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1.
J Virol Methods ; 327: 114937, 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38614281

RESUMO

Quantification of hepatitis C virus (HCV)-RNA in serum or plasma samples is an essential parameter in HCV diagnostics. Here, the NeuMoDx™Molecular System (Qiagen) was tested for the most common HCV genotypes and compared to the cobas c6800 system (Roche). HCV-RNA from 131 plasma/serum samples from chronically infected patients was determined in parallel on the NeuMoDx and c6800 systems. Linearity was analysed using the four most common HCV genotypes (1-4) in our cohort. The coefficient of variation (CV) within (intra-assay) and between (inter-assay) runs was calculated based on HCV-RNA concentration. Quantitative HCV-RNA results were highly correlated on both test systems (R2 = 0.7947; y = 0.94 x + 0.37). On average, the NeuMoDx and c6800 HCV RNA levels showed a mean difference of only 0.05 log10 IU/mL but with a broad distribution (±1.2 2 x SD). The NeuMoDx demonstrated very good linearity across all HCV genotypes tested at concentrations between 1.7 and 6.2 log10 IU/mL (R2 range: 0.9257-0.9991) with the highest mean coefficient of determination for genotype 1 (R2 = 0.9909). The mean intra- and inter-assay CV for both serum and plasma samples was <5 %. The NeuMoDx HCV-RNA Assay demonstrates high subtype-independent comparability, linearity, and reproducibility for the quantification of HCV-RNA in serum and plasma samples from chronically infected patients.

2.
Nephrol Dial Transplant ; 39(3): 483-495, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-37858309

RESUMO

BACKGROUND: The objective of this study was to investigate the utility of neutrophil gelatinase-associated lipocalin (NGAL) and calprotectin (CPT) to predict long-term graft survival in stable kidney transplant recipients (KTR). METHODS: A total of 709 stable outpatient KTR were enrolled >2 months post-transplant. The utility of plasma and urinary NGAL (pNGAL, uNGAL) and plasma and urinary CPT at enrollment to predict death-censored graft loss was evaluated during a 58-month follow-up. RESULTS: Among biomarkers, pNGAL showed the best predictive ability for graft loss and was the only biomarker with an area under the curve (AUC) > 0.7 for graft loss within 5 years. Patients with graft loss within 5 years (n = 49) had a median pNGAL of 304 [interquartile range (IQR) 235-358] versus 182 (IQR 128-246) ng/mL with surviving grafts (P < .001). Time-dependent receiver operating characteristic analyses at 58 months indicated an AUC for pNGAL of 0.795, serum creatinine-based Chronic Kidney Disease Epidemiology Collaboration estimated glomerular filtration rate (eGFR) had an AUC of 0.866. pNGAL added to a model based on conventional risk factors for graft loss with death as competing risk (age, transplant age, presence of donor-specific antibodies, presence of proteinuria, history of delayed graft function) had a strong independent association with graft loss {subdistribution hazard ratio (sHR) for binary log-transformed pNGAL [log2(pNGAL)] 3.4, 95% confidence interval (CI) 2.24-5.15, P < .0001}. This association was substantially attenuated when eGFR was added to the model [sHR for log2(pNGAL) 1.63, 95% CI 0.92-2.88, P = .095]. Category-free net reclassification improvement of a risk model including log2(pNGAL) in addition to conventional risk factors and eGFR was 54.3% (95% CI 9.2%-99.3%) but C-statistic did not improve significantly. CONCLUSIONS: pNGAL was an independent predictor of renal allograft loss in stable KTR from one transplant center but did not show consistent added value when compared with baseline predictors including the conventional marker eGFR. Future studies in larger cohorts are warranted.


Assuntos
Transplante de Rim , Humanos , Proteínas de Fase Aguda , Aloenxertos , Biomarcadores , Lipocalina-2 , Lipocalinas , Proteínas Proto-Oncogênicas
3.
Sci Rep ; 13(1): 13206, 2023 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-37580353

RESUMO

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.


Assuntos
COVID-19 , SARS-CoV-2 , Chlorocebus aethiops , Animais , Humanos , Pandemias , Células Vero , COVID-19/diagnóstico , COVID-19/epidemiologia , Testes Imunológicos , Sensibilidade e Especificidade
4.
PLoS One ; 18(4): e0285203, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37115793

RESUMO

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.


