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1.
Front Microbiol ; 15: 1406632, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39091309

RESUMO

Loop-mediated isothermal amplification (LAMP) is a novel method for nucleic acid detection known for its isothermal properties, high efficiency, sensitivity, and specificity. LAMP employs 4 to 6 primers targeting 6 to 8 regions of the desired sequence, allowing for amplification at temperatures between 60 and 65°C and the production of up to 109 copies within a single hour. The product can be monitored by various methods such as turbidimetry, fluorometry, and colorimetry. However, it faces limitations such as the risk of non-specific amplification, challenges in primer design, unsuitability for short gene sequences, and difficulty in multiplexing. Recent advancements in polymerase and primer design have enhanced the speed and convenience of the LAMP reaction. Additionally, integrating LAMP with technologies like rolling circle amplification (RCA), recombinase polymerase amplification (RPA), and CRISPR-Cas systems has enhanced its efficiency. The combination of LAMP with various biosensors has enabled real-time analysis, broadening its application in point-of-care testing (POCT). Microfluidic technology has further facilitated the automation and miniaturization of LAMP assays, allowing for the simultaneous detection of multiple targets and preventing contamination. This review highlights advancements in LAMP, focusing on primer design, polymerase engineering, and its integration with other technologies. Continuous improvements and integration of LAMP with complementary technologies have significantly enhanced its diagnostic capabilities, making it a robust tool for rapid, sensitive, and specific nucleic acid detection with promising implications for healthcare, agriculture, and environmental monitoring.

2.
Polymers (Basel) ; 16(13)2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-39000693

RESUMO

The development of high-filled 3D printing resin necessitates a bonding protocol for dental indirect restorations to achieve optimal bond strength after cementation. This study evaluates shear bond strengths of high-filler 3D printed materials for permanent restorations with various surface treatments. Rodin Sculpture 1.0 (50% lithium disilicate fillers) and 2.0 Ceramic Nanohybrid (>60% zirconia and lithium disilicate fillers) were tested, with Aelite All-Purpose Body composite resin as control. Samples were prepared, post-cured, and sandblasted with alumina (25 µm). Surface roughness was analyzed using an optical profilometer. Two bonding protocols were compared. First, groups were treated with lithium disilicate silane (Porcelain Primer) or zirconia primer (Z-Prime Plus) or left untreated without a bonding agent. Beam-shaped resin cement (DuoLink Universal) specimens were bonded and stored in a 37 °C water bath. Second, additional sets of materials were coated with a bonding agent (All-Bond Universal), either followed by silane application or left untreated. These sets were then similarly stored alongside resin cement specimens. Shear bond tests were performed after 24 h. SEM images were taken after debonding. One-Way ANOVA and post hoc Duncan were performed for the statistical analysis. Rodin 1.0 exhibited increased adhesive failure with silane or zirconia primer coating, but significantly improved bond strengths with bonding agent application. Rodin 2.0 showed consistent bond strengths regardless of bonding agent application, but cohesive failure rates increased with bonding agent and filler coating. In all groups, except for Rodin 1.0 without bonding agent, silane coating increased cohesive failure rate. In conclusion, optimal shear bond strength for high-filler 3D printing materials can be achieved with silane coating and bonding agent application.

3.
Polymers (Basel) ; 16(13)2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-39000764

RESUMO

Untreated polyester films and fibers can be hardly printed or coated, in particular if aqueous inks or lacquers have to be applied. Therefore, an adequate primer layer has to be applied first. A cationic polymer formulation based on poly(dimethylamine-co-epichlorohydrin-co-ethylenediamine) (PDEHED) was used as primer layer for digital printing on polyester fabrics. Because of the exceedingly high requirements on the homogeneity of such layers, hyperspectral imaging was used for qualitative and quantitative monitoring of the distribution of the primer layer on the textiles. Multivariate data analysis methods based on the PLS algorithm were applied for quantification of the NIR reflection spectra using gravimetry as a reference method. Optimization of the calibration method resulted in various models with prediction errors of about 1.2 g/m2. The prediction performance of the models was proven in external validations using independent samples. Moreover, a special ink jet printing technology was tested for application of the aqueous primer formulation itself. Since possible clogging of jet nozzles in the print head might lead to inhomogeneity in the coatings such as missing tracks, the potential of hyperspectral imaging to detect such defects was investigated. It was demonstrated that simulated missing tracks can be clearly detected. Consequently, hyperspectral imaging has been proven to be a powerful analytical tool for in-line monitoring of the quality of printability improvement layers and similar systems.

