IHC were com pared using one-way ANOVA.RESULTS Polysomy-induced MET amplification was observed in 14.4%of cases,and focal MET amplification was not detected.Polysomy-induced MET amplification was associated with a higher frequency of lymph node metastasis(LNM)(P<0.001)and higher tumor budding grade(P=0.02).In the survival analysis,significant difference was detected between patients with amplified-and non-amplified MET in a two-year follow-up after the first diagnosis(P=0.001).C-MET scores of 0,1+,2+,and 3+were observed in 1.4%,24.9%,54.7%,and 19.0%of tumors,respectively.C-MET overexpression correlated with higher frequency of LNM(P=0.002),but no significant difference of PFS was detected between patients with different protein levels.In terms of concordance between MET FISH and IHC results,MET copy number showed no difference in c-MET IHC 0/1+(3.35±0.18),2+(3.29±0.11)and 3+(3.58±0.22)cohorts,and the MET-to-CEP7 ratio showed no difference in three groups(1.09±0.02,1.10±0.01,and 1.09±0.03).CONCLUSION In CRC,focal MET amplification was a rare event.Polysomy-induced MET amplification correlated with adverse pathological characteristics and poor prognosis.IHC was a poor screening tool for MET amplification.展开更多
Grovers algorithm is a category of quantum algorithms that can be applied to many problems through the exploitation of quantum parallelism. The Amplitude Amplification in Grovers algorithm is T = O(N). This paper intr...Grovers algorithm is a category of quantum algorithms that can be applied to many problems through the exploitation of quantum parallelism. The Amplitude Amplification in Grovers algorithm is T = O(N). This paper introduces two new algorithms for Amplitude Amplification in Grovers algorithm with a time complexity of T = O(logN), aiming to improve efficiency in quantum computing. The difference between Grovers algorithm and our first algorithm is that the Amplitude Amplification ratio in Grovers algorithm is an arithmetic series and ours, a geometric one. Because our Amplitude Amplification ratios converge much faster, the time complexity is improved significantly. In our second algorithm, we introduced a new concept, Amplitude Transfer where the marked state is transferred to a new set of qubits such that the new qubit state is an eigenstate of measurable variables. When the new qubit quantum state is measured, with high probability, the correct solution will be obtained.展开更多
This article analyzes and discusses the working principle and problems encountered by various servo amplification devices used in the on-site continuous adjustment system,analyzes and discusses the application of the ...This article analyzes and discusses the working principle and problems encountered by various servo amplification devices used in the on-site continuous adjustment system,analyzes and discusses the application of the servo mechanism,and analyzes the mechanism of the servo device's implementation of the"positioning"func-tion on the control device.Intended to guide the continuous adjustment process in controlling the function/accuracy of actuator equipment and application debugging,ensuring the safe and stable operation of production equipment and facilities.展开更多
Dairy products have become one of the most prevalent daily foods worldwide,but safety concerns are rising.In dairy farming,unscrupulous traders misuse antibiotics to treat some diseases such as mastitis in cows,leadin...Dairy products have become one of the most prevalent daily foods worldwide,but safety concerns are rising.In dairy farming,unscrupulous traders misuse antibiotics to treat some diseases such as mastitis in cows,leading to antibiotic residues in dairy products.Rapid,sensitive,and simple detection methods for antibiotic residues are particularly important for food safety in dairy products.Traditional detection technology can effectively detect antibiotics,but there are defects such as complicated pre-treatment and high cost.Biosensors are widely used in food safety due to fast detection speed,low detection cost,strong anti-interference ability,and suitability for the field application.Nevertheless,these sensors often fail to trigger the signal conversion output due to low target concentration.To cope with this issue,some high-efficiency signal amplification systems can be introduced to improve the detection sensitivity and linear range of biosensors.In this review,we focused on:(i)Sources and toxicity of major antibiotics in animal-derived foods.(ii)Nanomaterial-mediated biosensors for real-time detection of target antibiotics in animal-derived foods.(iii)Signal amplification techniques to increase the sensitivity of biosensors.Finally,future prospects and challenges in this research field are discussed.展开更多
[Objective] The research aimed to design primers that are suitable for detecting H5 and H7 subtypes of avian influenza virus (AIV) ; [Method] DNAStar was used to analyze the homology of the sequences of H5 and H7 su...[Objective] The research aimed to design primers that are suitable for detecting H5 and H7 subtypes of avian influenza virus (AIV) ; [Method] DNAStar was used to analyze the homology of the sequences of H5 and H7 subtypes of AIV accessed in GenBank, and design primers( by Primer Premier 5.0) on high homologous region of these sequences, and then amplified by RT-PCR. [Result] The multiplex RT-PCR amplification, agarose gel electrophoresis and sequencing results showed that the self-designed primers are successful for detecting AIV. [Conclusion] It is feasible to rapidly diagnose AIV through this method.展开更多