Assuntos
COVID-19 , Mpox , Orthopoxvirus , Humanos , Monkeypox virus/genética , SARS-CoV-2/genética
5.
J Clin Virol ; 149: 105127, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35305378

RESUMO

BACKGROUND: HIV-1 RNA quantification is a key component of treatment monitoring. OBJECTIVES: To assess the performance of a redesigned HIV-1 RNA quantitative assay that uses a dual-target approach: Xpert® HIV-1 Viral Load (VL) XC. STUDY DESIGN: Fresh and frozen samples (N = 533) from HIV-1 positive patients tested with Abbott HIV-1 assays (Alinity m and RealTime [m2000]) were retested using the new Xpert XC assay. Three samples with known underquantification using the previous single-target Xpert assay were retested. RESULTS: The Xpert XC assay yielded valid results in 98.5% (N = 528/536) of cases and showed high sensitivity in 80 fresh samples that had undetectable VLs or ≤1.7 log copies/mL with Alinity m. Linear regression and Bland-Altman analyses showed high concordance with the Abbott tests for quantified samples over a wide VL range (1.6-6.9 copies/mL), including non-B subtypes (mean difference=-0.1±0.23 log copies/mL). Mutations associated with integrase resistance did not impact the results. Very good linearity and reproducibility was shown for the tested subtypes B, CRF06_cpx, and CRF02_AG. Xpert XC VLs in samples that were previously underquantified using the original single-target Xpert assay were similar to those detected by the Abbott assays (±0.11 log copies/mL). CONCLUSIONS: The Xpert XC assay showed excellent correlation with the Abbott assays for all tested HIV-1 subtypes. Sensitivity, linearity and accuracy were high in the therapeutically relevant VL range. With a time to result of only 90 min, this on-demand decentralized assay is a safe, reliable and fast option for VL monitoring in HIV-1-infected patients.


Assuntos
Infecções por HIV , HIV-1 , HIV-1/genética , Humanos , RNA Viral/genética , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Carga Viral/métodos
6.
PLoS One ; 17(1): e0262656, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35051208

RESUMO

SARS-CoV-2, the cause of COVID-19, requires reliable diagnostic methods to track the circulation of this virus. Following the development of RT-qPCR methods to meet this diagnostic need in January 2020, it became clear from interlaboratory studies that the reported Ct values obtained for the different laboratories showed high variability. Despite this the Ct values were explored as a quantitative cut off to aid clinical decisions based on viral load. Consequently, there was a need to introduce standards to support estimation of SARS-CoV-2 viral load in diagnostic specimens. In a collaborative study, INSTAND established two reference materials (RMs) containing heat-inactivated SARS-CoV-2 with SARS-CoV-2 RNA loads of ~107 copies/mL (RM 1) and ~106 copies/mL (RM 2), respectively. Quantification was performed by RT-qPCR using synthetic SARS-CoV-2 RNA standards and digital PCR. Between November 2020 and February 2021, German laboratories were invited to use the two RMs to anchor their Ct values measured in routine diagnostic specimens, with the Ct values of the two RMs. A total of 305 laboratories in Germany were supplied with RM 1 and RM 2. The laboratories were requested to report their measured Ct values together with details on the PCR method they used to INSTAND. This resultant 1,109 data sets were differentiated by test system and targeted gene region. Our findings demonstrate that an indispensable prerequisite for linking Ct values to SARS-CoV-2 viral loads is that they are treated as being unique to an individual laboratory. For this reason, clinical guidance based on viral loads should not cite Ct values. The RMs described were a suitable tool to determine the specific laboratory Ct for a given viral load. Furthermore, as Ct values can also vary between runs when using the same instrument, such RMs could be used as run controls to ensure reproducibility of the quantitative measurements.