4.
Mycobiology ; 52(3): 172-182, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38948453

RESUMO

Truffles, belonging to the genus Tuber, are ectomycorrhizal (ECM) fungi that form underground ascocarps and primarily establish symbiosis with oaks and hazels. The cultivation of Tuber spp. involves transplanting inoculated seedlings that have formed ectomycorrhiza with Tuber species, with mulching being effective for truffle cultivation. In this study, we investigated the effects of mulching on the mycelial growth of four Tuber species (T. himalayense, T. koreanum, T. melanosporum, and T. borchii) in the Korean natural environment, highlighting the potential for Korea as a truffle cultivation site. We developed and tested species-specific primers for quantifying the soil mycelial biomass of Tuber spp. by qRT-PCR, determined the superior mulch color for mycelial growth, and identified the Tuber species exhibiting the highest growth rate in the Korean field environment. Our results demonstrated that white mulch significantly enhanced mycelial growth in Tuber species than black mulch, likely owing to its ability to maintain low soil temperatures, control weeds, and improve host plant growth. Among the Tuber species, T. himalayense showed the greatest growth potential in the Korean natural environment. Additionally, a significant and positive correlation was observed between the mycelial biomass of Tuber species and the growth of inoculated seedlings, as measured by the total stem length and the number of leaves, thereby indicating the importance of symbiosis between ECM fungi and host plants. This study provides valuable insights into truffle cultivation in Korea and highlights the potential of using white mulch to promote mycelial growth, thereby contributing essential data for understanding the appropriate environmental conditions for Tuber spp. cultivation in Korea. Further study is needed to assess the long-term impact of mulching and to explore the effectiveness of other mulching materials.

5.
Braz J Microbiol ; 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38987524

RESUMO

The significance of the Southern Ocean (SO) as a sink of atmospheric CO2 and other greenhouse gases is well established. Earlier studies have highlighted the role of microbes in various SO ecosystem processes. However, the diversity and role of actinobacteria in the Indian sector of SO (ISO) water and sediments are unknown. This study aimed to analyze the diversity of actinobacteria in water and sediment samples of SO based on amplicon microbiome analyses. The taxonomic analysis identified a total number of 27 phyla of which Proteobacteria (40.2%), Actinobacteria (13.6%), and Firmicutes (8.7%) were found to be dominant. The comparative study of water and sediment samples revealed the dominance of different actinobacteria in water and sediments. While the order Streptomycetales was dominant in the water samples, Micrococcales was found to be dominant in the sediment samples. The genus level analysis found the presence of eight and seventeen genera in the sediment and water samples, respectively. The genus Streptomyces, Saccharopolyspora, Nocardioides, Sva0996 marine group, and Mycobacterium were seen both in sediment and water samples. Marmoricola, Ilumatobacter, and Glaciihabitans were observed only in sediment samples whereas Rhodococcus, Corynebacterium, Micrococcus, Turicella, Pseudonocardia, Bifidobacterium, Nesterenkonia, Collinsella, Knoellia, Cadidatus, Actinomarina, Libanicoccus and Cutibacterium were noticed exclusively in water samples. Our study also emphasizes the need for further detailed study to understand the links between actinobacterial diversity and their ecological functions in the ISO. The available metabarcoding data paves the way for future research in cultivable forms of novel and rare Actinobacteria for their bioprospecting applications.

