A simple method to prepare of DNA template suitable for PCR amplification from filamentous fungi will be valuable for improving experimental efficiency.Here,a method was developed which just needed ultrasonic treatmen...A simple method to prepare of DNA template suitable for PCR amplification from filamentous fungi will be valuable for improving experimental efficiency.Here,a method was developed which just needed ultrasonic treatment of the mycelium at usual condition,and the produced solution could directly be used as DNA template for internal transcribed spacer(ITS)amplification successfully.The PCR could be improved by additional treatment of 60℃water baths,but was not centrifugation.When the template amount was 0.5-2μL and the ultrasonic time was 7-11 min,there was no distinctly influences on PCR.The method was commonly used for M.purpureus,I.cicadae,Lentinula sp.,Flammul sp.and Dictyophora sp.etc.to detect target sequences of ITS,hygromycin resistance gene(Hyg),CRISPR-associated protein 9(Cas9),Citrinin gene C(CtnC),Citrinin gene D(CtnD),large subunit rRNA gene(NL),and so on.The method could provide a simple,rapid,safe and economic approach to prepare the DNA template for large-scale PCR of the special filamentous fungi materials.展开更多
Rapid advancements in forensic DNA technology has resulted in its increasing use to resolve crime cases, particularly in the detection of low-level DNA traces. This has been made possible by the increasing sensitivity...Rapid advancements in forensic DNA technology has resulted in its increasing use to resolve crime cases, particularly in the detection of low-level DNA traces. This has been made possible by the increasing sensitivity of STR typing kits. Low-template DNA analysis requires careful consideration of the derived stochastic variations that lead to heterozygote imbalance, allele drop-out and increased detection of background contamination. The relevance of the evidence and the probative value of the DNA profile are important issues in the evaluation of forensic evidence.展开更多
We have developed a simple, productive, and ettectlve poly(cllmetnysltoxane) rranu fer method to fabricate highly conductive Pd nanowires following DNA scaffolds on various substrates, based on ethanolreduction at l...We have developed a simple, productive, and ettectlve poly(cllmetnysltoxane) rranu fer method to fabricate highly conductive Pd nanowires following DNA scaffolds on various substrates, based on ethanolreduction at low temperature. Pd nanoparticles were selectively deposited and confined onto the DNA templates on a PDMS sheet to form Pd nanowires and then the nanowires were transferred to other various substrates with a low occurrence of par asitic nanoparticles. The structure, morphology and the conductance of Pd nanowires were characterized with transmission electron microscopy, field emission scanning electron mi croscopy, and electrical transport measurement, respectively. Moreover, the growth process of the Pd nanowires was investigated by varying the incubation time and reaction temper ature. The present strategy provides a new method to fabricate extremely dense, highly conductive, and well aligned Pd nanowires on various substrates, which make it promising for building nanosensors and nanoelectronic devices.展开更多
DNA-based logic gates promote the development of molecular computing and show enormous potential in the fields of nanotechnology and biotechnology. Dumbbell oligonucleotides(DNA) with poly-thymine(poly-T) loops and a ...DNA-based logic gates promote the development of molecular computing and show enormous potential in the fields of nanotechnology and biotechnology. Dumbbell oligonucleotides(DNA) with poly-thymine(poly-T) loops and a nicked random double strand have been demonstrated to be an efficient template for the formation of fluorescent copper nanoclusters(Cu NCs) in our previous work. Herein, a new platform technology is presented with which to construct molecular logic gates by employing Cu NCs probe as a basic output generator, coupling of functional nucleases as the inputs. Two dumbbell DNAs are used with the difference in stem length(8 bp and 16 bp, respectively). The degradation of DNA templates can be tuned by various nucleic acid enzymes, single-stranded nuclease(S1), double-stranded specific nuclease(DSN), E. coli DNA ligase, exonucleases Ⅰ and Ⅲ. Briefly, S1 can digest both DNA templates, while the cleavage ability of DSN will be resistant by the short stem of SS-DNA(short-stem DNA). Exonuclease Ⅰ and Ⅲ can degrade these two nicked DNA templates, which are inhibited due to the ligation of E. coli DNA ligase. With this novel strategy, a set of logic gates is successfully constructed at the molecular level,including “YES”, “PASS 0”, “OR”, “INHIBIT”, which take the advantages of no label, easy operation, fast speed, high efficiency and low cost. Furthermore, S1 nuclease, as the biomarker of numerous carcinogens,is selectively detected in the range of 0.05–50 U/m L with the detection limit of 0.005 U/m L(1×10^(−6)U)based on this platform.展开更多
