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1.
Clin Chem Lab Med ; 2024 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-39311541

RESUMEN

OBJECTIVES: Until now, the external quality assessment (EQA) of glucose point-of-care testing (POCT) has lacked a high quality, suitable and commutable control material to assess measurement accuracy. Here we present a concept for determining the accuracy of glucose measurements, which uses human whole blood and does not require stabilising agents. METHODS: This new generation of quality control samples uses a bead that contains a specific amount of glucose. The bead is then dissolved in a whole blood matrix by the EQA participant immediately before the POCT. We analysed its suitability as an EQA material with respect to its reproducibility, homogeneity and stability, and applied it in an EQA pilot study. The glucose target value was determined using the reference measurement procedure and served as an evaluation criterion for the accuracy of the EQA survey results. RESULTS: The homogeneity and stability of the new control material fulfilled the quality requirements of ISO 17043. Based on the reference measurement value for glucose, the results of the pilot EQA scheme showed a pass rate of 84.6 % for the participating POCT devices. The acceptance limit was a 15 % permitted deviation from the target value according to Rili-BAEK. All of the device collectives deviated from the target value by 0-4.4 % with the exception of one device type, which deviated by 21 %. CONCLUSIONS: The new concept offers, for the first-time, whole blood-based trueness controls for glucose POCT analysis for external quality assurance. The concept does not require the addition of any stabilising reagent and is easy to use.

2.
Int J Mol Sci ; 24(13)2023 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-37445666

RESUMEN

Priming plants with beneficial microbes can establish rapid and robust resistance against numerous pathogens. Here, compelling evidence is provided that the treatment of rapeseed plants with Trichoderma harzianum OMG16 and Bacillus velezensis FZB42 induces defence activation against Verticillium longisporum infection. The relative expressions of the JA biosynthesis genes LOX2 and OPR3, the ET biosynthesis genes ACS2 and ACO4 and the SA biosynthesis and signalling genes ICS1 and PR1 were analysed separately in leaf, stem and root tissues using qRT-PCR. To successfully colonize rapeseed roots, the V. longisporum strain 43 pathogen suppressed the biosynthesis of JA, ET and SA hormones in non-primed plants. Priming led to fast and strong systemic responses of JA, ET and SA biosynthesis and signalling gene expression in each leaf, stem and root tissue. Moreover, the quantification of plant hormones via UHPLC-MS analysis revealed a 1.7- and 2.6-fold increase in endogenous JA and SA in shoots of primed plants, respectively. In roots, endogenous JA and SA levels increased up to 3.9- and 2.3-fold in Vl43-infected primed plants compared to non-primed plants, respectively. Taken together, these data indicate that microbial priming stimulates rapeseed defence responses against Verticillium infection and presumably transduces defence signals from the root to the upper parts of the plant via phytohormone signalling.


Asunto(s)
Brassica napus , Verticillium , Enfermedades de las Plantas/genética , Brassica napus/genética , Brassica napus/metabolismo , Verticillium/fisiología , Reguladores del Crecimiento de las Plantas , Expresión Génica , Hormonas , Regulación de la Expresión Génica de las Plantas , Ciclopentanos/metabolismo , Oxilipinas/metabolismo
3.
Mol Plant Microbe Interact ; 35(5): 380-392, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35147443

RESUMEN

Rhizosphere-competent microbes often interact with plant roots and exhibit beneficial effects on plant performance. Numerous bacterial and fungal isolates are able to prime host plants for fast adaptive responses against pathogen attacks. Combined action of fungi and bacteria may lead to synergisms exceeding effects of single strains. Individual beneficial fungi and bacteria have been extensively studied in Arabidopsis thaliana, but little is known about their concerted actions in the Brassicaceae. Here, an in-vitro system with oilseed rape (Brassica napus) was established. Roots of two different cultivars were inoculated with well-characterized fungal (Trichoderma harzianum OMG16) and bacterial (Bacillus velezensis FZB42) isolates alone or in combination. Microscopic analysis confirmed that OMG16 hyphae entered root hairs through root hair tips and formed distinct intracellular structures. Quantitative PCR revealed that root colonization of OMG16 increased up to 10-fold in the presence of FZB42. Relative transcript levels of the ethylene- and jasmonic acid-responsive genes PDF1.2, ERF2, and AOC3 were recorded in leaves by quantitative reverse transcription PCR to measure induced systemic resistance in tissues distant from the roots. Combined action of OMG16 and FZB42 induced transcript abundances more efficiently than single inoculation. Importantly, microbial priming reduced Verticillium longisporum root infection in rapeseed by approximately 100-fold compared with nonprimed plants. Priming also led to faster and stronger systemic responses of the defense genes PDF1.2, ERF2, AOC3, and VSP2.[Formula: see text] Copyright © 2022 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.