6.
Euro Surveill ; 29(28)2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38994600

RESUMO

We investigated a variant of measles virus that encodes three mismatches to the reverse priming site for a widely used diagnostic real-time RT-PCR assay; reduction of sensitivity was hypothesised. We examined performance of the assay in context of the variant using in silico data, synthetic RNA templates and clinical specimens. Sensitivity was reduced observed at low copy numbers for templates encoding the variant sequence. We designed and tested an alternate priming strategy, rescuing the sensitivity of the assay.


Assuntos
Vírus do Sarampo , Sarampo , RNA Viral , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sensibilidade e Especificidade , Humanos , Sarampo/diagnóstico , Sarampo/virologia , Vírus do Sarampo/genética , Vírus do Sarampo/isolamento & purificação , Reação em Cadeia da Polimerase em Tempo Real/métodos , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , RNA Viral/genética
8.
Front Plant Sci ; 15: 1399718, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39045589

RESUMO

The oriental fruit fly, Bactrocera dorsalis (Hendel), is a significant economic and quarantine pest due to its polyphagous nature. The accurate identification of B. dorsalis is challenging at the egg, maggot, and pupal stages, due to lack of distinct morphological characters and its similarity to other fruit flies. Adult identification requires specialized taxonomist. Existing identification methods are laborious, time consuming, and expensive. Rapid and precise identification is crucial for timely management. By analyzing the variations in the mitochondrial cytochrome oxidase-1 gene sequence (Insect barcoding gene), we developed a species-specific primer (SSP), DorFP1/DorRP1, for accurate identification of B. dorsalis. The optimal annealing temperature for the SSP was determined to be 66°C, with no cross-amplification or primer-dimer formation observed. The SSP was validated with B. dorsalis specimens from various locations in northern and eastern India and tested for cross-specificity with six other economically significant fruit fly species in India. The primer specificity was further confirmed by the analysis of critical threshold (Ct) value from a qPCR assay. Sensitivity analysis showed the primer could detect template DNA concentrations as low as 1 pg/µl, though sensitivity decreased at lower concentrations. Sequencing of the SSP-amplified product revealed over >99% similarity with existing B. dorsalis sequences in the NCBI GenBank. The developed SSP reliably identifies B. dorsalis across all developmental stages and sexes. This assay is expected to significantly impact pest identification, phytosanitary measures, and eradication programs for B. dorsalis.

9.
Proc Natl Acad Sci U S A ; 121(29): e2317977121, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-38990941

RESUMO

In a recent characterization of the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) variability present in 30 diagnostic samples from patients of the first COVID-19 pandemic wave, 41 amino acid substitutions were documented in the RNA-dependent RNA polymerase (RdRp) nsp12. Eight substitutions were selected in this work to determine whether they had an impact on the RdRp activity of the SARS-CoV-2 nsp12-nsp8-nsp7 replication complex. Three of these substitutions were found around the polymerase central cavity, in the template entry channel (D499G and M668V), and within the motif B (V560A), and they showed polymerization rates similar to the wild type RdRp. The remaining five mutations (P323L, L372F, L372P, V373A, and L527H) were placed near the nsp12-nsp8F contact surface; residues L372, V373, and L527 participated in a large hydrophobic cluster involving contacts between two helices in the nsp12 fingers and the long α-helix of nsp8F. The presence of any of these five amino acid substitutions resulted in important alterations in the RNA polymerization activity. Comparative primer elongation assays showed different behavior depending on the hydrophobicity of their side chains. The substitution of L by the bulkier F side chain at position 372 slightly promoted RdRp activity. However, this activity was dramatically reduced with the L372P, and L527H mutations, and to a lesser extent with V373A, all of which weaken the hydrophobic interactions within the cluster. Additional mutations, specifically designed to disrupt the nsp12-nsp8F interactions (nsp12-V330S, nsp12-V341S, and nsp8-R111A/D112A), also resulted in an impaired RdRp activity, further illustrating the importance of this contact interface in the regulation of RNA synthesis.


