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Methylation-based droplet digital polymerase chain reaction shows high concordance with chronic lymphocytic leukemia IGHV somatic mutation status.

OBJECTIVE: Somatic hypermutation at immunoglobulin heavy chain variable (IGHV) genes, an established prognostic and predictive biomarker for chronic lymphocytic leukemia (CLL), is assessed by gene sequencing. We developed a single methylation-specific droplet digital polymerase chain reaction (methyl-ddPCR) to predict IGHV status in patients with CLL. METHODS: The CLL methylation array and IGHV data from the International Cancer Genome Consortium (ICGC) were used for biomarker discovery. Top-ranked candidate regions were manually screened for PCR primer and probe binding sites. A single methyl-ddPCR was evaluated on an internal cohort of CLLs with mutated (M), unmutated (U), and inconclusive IGHV results originally determined by next-generation sequencing (NGS). RESULTS: Analysis of ICGC data identified array probe cg23844018 as a candidate for the PCR. The corresponding CpG site showed high methylation levels in U-CLL and lower levels in M-CLL. On the internal cohort, a single optimal cutoff correctly classified 104 of 115 U- and M-CLLs (90.4%; area under the curve = 0.96). The PCR data correlated with some prognostic fluorescence in situ hybridization and CLL subset groupings. Limited analysis suggests that the PCR may be able to stratify some patients with CLL who have inconclusive results on IGHV NGS testing. CONCLUSIONS: The methyl-ddPCR showed high concordance with CLL IGHV status in an internal cohort.

Humans

Bioinformatics and Quantitative Real-Time Polymerase Chain Reaction Analysis of SUCNR1 and GPR37L1 in Schizophrenia.

Schizophrenia is a severe, complex, and multifactorial mental disorder involving numerous genetic susceptibility elements, leading to substantial disability, morbidity, and mortality. Despite significant progress in understanding its pathophysiology and etiology, specific diagnostic biomarkers for schizophrenia remain elusive. This study aimed to identify candidate molecular markers associated with schizophrenia. An integrated bioinformatics analysis was performed on the public microarray dataset GSE54913. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses revealed that the most significantly enriched GO terms were related to channel activity, including passive transmembrane transporter activity, ion channel activity, gated channel activity, and substrate-specific channel activity. The top five enriched KEGG pathways were insulin secretion, cAMP signaling pathway, nucleotide excision repair, TNF signaling pathway, and glutathione metabolism. Validation was conducted using quantitative real-time polymerase chain reaction (qRT-PCR) on an independent sample set from Wuhan Rongjun Youfu Hospital. The qRT-PCR results were largely consistent with the microarray analysis (Pearson r = 0.89, 95% CI: 0.66-0.97). Protein-protein interaction (PPI) network analysis identified two hub genes, SUCNR1 and GPR37L1, which were significantly associated with the GO term 'ion channel activity' and enriched in the KEGG pathway 'insulin secretion'. Furthermore, SUCNR1 expression showed a negative correlation with verbal memory scores (r = -0.54, P = 0.015), whereas GPR37L1 expression showed a positive correlation (r = 0.59, P = 0.0034). These findings suggest that altered SUCNR1 and GPR37L1 expression may be associated with schizophrenia and may represent candidate molecular markers for further investigation.

Humans

Development of a Real-Time Reverse Transcription Polymerase Chain Reaction Assay for Una Virus.

Una virus (UNAV) is an understudied alphavirus with the capacity to infect humans. Although it was discovered decades ago in South America, little is still known about this virus because accurate diagnostic tests are still needed. The first UNAV-specific real-time reverse transcription polymerase chain reaction (rRT-PCR) test is described in the present study. This assay targets the nonstructural protein 1 coding region and was designed from an alignment using all available UNAV sequences. The linear range of the UNAV rRT-PCR extended from 6.2 to 0.2 log10 copies/µL, with a lower limit of 95% detection of 2.0 copies/µL. The assay offered sensitive UNAV detection in contrived whole-blood samples. In addition, no amplification was observed in the assay when tested with genomic RNA from multiple closely related arboviruses. The UNAV rRT-PCR exhibits high sensitivity and specificity, which is critical for research into this virus in regions where multiple related alphaviruses co-circulate.

