PCR amplification
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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
In this study, lactic acid bacteria (LAB) isolation from fermented foods and molecular identification using magnetic bead technology were performed. And then exopolysaccharide (EPS) production possibility was tested in agar medium, and the positive ones were selected for the next step. The bacteria that could produce higher carbohydrate level were grown in MRS medium fortified with whey and pumpkin waste. In our study, 19 different LAB species were identified from fermented products collected from different places in Hatay (Türkiye) province. In molecular identification, universal primer pairs, p806R/p8FPL, and PEU7/DG74 were used for PCR amplification. After that, PCR products purified using paramagnetic bead technology were sequenced by the Sanger sequencing method. The dominant species, 23.8% of the isolates, were identified as Lactiplantibacillus plantarum. As a technological property of LAB, exopolysaccharide production capability of forty-two LAB isolate was tested in agar medium, and after eleven isolates were selected as positive. Two LAB (Latilactobacillus curvatus SHA2-3B and Loigolactobacillus coryniformis SHA6-3B) had higher EPS production capability when they were grown in MRS broth fortified with pumpkin waste and whey. The highest EPS content (1750 mg/L glucose equivalent) was determined in Loigolactobacillus coryniformis SHA6-3B grown in MRS broth fortified with 10% pumpkin waste. Besides the produced EPS samples were validated with FTIR and SEM methods.
- MeSH
- bakteriální polysacharidy * biosyntéza metabolismus MeSH
- Cucurbita mikrobiologie MeSH
- fermentace MeSH
- fermentované potraviny * mikrobiologie MeSH
- fylogeneze MeSH
- kultivační média chemie MeSH
- Lactobacillales * izolace a purifikace klasifikace genetika metabolismus MeSH
- odpadní produkty * analýza MeSH
- potravinářská mikrobiologie * MeSH
- RNA ribozomální 16S genetika MeSH
- syrovátka MeSH
- Publikační typ
- časopisecké články MeSH
Androgen deprivation therapy has long been the first-line treatment for hormone-sensitive prostate cancer (HSPC). After progression to castration-resistant prostate cancer (CRPC), androgen receptor pathway inhibitors (ARPIs) are commonly used. Recently, combined therapy with androgen deprivation and an ARPI has been recommended for metastatic HSPC patients. Novel markers are urgently needed for monitoring this disease and for making therapeutic decisions. Plasma samples were collected from 140 patients with either metastatic HSPC (n = 72) or CRPC (n = 68) before the start of ARPI therapy. Digital PCR was used to assess AR gene amplification, while the expression levels of miR-375 were measured by quantitative PCR. Sixteen other clinical markers were also evaluated, including prostate-specific antigen (PSA), chromogranin A (CGA), alkaline phosphatase (ALP), lactate dehydrogenase (LDH), C-reactive protein (CRP), lymphocyte-to-monocyte ratio, and platelet count. A multivariate analysis, adjusted for age and metastatic dissemination, identified miR-375 expression and lymphocyte-to-monocyte ratio to be the independent negative predictors of ARPI therapy failure in CRPC patients. Regarding the HSPC patients, this article reports the primary finding of the independent negative predictive value of platelet count, CRP, and CGA for the failure of combined androgen deprivation therapy and ARPI.
- MeSH
- androgenní receptory genetika MeSH
- C-reaktivní protein * metabolismus MeSH
- chromogranin A * krev MeSH
- lidé středního věku MeSH
- lidé MeSH
- metastázy nádorů MeSH
- mikro RNA * genetika krev MeSH
- nádorové biomarkery krev MeSH
- nádory prostaty rezistentní na kastraci * krev genetika patologie farmakoterapie diagnóza MeSH
- neúspěšná terapie MeSH
- prognóza MeSH
- prostatický specifický antigen * krev MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- trombocyty * metabolismus MeSH
- Check Tag
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- Publikační typ
- časopisecké články MeSH
Background: Stenotrophomonas infections are becoming more widespread around the world and can be counted as a "newly emerging pathogen of concern". The present study aimed to detect a variety of Stenotrophomonas species (S. maltophilia) using specific 23S rRNA gene primers and investigate their multi-drug resistance potential.Methods: This study includes 375 clinical samples from different clinical sources 175 from males and 200 from females collected from Mosul City Hospital. Identification of Stenotrophomonas was conducted through multiple steps including culturing methods, molecular methods in addition to some biochemical tests 11(3%) of isolates belonged to Stenotrophomonas maltophilia. The isolates understudy were tested for their ability to resist 10 different antibiotics using the Kirby-Bauer disk diffusion method.Results: The resistance rate to amoxicillin, gentamicin, and amikacin (100%), cefixime (91%), imipenem (64%), meropenem(55%), Azithromycin (36%), nalidixic acid and trimethoprim (18%), ciprofloxacin(0%). The virulence factors of S. maltophilia siderophores were found in all (11) isolates belonging to S. maltophilia at a percentage (100%). The result of PCR assay using specific primers designed for detecting 23S rRNA genes of S. maltophilia gives amplification for 11 isolates from 14 suspected isolates. Nucleic acid sequencing for the 23S rRNA gene shows that all isolates belong to S. maltophilia with a similarity rate (91-99) in NCBI.Because the 23S rRNA gene sequence in Stenotrophomonas species shows more variety in this location this study used specific 23S rRNA gene primers to identify S. maltophilia.Conclusion: The study used phenotypic and molecular diagnostic techniques to isolate the bacteria, including the S rRNA23 gene. The results emphasize the need for increased vigilance in hospitals to prevent the spread of antibiotic-resistant bacteria and the development of new treatment strategies.