Assuntos
Mutação Puntual , RNA Viral , SARS-CoV-2 , Proteínas não Estruturais Virais , SARS-CoV-2/genética , SARS-CoV-2/metabolismo , Proteínas não Estruturais Virais/genética , Proteínas não Estruturais Virais/metabolismo , Proteínas não Estruturais Virais/química , RNA Viral/genética , RNA Viral/metabolismo , Humanos , RNA-Polimerase RNA-Dependente de Coronavírus/genética , RNA-Polimerase RNA-Dependente de Coronavírus/metabolismo , Polimerização , COVID-19/virologia , Substituição de Aminoácidos , RNA Polimerase Dependente de RNA/genética , RNA Polimerase Dependente de RNA/metabolismo , Modelos Moleculares
10.
BMC Res Notes ; 17(1): 199, 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39026307

RESUMO

OBJECTIVE: Environmental DNA (eDNA) detection is a transformative tool for ecological surveys which in many cases offers greater accuracy and cost-effectiveness for tracking low-density, cryptic species compared to conventional methods. For the use of targeted quantitative PCR (qPCR)-based eDNA detection, protocols typically require freshly prepared reagents for each sample, necessitating systematic evaluation of reagent stability within the functional context of eDNA standard curve preparation and environmental sample evaluation. Herein, we assessed the effects of long-term storage and freeze-thaw cycles on qPCR reagents for eDNA analysis across six assays. RESULTS: Results demonstrate qPCR plates (containing pre-made PCR mix, primer-probe, and DNA template) remain stable at 4 °C for three days before thermocycling without fidelity loss irrespective of qPCR assay used. Primer-probe mixes remain stable for five months of - 20 °C storage with monthly freeze-thaw cycles also irrespective of qPCR assay used. Synthetic DNA stocks maintain consistency in standard curves and sensitivity for three months under the same conditions. These findings enhance our comprehension of qPCR reagent stability, facilitating streamlined eDNA workflows by minimizing repetitive reagent preparations.


Assuntos
DNA Ambiental , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase em Tempo Real/métodos , Reação em Cadeia da Polimerase em Tempo Real/normas , DNA Ambiental/análise , DNA Ambiental/genética , Indicadores e Reagentes , Congelamento , Primers do DNA/genética , Manejo de Espécimes/métodos
11.
Int J Biol Macromol ; : 134175, 2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-39067728

RESUMO

A target-induced multiregion MNAzyme nanowire system is designed for the ultrasensitive and homogeneous detection of microRNAs (miRNAs). miRNA-21 and miRNA-375 are chosen as analytes, and a miRNA-induced primer exchange reaction (PER) is utilized to construct a long DNA strand with repetitive sequences. This innovative design enables the efficient anchoring of numerous MNAzymes. This unique architecture significantly boosts the effective local concentration of MNAzymes, thereby enhancing the sensitivity and efficiency of miRNA detection. Notably, the limit of detection (LOD) achieved with our target-induced multiregion MNAzyme nanowire approach is over an order of magnitude lower than most other MNAzyme-based methods, while the MNAzyme reaction time is reduced from several hours to 50 min. The method has demonstrated successful applications in quantitatively determining the expression levels of two miRNAs in cell lysates of MCF-7, HeLa and MCF-10 A cells, highlighting its potential for assaying miRNA biomarkers in clinical samples.