Assuntos
Teste de Ácido Nucleico para COVID-19/métodos , COVID-19/diagnóstico , Testes Diagnósticos de Rotina/métodos , RNA Viral/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , SARS-CoV-2/genética , Carga Viral/métodos , COVID-19/epidemiologia , COVID-19/virologia , Genes Virais , Alemanha/epidemiologia , Humanos , Reprodutibilidade dos Testes
7.
J Virol Methods ; 299: 114338, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34695479

RESUMO

BACKGROUND: Detection of SARS-CoV-2 infections relies on the use of sensitive, accurate and high throughput RT-PCR assays. OBJECTIVES: We assessed the analytical performance of the Abbott RealTime SARS-CoV-2 (RT-SARS), Alinity m SARS-CoV-2 (AlinSARS) assays and compared the clinical performance of the RT-SARS, AlinSARS, and Alinity m Resp-4-Plex (Alin4Plex) assays to the Seegene Allplex assay (Allplex) and an inhouse test (Inhouse). RESULTS: We found 100 % positive percent agreement (PPA) and 100 % negative percent agreement (NPA) comparing RT-SARS and Allplex. RT-SARS, AlinSARS and Inhouse showed 100 % NPA and 100 % PPA across all assays, except for the RdRp target of Inhouse (PPA = 84 %). Similarly, Alin4Plex and Allplex showed high agreement with specimens containing either SARS-CoV-2, influenza A, influenza B, or RSV. Detection rates of 100 % for SARS-CoV-2 at 50 copies/mL, high precision, and no cross-reactivity with non-SARS-CoV-2 respiratory pathogens were observed for RT-SARS and AlinSARS. AlinSARS detected SARS-CoV-2 in spiked throat washes and in specimens infected with SARS-CoV-2 Alpha or Beta variants. CONCLUSIONS: The newly developed RT-SARS, AlinSARS, and Alin4Plex assays proved to be useful for detecting SARS-CoV-2 RNA in clinical samples.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , RNA Viral/genética , Sensibilidade e Especificidade
8.
Front Chem ; 9: 751716, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34660540

RESUMO

Complexes based on nitrogen and sulfur containing ligands involving 3d metal centers are known for the electrocatalytic reduction of CO2. However, photocatalytical activation has rarely been investigated. We herein present results on the light-driven CO2 reduction using either Ir(dFppy)3 [Ir, dFppy = 2-(4,6-difluorophenyl)pyridine] or [Cu(xant)(bcp)]+, (Cu, xant = xantphos, bcp = bathocuproine) as photosensitizer in combination with TEA (triethylamine) as sacrificial electron donor. The 3d metal catalysts have either dptacn (dipicolyl-triazacyclononane, L N3 ) or dpdatcn (dipicolyl-diazathiocyclononane, L N2S ) as ligand framework and Fe3+, Co3+ or Ni2+ as central metal ion. It turned out that the choice of ligand, metal center and solvent composition influences the selectivity for product formation, which means that the gaseous reduction products can be solely CO or H2 or a mixture of both. The ratio between these two products can be controlled by the right choice of reaction conditions. With using Cu as photosensitizer, we could introduce an intermolecular system that is based solely on 3d metal compounds being able to reduce CO2.

9.
MMW Fortschr Med ; 163(Suppl 2): 28-35, 2021 06.
Artigo em Alemão | MEDLINE | ID: mdl-34146315

RESUMO

The steady development of the antiretroviral therapy (ART) has led to a significant change in the demands on the quality of care. There are different regional challenges.It is a non-interventional, bicentric correlation study in the form of a retrospective data analysis including data of 43 HIV-positive patients in Greifswald and 1669 in Berlin. All variables were evaluated with R. Statistical significance was assumed at a p-value of ≤ 0.05.The immunological parameters showed a significantly lower CD4+ T-lymphocyte cell count in patients from Greifswald compared to those from Berlin (B: 516/µl blood; G: 266/µl blood; p < 0.001). The supply of ART was > 80% (B: 153/184 [83.15%]; G: 36/41 [87.8%]; p = 0.64) in both cohorts and led to a permanent (> than 4 quarters) drop of the viral load below the detection limit in 115/184 [62.25%] patients in Berlin and 23/41 [56.09%] patients in Greifswald (p = 0.008).This study has shown that the quality of care for HIV-infected patients in both urban and rural areas is of a high standard and carried out in accordance with the guidelines.


