qualitative detection
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PLoS ONE ◽  
2022 ◽  
Vol 17 (1) ◽  
pp. e0262258
Author(s):  
Ralph-Sydney Mboumba Bouassa ◽  
Serge Tonen-Wolyec ◽  
David Veyer ◽  
Hélène Péré ◽  
Laurent Bélec

Although patients infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), influenza A, influenza B and respiratory syncytial virus (RSV) show comparable or very similar manifestations, the therapeutic approaches of these respiratory viral infections are different, which requires an accurate diagnosis. Recently, the novel multiplex real-time reverse transcription-polymerase chain reaction assay AMPLIQUICK® Respiratory Triplex (BioSynex SA, Illkirch-Graffenstaden, France) allows simultaneous detection and differentiation of SARS-CoV-2, influenza A, influenza B, and RSV in respiratory tract samples. We herein evaluated the performance of the AMPLIQUICK® Respiratory Triplex for the detection of the four viruses in respiratory specimens, using Allplex™ Respiratory Panel 1 and 2019-nCoV assays (Seegene, Seoul, Korea) as reference comparator assays. A total of 359 archived predetermined respiratory samples, including 83, 145, 19 and 95 positive specimens for SARS-CoV-2, influenza A, influenza B and RSV respectively, were included. The AMPLIQUICK® Respiratory Triplex showed high concordance with the reference assays, with an overall agreement for SARS-CoV-2, influenza A, influenza B, and RSV at 97.6%, 98.8%, 98.3% and 100.0%, respectively, and high κ values ranging from 0.93 to 1.00, indicating an almost perfect agreement between assays. Furthermore, high correlations of cycle threshold (Ct) values were observed for positive samples of the four viruses between the AMPLIQUICK® Respiratory Triplex and comparator assays, with an overall high agreement between Ct values assessed by Bland-Altman analyses. In conclusion, these observations demonstrate that the multiplex AMPLIQUICK® Respiratory Triplex is a reliable assay for the qualitative detection and differentiation of SARS-CoV-2, influenza A, influenza B, and RSV in respiratory specimens, which may prove useful for streamlining diagnostics during the winter influenza-seasons.


2022 ◽  
Author(s):  
Tung Phan ◽  
Stephanie Boes ◽  
Melissa McCullough ◽  
Jamie Gribschaw ◽  
Alan Wells

A new SARS-CoV-2 Omicron (B.1.1.529) Variant of Concern has been emerging worldwide. We are seeing an unprecedented surge in patients due to Omicron in this COVID-19 pandemic. A rapid and accurate molecular test that effectively differentiates Omicron from other SARS-CoV-2 variants would be important for both epidemiologic value and for directing variant-specific therapies such as monoclonal antibody infusions. In this study, we developed a real-time RT-PCR assay for the qualitative detection of Omicron from routine clinical specimens sampling the upper respiratory tract. The limit of detection of the SARS-CoV-2 Omicron variant RT-PCR assay was 2 copies/μl. Notably, the assay did not show any cross-reactivity with other SARS-CoV-2 variants including Delta (B.1.617.2). This SARS-CoV-2 Omicron variant RT-PCR laboratory-developed assay is sensitive and specific to detect Omicron in nasopharyngeal and nasal swab specimens.


2021 ◽  
Author(s):  
Tung Phan ◽  
Ashley Mays ◽  
Melissa McCullough ◽  
Alan Wells

Accurate and rapid laboratory tests are essential for the prompt diagnosis of COVID-19, which is important to patients and infection control. The Xpert Xpress SARS-CoV-2 test is a real-time RT-PCR intended for the qualitative detection of nucleic acid from SARS-CoV-2 in upper respiratory specimens. In this study, we assessed the analytical and clinical performance characteristics of this rapid test for SARS-CoV-2 in 60 bronchoalveolar lavage (BAL) specimens. BAL is a specimen type that is not authorized under EUA for the Xpert Xpress SARS-CoV-2 test. The limit of detection of the Xpert Xpress SARS-CoV-2 test was 500 copies/ml. The overall agreement of the Xpert Xpress SARS-CoV-2 test was 100%. The Xpert Xpress SARS-CoV-2 test is sensitive and specific to aid in diagnosis of COVID-19 using bronchoalveolar lavage.


Metabolomics ◽  
2021 ◽  
Vol 18 (1) ◽  
Author(s):  
Ivayla Roberts ◽  
Marina Wright Muelas ◽  
Joseph M. Taylor ◽  
Andrew S. Davison ◽  
Yun Xu ◽  
...  