Asunto(s)
Arabidopsis , Ascomicetos , Bacillus , Brassica napus , Brassica rapa , Trichoderma , Verticillium , Arabidopsis/microbiología , Brassica napus/genética , Enfermedades de las Plantas/microbiología , Raíces de Plantas/microbiología , Trichoderma/fisiología , Verticillium/fisiología
4.
Acta Derm Venereol ; 100(10): adv00131, 2020 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-32250439

RESUMEN

Isatis tinctoria L. (woad) has been used in medicine for centuries and has demonstrated anti-inflammatory effects. However, to date, no well-defined extracts with precise analysis of active substances have been developed. The aim of this study was to develop novel extracts of Isatis tinctoria L., and to characterize their active ingredients and anti-inflammatory properties. Various extracts of Isatis tinctoria L. were analysed for their active ingredients, and screened for anti-inflammatory effects using cyclooxygenase-2 activity assays. A petroleum ether extract was found to have the best effects, and was tested in a mouse model of acute allergic contact dermatitis. In the mouse model the petroleum ether extract resulted in significantly reduced ear swelling, oedema and inflammatory cell density. In mouse skin and human keratinocyte cultures, petroleum ether extract inhibited pro-inflammatory cytokine expression. Furthermore, human mast cell degranulation was significantly inhibited in LAD2 cell cultures. In conclusion, novel woad extracts were developed and shown to have anti-inflammatory properties in a contact hypersensitivity animal model and human keratinocytes. The production of such extracts and further characterization of their specific properties will enable determination of their potential dermatological effects in the treatment of inflamed and irritated skin.


Asunto(s)
Antiinflamatorios/uso terapéutico , Dermatitis Alérgica por Contacto/tratamiento farmacológico , Isatis , Fitoterapia , Extractos Vegetales/uso terapéutico , Administración Tópica , Animales , Antiinflamatorios/administración & dosificación , Antiinflamatorios/inmunología , Células Cultivadas , Dermatitis Alérgica por Contacto/inmunología , Fármacos Dermatológicos/administración & dosificación , Fármacos Dermatológicos/inmunología , Fármacos Dermatológicos/uso terapéutico , Modelos Animales de Enfermedad , Oído , Humanos , Interleucina-1beta/antagonistas & inhibidores , Interleucina-1beta/inmunología , Interleucina-33/antagonistas & inhibidores , Interleucina-33/inmunología , Interleucina-6/antagonistas & inhibidores , Interleucina-6/inmunología , Queratinocitos/efectos de los fármacos , Queratinocitos/inmunología , Estabilizadores de Mastocitos/administración & dosificación , Estabilizadores de Mastocitos/inmunología , Estabilizadores de Mastocitos/uso terapéutico , Mastocitos/efectos de los fármacos , Mastocitos/inmunología , Ratones , Extractos Vegetales/administración & dosificación , Extractos Vegetales/farmacología , Piel/efectos de los fármacos , Piel/inmunología , Piel/patología
5.
Plant Dis ; 103(7): 1674-1684, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31095470