Assuntos
Fármacos Anti-HIV , Infecções por HIV , Fármacos Anti-HIV/uso terapêutico , Berlim , Contagem de Linfócito CD4 , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Humanos , Estudos Retrospectivos , Carga Viral
10.
J Clin Virol ; 136: 104755, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33639408

RESUMO

OBJECTIVES: Geno2pheno[coreceptor] is a widely used tool for the prediction of coreceptor usage (viral tropism) of HIV-1 samples. For HIV-1 CRF01_AE, a significant overcalling of X4-tropism is observed when using the standard settings of Geno2pheno[coreceptor]. The aim of this study was to provide the experimental backing for adaptations to the geno2pheno[coreceptor] algorithm in order to improve coreceptor usage predictions of clinical HIV-1 CRF01_AE isolates STUDY DESIGN: V3-sequences of 20 clinical HIV-1 subtype CRF01_AE samples were sequenced and analyzed by geno2pheno[coreceptor]. In parallel, coreceptor usage was determined for these samples by replicative phenotyping in human cells in the presence of specific X4- or R5-inhibitors. RESULTS: The sole introduction of the CRF01_AE V3 region into a full-length otherwise subtype B provirus failed to produce replication-competent viral progeny. A successive genome-replacement strategy revealed that also CRF01_AE derived gag and pol sequences are necessary to generate HIV genomes with sufficient replication competence. Subsequent phenotypic analysis confirmed overcalling of X4-tropism for CRF01_AE viruses using the current version and the standard cut-off at 10% false positive rate (FPR) of geno2pheno[coreceptor]. Lowering the FPR cut-off to 2.5% reduced the X4-overcalling in our sample collection, while still allowing a safe administration of Maraviroc (MCV). CONCLUSION: This study demonstrates the successful adjustment of geno2pheno[coreceptor] rules for subtype CRF01_AE. It also supports the unique strength of combining complementing methods, namely phenotyping and genotyping, for validating new bioinformatics tools prior to application in diagnostics.


Assuntos
Infecções por HIV , HIV-1 , Ásia Oriental , Genótipo , HIV-1/genética , Humanos , Tropismo Viral
11.
Exp Clin Endocrinol Diabetes ; 129(11): 798-802, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33477181

RESUMO

INTRODUCTION: HIV infection has become a chronic, well-treatable disease and the focus of caretakers has shifted to diagnosis and treatment of comorbidities. Hypogonadism in elderly men with HIV might be of particular relevance, however, little is known about its epidemiology in contrast to non-infected peers and men with other chronic medical conditions, such as type 2 diabetes. This study aimed at comparing the prevalence of testosterone deficiency and functional hypogonadism in men ≥ 50 years in these three groups. PATIENTS AND METHODS: Multi-center, cross-sectional substudy of the German-wide 50/2010 study, including men aged 50 years or older with HIV-infection, type 2 diabetes, and controls. RESULTS: Altogether, 322 men were included (mean age: 62 years (SD±7.9)). The prevalence of testosterone deficiency in men living with HIV, type 2 diabetes, and controls was 34.5, 44.9, and 35.0%, respectively; the prevalence of functional hypogonadism was 7.7, 14.3 and 3.5%, respectively. Single-factor ANOVA demonstrated significant differences between the groups for total testosterone (p<0.001), SHBG (p<0.001), as well as for free testosterone concentrations (p=0.006). Comorbidities were, however, most important single factor in multi-factor analysis. DISCUSSION: Despite a comparable prevalence of testosterone deficiency, functional hypogonadism was more frequent in men living with HIV when compared to non-infected controls. This was the result of a higher burden of symptoms that might, however, also be secondary to other conditions. Number of comorbidities was a more important factor than belonging to one of the groups.


Assuntos
Envelhecimento/sangue , Diabetes Mellitus Tipo 2/sangue , Infecções por HIV/sangue , Hipogonadismo/sangue , Globulina de Ligação a Hormônio Sexual/metabolismo , Testosterona/deficiência , Idoso , Comorbidade , Estudos Transversais , Diabetes Mellitus Tipo 2/epidemiologia , Alemanha/epidemiologia , Infecções por HIV/epidemiologia , Humanos , Hipogonadismo/epidemiologia , Masculino , Pessoa de Meia-Idade
12.
Clin Infect Dis ; 72(3): 503-509, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-32227124

RESUMO

Human immunodeficiency virus-2 (HIV-2) is endemic in some countries in West Africa. Due to the lower prevalence in industrialized countries, there is limited experience and knowledge on the management of individuals living with HIV-2 in Europe. Compared to HIV-1, there are differential characteristics of HIV-2 regarding diagnostic procedures, the clinical course, and, most importantly, antiretroviral therapy. We integrated the published literature on HIV-2 (studies and reports on epidemiology, diagnostics, the clinical course, and treatment), as well as expert experience in diagnosing and clinical care, to provide recommendations for a present standard of medical care of those living with HIV-2 in Western European countries, including an overview of strategies for diagnosis, monitoring, and treatment, with suggestions for effective drug combinations for first- and second-line treatments, post-exposure prophylaxis, and the prevention of mother-to-child transmission, as well as listings of mutations related to HIV-2 drug resistance and C-C motif chemokine receptor type 5 and C-X-C motif chemokine receptor type 4 coreceptor tropism.