12.
Front Microbiol ; 15: 1424795, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39077744

RESUMO

Compared with 454 sequencing technology, short-read sequencing (e.g., Illumina) technology generates sequences of high accuracy, but limited length (<500 bp). Such a limitation can prove that studying a target gene using a large amplicon (>500 bp) is challenging. The ammonia monooxygenase subunit A (amoA) gene of ammonia-oxidizing archaea (AOA), which plays a crucial part in the nitrification process, is such a gene. By providing a full overview of the community of a functional microbial guild, 16S ribosomal ribonucleic acid (rRNA) gene sequencing could overcome this problem. However, it remains unclear how 16S rRNA primer selection influences the quantification of relative abundance and the identification of community composition of nitrifiers, especially AOA. In the present study, a comparison was made between the performance of primer pairs 338F-806R, 515F-806R, and 515F-907R to a shotgun metagenome approach. The structure of nitrifier communities subjected to different long-term organic matter amendment and water management protocols was assessed. Overall, we observed higher Chao1 richness diversity of soil total bacteria by using 515F-806R compared to 338F-806R and 515F-907R, while higher Pielou's evenness diversity was observed by using 515F-806R and 515F-907R compared to 338F-806R. The studied primer pairs revealed different performances on the relative abundance of Thaumarchaeota, AOB, and NOB. The Thaumarchaeota 16S rRNA sequence was rarely detected using 338F-806R, while the relative abundances of Thaumarchaeota detected using 515F-806R were higher than those detected by using 515F-907R. AOB showed higher proportions in the 338F-806R and 515F-907R data, than in 515F-806R data. Different primers pairs showed significant change in relative proportion of NOB. Nonetheless, we found consistent patterns of the phylotype distribution of nitrifiers in different treatments. Nitrosopumilales (NP) and Nitrososphaerales (NS) clades were the dominant members of the AOA community in soils subject to controlled irrigation, whereas Ca. Nitrosotaleales (NT) and NS clades dominated the AOA community in soils subject to flooding irrigation. Nitrospira lineage II was the dominant NOB phylotype in all samples. Overall, ideal 16S rRNA primer pairs were identified for the analysis of nitrifier communities. Moreover, NP and NT clades of AOA might have distinct environmental adaptation strategies under different irrigation treatments.

13.
Biochem Genet ; 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39080126

RESUMO

As a tool for acquiring uncharacterized genomic DNA adjacent to characterized DNA, genome-walking is integral to bioscience-related research works. Herein, a new genome-walking tool known as N7-ended walker PCR (polymerase chain reaction) is presented. The key aspect for this method is the use of a degenerate walker primer in secondary/tertiary PCR. The 7 nt 5' tail of this primer completely degenerates to N7 relative to its corresponding primary walker primer. The degeneracy reduces the efficiency of annealing this primer to its predecessor site. Clearly, primary nontarget DNA defined by the primary walker primer prefers to form a hairpin structure via the inverted ends rather than hybridizing with the degenerate primer. As a result, N7-ended walker PCR achieves genome-walking by selectively boosting the DNA of interest. The feasibility of the N7-ended walker PCR method was proven by acquiring uncharacterized DNAs flanking several characterized DNAs.

14.
Methods Mol Biol ; 2812: 193-201, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39068363

RESUMO

Our laboratory is interested in investigating the maturation process of zebrafish thrombocytes, which are functional equivalents to human platelets. We have adopted the zebrafish model to gain insights into mammalian platelet production, or thrombopoiesis. Notably, zebrafish exhibit two distinct populations of thrombocytes in their circulating blood: young and mature thrombocytes. This observation is intriguing because maturation appears to occur in circulation, yet the precise mechanisms governing this maturation remain elusive. Our goal is to understand the mechanisms underlying thrombocyte maturation by conducting single-cell RNA sequencing (scRNA-Seq) on young and mature thrombocytes, analyzing these transcriptomes to identify genes specific to each thrombocyte population, and elucidating the role of these genes in the maturation process, by quantifying thrombocyte numbers after the piggyback knockdown of each of these genes. In this chapter, we present a comprehensive, step-by-step protocol detailing the multifaceted methodology involved in understanding thrombocyte maturation, which encompasses the collection of zebrafish blood, the separation of young and mature thrombocytes using flow cytometry, scRNA-Seq analysis of these distinct thrombocyte populations, identification of genes specific to young and mature thrombocytes, and subsequent validation through gene knockdown techniques.