[Objective] The aim was to explore the special methods for amplification of large-family genes by using primers with high degeneracy.[Method] By using the primers with high degeneracy,conventional PCR,conventional tou...[Objective] The aim was to explore the special methods for amplification of large-family genes by using primers with high degeneracy.[Method] By using the primers with high degeneracy,conventional PCR,conventional touchdown PCR and the optimized abnormal touchdown PCR were respectively carried out to amplify the genomic DNA of Cyprinus carpio.[Result] Only one evident electrophoretic band and a few Sox genes were obtained by using normal PCR;no obvious electrophoretic band but dispersive product was obtained by normal touchdown PCR;ideal result was obtained by the abnormal touchdown PCR that three evident electrophoretic bands and much more Sox genes were amplified.[Conclusion] The research provided theoretical basis for the optimization and selection of PCR amplification conditions of the large-family genes.展开更多
Objective] This study aimed to develop a reverse transcription loop-medi-ated isothermal amplification (RT-LAMP) method for detecting BVDV. [Method] Since gp48 gene of BVDV is among the most conserved regions, a set...Objective] This study aimed to develop a reverse transcription loop-medi-ated isothermal amplification (RT-LAMP) method for detecting BVDV. [Method] Since gp48 gene of BVDV is among the most conserved regions, a set of four primers was designed to amplify six target sequences at the gp48 gene region for the RT-LAMP assay. The optimization of the RT-LAMP reaction was performed by evaluat-ing reaction temperature and reaction time. [Result] The RT-LAMP aasay was suc-cessful y conducted at 56 ℃ within 40 min under isothermal conditions, and the re-sults could be detected as ladder-like bands using agarose gel electrophoresis. The RT-LAMP assay is highly sensitive and able to detect 3.74 ×100 copies/μl of BVDV RNA, as no cross-reaction was observed with other viruses. [Conclusion] Overal , the newly established RT-LAMP assay indicates the potential application in both clinical diagnosis and field surveil ance of BVDV.展开更多
A reverse-transcription loop-mediated isothermal amplification (RT-LAMP) method was established for the detection of wheat streak mosaic virus (WSMV). Ac-cording to the conservative regions of the genes that encod...A reverse-transcription loop-mediated isothermal amplification (RT-LAMP) method was established for the detection of wheat streak mosaic virus (WSMV). Ac-cording to the conservative regions of the genes that encode the coat protein of WSMV, 2 pairs of primers were designed. Final y, the 1st pair of primers was select-ed through the specificity test. The sensitivity test showed the sensitivity of RT-LAMP method was 10 times higher than that of RT-PCR. In addition, the amplifica-tion of target gene could be judged visual y from the presence of fluorescence (cal-cein) in the final reaction system. The RT-LAMP method, established in this study, was rapid, easy, specific and sensitive. Moreover, it did not require sophisticated equip-ment. The RT-LAMP was suitable for the rapid detection of WSMV.展开更多
It has been reported that endosperm undergoes programmed cell death (PCD) during maize kernel development.Both bz1 (bronze ) and bz2 are anthocyanin biosynthetic genes,and related to development of aleuronic la...It has been reported that endosperm undergoes programmed cell death (PCD) during maize kernel development.Both bz1 (bronze ) and bz2 are anthocyanin biosynthetic genes,and related to development of aleuronic layer of maize seeds.Tyramide signal amplification fluorescence in situ hybridization (TSA FISH) is a novel and high sensitive FISH technique,which is suitable for routine application in plant cytogenetic research.Using this technique,we physically mapped the bz1 gene onto the short arm of chromosome 9 and the long arm of chromosome 1;the percentage distances from centromere to hybridization site were 40.2,75.4 respectively,and the bz2 onto the long arm of chromosome 1 and the short arm of chromosome 5;the percentage distances from centromere to hybridization site were 21.6,15.3 separately.The TSA FISH techniques of small low copy DNA sequences for plants are discussed.展开更多
Objective: Laser capture microdisection has become indispensable to the analysis of the difference of gene expression between human bladder transitional cell and bladder transitional cell carcinoma (BTCC). However,...Objective: Laser capture microdisection has become indispensable to the analysis of the difference of gene expression between human bladder transitional cell and bladder transitional cell carcinoma (BTCC). However, to obtain sufficient RNA from laser-capture microdissected cells is quite difficult. The study was designed to determinc a feasible technical routine to isolate transitional cells from bladder membrane, separate carcinoma cclls from stromal cells and to amplify the RNA isolated from laser-capture microdissected cells. Methods: Bladder transitional cell were obtained from frozen sections of bladder membrane applying LCM, by the same token, BTCC cells from frozen sections of BTCC tissue. Then RNA was extracted and linearly amplified in vitro. The expression levels of β-actin in primary total RNA and amplified RNA were detected using RT-PCR. Results: That RNA integrity was good after LCM was confirmed by control experiment Ⅰ; By control experiment Ⅱ, the correlation between the number of LCM-shooting and RNA quantity undcr arranged conditions was preliminarily confirmed. About 0.5-2.5kb RNA fragments were obtained after RNA amplification and β-actin levels were integral. Conclusion: Laser capture microdissection combined with RNA linear amplification in vitro can be successfully applied to obtain pure objective cells for research. The integrity of the amplified RNA is good and can be employed in further research.展开更多