The polymerase chain reaction is one of the most useful technical ad- vance and inventions in modern molecular biology. Developed in 1983 by Kary Mullis, PCR is now a common and indispensable technique used in medical...The polymerase chain reaction is one of the most useful technical ad- vance and inventions in modern molecular biology. Developed in 1983 by Kary Mullis, PCR is now a common and indispensable technique used in medical and bi- ology research labs for a variety of applications. A large number of articles relat- ed to PCR are available on the internet and other places. People know well about the basic principle and are very familiar with the procedures of the PCR. But, some details were neglected on the numbers of the target sequence and other DNA strands number after 30 to 35 cycles of the PCR. In most papers, the number of newly synthesized DNA strands including target DNA and non target DNA is am- biguous and even wrong. In this paper, highlights were given to the theoretical number of target DNA number in details and the exact number of the target DNA number can be concluded by analysis.展开更多
Due to recent improvements in forensic DNA testing kit sensitivity,there has been an increased demand in the criminal justice community to revisit past convictions or cold cases.Some of these cases have little biologi...Due to recent improvements in forensic DNA testing kit sensitivity,there has been an increased demand in the criminal justice community to revisit past convictions or cold cases.Some of these cases have little biological evidence other than touch DNA in the form of archived latent fingerprint lift cards.In this study,a previously developed optimised workflow for this sample type was tested on aged fingerprints to determine if improved short tandem repeat(STR)profiles could be obtained.Two-year-old samples processed with the optimised workflow produced an average of approximately five more STR alleles per profile over the traditional method.The optimised workflow also produced detectable alleles in samples aged out to 28 years.Of the methods tested,the optimised workflow resulted in the most informative profiles from evidence samples more representative of the forensic need.This workflow is recommended for use with archived latent fingerprint samples,regardless of the archival time.展开更多
基金Supported by the National Natural Science Foundation of China(81960692)the Science and Technology Support Program of Guizhou Province(2019-2776)。
文摘A simple method to prepare of DNA template suitable for PCR amplification from filamentous fungi will be valuable for improving experimental efficiency.Here,a method was developed which just needed ultrasonic treatment of the mycelium at usual condition,and the produced solution could directly be used as DNA template for internal transcribed spacer(ITS)amplification successfully.The PCR could be improved by additional treatment of 60℃water baths,but was not centrifugation.When the template amount was 0.5-2μL and the ultrasonic time was 7-11 min,there was no distinctly influences on PCR.The method was commonly used for M.purpureus,I.cicadae,Lentinula sp.,Flammul sp.and Dictyophora sp.etc.to detect target sequences of ITS,hygromycin resistance gene(Hyg),CRISPR-associated protein 9(Cas9),Citrinin gene C(CtnC),Citrinin gene D(CtnD),large subunit rRNA gene(NL),and so on.The method could provide a simple,rapid,safe and economic approach to prepare the DNA template for large-scale PCR of the special filamentous fungi materials.
文摘Rapid advancements in forensic DNA technology has resulted in its increasing use to resolve crime cases, particularly in the detection of low-level DNA traces. This has been made possible by the increasing sensitivity of STR typing kits. Low-template DNA analysis requires careful consideration of the derived stochastic variations that lead to heterozygote imbalance, allele drop-out and increased detection of background contamination. The relevance of the evidence and the probative value of the DNA profile are important issues in the evaluation of forensic evidence.
