quantitative real‐time PCR
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UNLABELLED: The aim of this study was to identify parameters influencing DNA extraction and PCR amplification efficiencies in an attempt to standardize Mucorales qPCR. The Fungal PCR Initiative Mucorales Laboratory Working Group distributed two panels of simulated samples to 26 laboratories: Panel A (six sera spiked with Mucorales DNA and one negative control serum) and Panel B (six Mucorales DNA extracts). Panel A underwent DNA extraction in each laboratory according to the local procedure and were sent to a central laboratory for testing using three different qPCR techniques: one in-house qPCR assay and two commercial assays (MucorGenius and Fungiplex). Panel B DNA extracts were PCR amplified in each laboratory using local procedures: nine in-house qPCR assays and two commercial kits (MucorGenius and MycoGENIE). All data were compiled and anonymously analyzed at the central laboratory. For Panel A, a total of six different automated platforms and five manual extraction methods were used. Positive rates were 64%, 70%, and 89%, for the MucorGenius, Fungiplex, and the in-house qPCR assay, respectively. Using a large volume of serum for DNA extraction provided the highest analytical sensitivity (82.5% for 1 mL compared with 62.7% for smaller volumes, P < 0.01). For Panel B, five in-house qPCR assays and two commercial kits had >78% positivity. Using larger PCR input volumes (≥7 μL) was associated with the highest sensitivity at 95.5% compared to 58.3% when lower input volumes were used (P < 0.01). Using larger sample volumes for nucleic acid extraction and DNA template volumes for PCR amplification significantly improves the performance of Mucorales qPCR when testing serum. IMPORTANCE: Mucormycosis is a life-threatening mold infection affecting immunosuppressed patients but also other patients with diabetes or trauma. Better survival is linked to shorter delays in diagnosis and treatment initiation. Detection of Mucorales-free DNA in serum or plasma using quantitative PCR allows a prompt diagnosis and earlier treatment. Several techniques and protocols of quantitative Mucorales PCR are used in Europe, and improving performance remains a common objective of laboratories participating in the fungal PCR Initiative Working Group. This study, which combined results from 26 laboratories in Europe, showed that the main parameters underpinning sensitivity are the preanalytical variables (volume of serum used for DNA extraction and DNA template volume), irrespective of the extraction platforms and qPCR assay/platform.
- MeSH
- diagnostické techniky molekulární normy metody MeSH
- DNA fungální * krev genetika MeSH
- kvantitativní polymerázová řetězová reakce * normy metody MeSH
- lidé MeSH
- Mucorales * genetika izolace a purifikace MeSH
- mukormykóza * diagnóza mikrobiologie krev MeSH
- senzitivita a specificita * MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- hodnotící studie MeSH
The largest obstacle in the promotion of biopesticides is the existence of counterfeit products available in the market. Identification and quantification of antagonistic organisms in biopesticide products are the key to the reduction of spurious microbial pesticides. In this study, we have developed a simple, sensitive, isothermal-based colourimetric assay for specific detection of Bacillus subtilis from the biopesticide formulations and soil samples. A region specific to B. subtilis which codes for shikimate dehydrogenase was identified through in silico analysis. We employed conventional PCR, loop-mediated isothermal amplification (LAMP), recombinase polymerase amplification (RPA), and qPCR for specific detection of B. subtilis in soil samples and biopesticide formulations. Specificity tests showed that the PCR primers amplified an amplicon of 521 bp in four strains of B. subtilis only, and no amplification was found in negative control samples. Similarly, the LAMP assay showed sky blue colour in all four strains of B. subtilis and violet colour in negative control samples. Whereas in the RPA assay, upon the addition of SYBR Green dye, a bright green colour was seen in B. subtilis strains, while a brick-red colour was observed in negative control samples by visualizing under a UV transilluminator. The qPCR assay showed specific amplifications with a Ct value of 12 for B. subtilis strains and no amplification in negative control samples. In the sensitivity test, PCR could amplify DNA of B. subtilis up to 500 pg/μL. DNA concentration as low as 10 pg/μL was enough to show the colour change in the LAMP as well as the RPA assays, whereas the qPCR assay showed sensitivity till 100 pg/μL. All four diagnostic assays developed in the study have been validated in soil samples and B. subtilis-based biopesticides. Compared to conventional PCR, the qPCR assay has the advantage of quantification and visualizing the result in real-time, whereas LAMP and RPA assays have the benefits of being colourimetric and less time-consuming. The other advantages are that the results can be visualized with the naked eye, and these assays do not require a costly thermal cycler and gel documentation system. Hence, LAMP and RPA assays are highly suitable for developing point-of-need diagnostic kits and, in turn, help regulators assess the quality of biopesticides in the market.