Journal Article

Development of a Multiplex Polymerase Chain Reaction Assay for Differentiating Three Lactococcus Species Associated With Piscine Lactococcosis.

Piscine lactococcosis is an important bacterial disease of farmed fish. The causative agents, Lactococcus garvieae, Lactococcus petauri and Lactococcus formosensis, are closely related, which complicates species-level identification. We developed a conventional multiplex PCR assay targeting species-specific genes identified by comparative genomic analysis. Average nucleotide identity reassignment of 441 publicly available genome assemblies identified 111 L. garvieae, 255 L. petauri and 75 L. formosensis genomes. Species-specific primers and a tuf-based Lactococcus common control were evaluated using in silico polymerase chain reaction (PCR) against target genomes and 10,460 off-target assemblies representing 474 taxa in 12 genera. Experimental specificity was assessed using six target strains and 19 non-target fish pathogens. Distinct amplicons of 195, 333 and 500 bp were produced for L. garvieae, L. petauri and L. formosensis, respectively, together with a 132-bp control amplicon. No cross-amplification was observed. All target species were detected in mixed-DNA samples and spiked kidney and spleen homogenates from two fish species. Analytical detection limits were estimated based on microscopic cell counts of bacterial suspensions before DNA extraction and ranged from 0.956 to 8.55 cell equivalents per reaction. This assay represents a rapid, low-cost method for differentiating lactococcosis-causing Lactococcus species using standard PCR and agarose gel electrophoresis.

Lactococcus garvieae

The diagnostic potential of combined quantitative polymerase chain reaction and next-generation sequencing using the same primers for periprosthetic joint infection.

Next-generation sequencing (NGS) enables the detection of specific pathogens unidentifiable by conventional cultures, but its application in orthopedics remains inconsistent due to background contamination and irreproducible findings. This study evaluated the diagnostic performance of a novel workflow combining broad-range 16S rRNA gene quantitative PCR (qPCR) screening with downstream NGS, focusing on bacterial biomass thresholds. The qPCR assay demonstrated excellent intrarater reliability, with an intraclass correlation coefficient (ICC) of 0.961 (95% confidence interval, 0.881 to 0.997). Based on serially diluted positive controls, a quantitative threshold of 10⁵ CFU/mL was established as the minimum concentration required for the consistent detection of fastidious taxa, such as Escherichia coli. When evaluated against conventional cultures using 95 sonicate fluid and 276 pre/intraoperative tissue samples, the qPCR assay achieved a sensitivity of 80% and a specificity of 72%. Subsequent NGS sequencing of 26 clinical samples and 9 controls showed concordance in 4 of 6 culture-positive infected cases with NGS taxonomy, whereas the remaining discrepancies were likely attributable to culture-based phenotypic misidentification. Notably, among the qPCR-positive cases, three were culture-negative, including two hip prosthesis loosening cases exhibiting polymicrobial profiles, and one post-traumatic osteoarthritis case harboring low-level Staphylococcus. Crucially, this post-traumatic patient developed delayed periprosthetic joint infection (PJI) 2 years post-surgery, with cultures identifying Staphylococcus previously detected by the initial NGS analysis. Integrating qPCR screening with targeted NGS effectively refines pathogen identification, filters environmental artifacts, and overcomes the diagnostic limitations of culture-negative infections in orthopedic practice.IMPORTANCENext-generation sequencing (NGS) enables the detection of specific pathogens in clinical samples that are not identifiable by conventional methods. However, NGS applications in orthopedics have not been quantitatively evaluated, and findings have been inconsistent owing to contaminants and the presence of non-credible causative organisms. These factors primarily stem from the failure to evaluate low-biomass samples and the absence of proper controls, such as negative controls or mock community DNA samples. This study demonstrates that interpreting results from low-biomass samples requires careful consideration because NGS relies on relative bacterial abundances; distinguishing likely pathogens from contaminants is particularly challenging when bacterial loads are low. We demonstrated that combining NGS with quantitative PCR (qPCR) and applying a Cq cutoff can reduce false positives.

Humans

Hierarchical integration of mNGS, PCR, and other conventional methods for precision TB diagnostics.