RESUMEN

A growing world population requires an increase in the quality and quantity of food production. However, field losses due to biotic stresses are currently estimated to be between 10 and 20% worldwide. The risk of resistance and strict pesticide legislation necessitate innovative agronomical practices to adequately protect crops in the future, such as the identification of new substances with novel modes of action. In the present study, liquid chromatography mass spectrometry was used to characterize Rheum rhabarbarum root extracts that were primarily composed of the stilbenes rhaponticin, desoxyrhaponticin, and resveratrol. Minor components were the flavonoids catechin, epicatechin gallate, and procyanidin B1. Specific polyphenolic mixtures inhibited mycelial growth of several phytopathogenic fungi and oomycetes. Foliar spray applications with fractions containing stilbenes and flavonoids inhibited spore germination of powdery mildew in Hordeum vulgare with indications of synergistic interactions. Formulated extracts led to a significant reduction in the incidence of brown rust in Triticum aestivum under field conditions. Arabidopsis thaliana mutant and quantitative reverse-transcription polymerase chain reaction studies suggested that the stilbenes induce salicylic acid-mediated resistance. Thus, the identified substances of Rheum roots represent an excellent source of antifungal agents that can be used in horticulture and agriculture.


Asunto(s)
Resistencia a la Enfermedad , Hongos , Oomicetos , Extractos Vegetales , Polifenoles , Rheum , Antifúngicos/farmacología , Antiparasitarios/farmacología , Resistencia a la Enfermedad/efectos de los fármacos , Hongos/efectos de los fármacos , Oomicetos/efectos de los fármacos , Extractos Vegetales/farmacología , Raíces de Plantas/química , Polifenoles/farmacología , Rheum/química
6.
Ann Allergy Asthma Immunol ; 121(4): 490-495, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-30025909

RESUMEN

BACKGROUND: Even though allergies are an important health issue, the detected amount of allergen-specific IgE (sIgE) has differed widely between manufacturers in the past, and even as recently as this year. These discrepancies hinder diagnostics and can even impact allergen immunotherapy. OBJECTIVE: The aim of this study was to evaluate the development and status quo of the quality of in vitro diagnostic testing for house dust mites (HDM) and cat epithelium, 2 important indoor allergen sources. METHODS: We analyzed data on the allergen sources European HDM, American HDM, and cat epithelium, which were collected by the Society for Promoting Quality Assurance in Medical Laboratories (INSTAND e.V.) during 7 years as part of External Quality Assessment schemes (EQAs). A pseudoanonymized comparison was made of the semiquantitative data and allergen-class results of the 4 main suppliers of in vitro diagnostic sIgE tests. Coefficients of variation (CV) were determined in order to evaluate interlaboratory comparability. RESULTS: In vitro allergy diagnostic testing for the major allergen sources HDM and cat epithelium still reveals manufacturer-dependent differences. Despite this, a cautious trend was found towards an alignment of the results and interlaboratory comparability, with the exception of 1 supplier. CONCLUSION: Even though these results are promising, future EQAs have to be closely monitored to ensure this positive trend is not just a snapshot.


Asunto(s)
Epitelio/inmunología , Hipersensibilidad/diagnóstico , Inmunoglobulina E/sangre , Juego de Reactivos para Diagnóstico/normas , Contaminación del Aire Interior/efectos adversos , Animales , Gatos/inmunología , Conjuntos de Datos como Asunto , Dermatophagoides farinae/inmunología , Dermatophagoides pteronyssinus/inmunología , Humanos , Variaciones Dependientes del Observador
7.
Front Mol Biosci ; 11: 1390079, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38974321

RESUMEN

Introduction: This study presents a longitudinal analysis of external quality assessment (EQA) results for erythropoietin (EPO) determinations conducted between 2017 and 2022 with a continuously increasing number of participating laboratories. The aim of this work was to evaluate participant performance and methodological aspects. Methods: In each of the eleven EQA surveys, a blinded sample set of lyophilized human serum containing one sample with lower EPO concentrations (L) and one with higher EPO concentrations (H) was sent to the participating laboratories. Results: A total of 1,256 measurements were included. The median (interquartile range) fraction of participants not meeting the criteria of acceptance set at 20% around the robust mean of the respective survey was 9.5% (6.1%-10.7%) (sample L) and 9.1% (5.8%-11.8%) (sample H) but lacked a clear trend in the observed period. Some surveys exhibited unusually high interlaboratory variation, suggesting interfering components in the EQA samples. Different immunological methods and reagent manufacturers also showed variability in measurement outcomes to some extent. Conclusion: These findings highlight the need for continuous quality assessment in EPO measurements to ensure patient safety and identify areas for further research and investigation.