Assuntos
Fármacos Anti-HIV , Infecções por HIV , África Ocidental , Fármacos Anti-HIV/uso terapêutico , Criança , Europa (Continente) , Feminino , Infecções por HIV/diagnóstico , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , HIV-2/genética , Humanos , Transmissão Vertical de Doenças Infecciosas , Padrão de Cuidado
13.
J Clin Virol ; 129: 104514, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32688328

RESUMO

BACKGROUND: Accurate molecular methods to detect and quantify hepatitis B virus (HBV) DNA are essential to diagnose chronic infections, guide treatment decisions, assess response to treatment, and determine risk of HBV-related complications. New generations of real-time HBV DNA assay platforms provide results in less than 2-3 h, with continuous loading of specimens and true random-access capability. OBJECTIVES: We examined the clinical performance of the new Alinity m HBV assay, run on the fully automated, continuous, random-access Alinity m platform, to accurately detect and quantify HBV DNA in a large series of patient samples infected with different HBV genotypes frequently encountered in clinical practice. STUDY DESIGN: This international, multisite study assessed the precision and reproducibility of the Alinity m HBV assay and compared its performance to four HBV assays currently in clinical use. RESULTS: The Alinity m HBV assay demonstrated linear quantitation of HBV DNA in plasma samples, with high precision (coefficient of variation 4.1 %-8.8 %) and reproducibility. The Alinity m HBV assay showed excellent correlation (correlation coefficients ≥0.947) with comparator HBV assays, with an overall observed bias ranging from -0.07 to 0.17 Log10 IU/mL. 97 % of quantifiable patient results were <1 Log10 IU/mL different than the respective comparator assays, with comparable results across HBV genotypes. CONCLUSIONS: The newly developed real-time PCR-based Alinity m HBV assay is sensitive, reproducible, and accurately quantifies HBV DNA levels from HBsAg-positive patients across the full dynamic range of quantification.


Assuntos
Vírus da Hepatite B , Hepatite B , DNA Viral , Vírus da Hepatite B/genética , Humanos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Carga Viral
14.
J Clin Virol ; 129: 104531, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32688330

RESUMO

BACKGROUND: Nucleic acid testing is essential for the detection and quantification of HCV RNA in the diagnosis of HCV infection and treatment monitoring. The Alinity m HCV assay was recently developed by Abbott Molecular for rapid detection and quantification of HCV RNA on the fully automated, continuous, random-access Alinity m analyzer. OBJECTIVES: Our study assessed the performance of the new Alinity m HCV assay for detection and quantification of HCV RNA in a large series of patient samples of various genotypes. This international, multicentric study evaluated the linearity, precision, and reproducibility of the Alinity m HCV assay and its performance in comparison to three other HCV assays currently used in clinical practice. RESULTS: The Alinity m HCV assay demonstrated high linearity (correlation coefficient r = 1.00), precision (coefficients of variation [CV] 6.6-13.5 %) and reproducibility (CV 1.7-4.3 % across three control lots). At a concentration near the lower limit of detection, the Alinity m HCV assay exhibited >98 % detectability. The Alinity m HCV assay showed excellent correlation with comparator HCV assays in serum (n = 406) and plasma (n = 1401) samples (correlation coefficients ≥0.96, bias 0.01 to 0.14 Log10 IU/mL). More than 95 % of the quantified results with the Alinity m HCV assay were less than mean bias ± 1.96 SD different from those of the comparator assays. CONCLUSIONS: The newly developed Alinity m HCV assay is sensitive, reproducible, and accurately quantifies HCV RNA levels in serum and plasma samples from patients with chronic HCV infection, with no impact of HCV genotype on assay performance.