UNLABELLED: This study systematically compared the diagnostic accuracy of seven assays for detecting the Mycobacterium tuberculosis complex, including metagenomic next-generation sequencing (mNGS), droplet digital polymerase chain reaction, real-time quantitative polymerase chain reaction, EasyNAT MTC, GeneXpert MTB/RIF, interferon-gamma release assay (IGRA), and acid&#x2012;fast staining (AFS). We try to select appropriate combinations of tuberculosis (TB) detection methods for regions with varying levels of medical resources, based on sensitivity, cost-effectiveness, and operational feasibility. A retrospective analysis was conducted on 141 samples collected from patients with suspected active TB at The First Affiliated Hospital of Sun Yat-sen University between April 2022 and April 2024. Among these samples, there were 100 cases assigned to the case group and 41 cases to the control group, based on the tuberculosis diagnostic criteria. Historical data for Xpert, IGRA, and AFS were collected, and parallel experiments using mNGS, droplet digital PCR (ddPCR), real-time quantitative polymerase chain reaction (RT-qPCR), and EasyNAT were conducted on all samples. Diagnostic performance was evaluated by comparing it with the final clinical diagnoses. Sensitivity, specificity, positive predictive value, negative predictive value, and receiver operating characteristic (ROC) curve analysis were conducted, along with DeLong tests for statistical comparison. Compared with the final clinical diagnosis, mNGS demonstrated the highest sensitivity (100%), followed by IGRA (79.2%), EasyNAT (79.1%), RT-qPCR (78.0%), ddPCR (75.8%), Xpert (75.3%), and AFS (16.7%). The specificity was 100% for both Xpert and AFS, followed by ddPCR (97.6%), RT-qPCR (95.1%), EasyNAT (92.7%), IGRA (72.7%), and mNGS (75.6%). ROC analysis revealed a significantly greater area under the ROC curve for mNGS (0.878) than for ddPCR (0.817, P = 0.031). DeLong tests revealed statistically significant differences in diagnostic performance between mNGS and ddPCR (P < 0.05) and between IGRA and AFS (P < 0.01). mNGS uniquely identified the pathogens involved in co-infection and quantified pathogen-specific sequencing reads. Through a comprehensive evaluation of the diagnostic efficacy, cost-effectiveness, and timeliness of tuberculosis detection methods, we propose corresponding combinations of TB testing approaches for regions with different healthcare resources. For undeveloped regions with limited resources, a combination of AFS +EasyNAT + chest X-ray is recommended. Primary care facilities may additionally employ IGRA + RT-qPCR. Intermediate-level hospitals can incorporate Xpert MTB/RIF for drug resistance testing, while tertiary hospitals or specialized centers should, on the basis of these fundamental tests, utilize mNGS for diagnosis and ddPCR for therapeutic monitoring in patients with complex mixed infections. IMPORTANCE: This study is the first to comprehensively evaluate the diagnostic efficacy, cost-effectiveness, and timeliness of seven TB detection methods in a single-center cohort. Our findings provide actionable solutions for optimizing TB diagnostics in diverse healthcare ecosystems, aligning with the WHO's End TB Strategy to ensure equitable access to rapid diagnostics.

Humans

Diagnostic utility of high-risk HPV polymerase chain reaction-based testing in head and neck FNA specimens with indeterminate cytomorphology.