8.
Front Mol Biosci ; 11: 1401619, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38966130

RESUMEN

Background: Tumor markers are established laboratory tools that help to diagnose, estimate prognosis, and monitor the course of cancer. For meaningful decision-making in patient care, it is essential that methods and analytical platforms demonstrate high sensitivity, specificity, precision, and comparability. Regular participation at external quality assessment (EQA) schemes is mandatory for laboratories. Here, a longitudinal evaluation of EQA data was performed to assess the performance of tumor marker assays over time. Methods: Longitudinal data of the cancer antigens (CA) 15-3 (n = 5,492), CA 19-9 (n = 6,802), and CA 125 (n = 5,362) from 14 INSTAND EQAs conducted between 2019 and 2023 were evaluated. A median of 197, 244 and 191 laboratories participated at the EQAs for CA 15-3, CA 19-9 and CA 125, respectively. Data evaluation encompasses intra- and inter-manufacturer specific variations over time, assay precision, and adherence to the EQA limits of ±24% for CA 15-3, ±27% for CA 19-9 and ±36% for CA 125. Results: The study showed median manufacturer-dependent differences of up to 107% for CA 15-3, 99% for CA 125, and even 549% for CA 19-9 between the highest and the lowest methods over the studied period. Regarding the normalized median of all methods, the values of the most deviant methods were 0.42 for CA 15-3, 7.61 for CA 19-9, and 1.82 for CA 125. Intra-manufacturer variability was generally low, with median coefficients of variation (CV) below 10%. As the methods were evaluated according to method-specific consensus values, most participants passed the EQAs within the acceptance criteria. When the criteria were consistently set at 24%, the central 90% of participants passed the EQAs in 78.6%-100% for CA 15-3 (with exception of AX), 89.3%-100% for CA 125, and 64.3%-100% for CA 19-9. Conclusion: While intra-method precision of most analytical platforms is acceptable for all three tumor markers, considerable inter-method variability was observed over the whole studied period demonstrating the necessity for better standardization and harmonization of the methods, development of international reference materials, and comprehensive commutability studies with patient samples.

9.
Front Mol Biosci ; 11: 1345356, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38357630

RESUMEN

As hormonal disorders are linked to several diseases, the accurate quantitation of steroid hormone levels in serum is crucial in order to provide patients with a reliable diagnosis. Mass spectrometry-based methods are regarded as having the highest level of specificity and sensitivity. However, immunoassays are more commonly used in routine diagnostics to measure steroid levels as they are more cost effective and straightforward to conduct. This study analyzes the external quality assessment results for the measurement of testosterone, progesterone and 17ß-estradiol in serum using immunoassays between early 2020 and May 2022. As reference measurement procedures are available for the three steroid hormones, the manufacturer-specific biases were normalized to the reference measurement values. The manufacturer-specific coefficients of variation were predominantly inconspicuous, below 20% for the three hormones when outliers are disregarded, however there were large differences between the various manufacturer collectives. For some collectives, the median bias to the respective reference measurement value was repeatedly greater than ±35%, which is the acceptance limit defined by the German Medical Association. In the case of testosterone and progesterone determination, some collectives tended to consistently over- or underestimate analyte concentrations compared to the reference measurement value, however, for 17ß-estradiol determination, both positive and negative biases were observed. This insufficient level of accuracy suggests that cross-reactivity continues to be a fundamental challenge when antibody detection is used to quantify steroids with a high structural similarity. Distinct improvements in standardization are required to provide accurate analysis and thus, reliable clinical interpretations. The increased accuracy of the AX immunoassay for testosterone measurement, as observed in the INSTAND EQAs between 2020 and 2022, could be the result of a recalibration of the assay and raises hope for further improvement of standardization of immunoassay-based steroid hormone analyses in the coming years.