Abstract Introduction The diagnosis of COVID-19 is normally based on the qualitative detection of viral nucleic acid sequences. Properties of the host response are not measured but are key in determining outcome. Although metabolic profiles are well suited to capture host state, most metabolomics studies are either underpowered, measure only a restricted subset of metabolites, compare infected individuals against uninfected control cohorts that are not suitably matched, or do not provide a compact predictive model. Objectives Here we provide a well-powered, untargeted metabolomics assessment of 120 COVID-19 patient samples acquired at hospital admission. The study aims to predict the patient’s infection severity (i.e., mild or severe) and potential outcome (i.e., discharged or deceased). Methods High resolution untargeted UHPLC-MS/MS analysis was performed on patient serum using both positive and negative ionization modes. A subset of 20 intermediary metabolites predictive of severity or outcome were selected based on univariate statistical significance and a multiple predictor Bayesian logistic regression model was created. Results The predictors were selected for their relevant biological function and include deoxycytidine and ureidopropionate (indirectly reflecting viral load), kynurenine (reflecting host inflammatory response), and multiple short chain acylcarnitines (energy metabolism) among others. Currently, this approach predicts outcome and severity with a Monte Carlo cross validated area under the ROC curve of 0.792 (SD 0.09) and 0.793 (SD 0.08), respectively. A blind validation study on an additional 90 patients predicted outcome and severity at ROC AUC of 0.83 (CI 0.74–0.91) and 0.76 (CI 0.67–0.86). Conclusion Prognostic tests based on the markers discussed in this paper could allow improvement in the planning of COVID-19 patient treatment.


2021 ◽  
Author(s):  
Jingwei Yang ◽  
Yikang Wang ◽  
Chong Li ◽  
Wei Han ◽  
Weiwei Liu ◽  
...  

Background: Pronuclear assessment appears to have the ability to distinguish good and bad embryos in the zygote stage,but paradoxical results were obtained in clinical studies.This situation might be caused by the robust qualitative detection of the development of dynamic pronuclei. Here,we aim to establish a quantitative pronuclear measurement method by applying expert experience deep learning from large annotated datasets. Methods: Convinced handle-annotated 2PN images(13419) were used for deep learning then corresponded errors were recorded through handle check for subsequent parameters adjusting. We used 790 embryos with 52479 PN images from 155 patients for analysis the area of pronuclei and the preimplantation genetic test results.Establishment of the exponential fitting equation and the key coefficient β1 was extracted from the model for quantitative analysis for pronuclear(PN) annotation and automatic recognition. Findings: Based on the female original PN coefficient β1,the chromosome normal rate in the blastocyst with biggest PN area is much higher than that of the blastocyst with smallest PN area(58.06% vs.45.16%, OR=1.68[1.07-2.64];P=0.031).After adjusting coefficient β1 by the first three frames which high variance of outlier PN areas was removed, coefficient β1 at 12 hours and at 14 hours post-insemination,similar but stronger evidence was obtained. All these discrepancies resulted from the female propositus in the PGT(SR) subgroup and smaller chromosomal errors. Conclusion(s): The results suggest that detailed analysis of the images of embryos could improve our understanding of developmental biology. Funding: None


2021 ◽  
Author(s):  
Nicolò Fabbri ◽  
Antonio Pesce ◽  
Alessandro Ussia ◽  
Francesco D’Urbano ◽  
Stefano Pizzicotti ◽  
...  

Abstract Background. The contamination of body fluids by Severe Acute Respiratory Syndrome Coronavirus 2 during surgery is current matter of debate in the scientific literature concerning CoronaVIrus Disease 2019. Surgical guidelines were published during the first wave of the COVID-19 pandemic and recommended to avoid laparoscopic surgery as much as possible, in fear that the chimney effect of high flow intraperitoneal gas escape during, and after, the procedure would increase the risk of viral transmission.Aim. The aim of this study was to evaluate the possibility of SARS-CoV-2 transmission during surgery by searching for viral RNA in serial samplings of biological liquids.Methods. This is a single center prospective cross-sectional study. We used a real-time reverse transcriptase (RT) polymerase chain reaction (PCR) test to perform swab tests for the qualitative detection of nucleic acid from SARS-CoV-2 in abdominal fluids, during emergency surgery and on the first post-operative day. In the case of thoracic surgery, we performed a swab test of pleural fluids during chest drainage placement as well as on the first post-operative day. Results. A total of 20 samples were obtained: 5 from pleural fluids, 13 from peritoneal fluids and two from biliary fluid. All 20 swabs performed from biological fluids resulted negative for SARS-CoV-2 RNA detection.Conclusion. To date, there is no scientific evidence of possible contagion by laparoscopic aerosolization of SARS-CoV-2, neither is certain whether the virus is effectively present in biological fluids.