BACKGROUND: Fine-needle aspiration (FNA) is critical in the initial diagnosis of many high-risk human papillomavirus (HR-HPV)-associated, metastatic oropharyngeal squamous cell carcinomas. Updated guidelines recommend HR-HPV-specific polymerase chain reaction (PCR) analysis over p16 immunohistochemistry on FNA specimens because p16 performs poorly on cytology material. PCR-based assays on liquid cytology material have demonstrated excellent analytic performance; however, the diagnostic utility of a positive HR-HPV PCR result in specimens with indeterminate cytomorphology remains uncharacterized. METHODS: The authors retrospectively identified 279 head and neck FNA specimens that had paired HR-HPV PCR testing on residual liquid cytology material over a 5-year period. The positive predictive value for histopathologically confirmed squamous cell carcinoma on surgical follow-up was calculated within each cytologic interpretive category. RESULTS: The HR-HPV PCR results were positive in 50.2% of specimens, negative in 40.9%, and indeterminate in 9.0%. The HR-HPV positivity rate ranged from 0% in specimens categorized as negative for malignancy to 57.3% in cytologically positive specimens, with 19.0%, 41.2%, and 50.0% positivity in the atypical, suspicious, and nondiagnostic categories, respectively. Among cytologically indeterminate specimens with positive HR-HPV PCR results (n&#xa0;=&#xa0;14), the positive predictive value was 100% (95% confidence interval, 78.5%-100.0%). Blinded slide review additionally identified 15 cytologically positive specimens in which the definitive malignant interpretation depended substantially on HR-HPV positivity; all 15 were confirmed as squamous cell carcinoma. CONCLUSIONS: A positive HR-HPV PCR result on liquid cytology material carries a positive predictive value of 100% for malignancy in cytologically indeterminate head&#xa0;and neck FNA specimens. These findings support integrating HR-HPV PCR analysis into routine cytologic interpretation with the potential to upgrade some indeterminate specimens to malignant when HR-HPV is detected, expediting definitive treatment and sparing patients additional, invasive sampling.

Humans

Bridging the gap between legacy polymerase chain reaction-based microsatellite data with high-throughput sequencing data for conservation genomics.

Microsatellites are powerful markers for tracking genetic variation in wildlife populations due to their high polymorphism and genome-wide abundance. While polymerase chain reaction (PCR)-based fragment size analysis has been the standard for genotyping microsatellites, high-throughput sequencing offers greater resolution and the opportunity to sync historical datasets with modern analyses. We evaluated how genotypes from whole-genome sequencing align with PCR data for 15 microsatellite loci in 11 North American brown bears (Ursus arctos). Brown bear populations in the 48 contiguous United States have declined from approximately 50,000 to fewer than 2,000 over the past decades. Their endangered status has prompted extensive research and genetic monitoring, yielding large, multiyear microsatellite datasets upon which future conservation efforts can build. We achieved an overall microsatellite genotype concordance rate of 94.5% comparing high-throughput sequencing results to PCR based-fragment size results. All discrepancies occurred at complex loci containing multiple insertions and/or deletions (indels). Physically linked indels or single nucleotide polymorphisms (SNPs) occurring within the loci were misinterpreted as independent insertions, underscoring the need for genotyping tools that incorporate phasing when genotyping. To evaluate coverage effects, we downsampled high-throughput sequence data from 30x to 2x. Concordance remained high at 20 to 30x but dropped sharply at 10x, with 5x and 2x having discordant genotypes or insufficient coverage for genotyping. Accurate genotyping required both sufficient depth and number of reads spanning the entire repeat regions. Our results show that short-read whole-genome sequencing can recover microsatellite genotypes with high accuracy when paired with careful variant interpretation. By aligning historical PCR datasets with modern sequencing data, we can preserve decades of genetic insight and strengthen long-term monitoring of at-risk populations.

Animals

Non-invasive embryo assessment: Cell-free DNA-based genetic testing and amino acid metabolomics in relation to morphology: A case-control study.

BACKGROUND: Cell-free DNA (cfDNA) in spent culture medium (SCM) offers a non-invasive option for preimplantation genetic testing, but its low concentration and fragmentation reduce clinical reliability. Combining genetic assessment with metabolomic profiling may provide complementary information about embryo competence. OBJECTIVE: This study assessed pre-analytical cfDNA processing workflows and examined whether SCM amino acid metabolic patterns could act as practical markers of embryo quality. MATERIALS AND METHODS: In this case-control study (2021-2023), 90 embryos were evaluated using fluorescence in situ hybridization or array comparative genomic hybridization. SCM samples underwent rapid boiling, silica-based purification, or whole-genome amplification (WGA). Sex determination was performed using quantitative polymerase chain reaction (qPCR). For cfDNA quality control and aneuploidy screening, the multiplex IRFiling kit and quantitative fluorescent polymerase chain reaction (QF-PCR) were used. Amino acid profiles across embryonic developmental stages and quality grades were quantified via liquid chromatography-tandem mass spectrometry. RESULTS: Rapid boiling resulted in complete failure of DNA amplification. Conversely, silica-based purification yielded 70.0% concordance for qPCR-based sexing and 56.7% for QF-PCR. WGA achieved the highest efficacy (73.3% qPCR and 56.7% QF-PCR concordance), although quality control checks flagged occasional misclassifications. LC-MS/MS profiling revealed significantly elevated alanine and arginine levels in tripronuclear embryos. Furthermore, high-quality blastocysts exhibited elevated glutamic acid levels alongside a pronounced overall depletion of extracellular amino acids compared to low-quality counterparts and controls. CONCLUSION: WGA improves cfDNA detectability and qPCR accuracy compared with boiling or purification, but remains inadequate as a standalone screening approach. SCM amino acid profiling provides informative, complementary metabolic signatures of developmental competence, supporting a multimodal strategy for non-invasive embryo assessment.