Assuntos
Hepacivirus , Hepatite C , Genótipo , Hepacivirus/genética , Humanos , RNA Viral , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Carga Viral
15.
J Clin Virol ; 129: 104530, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32688329

RESUMO

BACKGROUND: Accurate, rapid detection of HIV-1 RNA is critical for early diagnosis, treatment decision making, and long-term management of HIV-1 infection. OBJECTIVE: We evaluated the diagnostic performance of the Alinity m HIV-1 assay, which uses a dual target/dual probe design against highly conserved target regions of the HIV-1 genome and is run on the fully automated Alinity m platform. STUDY DESIGN: This was an international, multisite study that compared the diagnostic performance of the Alinity m HIV-1 assay to four commercially available HIV-1 assays routinely used in nine independent clinical laboratories. Alinity m HIV-1 assay precision, detectability, and reproducibility was compared across four study sites. RESULTS: The Alinity m HIV-1 assay produced comparable results to currently available HIV-1 assays (correlation coefficient >0.995), with an overall bias of -0.1 to 0.10 Log10 copies/mL. The Alinity m HIV-1 assay and its predecessor m2000 HIV-1 assay demonstrated comparable detection of 16 different HIV-1 subtypes (R2 = 0.956). A high level of agreement (>88 %) between all HIV-1 assays was seen near clinical decision points of 1.7 Log10 copies/mL (50 copies/mL) and 2.0 Log10 copies/mL (200 copies/mL). Alinity m HIV-1 assay precision was 0.08 and 0.21 Log10 copies/mL at VLs of 1000 and 50 copies/mL, respectively, with a high level of detectability (≥97 % hit rate) and reproducibility across sites. CONCLUSIONS: The Alinity m HIV-1 assay provides comparable diagnostic accuracy to current HIV-1 assays, and when run on the Alinity m system, has the capacity to shorten the time between diagnosis and treatment.


Assuntos
Infecções por HIV , HIV-1 , HIV-1/genética , Humanos , RNA Viral , Kit de Reagentes para Diagnóstico , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Carga Viral
16.
J Virol Methods ; 279: 113839, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32087189

RESUMO

Hepatitis C virus (HCV) antigen/antibody (Ag/Ab) assays offer the benefit of reducing the window period compared to assays that detect only HCV-Ab. In this study the performance of the Murex Ag/Ab (Murex, Abbott) and Monolisa Ag/Ab Ultra (Monolisa, Bio-Rad) ELISAs was compared for the use of filter dried serum/plasma spots (DS/PS) with a focus on the sensitivity and the percentage of correct positive test results. Correct positive ELISA results were assumed for samples that subsequently tested positive for HCV RNA by RT-qPCR, or RNA negative samples that tested positive in a Western blot (confirmed ELISA results). Sensitivity was evaluated from DS/PS eluates using HCV seroconversion panels [plasma samples of subtypes-(St) 1a, 2b)] and longitudinal HCV antibody positive serum panels (St 1b, 2b, 3a, and 4d). The proportion of correct positive test results was evaluated using 1102 newly diagnosed HIV positive clinical dried serum spots (DSS) eluates for screening of potential HCV co-infection. For the plasma HCV seroconversion samples, which were used as a reference for DSS eluates, the Murex became reactive earlier for antigen positive bleeds. However, for the HCV antibody positive eluates and dilutions thereof, the Monolisa demonstrated a superior sensitivity. Of the clinical DSS 22.8 % (28/123) of samples reactive in the Murex were negative in a subsequent RT-qPCR and Western blot, while only 1.9 % (2/105) of the samples reactive in the Monolisa were negative in these confirmatory assays. Our results indicate that the Monolisa provides fewer false positive results for HCV detection in DSS, whereas for undiluted plasma or serum samples, the Murex can serve as an additional diagnostic tool to narrow the window period.


Assuntos
Infecções por HIV/diagnóstico , Anticorpos Anti-Hepatite C/sangue , Antígenos da Hepatite C/sangue , Hepatite C/diagnóstico , Imunoensaio/métodos , Adulto , Hepacivirus , Hepatite C/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Plasma , Kit de Reagentes para Diagnóstico , Sensibilidade e Especificidade
17.
J Immunol Methods ; 479: 112744, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31958450