Background:Nucleic acid amplification enhancers suitable for use in a recombinase-aided amplification(RAA)assay were studied for the first time,and amplification of a long-fragment(509 bp)was initially explored.Method...Background:Nucleic acid amplification enhancers suitable for use in a recombinase-aided amplification(RAA)assay were studied for the first time,and amplification of a long-fragment(509 bp)was initially explored.Methods:Using recombinant plasmids and clinical samples,RAA fluorescence and basic methods were used to evaluate the efficacy.The fluorescence method was evaluated by threshold time and fluorescence value,and the basic method was characterized by 2%agarose gel electrophoresis.Results:Taking a previously established RAA assay for HPV18 as an example,we demonstrated that the addition of 0.2 M,0.4 M,and 0.6 M betaine and 10%pullulan could enhance the RAA.The new RAA assays with betaine and pullulan were named B-RAA and P-RAA,respectively.Using the B-RAA and P-RAA fluorescence methods,the threshold time values could be shortened by 1.72-2.32 minutes and 2.60 minutes,respectively,and the fluorescence values could be enhanced by 8847.25-9094.37 mv and 5250 mv,respectively.Using the basic method,the sensitivity could be increased 10-fold.We successfully amplified a long-fragment of 509 bp using a P-RAA assay with a sensitivity of 102 copies/μL(compared with 103 copies/μL in the RAA assay).Conclusions:Thus,we concluded that betaine and pullulan are effective additives to enhance the sensitivity of RAA assays.展开更多
Maize chlorotic dwarf virus (MCDV) is a quarantine pest as approved by Chinese government. A rapid, sensitive and specific MCDV detection method using reverse transcription-loop-mediated isothermal amplification (R...Maize chlorotic dwarf virus (MCDV) is a quarantine pest as approved by Chinese government. A rapid, sensitive and specific MCDV detection method using reverse transcription-loop-mediated isothermal amplification (RT-LAMP) was estab- lished in this study. Based on the sequence of MCDV coat protein coding gene, specific primers were designed and similar sensitivities were observed between RT- LAMP and RT-PCR, except that RT-LAMP was quicker, and the reaction could be finished within 1 h. In addition, the presence or absence of the fluorescent display in daylight allows naked easy detection of the amplification of MCDV genomic RNA using calcein. The RT-LAMP assay was applied successfully to detect MCDV in maize seeds, and the result by the addition of calcein was consistent with the result detected by the real time turbidimeter.展开更多
Background:Fluorescent recombinase-aided amplification(RAA)assays are increasingly being used in the detection of a variety of pathogens and have the advantages of rapidity and simplicity and similar sensitivity and s...Background:Fluorescent recombinase-aided amplification(RAA)assays are increasingly being used in the detection of a variety of pathogens and have the advantages of rapidity and simplicity and similar sensitivity and specificity,compared with real-time PCR(qPCR)assays,but they require a complex probe design.To eliminate the addition of fluorescent probes for RAA,an EvaGreen dye-based recombinase-aided amplification(EvaGreen-RAA)assay using self-avoiding molecular recognition system(SAMRS)primers was developed.Methods:The SAMRS primers effectively avoided the production of primer dimers,thus improving the detection sensitivity,while EvaGreen dye was used to quantitatively measure the amplified products in real time.Using Staphy-lococcus aureus(SA)and Listeria monocytogenes(LM)as examples,EvaGreen-RAA with SAMRS primers was developed.As a reference and comparison,a traditional fluorescence probe RAA method and a RAA with SAMRS primers(SAMRS-RAA)for detecting SA and LM were also investigated.Serial di-lutions of recombinant plasmids were used to evaluate the sensitivity of the assays.Unenriched and enriched simulated milk samples were used to eval-uate the limits of detection(LOD)of these methods.Using high-resolution melting(HRM)was used to explore the sensitivity of the dual EvaGreen-RAA assay.Results:The sensitivity of the fluorescent RAA method for detecting SA and LM was 10 copies/μL using plasmids and the sensitivity of the SAMRS-RAA and EvaGreen-RAA for detecting SA and LM plasmids was 1 copies/μL.The LOD values of the EvaGreen-RAA for SA and LM in unenriched simulated milk samples were 100 and 50 CFU/mL,respectively,and the LOD value for both SA and LM using enriched simulated milk samples was 10 CFU/mL.EvaGreen-RAA had linear amplification in real time in the range of 1-10^(5)copies/μL of the plasmids of SA and LM.The sensitivity of the dual EvaGreen-RAA assay for SA and LM was estimated to be 10^(2)CFU/mL.Conclusion:A real-time quantitative EvaGreen-RAA method for detecting SA and LM was developed,which eliminates the need to design complex RAA probes.This dye-based RAA with SARMS primers provides a new strategy for simplifying fluorescence probe RAA and allowing the detection of multiple pathogens,which has many potential applications.展开更多
Polymorphic microsatellites are among the versatile genetic markers in molecular ecology studies. In contrast to de novo isolation of microsatellites from target species, cross-species amplification is a costeffective...Polymorphic microsatellites are among the versatile genetic markers in molecular ecology studies. In contrast to de novo isolation of microsatellites from target species, cross-species amplification is a costeffective approach for a fast development of microsatellite markers from closely related taxa. In our study, we crossamplified a panel of polymorphic microsatellite markers for the Blue Eared Pheasant (Crossoptilon auritum), a species endemic to China of considerable conservation concern. We obtained 11 polymorphic microsatellite markers selected from 112 candidate loci, originally isolated from other Galliforme species. This panel of makers has shown moderate to high levels of polymorphism and include a Z-chromosomal linkage locus. We carried out preliminary analyses of parentage among captive individuals with a known pedigree using this new panel of microsatellites. Our results suggest that the high utility of these markers may be powerful tools for studies in conservation genetics of eared-pheasants and other endangered Galliforme species.展开更多
基金supported by National Key R&D Program of China[2017YFC200503]National Natural Science Foundation of China[No.42077399].