- MeSH
- alkoholoxidoreduktasy * genetika MeSH
- Bacillus subtilis * genetika izolace a purifikace enzymologie MeSH
- bakteriální proteiny genetika MeSH
- diagnostické techniky molekulární * metody MeSH
- kolorimetrie * metody MeSH
- kvantitativní polymerázová řetězová reakce MeSH
- půdní mikrobiologie MeSH
- senzitivita a specificita MeSH
- techniky amplifikace nukleových kyselin * metody MeSH
- Publikační typ
- časopisecké články MeSH
Mycoplasma spp. contamination is a major concern in laboratories handling cell cultures, and routine detection methods are usually time-consuming, laborious and lack sensitivity. This study presents a streamlined workflow integrating rapid thermal DNA extraction (99 °C-1 min) with a SYBR Green-based qPCR for Mycoplasma detection. High-coverage primers targeting an 86-bp region of the 16S rDNA were designed using 109 Mycoplasma spp. sequences from GeneBank. In silico analysis confirmed full primer annealing to major cell culture contaminants (M. arginini, M. hominis, M. orale, and M. hyorhinis). Upon thermal lysis and qPCR optimization, the yield of the protocol was equivalent to that of phenol-chloroform extraction plus qPCR, with a detection limit of 64 bacterial cells. Finally, the performance of the protocol was confirmed in cell cultures with known Mycoplasma spp. contamination, accurately reproducing the contamination status. Thus, the developed protocol provides a simple, rapid, cost-effective, and sensitive method for monitoring Mycoplasma spp. in cell cultures.
- MeSH
- buněčné kultury * metody MeSH
- DNA bakterií genetika izolace a purifikace MeSH
- DNA primery genetika MeSH
- kvantitativní polymerázová řetězová reakce * metody MeSH
- lidé MeSH
- Mycoplasma * genetika izolace a purifikace klasifikace MeSH
- průběh práce MeSH
- ribozomální DNA genetika MeSH
- RNA ribozomální 16S genetika MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
BACKGROUND: Severe combined immunodeficiency (SCID) is a fatal but treatable inborn error of immunity (IEI). Newborn screening (NBS) using T-cell receptor excision circles (TREC) has been adopted globally, with very few countries incorporating kappa recombination excision circles (KREC) to also detect early B-cell development disorders, such as X-linked agammaglobulinemia (XLA). OBJECTIVE: To evaluate the effectiveness of a 2-year pilot SCID NBS program in the Czech Republic, emphasising the utility of combined TREC/KREC screening. METHODS: Between January 2022 and December 2023, a dual TREC/KREC NBS pilot was conducted across the Czech Republic, alongside spinal muscular atrophy (SMA) screening. Approximately 200,000 newborns were screened using quantitative real-time PCR on dried blood spots collected 48-72 h after birth. RESULTS: The pilot referred 58 newborns, identifying 21 cases of IEI, including two SCID cases, with an overall incidence of TREC/KREC screenable IEI of 10.5/100,000 newborns. SCID incidence was 1/100,000. KREC screening proved invaluable, detecting 10 cases of congenital agammaglobulinemia including novel non-XLA forms, which increased the estimated incidence of agammaglobulinemia in the Czech Republic sixfold. Over one-third of low KREC results were linked to maternal immunosuppression. CONCLUSION: The Czech pilot demonstrated the effectiveness of integrated TREC/KREC NBS in detecting both T- and B-cell immunodeficiencies. As of 2024, SCID and SMA screening are included in the nationwide NBS, with KREC screening significantly improving early detection of B-cell disorders.