Author(s):  
Felicitas Wagener ◽  
Sven Guddat ◽  
Christian Görgens ◽  
Yiannis S. Angelis ◽  
Michael Petrou ◽  
...  

AbstractLGD-4033 (ligandrol) is a selective androgen receptor modulator (SARM), which is prohibited in sports by the World Anti-Doping Agency (WADA) and led to 62 adverse analytical findings (AAFs) in 2019. But not only deliberate doping with LGD-4033 constitutes a problem. In the past years, some AAFs that concerned SARMs can be attributed to contaminated dietary supplements (DS). Thus, the urgency to develop methods to differentiate between inadvertent doping and abuse of SARMs to benefit from the performance-enhancing effect of the compound in sports is growing. To gain a better understanding of the metabolism and excretion patterns of LGD-4033, human micro-dose excretion studies at 1, 10, and 50 µg LGD-4033 were conducted. Collected urine samples were prepared for analysis using enzymatic hydrolysis followed by solid-phase extraction and analyzed via LC-HRMS/MS. Including isomers, a total of 15 phase I metabolites were detected in the urine samples. The LC-HRMS/MS method was validated for qualitative detection of LGD-4033, allowing for a limit of detection (LOD) of 8 pg/mL. The metabolite M1, representing the epimer of LGD-4033, was synthesized and the structure elucidated by NMR spectroscopy. As the M1/LGD-4033 ratio changes over time, the ratio and the approximate LGD-4033 concentration can contribute to estimating the time point of drug intake and dose of LGD-4033 in doping control urine samples, which is particularly relevant in anti-doping result management. Graphical abstract


Author(s):  
Heimo Lagler ◽  
Christine Bangert ◽  
Tamara Quint ◽  
Zoe Österreicher ◽  
Alina Nussbaumer-Pröll ◽  
...  

Abstract There is evidence that Staphylococcus aureus colonisation is linked to severity of atopic dermatitis. As no gold standard for S. aureus sampling on atopic dermatitis skin lesions exists, this study compared three commonly used methods. In addition, effectiveness of standard skin disinfection to remove S. aureus colonisation from these inflamed skin lesions was investigated. In 30 atopic dermatitis patients, three different S. aureus sampling methods, i.e. detergent scrubbing, moist swabbing and tape stripping, were performed on naïve and disinfected skin lesions. Two different S. aureus selective media, mannitol salt agar and chromID agar, were used for bacterial growing. Quantifying the S. aureus load varied significantly between the different sampling methods on naïve skin lesions ranging from mean 51 to 1.5 × 104 CFU/cm2 (p < 0.001). The qualitative detection on naïve skin was highest with the two detergent-based techniques (86% each), while for tape stripping, this value was 67% (all on chromID agar). In comparison, mannitol salt agar was less sensitive (p < 0.001). The disinfection of the skin lesions led to a significant reduction of the S. aureus load (p < 0.05) but no complete eradication in the case of previously positive swab. The obtained data highlight the importance of the selected sampling method and consecutive S. aureus selection agar plates to implement further clinical studies for the effectiveness of topical anti-staphylococcal antibiotics. Other disinfection regimes should be considered in atopic dermatitis patients when complete de-colonisation of certain skin areas is required, e.g. for surgical procedures.


Author(s):  
Rawaa Al-Kayali ◽  
Joud Jalab ◽  
Adawia Kitaz ◽  
Wassim Abdelwahed