文摘Objective To establish a sensitive,simple and rapid detection method for African swine fever virus(ASFV)B646L gene.Methods A recombinase-aided amplification-lateral flow dipstick(RAA-LFD)assay was developed in this study.Recombinase-aided amplification(RAA)is used to amplify template DNA,and lateral flow dipstick(LFD)is used to interpret the results after the amplification is completed.The lower limits of detection and specificity of the RAA assay were verified using recombinant plasmid and pathogenic nucleic acid.In addition,30 clinical samples were tested to evaluate the performance of the RAA assay.Results The RAA-LFD assay was completed within 15 min at 37°C,including 10 min for nucleic acid amplification and 5 minutes for LFD reading results.The detection limit of this assay was found to be 200 copies per reaction.And there was no cross-reactivity with other swine viruses.Conclusion A highly sensitive,specific,and simple RAA-LFD method was developed for the rapid detection of the ASFV.
基金funded by the National Key R&D Program of China[2021YFC2301102]National Natural Science Foundation of China[82202593]Key R&D Program of Hebei Province[223777100D].
文摘Objective Recombinase-aided polymerase chain reaction(RAP)is a sensitive,single-tube,two-stage nucleic acid amplification method.This study aimed to develop an assay that can be used for the early diagnosis of three types of bacteremia caused by Staphylococcus aureus(SA),Pseudomonas aeruginosa(PA),and Acinetobacter baumannii(AB)in the bloodstream based on recombinant human mannanbinding lectin protein(M1 protein)-conjugated magnetic bead(M1 bead)enrichment of pathogens combined with RAP.Methods Recombinant plasmids were used to evaluate the assay sensitivity.Common blood influenza bacteria were used for the specific detection.Simulated and clinical plasma samples were enriched with M1 beads and then subjected to multiple recombinase-aided PCR(M-RAP)and quantitative PCR(qPCR)assays.Kappa analysis was used to evaluate the consistency between the two assays.Results The M-RAP method had sensitivity rates of 1,10,and 1 copies/μL for the detection of SA,PA,and AB plasmids,respectively,without cross-reaction to other bacterial species.The M-RAP assay obtained results for<10 CFU/mL pathogens in the blood within 4 h,with higher sensitivity than qPCR.M-RAP and qPCR for SA,PA,and AB yielded Kappa values of 0.839,0.815,and 0.856,respectively(P<0.05).Conclusion An M-RAP assay for SA,PA,and AB in blood samples utilizing M1 bead enrichment has been developed and can be potentially used for the early detection of bacteremia.
基金National Natural Science Foundation of China,No.82160494 and No.82160444.
文摘BACKGROUND Malignant tumors are one of the leading causes of death worldwide,imposing a substantial economic and social burden.Early detection is the key to improving cure rates and reducing mortality rates,which requires the development of sensitive early detection technologies.Signal amplification techniques play a crucial role in aptamer-based early detection of tumors and are increasingly garnering attention from researchers.AIM To investigate the current research status,developmental trajectories,and hotspots in signal amplification for aptamer-based tumor detection through bibliometric analysis.METHODS English publications pertaining to signal amplification in aptamer-based tumor detection were retrieved from the Web of Science Core Collection database.VOSviewer and CiteSpace software were employed to analyze various information within this field,including countries,institutions,authors,co-cited authors,journals,co-cited journals,cited references,and keywords.RESULTS A total of 757 publications were included in this study.China accounted for 85.47%of all publications,with Nanjing University(China)emerging as the institution with the highest publication output.The most influential authors and journals were Hasanzadeh M.from Iran and"Biosensors and Bioelectronics",respectively.Exosomes and carcinoembryonic antigen(CEA)stood out as the most researched tumor-related molecules.Currently,the predominant signal amplification technique,nanomaterial,and signal transduction method were identified as hybridization chain reactions,gold nanoparticles,and electrochemical methods,respectively.Over the past 3 years,exosomes,CEA,electrochemical biosensors,and nanosheets have emerged as research hotspots,exhibiting a robust burst of intensity.CONCLUSION This study is the first bibliometric analysis of literature on signal amplification in aptamer-based tumor detection and elucidates the current status,hotspots,and prospective research directions within this realm.Additionally,it provides an important reference for researchers.