- MeSH
- agamaglobulinemie diagnóza MeSH
- B-lymfocyty imunologie MeSH
- genetické nemoci vázané na chromozom X MeSH
- lidé MeSH
- novorozenec MeSH
- novorozenecký screening * metody MeSH
- pilotní projekty MeSH
- receptory antigenů T-buněk * genetika MeSH
- těžká kombinovaná imunodeficience * diagnóza genetika epidemiologie MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- novorozenec MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Česká republika MeSH
Bats are the natural reservoirs for a variety of emerging and re-emerging viruses. Among them, rabies virus (genus Lyssavirus, family Rhabdoviridae) is one of the first and most emblematic described in these animals. Since its first description, several new bat lyssaviruses have been regularly identified. In addition to lyssaviruses, other bat rhabdoviruses have also been discovered, including members of the genera Vesiculovirus, Ledantevirus and, more recently, Alphanemrhavirus and Tupavirus. However, the family Rhabdoviridae is one of the most abundant and diverse viral families, with 434 officially recognized species, divided into 5 subfamilies and 56 different genera. The number of rhabdoviruses associated with bats is therefore probably higher than that currently available. In this study, we first developed and validated a combined nested RT-qPCR technique (pan-rhabdo RT-nqPCR) dedicated to the broad detection of animal rhabdoviruses. After validation, this technique was used for a large retrospective screening of archival bat samples (n = 1962), including blood (n = 816), brain (n = 723) and oral swab (n = 423). These samples were collected from various bat species over a 12-year period (2007-2019) in 9 different countries in Europe and Africa. A total of 23 samples (1.2%) from bat species Miniopterus schreibersii, Rhinolophus euryale and Rhinolophus ferrumequinum tested positive for rhabdovirus infection, including 17 (2.1%) blood and 6 (1.4%) oral swab samples, all collected from bats originating from the Mediterranean region. Complete virus genome sequences were obtained by next-generation sequencing for most of the positive samples. Molecular and phylogenetic analysis of these sequences demonstrated that the virus isolates, named Mediterranean bat virus (MBV), were closely related and represented a new species, Mediterranean vesiculovirus, within the genus Vesiculovirus. MBV was more specifically related to other bat vesiculoviruses previously described from China and North America, together clustering into a distinct group of bat viruses within this genus. Interestingly, our results suggest that MBV is widespread, at least in the western part of the Mediterranean region, where it circulates in the blood of several bat species. These results expand the host range and viral diversity of bat vesiculoviruses, and pave the way for further studies to determine the transmission route and dissemination dynamics of these viruses in bat colonies, as well as to assess their potential threat to public health.
- MeSH
- Chiroptera * virologie MeSH
- fylogeneze MeSH
- genom virový MeSH
- infekce viry z čeledi Rhabdoviridae * veterinární epidemiologie virologie MeSH
- kvantitativní polymerázová řetězová reakce MeSH
- Vesiculovirus * genetika izolace a purifikace klasifikace MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Středomoří MeSH
BACKGROUND: The progression and recurrence are the fatal prognostic factors in glioma patients. However, the therapeutic role and potential mechanism of TRAF7 in glioma patients remain largely unknown. METHODS: TRAF7 RNA-seq was analysed with the TCGA and CGGA databases between glioma tissues and normal brain tissues. The expression of TRAF7, cellular senescence and cell cycle arrest pathways in glioma tissues and cell lines was detected by real-time quantitative PCR (RT-qPCR), western blotting and immunohistochemistry. The interaction between TRAF7 and KLF4 was determined by Co-immunoprecipitation (Co-IP) assays. The functions of TRAF7 combined with lomustine in glioma were assessed by both in vitro, in vivo and patient-derived primary and recurrent glioma stem cell (GSC) assays. RESULTS: High TRAF7 expression is closely associated with a higher recurrence rate and poorer overall survival (OS). In vitro, TRAF7 knockdown significantly inhibits glioma cell proliferation, invasion, and migration. RNA-seq analysis revealed that TRAF7 inhibition activates pathways related to cellular senescence and cell cycle arrest. In both in vitro and patient-derived GSC assays, the combination of sh-TRAF7 and lomustine enhanced therapeutic efficacy by inducing senescence and G0/G1 cell cycle arrest, surpassing the effects of lomustine or TRAF7 inhibition alone. Mechanistically, TRAF7 interacts with KLF4, and a rescue assay demonstrated that KLF4 overexpression could reverse the effects of TRAF7 depletion on proliferation and cellular senescence. In vivo, TRAF7 knockdown combined with lomustine treatment effectively suppressed glioma growth. CONCLUSION: TRAF7 could be used as a predictive biomarker and the potential therapeutic target among National Comprehensive Cancer Network (NCCN) treatment guidelines in the progression and recurrence of glioma. Lomustine, regulating cellular senescence and cell cycle could be the priority choice in glioma patients with high-level TRAF7 expression.