Background Acacia cyanophylla is a medicinal plant of the Fabaceae family that is widely distributed in Australia and Asia, also it has many medicinal properties such as antibacterial and antioxidant activity. Thin layer chromatography (TLC) is wildly used in natural product extract analysis as a finger print. Aim and objective: This study is aimed to conducting a qualitative detection of the active compounds in Acacia cyanophylla, Phlomis syriaca and Scolymus hispanicus plants by thin layer chromatography (TLC) method and studying their antibacterial activity. Methods: the qualitative detection of three plants was conducting using thin layer chromatography (TLC) method. Then, aqueous and ethanolic extracts of the aerial parts of the three plants were extracted using an Ultrasonic bath.  The antibacterial activity on E. coli isolates for six extracts was evaluated using minimum inhibitory concentration (MIC) test. The active compounds that may be responsible for the antibacterial effect was isolated by direct bioautograph method. Results: Performing Thin-layer chromatography TLC tests show  that the three plant contain flavonoids, saponin, bitter principles and essential oils, and all extracts showed antibacterial activity on E. coli isolates, but the ethanolic extract of Acacia cyanophylla was the most effective as the MIC values ranged from 0.097to 3.125mg/mL. Bioautography showed that Escherichia coli was inhibited by most of the separated flavonoids on the TLC plates where four inhibiting spots appeared in yellow color with Acacia cyanophylla and five spots with Scolymus hispanicus, while only one spot appeared with Phlomis syriaca. Conclusion: Acacia cyanophylla extract has been considered as the best antibacterial properties among the selected plants due to the presence of flavonoids                    Peer Review History: Received: 19 July 2021; Revised: 7 August; Accepted: 2 September, Available online: 15 September 2021 Academic Editor:  Ahmad Najib, Universitas Muslim Indonesia, Makassar, Indonesia, [email protected] UJPR follows the most transparent and toughest ‘Advanced OPEN peer review’ system. The identity of the authors and, reviewers will be known to each other. This transparent process will help to eradicate any possible malicious/purposeful interference by any person (publishing staff, reviewer, editor, author, etc) during peer review. As a result of this unique system, all reviewers will get their due recognition and respect, once their names are published in the papers. We expect that, by publishing peer review reports with published papers, will be helpful to many authors for drafting their article according to the specifications. Auhors will remove any error of their article and they will improve their article(s) according to the previous reports displayed with published article(s). The main purpose of it is ‘to improve the quality of a candidate manuscript’. Our reviewers check the ‘strength and weakness of a manuscript honestly’. There will increase in the perfection, and transparency.  Received file:                Reviewer's Comments: Average Peer review marks at initial stage: 6.0/10 Average Peer review marks at publication stage: 7.0/10 Reviewers: Dr. Sangeetha Arullappan, Universiti Tunku Abdul Rahman, Malaysia, [email protected] Taha A.I. El Bassossy, Medicinal and Aromatic Plants Department, Desert Research Center, Cairo, Egypt, [email protected] Similar Articles: EVALUATION OF ANTIBACTERIAL RESISTANCE OF BIOFILM FORMS OF AVIAN SALMONELLA GALLINARUM TO FLUOROQUINOLONES


Author(s):  
Michele D Tisdale ◽  
David R Tribble ◽  
Indrani Mitra ◽  
Kalyani Telu ◽  
Huai-Ching Kuo ◽  
...  

Abstract Background: We assessed the compliance with self-collection of stool smears on Whatman® FTA® Elute Card (FTA Card) and detection of travelers’ diarrhea (TD) associated pathogens using a quantitative PCR assay (customized TaqMan® array card [TAC]), in a prospective, observational cohort of travelers. Methods: Enrolled travelers documented symptoms on a travel diary and collected an FTA Card during a diarrheal episode, or at the end of travel if they remained asymptomatic. TAC testing was performed on FTA Cards from TD cases and 1:1 matched asymptomatic controls and 1:1 matched loose stool cases that did not meet TD criteria. Odds ratios (OR) were used to determine the association between detected pathogens and TD. Results: 484 of 2456 (19.7%) travelers completed an illness diary and met TD criteria, and 257 (53.1%) collected an FTA Card during the TD episode. FTA Cards were stored for a median of 2 years at room temperature (IQR: 1-4 years) before extraction and testing. The overall TAC detection rate in TD cases was 58.8% (95%CI: 52.5-64.8). Enterotoxigenic E. coli was the most common pathogen in TD cases (26.8%) and 3.5% of samples were positive for norovirus. The odds of detecting TD-associated pathogens in 231 matched cases and asymptomatic controls was 5.4 (95% CI: 3.6-8.1) and 2.0 (95% CI:1.1-3.7) in 121 matched TD and loose stool cases (p &lt; 0.05). Enteroaggregative E coli was the most common pathogen detected in asymptomatic controls and loose stool cases. Detection of diarrheagenic E coli, Shigella/enteroinvasive E coli (EIEC), and Campylobacter spp. was significantly associated with TD. Conclusions: FTA Cards are a useful adjunct to traditional stool collection methods for evaluating the pathogen-specific epidemiology of TD in austere environments. Qualitative detection of pathogens was associated with TD. Measures to improve compliance and quality of FTA Card collection with decreased storage duration may further optimize detection.


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