Amino acid metabolism

Improving isolate recovery and identification of the Shiga toxin type in Shiga toxin nucleic acid test-positive feces.

UNLABELLED: Infections caused by Shiga toxin-producing Escherichia coli (STEC) strains carrying Shiga toxin 2 (stx2) are more likely to result in severe complications; however, most nucleic acid amplification tests used for STEC diagnosis do not differentiate between stx1 and stx2. We therefore sought to optimize stx typing and isolate recovery methods to guide clinical and public health management. stx polymerase chain reaction (PCR)-positive feces were cultured using CHROMagar STEC and gram-negative broth, with Stx1 and/or Stx2 antigen detection by enzyme immunoassay (EIA) on colony growth or turbid broth. When cultures were EIA-negative, growth from MacConkey agar (MAC), Trypticase soy broth, and the gram-negative broth was then tested using a lab-developed typing PCR for stx1 and stx2. Colonies were isolated on CHROMagar STEC or MAC and identified using the typing PCR. Using both EIA and typing PCR, the stx types were identified in 96.0% of cases (381/397). In 65.2% (259/397) of cases, culture was EIA-positive, of which 34.0% (87/256) were Stx2-positive. Among cultures that were EIA-negative but typing PCR-positive, 64.8% (79/122) were stx2-positive (P < 0.0001 compared to EIA-positive). Using both EIA and typing PCR resulted in 72.6% (286/394) of cases with successful attempts at isolate recovery, compared to 60.7% (239/394) with EIA alone. E. coli O157 was recovered from more EIA-positive cases (19.3%, 46/239) than EIA-negative ones (4.3%, 2/47) (P = 0.0097). Typing PCR on cultures improves stx typing (particularly stx2) and isolate detection compared to EIA alone. Screening BD Max PCR and subsequent typing PCR results showed excellent concordance. IMPORTANCE: Escherichia coli strains with one or both types of Shiga toxins (stx1 and stx2) are a common cause of bacterial diarrhea and can lead to serious complications such as kidney failure, especially in children. Infection by stx2-positive strains is more likely to do so. Therefore, knowing whether the infection is caused by a strain carrying stx2 is important for risk assessment and case follow-up. The conventional way to diagnose these infections is to grow the bacteria from stool, but most laboratories currently use nucleic acid detection (e.g., bacterial DNA detection by polymerase chain reaction [PCR]), and these assays do not differentiate between the two toxin genes. Culture is therefore required to determine toxin type, as well as for public health outbreak investigations, which require an isolate for whole-genome sequencing for serotyping and cluster analysis. We identified culture media and a PCR-based method to detect stx2 in culture that improved the detection of stx2 and isolate recovery. Our findings provide more accurate results for clinicians to improve patient care and tools for public health teams to control and prevent outbreaks.

Humans

KIT and FLT3-ITD mutations do not predict outcomes in pediatric core-binding factor acute myeloid leukemia: findings from the C-HUANAN-AML-15 multicenter cohort study.