Assuntos
Plaquetas , Perfilação da Expressão Gênica , Análise de Célula Única , Transcriptoma , Peixe-Zebra , Peixe-Zebra/genética , Animais , Plaquetas/metabolismo , Perfilação da Expressão Gênica/métodos , Análise de Célula Única/métodos , Genômica/métodos , Trombopoese/genética , Citometria de Fluxo , Análise de Sequência de RNA/métodos , Humanos
15.
Anal Biochem ; 694: 115621, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39019205

RESUMO

Mutational study is a cornerstone methodology in biochemistry and genetics, and many mutagenesis strategies have been invented to promote the efficiency of gene engineering. In this study, we developed a simple and timesaving approach to integrate simultaneous mutagenesis at discrete sites. By using plasmid as a template and compatible oligonucleotide primers per the QuikChange strategy, our method was able to introduce multiple nucleotide insertions, deletions and replacements in one round of polymerase chain reaction. The longest insertion and deletion were achieved with 28 bp and 16 bp mismatch respectively. For minor nucleotide replacements (mismatch no more than 4 bp), mutations were achieved at up to 4 discrete locations. Usually, a successful clone with all desired mutations was found by screening 5 colonies. Clones with a subset of mutations may be stocked into the library of mutants or used as templates in the next rounds of mutagenic PCR to accomplish the entire construction project. This method can be applied to build up a combinatory library of mutants through saturation mutagenesis at multiple sites. It is promising to facilitate the research of protein biochemistry, forward genetics and synthetic biology.

16.
J Nematol ; 56(1): 20240023, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38975564

RESUMO

Recombinase polymerase amplification (RPA) is an isothermal in vitro nucleic acid amplification technique that has been adopted for simple, robust, rapid, reliable diagnostics of nematodes. In this study, the real-time RPA assay and RPA assay combined with lateral flow dipsticks (LF-RPA) have been developed targeting the ITS rRNA gene of the British root-knot nematode, Meloidogyne artiellia. The assay provided specific and rapid detection of this root-knot nematode species from crude nematode extracts without a DNA extraction step with a sensitivity of 0.125 second-stage juvenile (J2) specimen per a reaction tube for real-time RPA during 11 min and a sensitivity of 0.5 J2 specimens per a reaction tube for LF-RPA during 25 min. The RPA assays were validated with a wide range of non-target root-knot nematodes. The LF-RPA assay has great potential for nematode diagnostics in the laboratory having minimal available equipment.

17.
Mol Med Rep ; 30(3)2024 09.
Artigo em Inglês | MEDLINE | ID: mdl-38963022

RESUMO

As sequencing technology transitions from research to clinical settings, due to technological maturity and cost reductions, metagenomic next­generation sequencing (mNGS) is increasingly used. This shift underscores the growing need for more cost­effective and universally accessible sequencing assays to improve patient care and public health. Therefore, targeted NGS (tNGS) is gaining prominence. tNGS involves enrichment of target pathogens in patient samples based on multiplex PCR amplification or probe capture with excellent sensitivity. It is increasingly used in clinical diagnostics due to its practicality and efficiency. The present review compares the principles of different enrichment methods. The high positivity rate of tNGS in the detection of pathogens was found in respiratory samples with specific instances. tNGS maintains high sensitivity (70.8­95.0%) in samples with low pathogen loads, including blood and cerebrospinal fluid. Furthermore, tNGS is effective in detecting drug­resistant strains of Mycobacterium tuberculosis, allowing identification of resistance genes and guiding clinical treatment decisions, which is difficult to achieve with mNGS. In the present review, the application of tNGS in clinical settings and its current limitations are assessed. The continued development of tNGS has the potential to refine diagnostic accuracy and treatment efficacy and improving infectious disease management. However, further research to overcome technical challenges such as workflow time and cost is required.