文摘The integrity of the chromosomes for two WIL2-derived lymphoblastoid cell lines (TK6 and WTK1) in the presence and absence of ionizing radiation was analyzed by Multiplex Ligation-Dependent Probe Amplification (MLPA). The TK6 cell line has the native p53 tumor-suppressor gene, whereas WTK1 cells contain a p53 mutation. Each cell line was isolated pre- and post-irradiation (2 and 3 Gy) and analyzed by MLPA. The impact of irradiation on these two cell lines was investigated using probes that target specific regions on chromosomes associated with subtelomeric regions. Results indicate that WTK1 and TK6 are impacted differently after irradiation, and that each cell line presents its own unique MLPA profile. The most notable differences are the appearance of a number of probes in the post-irradiated MLPA profile that are not present in the controls, and two unique probe signals only seen in WTK1 cells. These results build on our previous studies that indicate how different human cell lines can be affected by radiation in significantly different ways depending on the presence or absence of wild type p53.
基金supported by grants from the Jiangsu Agricultural Science and Technology Innovation Fund,China(JASTIF)(CX(21)3012)to Haifeng Zhang。
文摘Rice false smut,caused by Ustilaginoidea virens,is a devastating disease that greatly reduces rice yield and quality.However,controlling rice false smut disease is challenging due to the unique infection mode of U.virens.Therefore,there is a need for early diagnosis and monitoring techniques to prevent the spread of this disease.Lateral flow strip-based recombinase polymerase amplification(LF-RPA)overcomes the limitations of current U.virens detection technologies,which are time-consuming,require delicate equipment,and have a high false-positive rate.In this study,we used a comparative genomics approach to identify Uv_3611,a specific gene of U.virens,as the target for the LF-RPA assay.The designed primers and probe efffectively detected the genomic DNA(gDNA)of U.virens and demonstrated no cross-reactivity with related pathogens.Under optimal conditions,the LF-RPA assay demonstrated a sensitivity of 10 pg of U.virens gDNA.Additionally,by incorporating a simplified PEG-NaOH method for plant DNA extraction,the LF-RPA assay enabled the detection of U.virens in rice spikelets within 30 min,without the need for specialized equipment.Furthermore,the LF-RPA assay successfully detected U.virens in naturally infected rice and seed samples in the field.Therefore,the LF-RPA assay is sensitive,efficient,and convenient,and could be developed as a kit for monitoring rice false smut disease in the field.
文摘Blasting operations,which are crucial to open-pit mine production due to their simplicity and efficiency,require precise control through accurate vibration velocity calculations.The conventional Sadowski formula mainly focuses on blast center distance but neglects the amplification effect of blasting vibration waves by terraced terrain,from which the calculated blasting vibration velocities are smaller than the actual values,affecting the safety of the project.To address this issue,our model introduces the influences of slope and time into Sadowski formula to measure safety through blast vibration displacement.In the northern section of the open-pit quartz mine in Jinchang City,Gansu Province,China,the data of a continuous blasting slope project are referred to.Our findings reveal a noticeable vibration amplification effect during blasting when a multi-stage slope platform undergoes a sudden cross-sectional change near the upper overhanging surface.The amplification vibration coefficient increases with height,while vibration waves within rocks decrease from bottom to top.Conversely,platforms without distinct crosssectional changes exhibit no pronounced amplification during blasting.In addition,the vibration intensity decreases with distance as the rock height difference change propagates.The results obtained by the proposed blast vibration displacement equation incorporating slope shape influence closely agree with real-world scenarios.According to Pearson correlation coefficient(PPMCC)analysis,the average accuracy rate of our model is 88.84%,which exceeds the conventional Sadowski formula(46.92%).
基金the National Natural Science Foundation of China,No.82002829.