10.
Front Mol Biosci ; 11: 1401405, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39176390

RESUMEN

Background: C-reactive protein (CRP) is an established serum biomarker for different pathologies such as tissue injury and inflammatory events. One rising area of interest is the incorporation of low concentrations of CRP, so called high-sensitive (hs-) CRP, in the risk assessment and treatment monitoring of cardiovascular diseases (CVDs). Many research projects and the resulting meta-analyses have reported controversial results for the use of hs-CRP, especially in the risk assessment of CVDs. However, since these analyses used different assays to detect hs-CRP, it is important to assess the current level of assay harmonization. Methods: This paper analyzes data from 17 external quality assessment (EQA) surveys for hs-CRP conducted worldwide between 2018 and 2023. Each EQA survey consisted of two blinded samples. In 2020 the sample material changed from pooled serum to single-donor samples. The aim was to assess the current status of assay harmonization by a manufacturer-based approach, taking into consideration the clinical decision limits for hs-CRP risk-stratification of CVDs as well as the scatter of results. Results: Our analyses show that harmonization has increased in recent years from median differences of up to 50% to below 20%, with one exception that showed an increasing bias throughout the observed period. After changing sample materials from pools to single-donor samples, the coefficient of variation decreased to below 10% with one exception. Nevertheless, even these differences in the clinical setting could lead to disparate classification of patients depending on the assay used. Conclusion: While there was a positive trend towards harmonization, meta-analysis of different risk-score publications should stratify their analysis by assay to account for the manufacturer-specific differences observed in this paper. Furthermore, assays are currently traceable to different international standard preparations, which might have a negative impact on future harmonization.

11.
Front Mol Biosci ; 11: 1373114, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38601324

RESUMEN

Background: Quality control (QC), quality assurance, and standardization are crucial for modern diagnostic testing in the field of medical microbiology. The need for efficient QC to ensure accurate laboratory results, treatment, and infection prevention has led to significant efforts in standardizing assay reagents and workflows. External quality assessment (EQA) schemes, like those offered by INSTAND, play a vital role in evaluating in-house and commercial routine diagnostic assays, regarded as mandatory by national and global guidelines. The recent impact of polymerase chain reaction/nucleic acid amplification technology (PCR/NAAT) assays in medical microbiology requires that high-performing assays be distinguished from inadequately performing ones, especially those made by inexperienced suppliers. Objectives: The study assesses the evolving diagnostic performance trends over 2 decades for the detection of EHEC/STEC, Borrelia (B.) burgdorferi, and MRSA/cMRSA. It explores the historical context of assay utilization, participant engagement, and rates of correct results in EQA schemes. The research seeks to identify patterns in assay preferences, participant proficiency, and the challenges encountered in detecting emerging variants or clinical strains. Results: The study highlights the decline in in-house PCR assay usage, the emergence of new diagnostic challenges, and educational aspects within EQA schemes. Specific examples, such as the inclusion, in certain EQA surveys, of EHEC strains carrying stx-2f or B. miyamotoi, highlight the role of EQAs in increasing awareness and diagnostic capabilities. Advancements in MRSA detection, especially through the adoption of commercial assays, demonstrate the impact that technology evolution has had on diagnostic performance. Conclusion: Achieving excellence in diagnostic molecular microbiology involves a multifaceted approach, including well-evaluated assays, careful instrumentation selection, and structured training programs. EQA schemes contribute significantly to this pursuit by providing insights into the evolving diagnostic landscape and identifying areas for improvement in the diagnostic workflow as well as in PCR/NAAT assay design.

12.
FEMS Microbiol Ecol ; 100(2)2024 01 24.
Artículo en Inglés | MEDLINE | ID: mdl-38224956

RESUMEN

Microbiome-based solutions are regarded key for sustainable agroecosystems. However, it is unclear how agricultural practices affect the rhizosphere microbiome, plant-microorganism interactions and crop performance under field conditions. Therefore, we installed root observation windows in a winter wheat field cultivated either under long-term mouldboard plough (MP) or cultivator tillage (CT). Each tillage practice was also compared at two nitrogen (N) fertilization intensities, intensive (recommended N-supply with pesticides/growth regulators) or extensive (reduced N-supply, no fungicides/growth regulators). Shoot biomass, root exudates and rhizosphere metabolites, physiological stress indicators, and gene expression were analyzed together with the rhizosphere microbiome (bacterial/archaeal 16S rRNA gene, fungal ITS amplicon, and shotgun metagenome sequencing) shortly before flowering. Compared to MP, the rhizosphere of CT winter wheat contained more primary and secondary metabolites, especially benzoxazinoid derivatives. Potential copiotrophic and plant-beneficial taxa (e.g. Bacillus, Devosia, and Trichoderma) as well as functional genes (e.g. siderophore production, trehalose synthase, and ACC deaminase) were enriched in the CT rhizosphere, suggesting that tillage affected belowground plant-microorganism interactions. In addition, physiological stress markers were suppressed in CT winter wheat compared to MP. In summary, tillage practice was a major driver of crop performance, root deposits, and rhizosphere microbiome interactions, while the N-fertilization intensity was also relevant, but less important.