- MeSH
- genový knockdown MeSH
- gliom * patologie genetika farmakoterapie metabolismus MeSH
- Krüppel-like faktor 4 MeSH
- lidé MeSH
- lokální recidiva nádoru * genetika patologie MeSH
- lomustin * farmakologie terapeutické užití MeSH
- myši MeSH
- nádorové buněčné linie MeSH
- nádory mozku * patologie genetika farmakoterapie metabolismus MeSH
- peptidy a proteiny asociované s receptory TNF * genetika metabolismus MeSH
- prognóza MeSH
- progrese nemoci MeSH
- proliferace buněk MeSH
- regulace genové exprese u nádorů MeSH
- stárnutí buněk * účinky léků MeSH
- xenogenní modely - testy protinádorové aktivity MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- myši MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
OBJECTIVES: The aim of the study was to evaluate the efficiency of molecular diagnostics of tick-borne encephalitis (TBE) and to correlate viral RNA (vRNA) detection with the clinical and laboratory data. METHODS: Clinical samples from 1125 patients from South Bohemia, Czech Republic, a highly endemic TBE region, were screened for TBE virus (TBEV) RNA by RT-qPCR. Samples included blood, serum, cerebrospinal fluid (CSF), and urine. RESULTS: TBEV RNA was detected in 14 patients with clinically proven TBE. TBEV RNA was most frequently detected in sera during early infection (11/37 patients tested, 29.7%) but decreased with rising IgG antibody response (3/228, 1.3%). Detection in CSF and urine was infrequent (1/30, 3.3% and 1/52, 1.9%, respectively). Additionally, five patients initially not diagnosed with TBE were retrospectively found to have TBEV RNA in serum, indicating possible underdiagnosis, particularly in mild or atypical presentations. The study also highlighted the diagnostic challenge of an immunocompromised patient whose delayed antibody response hindered timely diagnosis. In such cases, RT-qPCR could significantly shorten the diagnostic timeline. CONCLUSIONS: These findings underscore the value of early RNA detection in improving the diagnosis of TBE and may in the future facilitate the early administration of potential treatment, thereby improving patient outcomes.
- MeSH
- diagnostické techniky molekulární metody MeSH
- dítě MeSH
- dospělí MeSH
- imunoglobulin G krev MeSH
- klíšťová encefalitida * diagnóza virologie MeSH
- kvantitativní polymerázová řetězová reakce MeSH
- lidé středního věku MeSH
- lidé MeSH
- mladiství MeSH
- mladý dospělý MeSH
- předškolní dítě MeSH
- protilátky virové krev MeSH
- RNA virová * krev mozkomíšní mok izolace a purifikace MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- viry klíšťové encefalitidy * izolace a purifikace genetika MeSH
- Check Tag
- dítě MeSH
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mladiství MeSH
- mladý dospělý MeSH
- mužské pohlaví MeSH
- předškolní dítě MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Česká republika MeSH
Applications like drug development need simple and streamlined methods to process samples from 96-well cell culture plates for gene expression measurements. Unfortunately, current options are expensive for such processing. Therefore, our aim was to develop a method that would allow streamlined analysis of mRNA from 96-well cell culture plates while being relatively cheap and simple. We developed a method based on the qPCR 'Cells-to-cDNA' approach and validated it against commercially available kits using the same approach or spin columns-based RNA purification. For this purpose, we conducted a series of comparisons of gene expression from peripheral blood mononuclear cells, SK-HEP-1 and U-87 cell cultures in 96-well plates. Our final method involved lysing cells with 25-100 μl solution of 0.5% SDS, 10 mM DTT, 1 mg ml-1 proteinase K dissolved in water, 1 h incubation at 50°C, followed by proteinase K inactivation at 90°C for 5 min and lysate neutralization with 1 : 1 dilution by 20% Tween 20 solution. Reverse transcription and qPCR were carried out using standard methods. This method showed a mean reduction of Ct ± s.d. value by 2.4 ± 1.3 compared with the 'Cells-to-cDNA' kit and by 1.4 ± 0.5 compared with the RNA purification kit with lower variability.