文摘BACKGROUND Colorectal cancer(CRC)is the third most common cancer and the second most common cause of cancer-related mortality worldwide.Mesenchymal-epithelial transition factor(MET)gene participates in multiple tumor biology and shows clinical potential for pharmacological manipulation in tumor treatment.MET amplification has been reported in CRC,but data are very limited.Investigating pathological values of MET in CRC may provide new therapeutic and genetic screening options in future clinical practice.AIM To determine the pathological significance of MET amplification in CRC and to propose a feasible screening strategy.METHODS A number of 205 newly diagnosed CRC patients undergoing surgical resection without any preoperative therapy at Shenzhen Cancer Hospital of Chinese Academy of Medical Sciences were recruited.All patients were without RAS/RAF mutation or microsatellite instability-high.MET amplification and c-MET protein expression were analyzed using fluorescence in situ hybridization(FISH)and immunohistochemistry(IHC),respectively.Correlations between MET aberration and pathological features were detected using the chi-squared test.Progression free survival(PFS)during the two-year follow-up was detected using the Kaplan-Meier method and log rank test.The results of MET FISH and IHC were com pared using one-way ANOVA.RESULTS Polysomy-induced MET amplification was observed in 14.4%of cases,and focal MET amplification was not detected.Polysomy-induced MET amplification was associated with a higher frequency of lymph node metastasis(LNM)(P<0.001)and higher tumor budding grade(P=0.02).In the survival analysis,significant difference was detected between patients with amplified-and non-amplified MET in a two-year follow-up after the first diagnosis(P=0.001).C-MET scores of 0,1+,2+,and 3+were observed in 1.4%,24.9%,54.7%,and 19.0%of tumors,respectively.C-MET overexpression correlated with higher frequency of LNM(P=0.002),but no significant difference of PFS was detected between patients with different protein levels.In terms of concordance between MET FISH and IHC results,MET copy number showed no difference in c-MET IHC 0/1+(3.35±0.18),2+(3.29±0.11)and 3+(3.58±0.22)cohorts,and the MET-to-CEP7 ratio showed no difference in three groups(1.09±0.02,1.10±0.01,and 1.09±0.03).CONCLUSION In CRC,focal MET amplification was a rare event.Polysomy-induced MET amplification correlated with adverse pathological characteristics and poor prognosis.IHC was a poor screening tool for MET amplification.
文摘Grovers algorithm is a category of quantum algorithms that can be applied to many problems through the exploitation of quantum parallelism. The Amplitude Amplification in Grovers algorithm is T = O(N). This paper introduces two new algorithms for Amplitude Amplification in Grovers algorithm with a time complexity of T = O(logN), aiming to improve efficiency in quantum computing. The difference between Grovers algorithm and our first algorithm is that the Amplitude Amplification ratio in Grovers algorithm is an arithmetic series and ours, a geometric one. Because our Amplitude Amplification ratios converge much faster, the time complexity is improved significantly. In our second algorithm, we introduced a new concept, Amplitude Transfer where the marked state is transferred to a new set of qubits such that the new qubit state is an eigenstate of measurable variables. When the new qubit quantum state is measured, with high probability, the correct solution will be obtained.
文摘This article analyzes and discusses the working principle and problems encountered by various servo amplification devices used in the on-site continuous adjustment system,analyzes and discusses the application of the servo mechanism,and analyzes the mechanism of the servo device's implementation of the"positioning"func-tion on the control device.Intended to guide the continuous adjustment process in controlling the function/accuracy of actuator equipment and application debugging,ensuring the safe and stable operation of production equipment and facilities.
基金We thank the Natural Science Foundation of Hubei Province of China(2023AFB330)the China Postdoctoral Science Foundation(2022M721275)the Hubei Provincial Market Supervision Administration Science and Technology Program Project(Hbscjg-KJ2021002)for financial support.
文摘Dairy products have become one of the most prevalent daily foods worldwide,but safety concerns are rising.In dairy farming,unscrupulous traders misuse antibiotics to treat some diseases such as mastitis in cows,leading to antibiotic residues in dairy products.Rapid,sensitive,and simple detection methods for antibiotic residues are particularly important for food safety in dairy products.Traditional detection technology can effectively detect antibiotics,but there are defects such as complicated pre-treatment and high cost.Biosensors are widely used in food safety due to fast detection speed,low detection cost,strong anti-interference ability,and suitability for the field application.Nevertheless,these sensors often fail to trigger the signal conversion output due to low target concentration.To cope with this issue,some high-efficiency signal amplification systems can be introduced to improve the detection sensitivity and linear range of biosensors.In this review,we focused on:(i)Sources and toxicity of major antibiotics in animal-derived foods.(ii)Nanomaterial-mediated biosensors for real-time detection of target antibiotics in animal-derived foods.(iii)Signal amplification techniques to increase the sensitivity of biosensors.Finally,future prospects and challenges in this research field are discussed.
基金Supported by Important Project of Jinlin Provincial Science and Technology Department(20065020)~~
文摘[Objective] The research aimed to design primers that are suitable for detecting H5 and H7 subtypes of avian influenza virus (AIV) ; [Method] DNAStar was used to analyze the homology of the sequences of H5 and H7 subtypes of AIV accessed in GenBank, and design primers( by Primer Premier 5.0) on high homologous region of these sequences, and then amplified by RT-PCR. [Result] The multiplex RT-PCR amplification, agarose gel electrophoresis and sequencing results showed that the self-designed primers are successful for detecting AIV. [Conclusion] It is feasible to rapidly diagnose AIV through this method.