Assuntos
Doenças Transmissíveis , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Doenças Transmissíveis/diagnóstico , Doenças Transmissíveis/microbiologia , Doenças Transmissíveis/genética , Metagenômica/métodos , Técnicas de Diagnóstico Molecular/métodos
18.
Small ; : e2402895, 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39023080

RESUMO

Acute myocardial infarction (AMI) is one of the major causes of death worldwide, posing significant global health challenges. Circular RNA (circRNA) has recently emerged as a potential diagnostic biomarker for AMI, providing valuable information for timely medical care. In this work, a new electrochemical method for circRNA detection by engineering a collaborative CRISPR-Cas system is developed. This system integrates the unique circRNA-targeting ability with cascade trans-cleavage activities of Cas effectors, using an isothermal primer exchange reaction as the bridge. Using cZNF292, a circulating circRNA biomarker for AMI is identified by this group; as a model, the collaborative CRISPR-Cas system-based method exhibits excellent accuracy and sensitivity with a low detection limit of 2.13 × 10-15 m. Moreover, the method demonstrates a good diagnostic performance for AMI when analyzing whole blood samples. Therefore, the method may provide new insight into the detection of circRNA biomarkers and is expected to have great potential in AMI diagnosis in the future.

19.
BMC Genomics ; 25(1): 594, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38867172

RESUMO

BACKGROUND: Reverse transcription quantitative PCR (RT-qPCR) with intercalating dyes is one of the main techniques to assess gene expression levels used in basic and applied research as well as in diagnostics. However, primer design for RT-qPCR can be complex due to the high demands on primer quality. Primers are best placed on exon junctions, should avoid polymorphic regions, be specific to the target transcripts and also prevent genomic amplification accurately, among others. Current software tools manage to meet all the necessary criteria only insufficiently. Here, we present ExonSurfer, a novel, user-friendly web-tool for qPCR primer design. RESULTS: ExonSurfer combines the different steps of the primer design process, encompassing target selection, specificity and self-complementarity assessment, and the avoidance of issues arising from polymorphisms. Amplification of potentially contaminating genomic DNA is avoided by designing primers on exon-exon junctions, moreover, a genomic alignment is performed to filter the primers accordingly and inform the user of any predicted interaction. In order to test the whole performance of the application, we designed primer pairs for 26 targets and checked both primer efficiency, amplicon melting temperature and length and confirmed the targeted amplicon by Sanger sequencing. Most of the tested primers accurately and selectively amplified the corresponding targets. CONCLUSION: ExonSurfer offers a comprehensive end-to-end primer design, guaranteeing transcript-specific amplification. The user interface is intuitive, providing essential specificity and amplicon details. The tool can also be used by command line and the source code is available. Overall, we expect ExonSurfer to facilitate RT-qPCR set-up for researchers in many fields.


Assuntos
Primers do DNA , Éxons , Internet , Software , Primers do DNA/genética , Humanos , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos
20.
Plant Commun ; : 100983, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38845197

RESUMO

Whole-genome genotyping (WGG) stands as a pivotal element in genomic-assisted plant breeding. Nevertheless, sequencing-based approaches for WGG continue to be costly, primarily owing to the high expenses associated with library preparation and the laborious protocol. During prior development of foreground and background integrated genotyping by sequencing (FBI-seq), we discovered that any sequence-specific primer (SP) inherently possesses the capability to amplify a massive array of stable and reproducible non-specific PCR products across the genome. Here, we further improved FBI-seq by replacing the adapter ligated by Tn5 transposase with an arbitrary degenerate (AD) primer. The protocol for the enhanced FBI-seq unexpectedly mirrors a simplified thermal asymmetric interlaced (TAIL)-PCR, a technique that is widely used for isolation of flanking sequences. However, the improved TAIL-PCR maximizes the primer-template mismatched annealing capabilities of both SP and AD primers. In addition, leveraging of next-generation sequencing enhances the ability of this technique to assay tens of thousands of genome-wide loci for any species. This cost-effective, user-friendly, and powerful WGG tool, which we have named TAIL-PCR by sequencing (TAIL-peq), holds great potential for widespread application in breeding programs, thereby facilitating genome-assisted crop improvement.

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