- MeSH
- analýza nákladů a výnosů MeSH
- buněčné kultury metody ekonomika MeSH
- komplementární DNA * genetika MeSH
- kvantitativní polymerázová řetězová reakce metody MeSH
- leukocyty mononukleární cytologie metabolismus MeSH
- lidé MeSH
- messenger RNA genetika metabolismus MeSH
- nádorové buněčné linie MeSH
- stanovení celkové genové exprese metody ekonomika MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
Aging and age-related neurodegenerative disorders are characterized by the dysfunction or loss of brain nicotinic acetylcholine receptors (nAChRs), and these changes may be related to other senescence markers, such as oxidative stress and DNA repair dysfunction. However, the mechanism of nAChR loss in the aging brain and the modification of this process by drugs (e.g., memantine, Mem) are not yet fully understood. To study whether the differences in nAChR expression in the rat brain occur due to aging or oxidative stress and are modulated by Mem, we analyzed nAChR subunits (at RNA and protein levels) and other biomarkers by real-time quantitative polymerase chain reaction (RQ-PCR) and Western blot validation. Twenty-one female Wistar rats were divided into four groups, depending on age, and the oldest group received injections of Mem or water with the use of intragastric catheters. We studied the cerebral grey matter (CGM), subcortical white matter (SCWM), and cerebellum (Ce). Results showed an age-related decrease of α7 nAChR mRNA level in SCWM. The α7 nAChR mRNA loss was accompanied by reduced expression of 8-oxoguanine DNA glycosylase 1 (OGG1) and an increased tumor necrosis factor alpha (TNFα) level. In the water group, we observed a higher level of α7 nAChR protein in the SCWM and Ce. Biomarker levels changed, but to a different extent depending on the brain area. Importantly, the dysfunction in antioxidative status was stopped and even regressed under Mem treatment. After two weeks of treatment, an increase in TP53 protein level and a decrease in 8-oxo-2'deoxyguanosine (8-oxo-2'dG) level were observed. We conclude that Mem administration may be protective against the senescence process by antioxidative mechanisms.
- MeSH
- alfa7 nikotinové acetylcholinové receptory metabolismus genetika MeSH
- DNA-glykosylasy metabolismus genetika MeSH
- krysa rodu rattus MeSH
- memantin * farmakologie MeSH
- mozek * metabolismus účinky léků patologie MeSH
- neurony metabolismus účinky léků MeSH
- nikotinové receptory * metabolismus genetika MeSH
- oxidační stres * účinky léků MeSH
- poškození DNA * účinky léků MeSH
- potkani Wistar * MeSH
- stárnutí * metabolismus MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
AIMS/BACKGROUND: Johanson-Blizzard syndrome (JBS) is a rare autosomal recessive disease caused by pathogenic variants in the UBR1 gene. JBS is usually suspected based on characteristic anomalies, but only genetic testing provides a definitive diagnosis. Since most variants are inherited from the parents, we aimed to identify the causal variants in a Czech proband with clinically suspected JBS and perform segregation analysis. METHODS: A proband with clinically suspected JBS underwent clinical exome sequencing (CES). Sanger sequencing was used for the validation, characterization, and segregation of variants in the family. The variants were also characterized using quantitative real-time PCR (qPCR) and in silico analysis. RESULTS: Using CES in the proband, we identified two novel causal variants in the UBR1 gene, c.3482A>C and c.3509+6T>C. Although the variants were found in trans, neither was detected in the parents. Sanger sequencing of the cDNA revealed that the novel variant c.3509+6T>C caused activation of the non-canonical GC donor splice site. The inclusion of 70 bp of the intronic sequence generated a frameshift and a premature termination codon leading to nonsense-mediated decay, as detected by qPCR. In silico protein structural analysis showed that the novel missense variant c.3482A>C in the zinc-stabilized domain RING-H2 altered a highly conserved zinc-coordinating histidine by proline. CONCLUSION: To the best of our knowledge, we report the first molecular confirmation of JBS in the Czech Republic and the first identification of two de novo causal variants in two alleles. Our findings also expand the spectrum of pathogenic variants in the UBR1 gene.
- MeSH
- anální atrézie * genetika MeSH
- ektodermální dysplazie * genetika MeSH
- hypotyreóza * genetika MeSH
- lidé MeSH
- malabsorpční syndromy * genetika MeSH
- mentální retardace * genetika MeSH
- nemoci slinivky břišní * genetika MeSH
- nos * abnormality abnormality MeSH
- percepční nedoslýchavost * genetika MeSH
- poruchy růstu * genetika MeSH
- rodokmen MeSH
- sekvenování exomu MeSH
- ubikvitinligasy * genetika MeSH
- žlučové kameny * genetika MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- kazuistiky MeSH