Asunto(s)
Bacterias , Triticum , Bacterias/genética , Triticum/microbiología , Rizosfera , Retroalimentación , ARN Ribosómico 16S/genética , Raíces de Plantas/microbiología , Fertilización , Suelo , Microbiología del Suelo
13.
Diagnostics (Basel) ; 13(12)2023 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-37370914

RESUMEN

The glycoproteins alpha-fetoprotein (AFP) and carcinoembryonic antigen (CEA) have long been approved as biomarkers for diagnosing and monitoring tumors. International Reference Preparations (IRPs) have been around since 1975. Nevertheless, manufacturer-dependent differences have been reported, indicating a lack of harmonization. This paper analyzes data from 15 external quality assessment (EQA) surveys conducted worldwide between 2018 and 2022. The aim was to gain insight into the longitudinal development of manufacturer-dependent differences for CEA and AFP. In each survey, participating laboratories received two samples with different tumor marker levels. Inter- and intra-assay variability was analyzed and the mean 80% and 90% of the manufacturer collectives were compared to the evaluation criteria of the German Medical Association (RiliBÄK). The median EQA results for CEA revealed manufacturer-dependent differences between the highest and lowest collective of up to 100%; for AFP, the median differences mostly remained below 40%. The coefficients of variation were predominantly low for both markers. We concluded that the current assays for AFP and CEA detection are better harmonized than previously reported. The assays displayed a good robustness; however, a narrowing of the current assessment limits in EQA schemes could further enhance the quality of laboratory testing.

14.
PLoS One ; 18(4): e0285203, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37115793

RESUMEN

BACKGROUND: In May 2022, the monkeypox virus (MPXV) spread into non-endemic countries and the global community was quick to test the lessons learned from the SARS-CoV-2 pandemic. Due to its symptomatic resemblance to other diseases, like the non-pox virus varicella zoster (chickenpox), polymerase chain reaction methods play an important role in correctly diagnosing the rash-causing pathogen. INSTAND quickly established a new external quality assessment (EQA) scheme for MPXV and orthopoxvirus (OPXV) DNA detection to assess the current performance quality of the laboratory tests. METHODS: We analyzed quantitative and qualitative data of the first German EQA for MPXV and OPXV DNA detection. The survey included one negative and three MPXV-positive samples with different MPX viral loads. The threshold cycle (Ct) or other measures defining the quantification cycle (Cq) were analyzed in an assay-specific manner. A Passing Bablok fit was used to investigate the performance at laboratory level. RESULTS: 141 qualitative datasets were reported by 131 laboratories for MPXV detection and 68 qualitative datasets by 65 laboratories for OPXV detection. More than 96% of the results were correctly identified as negative and more than 97% correctly identified as positive. An analysis of the reported Ct/Cq values showed a large spread of these values of up to 12 Ct/Cq. Nevertheless, there is a good correlation of results for the different MPXV concentrations at laboratory level. Only a few quantitative results in copies/mL were reported (MPXV: N = 5; OPXV: N = 2), but the results correlated well with the concentration differences between the EQA samples, which were to a power of ten each. CONCLUSION: The EQA results show that laboratories performed well in detecting both MPXV and OPXV. However, Ct/Cq values should be interpreted with caution when conclusions are drawn about the viral load as long as metrological traceability is not granted.