文摘[Objective] The aim was to explore the special methods for amplification of large-family genes by using primers with high degeneracy.[Method] By using the primers with high degeneracy,conventional PCR,conventional touchdown PCR and the optimized abnormal touchdown PCR were respectively carried out to amplify the genomic DNA of Cyprinus carpio.[Result] Only one evident electrophoretic band and a few Sox genes were obtained by using normal PCR;no obvious electrophoretic band but dispersive product was obtained by normal touchdown PCR;ideal result was obtained by the abnormal touchdown PCR that three evident electrophoretic bands and much more Sox genes were amplified.[Conclusion] The research provided theoretical basis for the optimization and selection of PCR amplification conditions of the large-family genes.
文摘Objective] This study aimed to develop a reverse transcription loop-medi-ated isothermal amplification (RT-LAMP) method for detecting BVDV. [Method] Since gp48 gene of BVDV is among the most conserved regions, a set of four primers was designed to amplify six target sequences at the gp48 gene region for the RT-LAMP assay. The optimization of the RT-LAMP reaction was performed by evaluat-ing reaction temperature and reaction time. [Result] The RT-LAMP aasay was suc-cessful y conducted at 56 ℃ within 40 min under isothermal conditions, and the re-sults could be detected as ladder-like bands using agarose gel electrophoresis. The RT-LAMP assay is highly sensitive and able to detect 3.74 ×100 copies/μl of BVDV RNA, as no cross-reaction was observed with other viruses. [Conclusion] Overal , the newly established RT-LAMP assay indicates the potential application in both clinical diagnosis and field surveil ance of BVDV.
文摘A reverse-transcription loop-mediated isothermal amplification (RT-LAMP) method was established for the detection of wheat streak mosaic virus (WSMV). Ac-cording to the conservative regions of the genes that encode the coat protein of WSMV, 2 pairs of primers were designed. Final y, the 1st pair of primers was select-ed through the specificity test. The sensitivity test showed the sensitivity of RT-LAMP method was 10 times higher than that of RT-PCR. In addition, the amplifica-tion of target gene could be judged visual y from the presence of fluorescence (cal-cein) in the final reaction system. The RT-LAMP method, established in this study, was rapid, easy, specific and sensitive. Moreover, it did not require sophisticated equip-ment. The RT-LAMP was suitable for the rapid detection of WSMV.
文摘It has been reported that endosperm undergoes programmed cell death (PCD) during maize kernel development.Both bz1 (bronze ) and bz2 are anthocyanin biosynthetic genes,and related to development of aleuronic layer of maize seeds.Tyramide signal amplification fluorescence in situ hybridization (TSA FISH) is a novel and high sensitive FISH technique,which is suitable for routine application in plant cytogenetic research.Using this technique,we physically mapped the bz1 gene onto the short arm of chromosome 9 and the long arm of chromosome 1;the percentage distances from centromere to hybridization site were 40.2,75.4 respectively,and the bz2 onto the long arm of chromosome 1 and the short arm of chromosome 5;the percentage distances from centromere to hybridization site were 21.6,15.3 separately.The TSA FISH techniques of small low copy DNA sequences for plants are discussed.
文摘Objective: Laser capture microdisection has become indispensable to the analysis of the difference of gene expression between human bladder transitional cell and bladder transitional cell carcinoma (BTCC). However, to obtain sufficient RNA from laser-capture microdissected cells is quite difficult. The study was designed to determinc a feasible technical routine to isolate transitional cells from bladder membrane, separate carcinoma cclls from stromal cells and to amplify the RNA isolated from laser-capture microdissected cells. Methods: Bladder transitional cell were obtained from frozen sections of bladder membrane applying LCM, by the same token, BTCC cells from frozen sections of BTCC tissue. Then RNA was extracted and linearly amplified in vitro. The expression levels of β-actin in primary total RNA and amplified RNA were detected using RT-PCR. Results: That RNA integrity was good after LCM was confirmed by control experiment Ⅰ; By control experiment Ⅱ, the correlation between the number of LCM-shooting and RNA quantity undcr arranged conditions was preliminarily confirmed. About 0.5-2.5kb RNA fragments were obtained after RNA amplification and β-actin levels were integral. Conclusion: Laser capture microdissection combined with RNA linear amplification in vitro can be successfully applied to obtain pure objective cells for research. The integrity of the amplified RNA is good and can be employed in further research.
基金supported by grants from the Youth Foundation of Academician Hou Yunde[grant number 2019HYDQNJJ03]China Mega-Projects for Infec-tious Disease[grant number 2017ZX10302301-004-002].