RESUMO

Monitoring recency of infection helps to identify current transmission in vulnerable populations for effective disease control. We have established an in-house avidity based hepatitis C virus (HCV) recency assay based on the Monolisa Anti-HCV PLUS Version 3 ELISA kit for use of dried serum/plasma spots (DS/PS) in order to distinguish recent and long-term infections. A first panel of DS/PS (n = 218; genotype 1 n = 170 and non-genotype 1 n = 48) consisting of primary and at least one follow up sample was used to analyze the temporal changes of the Avidity Index (AI) over time. Sub-panels of longitudinal DS/PS (n = 66) and acute cases (<26 weeks; n = 34) were taken to calculate the Mean Duration of Recent Infection (MDRI) and the False Long-term Rate (FLTR), respectively. A second panel of DS/PS >104 weeks (n = 132) and a third panel of DS/PS prepared from resolved infections (≥180 days since last positive; n = 32) were used to calculate the False Recent Rate (FRR). For all genotypes, the optimal AI cut-off was determined to be 40% resulting in an MDRI of 364 days (95% CI: 223-485). FLTR was 5.9% (95% CI: 0.7-19.7), 8.3% (95% CI: 1-27), and 0% (-) and FRR was 13.6% (95% CI: 8.3-20.7), 11.7% (95% CI: 6.6-19), and 30.6% (95% CI: 9.1-61.4) for all genotypes, genotype 1, and non-genotype 1 infections, respectively. For resolved infections, the FRR was 53.1% (95% CI: 35.8-70.4). Thus, this assay performs particularly well for genotype 1 reaching a high rate of correct discriminations between infections acquired less than a year before diagnosis and those acquired earlier by applying an AI cut-off of 40%. Due to a rapid decline in avidity post resolution of an HCV infection this assay is not recommended to be used in HCV RNA negative patients.


Assuntos
Teste em Amostras de Sangue Seco/métodos , Ensaio de Imunoadsorção Enzimática/métodos , Genótipo , Hepacivirus/fisiologia , Anticorpos Anti-Hepatite C/metabolismo , Hepatite C/imunologia , Imunoglobulina G/metabolismo , Afinidade de Anticorpos , Estudos de Coortes , Feminino , Seguimentos , Alemanha , Humanos , Masculino , Pessoa de Meia-Idade , Padrões de Referência , Sensibilidade e Especificidade
18.
Front Med (Lausanne) ; 7: 616648, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33614675

RESUMO

Objective: COVID-19 is a highly contagious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Preventing in-hospital infections is crucial to protect patients and hospital staff. Methods: At the very beginning of the COVID-19 pandemic, the German Heart Center initiated obligatory wearing of surgical face masks for patients and employees, SARS-CoV-2 screening for all patients, and symptom-based testing for employees. In addition, access restriction, closure of outpatient departments, and postponing non-urgent procedures were implemented with community-initiated regulations. Results: During the observation period (03/16/2020-04/27/2020), 1,128 SARS-CoV-2 tests were performed in 983 persons (1.1 tests/person; 589 in patients and 394 in hospital employees). Up to 60% of the clinical workforce was tested based on symptoms and risk (62.5% symptoms, 19.3% direct or indirect contact to known COVID-19, 4.5% returnee from risk area, 13.7% without specific reason). Patient testing for SARS-CoV-2 was obligatory (100% tested). The overall prevalence of positive tests during the observation period was 0.4% (n = 5 out of 1,128 tests performed). The incidence of new infections with SARS-CoV-2 was 0.5% (n = 5 out of 983 individuals; three healthcare workers, two patients). No nosocominal infections occurred, despite a mean number of 14.8 in-hospital contacts. Conclusion: Comprehensive SARS-CoV-2 testing and surgical face masks for patients and hospital staff, in addition to others measures, are key factors for the early detection of COVID-19 and to prevent spreading in the vulnerable hospital population.

20.
J Org Chem ; 84(6): 3491-3499, 2019 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-30788966

RESUMO

The reactivity of phosphanyl phosphonates toward diacetylenic ketones was studied. Reactions resulted in the selective formation of phospholones via phosphaalkene intermediates. Phospholones were obtained in yields of 37-96% depending on the substituent on the acetylenic unit. Reduction of the phenyl-substituted phospholone resulted in the formation of a persubstituted phosphole bearing a hydroxyl group in position 3 in 64% yield, and its oxidation led to oxaphospholone in 77% yield. Both of these modifications led to substantial changes in the optoelectronic properties of the compounds and bathochromic shifts of the longest wavelength absorption maximum.

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