Asunto(s)
COVID-19 , Mpox , Orthopoxvirus , Humanos , Monkeypox virus/genética , SARS-CoV-2/genética
15.
J Clin Virol ; 165: 105521, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37302248

RESUMEN

BACKGROUND: European legislation defines as "near-patient testing" (NPT) what is popularly and in other legislations specified as "point-of-care testing" (POCT). Systems intended for NPT/POCT use must be characterized by independence from operator activities during the analytic procedure. However, tools for evaluating this are lacking. We hypothesized that the variability of measurement results obtained from identical samples with a larger number of identical devices by different operators, expressed as the method-specific reproducibility of measurement results reported in External Quality Assessment (EQA) schemes, is an indicator for this characteristic. MATERIALS AND METHODS: Legal frameworks in the EU, the USA and Australia were evaluated about their requirements for NPT/POCT. EQA reproducibility of seven SARS-CoV-2-NAAT systems, all but one designated as "POCT", was calculated from variabilities in Ct values obtained from the respective device types in three different EQA schemes for virus genome detection. RESULTS: A matrix for characterizing test systems based on their technical complexity and the required operator competence was derived from requirements of the European In Vitro Diagnostic Regulation (IVDR) 2017/746. Good EQA reproducibility of the measurement results of the test systems investigated implies that different users in different locations have no recognizable influence on their measurement results. CONCLUSION: The fundamental suitability of test systems for NPT/POCT use according to IVDR can be easily verified using the evaluation matrix presented. EQA reproducibility is a specific characteristic indicating independence from operator activities of NPT/POCT assays. EQA reproducibility of other systems than those investigated here remains to be determined.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , Reproducibilidad de los Resultados , COVID-19/diagnóstico , Sistemas de Atención de Punto , Técnicas de Amplificación de Ácido Nucleico
16.
Lancet Microbe ; 4(7): e552-e562, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37156257

RESUMEN

During an epidemic, individual test results form the basis of epidemiological indicators such as case numbers or incidence. Therefore, the accuracy of measures derived from these indicators depends on the reliability of individual results. In the COVID-19 pandemic, monitoring and evaluating the performance of the unprecedented number of testing facilities in operation, and novel testing systems in use, was urgently needed. External quality assessment (EQA) schemes are unique sources of data reporting on testing performance, and their providers are recognised contacts and support for test facilities (for technical-analytical topics) and health authorities (for planning the monitoring of infection diagnostics). To identify information provided by SARS-CoV-2 genome detection EQA schemes that is relevant for public health microbiology, we reviewed the current literature published in PubMed between January, 2020, and July, 2022. We derived recommendations for EQA providers and their schemes for best practices to monitor pathogen-detection performance in future epidemics. We also showed laboratories, test facilities, and health authorities the information and benefits they can derive from EQA data, and from the non-EQA services of their providers.


Asunto(s)
COVID-19 , Pandemias , Humanos , Reproducibilidad de los Resultados , SARS-CoV-2/genética , COVID-19/diagnóstico , COVID-19/epidemiología , Laboratorios
17.
Sci Rep ; 13(1): 13206, 2023 08 14.
Artículo en Inglés | MEDLINE | ID: mdl-37580353

RESUMEN

The COVID-19 pandemic illustrated the important role of diagnostic tests, including lateral flow tests (LFTs), in identifying patients and their contacts to slow the spread of infections. INSTAND performed external quality assessments (EQA) for SARS-CoV-2 antigen detection with lyophilized and chemically inactivated cell culture supernatant of SARS-CoV-2 infected Vero cells. A pre-study demonstrated the suitability of the material. Participants reported qualitative and/or quantitative antigen results using either LFTs or automated immunoassays for five EQA samples per survey. 711 data sets were reported for LFT detection in three surveys in 2021. This evaluation focused on the analytical sensitivity of different LFTs and automated immunoassays. The inter-laboratory results showed at least 94% correct results for non-variant of concern (VOC) SARS-CoV-2 antigen detection for viral loads of ≥ 4.75 × 106 copies/mL and SARS-CoV-2 negative samples. Up to 85% had success for a non-VOC viral load of ~ 1.60 × 106 copies/mL. A viral load of ~ 1.42 × 107 copies/mL of the Delta VOC was reported positive in > 96% of results. A high specificity was found with almost 100% negative SARS-CoV-2 antigen results for HCoV 229E and HCoV NL63 positive samples. Quantitative results correlated with increasing SARS-CoV-2 viral load but showed a broad scatter. This study shows promising SARS-CoV-2 antigen test performance of the participating laboratories, but further investigations with the now predominant Omicron VOC are needed.