- MeSH
- antibiotická rezistence genetika MeSH
- bakteriální léková rezistence genetika MeSH
- infekce spojené se zdravotní péčí genetika mikrobiologie MeSH
- klinická studie jako téma metody MeSH
- lidé MeSH
- mikrobiologické techniky metody MeSH
- polymerázová řetězová reakce metody MeSH
- RNA ribozomální 23S * analýza genetika MeSH
- siderofory analýza genetika MeSH
- Stenotrophomonas maltophilia * genetika patogenita MeSH
- Check Tag
- lidé MeSH
We designed and synthesized a set of four 2'-deoxyribonucleoside 5'-O-triphosphates (dNTPs) bearing cationic substituents (protonated amino, methylamino, dimethylamino and trimethylammonium groups) attached to position 5 of pyrimidines or position 7 of 7-deazapurines through hex-1-ynyl or propargyl linker. These cationic dNTPs were studied as substrates in enzymatic synthesis of modified and hypermodified DNA using KOD XL DNA polymerase. In primer extension (PEX), we successfully obtained DNA containing one, two, three, or (all) four modified nucleotides, each bearing a different cationic modification. The cationic dNTPs were somewhat worse substrates compared to previously studied dNTPs bearing hydrophobic or anionic modifications, but the polymerase was still able to synthesize sequences up to 73 modified nucleotides. We also successfully combined one cationic modification with one anionic and two hydrophobic modifications in PEX. In polymerase chain reaction (PCR), we observed exponential amplification only in the case of one cationic modification, while the combination of more cationic nucleotides gave either very low amplification or no PCR product. The hypermodified oligonucleotides prepared by PEX were successfully re-PCRed and sequenced by Sanger sequencing. Biophysical studies of hybridization, denaturation, and circular dichroism spectroscopy showed that the presence of cationic modifications increases the stability of duplexes.
In less than a decade, immune checkpoint inhibitors (ICIs) have transformed the management of mismatch repair-deficient (dMMR) and microsatellite instability-high (MSI) cancers. However, beyond colorectal cancer (CRC), much of the evidence is mostly derived from non-randomized phase II studies or post-hoc analyses of broader clinical trials. dMMR/MSI tumours represent a specific subgroup of gastro-esophageal adenocarcinomas (GEA), accounting for approximately 9 % of cases, with a higher prevalence in early-stage compared to advanced-stage disease and older female patients. These tumours are predominantly sporadic, often linked to MLH1 promoter methylation, and rarely exhibit HER2 overexpression/ERBB2 amplification or other oncogenic drivers. The treatment landscape for early stage dMMR/MSI GEA is likely to change substantially soon, as ICIs have shown high pathological complete response (pCR) rates in small phase II trials, raising questions on optimisation of neoadjuvant therapy, and paving the way for organ preservation. The standard of treatment for untreated patients with advanced dMMR/MSI GEA is chemotherapy + ICI irrespectively of PDL-1 status. However, the role of chemotherapy-free regimen consisting of CTLA-4 plus PD-1 inhibitors remains undetermined. This review addresses these and other emerging questions, offering expert opinions and insights into the future therapeutic landscape for dMMR/MSI GEA.