Although core-binding factor acute myeloid leukemia (CBF-AML) is generally considered a favorable-risk subtype in children, disease relapse remains a significant concern. The prognostic relevance of co-occurring mutations, particularly KIT and FLT3-ITD, remains debatable, and treatment intensity may modulate their impact. This multicenter analysis included 289 children (<&#x2009;14 years) with newly diagnosed CBF-AML enrolled in the C-HUANAN-AML-15 study (2015-2023). KIT and FLT3-ITD mutations were identified via cytogenetic analysis and targeted sequencing. Measurable residual disease (MRD) was evaluated by multiparameter flow cytometry (MFC) and quantitative polymerase chain reaction (PCR) following induction chemotherapy. Survival analyses were performed using Kaplan-Meier and Cox regression methods. This multicenter analysis included 289 children (<&#x2009;14 years) with newly diagnosed CBF-AML enrolled in the C-HUANAN-AML-15 study (2015-2023). KIT and FLT3-ITD mutations were identified via cytogenetic analysis and targeted sequencing. Measurable residual disease (MRD) was evaluated by multiparameter flow cytometry (MFC) and quantitative polymerase chain reaction (PCR) following induction chemotherapy. Survival analyses were performed using Kaplan-Meier and Cox regression methods. KIT mutations were detected in 103 patients (35.6%), predominantly involving exon 17 (69.9%), and were associated with extramedullary disease, sex chromosome loss, and trisomy 22. No significant differences in 5-year event-free survival (EFS), overall survival (OS), or cumulative incidence of relapse (CIR) were observed between patients with and without KIT mutations. FLT3-ITD mutations (5.5% of patients) did not adversely affect outcomes. Neither mutation independently predicted survival. MRD positivity (MFC-MRD&#x2009;&#x2265;&#x2009;0.1%) after the second induction cycle strongly predicted inferior EFS and OS and higher CIR, with corresponding results observed for molecular MRD and parallel findings for PCR-based MRD. In this large multicenter cohort, KIT and FLT3-ITD mutations did not adversely affect the prognosis of pediatric CBF-AML treated according to the C-HUANAN-AML-15 protocol. MRD after induction was the most powerful predictor of relapse and survival, underscoring its importance for risk stratification in future pediatric AML trials.

Humans

Identification and analysis of key genes related to efferocytosis in colorectal cancer.

UNLABELLED: The impact of efferocytosis-related genes (ERGs) on the diagnosis of colorectal cancer (CRC) remains unclear. In this study, efferocytosis-associated biomarkers for the diagnosis of CRC were identified by integrating data from transcriptome sequencing and public databases. Finally, the expression of biomarkers was validated by real-time quantitative polymerase chain reaction (RT-qPCR). Our study may provide a reference for CRC diagnosis. BACKGROUND: It has been shown that some efferocytosis related genes (ERGs) are associated with the development of cancer. However, it is still uncertain how ERGs may influence the diagnosis of colorectal cancer (CRC). METHODS: In our study, the CRC cohorts were gained from transcriptome sequencing and the gene expression omnibus (GEO) database (GSE71187). Efferocytosis related biomarkers with diagnostic utility for CRC were identified through combining differentially expressed analysis, machine learning algorithms, and receiver operating characteristic (ROC) analysis. Then, infiltration abundance of immune cells between CRC and control was evaluated. The regulatory networks (including mRNA-miRNA-lncRNA and miRNA/transcription factors (TF)-mRNA networks) were created. Finally, the expression of biomarkers was validated via real-time quantitative polymerase chain reaction (RT-qPCR). RESULTS: There were 3 biomarkers (ELMO3, P2RY12, and PDK4) related diagnosis for CRC patients gained. ELMO3 was highly expressed in CRC group, while P2RY12 and PDK4 was lowly expressed. Besides, the infiltrating abundance of 3 immune cells between CRC and control groups was significantly differential, namely activated CD4 memory T cells, macrophages M0, and resting mast cells. We then constructed a mRNA-miRNA-lncRNA network containing 3 mRNAs, 33 miRNAs, and 22 lncRNAs, and a miRNA/TF-mRNA network including 3 mRNAs, 33 miRNAs, and 7 TFs. Additionally, RT-qPCR results revealed that the expression trends of all biomarkers were consistent with the transcriptome sequencing data and GSE71187. CONCLUSION: Taken together, this study provides three efferocytosis related biomarkers (ELMO3, P2RY12, and PDK4) for diagnosis of CRC, providing a scientific reference for further studies of CRC.

Humans

Amplification of Filovirus Genomes from Clinical Samples for Next Generation Sequencing.