Asunto(s)
COVID-19 , SARS-CoV-2 , Chlorocebus aethiops , Animales , Humanos , Pandemias , Células Vero , COVID-19/diagnóstico , COVID-19/epidemiología , Pruebas Inmunológicas , Sensibilidad y Especificidad
18.
Food Chem ; 374: 131756, 2022 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-34875441

RESUMEN

Common variations of traditional consecutive infusions of mate (Ilex paraguariensis) tea were studied. Effects of tea grinding type and water temperature on the extraction of volatile and non-volatile compounds were elucidated. Extraction behavior was determined mainly by grinding type and to a minor extent by water temperature. The extraction behavior along the series of infusions is mostly driven by the way the water can access and flow through the tea mass. This processes are impaired by the formation of clogging layers which are more intense upon the increasing abundance of tea particles of sufficiently small size and high water temperatures.


Asunto(s)
Ilex paraguariensis , Extractos Vegetales/química , Tés de Hierbas/análisis , Antioxidantes , Calor , Ilex paraguariensis/química
19.
Front Public Health ; 10: 883564, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35558533

RESUMEN

Background: A multi-dimensional model can be a useful tool for estimating the general impact of disease on the different sectors of the healthcare system. We chose the sexually transmitted disease syphilis for our model due to the good quality of reported data in Germany. Methods: The model included gender- and age-stratified incident cases of syphilis (in- and outpatients) provided by a German statutory health insurance company, as well as seroprevalence data on syphilis in first-time blood donors. Age standardized rates were calculated based on the standard German population. The test quality was assessed by extrapolating the number of false-positive and false-negative results based on data from Europe-wide external quality assessment (EQA) schemes. The model analysis was validated with the reported cases and diagnosis-related group (DRG)-statistics from 2010 to 2012. The annual direct and indirect economic burden was estimated based on the outcomes of our model. Results: The standardized results were slightly higher than the results reported between 2010 and 2012. This could be due to an underassessment of cases in Germany or due to limitations of the dataset. The number of estimated inpatients was predicted with an accuracy of 89.8 %. Results from EQA schemes indicated an average sensitivity of 92.8 % and an average specificity of 99.9 % for the recommended sequential testing for syphilis. Based on our model, we estimated a total average minimal annual burden of €20,292,110 for syphilis on the German healthcare system between 2010 and 2012. Conclusions: The linking of claims data, results from EQA schemes, and blood donor surveillance can be a useful tool for assessing the burden of disease on the healthcare system. It can help raise awareness in populations potentially at risk for infectious diseases, demonstrate the need to educate potential risk groups, and may help with predictive cost calculations and planning.


Asunto(s)
Sífilis , Atención a la Salud , Humanos , Pacientes Ambulatorios , Estudios Retrospectivos , Estudios Seroepidemiológicos , Sífilis/diagnóstico , Sífilis/epidemiología
20.
Microorganisms ; 10(9)2022 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-36144319

RESUMEN

The long-term effects of agricultural management such as different fertilization strategies on soil microbiota and soil suppressiveness against plant pathogens are crucial. Therefore, the suppressiveness of soils differing in fertilization history was assessed using two Rhizoctonia solani isolates and their respective host plants (lettuce, sugar beet) in pot experiments. Further, the effects of fertilization history and the pathogen R. solani AG1-IB on the bulk soil, root-associated soil and rhizosphere microbiota of lettuce were analyzed based on amplicon sequencing of the 16S rRNA gene and ITS2 region. Organic fertilization history supported the spread of the soil-borne pathogens compared to long-term mineral fertilization. The fertilization strategy affected bacterial and fungal community composition in the root-associated soil and rhizosphere, respectively, but only the fungal community shifted in response to the inoculated pathogen. The potential plant-beneficial genus Talaromyces was enriched in the rhizosphere by organic fertilization and presence of the pathogen. Moreover, increased expression levels of defense-related genes in shoots of lettuce were observed in the soil with organic fertilization history, both in the absence and presence of the pathogen. This may reflect the enrichment of potential plant-beneficial microorganisms in the rhizosphere, but also pathogen infestation. However, enhanced defense responses resulted in retarded plant growth in the presence of R. solani (plant growth/defense tradeoff).

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