文摘We have developed a simple, productive, and ettectlve poly(cllmetnysltoxane) rranu fer method to fabricate highly conductive Pd nanowires following DNA scaffolds on various substrates, based on ethanolreduction at low temperature. Pd nanoparticles were selectively deposited and confined onto the DNA templates on a PDMS sheet to form Pd nanowires and then the nanowires were transferred to other various substrates with a low occurrence of par asitic nanoparticles. The structure, morphology and the conductance of Pd nanowires were characterized with transmission electron microscopy, field emission scanning electron mi croscopy, and electrical transport measurement, respectively. Moreover, the growth process of the Pd nanowires was investigated by varying the incubation time and reaction temper ature. The present strategy provides a new method to fabricate extremely dense, highly conductive, and well aligned Pd nanowires on various substrates, which make it promising for building nanosensors and nanoelectronic devices.
基金the projects of Innovative research team of high-level local universities in Shanghai and a key laboratory program of the Education Commission of Shanghai Municipality (No. ZDSYS14005)Program for high-level local universities in Shanghai (No. IDF301027/022)+1 种基金Shanghai Agriculture Science and Technology Support Project (No. 21N31900500)the National Natural Science Foundation of China (No. 21505023)
文摘DNA-based logic gates promote the development of molecular computing and show enormous potential in the fields of nanotechnology and biotechnology. Dumbbell oligonucleotides(DNA) with poly-thymine(poly-T) loops and a nicked random double strand have been demonstrated to be an efficient template for the formation of fluorescent copper nanoclusters(Cu NCs) in our previous work. Herein, a new platform technology is presented with which to construct molecular logic gates by employing Cu NCs probe as a basic output generator, coupling of functional nucleases as the inputs. Two dumbbell DNAs are used with the difference in stem length(8 bp and 16 bp, respectively). The degradation of DNA templates can be tuned by various nucleic acid enzymes, single-stranded nuclease(S1), double-stranded specific nuclease(DSN), E. coli DNA ligase, exonucleases Ⅰ and Ⅲ. Briefly, S1 can digest both DNA templates, while the cleavage ability of DSN will be resistant by the short stem of SS-DNA(short-stem DNA). Exonuclease Ⅰ and Ⅲ can degrade these two nicked DNA templates, which are inhibited due to the ligation of E. coli DNA ligase. With this novel strategy, a set of logic gates is successfully constructed at the molecular level,including “YES”, “PASS 0”, “OR”, “INHIBIT”, which take the advantages of no label, easy operation, fast speed, high efficiency and low cost. Furthermore, S1 nuclease, as the biomarker of numerous carcinogens,is selectively detected in the range of 0.05–50 U/m L with the detection limit of 0.005 U/m L(1×10^(−6)U)based on this platform.
文摘The polymerase chain reaction is one of the most useful technical ad- vance and inventions in modern molecular biology. Developed in 1983 by Kary Mullis, PCR is now a common and indispensable technique used in medical and bi- ology research labs for a variety of applications. A large number of articles relat- ed to PCR are available on the internet and other places. People know well about the basic principle and are very familiar with the procedures of the PCR. But, some details were neglected on the numbers of the target sequence and other DNA strands number after 30 to 35 cycles of the PCR. In most papers, the number of newly synthesized DNA strands including target DNA and non target DNA is am- biguous and even wrong. In this paper, highlights were given to the theoretical number of target DNA number in details and the exact number of the target DNA number can be concluded by analysis.
基金This work was supported by the Department of Forensic Science of Virgina Commonwealth University and National Institute of Justice(NIJ)Award 2014-DNBX-K013.
文摘Due to recent improvements in forensic DNA testing kit sensitivity,there has been an increased demand in the criminal justice community to revisit past convictions or cold cases.Some of these cases have little biological evidence other than touch DNA in the form of archived latent fingerprint lift cards.In this study,a previously developed optimised workflow for this sample type was tested on aged fingerprints to determine if improved short tandem repeat(STR)profiles could be obtained.Two-year-old samples processed with the optimised workflow produced an average of approximately five more STR alleles per profile over the traditional method.The optimised workflow also produced detectable alleles in samples aged out to 28 years.Of the methods tested,the optimised workflow resulted in the most informative profiles from evidence samples more representative of the forensic need.This workflow is recommended for use with archived latent fingerprint samples,regardless of the archival time.