Viral genome sequencing has become a critical tool in outbreak mitigation. Due to their small size relative to the host genome, viral genomes comprise a small fraction of next generation sequencing reads in clinical samples when using unbiased sequencing approaches. Long-range polymerase chain reaction facilitates the amplification of viral genomes from clinical and environmental samples with minimal primer sites, allowing researchers to target regions of the genome that are conserved across available variants. Here, we describe the amplification and sequencing of the Ebola virus genome from tissue samples collected from infected nonhuman primates. This protocol facilitates full viral genome recovery from as low as 103 median tissue culture infectious doses per milliliter.

High-Throughput Nucleotide Sequencing

Measuring FOXO Activity by Using qPCR-Based Expression Analysis of FOXO Target Genes.

FOXO transcription factors belong to the forkhead protein family and are distinguished by their unique forkhead (FKH) DNA-binding domain. In the realm of mammals, four FOXO paralogs are recognized: FOXO1, FOXO3, FOXO4, and FOXO6. These paralogs are evolutionary counterparts of the daf-16 gene discovered in the nematode C. elegans. A key feature shared by these paralogs is a consensus binding site known as the DAF-16 family protein-binding site (DBE: 5'-TTGTTTAC-3'). The functional outcome of FOXO transcription factors primarily hinges on their affinity for these specific binding sites within the promoters of their target genes. Nevertheless, it is worth noting that many of these target genes exhibit tissue-specific expression patterns. Consequently, there is not a single FOXO target gene whose expression can reliably serve as a universal indicator of FOXO activity across all cell types and tissues or in response to all stimuli. In light of these considerations, we present a collection of target genes that, when collectively assessed, can accurately gauge FOXO activation. In this chapter, we outline a specific protocol for utilizing quantitative reverse transcription polymerase chain reaction (qRT-PCR) to measure the expression levels of these genes.

Forkhead Transcription Factors

Evaluation of one-step amplicon-based targeted enrichment for SARS-CoV-2 whole-genome sequencing using the Midnight amplicon scheme.

Genomic surveillance proved invaluable during the COVID-19 pandemic for tracking SARS-CoV-2 variants and guiding outbreak responses, underscoring the ongoing need to reduce whole-genome sequencing (WGS) costs and improve workflow efficiency to ensure accessibility in resource limited settings. Here, we evaluated a one-step reverse transcription polymerase chain reaction (RT-PCR) approach using the Midnight V2 primer scheme for targeted amplification of the SARS-CoV-2 genome, assessed its compatibility with Illumina sequencing, and compared its performance to a well-established two-step method. Initially, we determined optimal RT-PCR reaction conditions using the Midnight V2 primer panel for the one-step RT-PCR kit and scaled reaction volumes for both RT-PCR and library preparation. Clinical specimens (n&#x202f;=&#x202f;53) that had undergone routine WGS for surveillance purposes using the established two-step RT-PCR method were compared using the one-step RT-PCR assay. For samples with genome completeness greater than 70%, both methods gave comparable results with similar sequence coverage and 100% concordance for lineage assignment. Further investigation revealed a higher percentage of reads aligning to the SARS-CoV-2 genome with a greater depth of coverage using the one-step method compared to the two-step method. Finally, analysis of scaled one-step and library reaction volumes revealed significant cost savings for samples undergoing WGS. Overall, the results presented here verify the accuracy and reproducibility of one-step targeted amplification and offer an efficient and cost-effective workflow for routine SARS-CoV-2 genomic surveillance.

Humans

Designated primers targeted canine TP53 gene hotspot regions.

BACKGROUND: Tumor protein 53 gene (TP53) is a critical factor that controls different cell activities such as cell cycle, DNA repair mechanism, autophagy, apoptosis, and metabolism. The TP53 gene is the most commonly mutated gene, especially in the 4-8 exons region. This mutation enhances the development of many abnormalities, such as the initiation of different types of cancer. AIM: The main objective of this study was to design and evaluate the efficacy of three different primer sets that targeted the TP53 gene at the hotspot regions. METHODS: To do that, twelve blood samples were collected from dogs belonging to the German Shepherd breed/K9 aged between 8-12 years. Then, the DNA extraction and polymerase chain reaction (PCR) took place by using the three primer sets, which were designed using SnapGene. The primer sets, namely, first primer, the second and the third targeted exons 5-9 located in the canine TP53 gene. In the following step, all the PCR products were sent for Sanger sequencing and then phylogenetic analysis. RESULTS: Our findings indicated that the first primer set consistently showed higher amplification signal efficiency and reduced dimer formation compared with the second and third primer sets, respectively, with a 60&#xba;C annealing temperature. In addition, all the sequenced samples aligned with the reference canine TP53 gene in the phylogenetic tree. CONCLUSION: This study offered the best TP53 primer design that targeted the hotspot regions of the canine TP53 gene for researchers who are interested in targeting such regions in this gene.