文摘Background:Nucleic acid amplification enhancers suitable for use in a recombinase-aided amplification(RAA)assay were studied for the first time,and amplification of a long-fragment(509 bp)was initially explored.Methods:Using recombinant plasmids and clinical samples,RAA fluorescence and basic methods were used to evaluate the efficacy.The fluorescence method was evaluated by threshold time and fluorescence value,and the basic method was characterized by 2%agarose gel electrophoresis.Results:Taking a previously established RAA assay for HPV18 as an example,we demonstrated that the addition of 0.2 M,0.4 M,and 0.6 M betaine and 10%pullulan could enhance the RAA.The new RAA assays with betaine and pullulan were named B-RAA and P-RAA,respectively.Using the B-RAA and P-RAA fluorescence methods,the threshold time values could be shortened by 1.72-2.32 minutes and 2.60 minutes,respectively,and the fluorescence values could be enhanced by 8847.25-9094.37 mv and 5250 mv,respectively.Using the basic method,the sensitivity could be increased 10-fold.We successfully amplified a long-fragment of 509 bp using a P-RAA assay with a sensitivity of 102 copies/μL(compared with 103 copies/μL in the RAA assay).Conclusions:Thus,we concluded that betaine and pullulan are effective additives to enhance the sensitivity of RAA assays.
文摘Maize chlorotic dwarf virus (MCDV) is a quarantine pest as approved by Chinese government. A rapid, sensitive and specific MCDV detection method using reverse transcription-loop-mediated isothermal amplification (RT-LAMP) was estab- lished in this study. Based on the sequence of MCDV coat protein coding gene, specific primers were designed and similar sensitivities were observed between RT- LAMP and RT-PCR, except that RT-LAMP was quicker, and the reaction could be finished within 1 h. In addition, the presence or absence of the fluorescent display in daylight allows naked easy detection of the amplification of MCDV genomic RNA using calcein. The RT-LAMP assay was applied successfully to detect MCDV in maize seeds, and the result by the addition of calcein was consistent with the result detected by the real time turbidimeter.
基金National Key R&D Program of China,Grant/Award Number:2021YFC2301102National Natural Science Foundation of China,Grant/Award Numbers:82202593,U23A20106。
文摘Background:Fluorescent recombinase-aided amplification(RAA)assays are increasingly being used in the detection of a variety of pathogens and have the advantages of rapidity and simplicity and similar sensitivity and specificity,compared with real-time PCR(qPCR)assays,but they require a complex probe design.To eliminate the addition of fluorescent probes for RAA,an EvaGreen dye-based recombinase-aided amplification(EvaGreen-RAA)assay using self-avoiding molecular recognition system(SAMRS)primers was developed.Methods:The SAMRS primers effectively avoided the production of primer dimers,thus improving the detection sensitivity,while EvaGreen dye was used to quantitatively measure the amplified products in real time.Using Staphy-lococcus aureus(SA)and Listeria monocytogenes(LM)as examples,EvaGreen-RAA with SAMRS primers was developed.As a reference and comparison,a traditional fluorescence probe RAA method and a RAA with SAMRS primers(SAMRS-RAA)for detecting SA and LM were also investigated.Serial di-lutions of recombinant plasmids were used to evaluate the sensitivity of the assays.Unenriched and enriched simulated milk samples were used to eval-uate the limits of detection(LOD)of these methods.Using high-resolution melting(HRM)was used to explore the sensitivity of the dual EvaGreen-RAA assay.Results:The sensitivity of the fluorescent RAA method for detecting SA and LM was 10 copies/μL using plasmids and the sensitivity of the SAMRS-RAA and EvaGreen-RAA for detecting SA and LM plasmids was 1 copies/μL.The LOD values of the EvaGreen-RAA for SA and LM in unenriched simulated milk samples were 100 and 50 CFU/mL,respectively,and the LOD value for both SA and LM using enriched simulated milk samples was 10 CFU/mL.EvaGreen-RAA had linear amplification in real time in the range of 1-10^(5)copies/μL of the plasmids of SA and LM.The sensitivity of the dual EvaGreen-RAA assay for SA and LM was estimated to be 10^(2)CFU/mL.Conclusion:A real-time quantitative EvaGreen-RAA method for detecting SA and LM was developed,which eliminates the need to design complex RAA probes.This dye-based RAA with SARMS primers provides a new strategy for simplifying fluorescence probe RAA and allowing the detection of multiple pathogens,which has many potential applications.
基金supported by the National Key Project of the Scientific and Technical Supporting Programs Funded by the Ministry of Science and Technology of China(2012BAC01B06)the National Natural Science Foundation of China (No. 30570234)
文摘Polymorphic microsatellites are among the versatile genetic markers in molecular ecology studies. In contrast to de novo isolation of microsatellites from target species, cross-species amplification is a costeffective approach for a fast development of microsatellite markers from closely related taxa. In our study, we crossamplified a panel of polymorphic microsatellite markers for the Blue Eared Pheasant (Crossoptilon auritum), a species endemic to China of considerable conservation concern. We obtained 11 polymorphic microsatellite markers selected from 112 candidate loci, originally isolated from other Galliforme species. This panel of makers has shown moderate to high levels of polymorphism and include a Z-chromosomal linkage locus. We carried out preliminary analyses of parentage among captive individuals with a known pedigree using this new panel of microsatellites. Our results suggest that the high utility of these markers may be powerful tools for studies in conservation genetics of eared-pheasants and other endangered Galliforme species.