- MeSH
- adenokarcinom * farmakoterapie genetika patologie terapie MeSH
- inhibitory kontrolních bodů terapeutické užití MeSH
- lidé MeSH
- mikrosatelitní nestabilita * MeSH
- nádory jícnu * farmakoterapie genetika patologie MeSH
- nádory žaludku * farmakoterapie genetika patologie terapie MeSH
- oprava chybného párování bází DNA * MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
BACKGROUND: Obesity plays a crucial role in the development of metabolic disorders including diabetes, coronary and renal diseases. There are several factors involved in the pathology of obesity, including chronic inflammation and exposure to environmental contaminants. Recently, the cholinergic co-hydrolyzing enzyme BChE has been associated with clinical conditions such as diabetes and obesity. This study aims to investigate the levels of BChE and inflammatory markers in the serum, as well as the association between two specific BCHE gene variants (rs1803274 and rs3495) and the risk of obesity in the Pakistani population. METHODS: The study recruited 350 people with obesity and 200 volunteers with no obesity. Proinflammatory cytokines (TNF-α, IL-6, and IL-1β) levels were quantified using ELISA kits, while the analysis of BCHE gene SNPs rs1803274 (K-variant) and rs3495 was conducted using the tetra-primer amplification refractory mutation-PCR (tetra-ARM-PCR) and PCR-restriction fragment length polymorphism (RFLP) methods, respectively. Additionally, clinico-pathological parameters HDL, LDL, BMI, Homa-IR, insulin, glucose, blood pressure was also assessed in subjects of current study. RESULTS: Results showed significantly higher levels of BChE, TNF-α, IL-1β, and IL-6 in the obesity group compared to the group without obesity. Furthermore, the obesity group exhibited higher blood pressure and LDL levels, as well as lower HDL levels when compared to group without obesity. Logistic regression analysis revealed a relationship between obesity and higher BChE activity, blood pressure, LDL, and lower HDL levels. The study also found a statistically significant association between the BCHE gene SNPs rs1803274 (K-variant) and rs3495 and the risk of obesity (OR = 2.01; CI = 1.21-3.33; p = 0.0063; OR = 1.80; CI = 1.09-2.96, respectively). CONCLUSIONS: In conclusion, the study suggests that BChE and inflammatory cytokines play a significant role in the development and pathogenesis of obesity and can also act as good diagnostic biomarkers for obesity and its related metabolic disorders.
- MeSH
- butyrylcholinesterasa * genetika krev MeSH
- dospělí MeSH
- genetická predispozice k nemoci MeSH
- jednonukleotidový polymorfismus * genetika MeSH
- lidé středního věku MeSH
- lidé MeSH
- obezita * genetika epidemiologie krev MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Pákistán MeSH
Quantitative genomic mapping of DNA damage may provide insights into the underlying mechanisms of damage and repair. Sequencing based approaches are bound to the limitations of PCR amplification bias and read length which hamper both the accurate quantitation of damage events and the ability to map them to structurally complex genomic regions. Optical Genome mapping in arrays of parallel nanochannels allows physical extension and genetic profiling of millions of long genomic DNA fragments, and has matured to clinical utility for characterization of complex structural aberrations in cancer genomes. Here we present a new mapping modality, Repair-Assisted Damage Detection - Optical Genome Mapping (RADD-OGM), a method for single-molecule level mapping of DNA damage on a genome-wide scale. Leveraging ultra-long reads to assemble the complex structure of a sarcoma cell-line genome, we mapped the genomic distribution of oxidative DNA damage, identifying regions more susceptible to DNA oxidation. We also investigated DNA repair by allowing cells to repair chemically induced DNA damage, pinpointing locations of concentrated repair activity, and highlighting variations in repair efficiency. Our results showcase the potential of the method for toxicogenomic studies, mapping the effect of DNA damaging agents such as drugs and radiation, as well as following specific DNA repair pathways by selective induction of DNA damage. The facile integration with optical genome mapping enables performing such analyses even in highly rearranged genomes such as those common in many cancers, a challenging task for sequencing-based approaches.
- MeSH
- bromičnany toxicita MeSH
- lidé MeSH
- mapování chromozomů * přístrojové vybavení metody MeSH
- mikrofluidní analytické techniky * přístrojové vybavení metody MeSH
- nádorové buněčné linie MeSH
- nanotechnologie * přístrojové vybavení metody MeSH
- oprava DNA genetika MeSH
- oxidační stres účinky léků genetika MeSH
- poškození DNA * genetika MeSH
- regulace genové exprese MeSH
- stanovení celkové genové exprese MeSH
- toxikogenetika * přístrojové vybavení metody MeSH
- variabilita počtu kopií segmentů DNA MeSH
- zobrazení jednotlivé molekuly * přístrojové vybavení metody MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