Animals

Nanoplate Digital PCR for Identification of &#x3b1;0-Thalassemia (SEA Deletion): Carrier Screening and Possible Application to Prenatal Diagnosis.

The Southeast Asian deletion (--SEA), the most prevalent &#x3b1;0-thalassemia mutation in Southeast Asia, is a major target of regional thalassemia prevention programs. Coinheritance of &#x3b1;0-thalassemia with other hemoglobinopathies, particularly hemoglobin E (Hb E), complicates routine hematological screening and requires reliable molecular confirmation. This study developed and validated a duplex nanoplate digital polymerase chain reaction (dPCR) assay for simultaneous identification of the wild-type &#x3b1;-globin and --SEA deletion alleles in a single reaction. The assay was established on the QIAcuity nanoplate platform and evaluated using 171 blinded leftover DNA specimens from individuals with Hb E. Diagnostic performance was compared with conventional gap-PCR. Distinct fluorescence amplitude patterns enabled discrimination among normal, heterozygous, and homozygous --SEA genotypes in a single closed tube. Among the 171 specimens, 70 were identified as --SEA carriers and 101 as non-carriers, showing 100% concordance with gap-PCR. All subjects with Hb E + A2 levels &#x2265; 25% were negative for the --SEA deletion, whereas 56.0% of those with levels < 25% carried the deletion. In the representative prenatal case, duplex dPCR accurately identified parental carrier status and a homozygous --SEA fetus. This assay provides an accurate and practical molecular confirmatory assay for thalassemia screening and prenatal diagnosis in Southeast Asia.

Humans

"Clinical efficacy and expression of antimicrobial resistance genes after using a novel herbal mouthwash compared to chlorhexidine: A Randomised controlled trial in generalised gingivitis patients".

OBJECTIVES: Chlorhexidine, the gold-standard mouthwash, has several disadvantages, like promotion of antimicrobial resistance. Herbal mouthwashes are emerging as alternatives to chlorhexidine. However, its impact on antimicrobial resistance remains unclear. The aim of the study was to compare the clinical efficacy and the expression of antimicrobial resistance genes of chlorhexidine with a novel herbal mouthwash. DESIGN: Sixty patients with generalised gingivitis were randomly assigned to two groups using block randomisation. After professional mechanical plaque removal patients were instructed to use either chlorhexidine or a novel herbal mouthwash (patented composition) for two weeks. Tetracycline resistance (tetM) and macrolide efflux (mefI) gene expression in subgingival plaque were analysed using real-time polymerase chain reaction. Intragroup comparisons were performed with a paired t-test and Wilcoxon signed-rank test for parametric and nonparametric data. Intergroup comparisons employed unpaired t-test, chi-square test, and Mann-Whitney test. RESULTS: A significant reduction in bleeding, plaque, pocket depth and and patient reported outcomes were noticed in both groups. But reduction in plaque was more significant in chlorhexidine group. tetM and mefI genes significantly upregulated in the chlorhexidine group, while it was downregulated with herbal mouthwash (fold change 1.79&#x202f;&#xb1;&#x202f;0.74 and 0.60&#x202f;&#xb1;&#x202f;0.43 for tetM, and 1.83&#x202f;&#xb1;&#x202f;0.87 and 0.51&#x202f;&#xb1;&#x202f;0.44 for mefI). However, patients' perception of taste, freshness, and overall satisfaction was better in the chlorhexidine group. CONCLUSIONS: The increased expression of antimicrobial resistance genes following chlorhexidine use warrants careful consideration. Herbal mouthwash is an effective, safer alternative with comparable clinical benefits and less impact on antimicrobial resistance.

Humans