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1.
MethodsX ; 13: 102878, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-39188587

RESUMO

Screening strategies for GMO detection in food and feed are a crucial aspect in GMO testing laboratories for streamlining the analytical workflow and reducing turnaround time and costs. These strategies can be more or less complex or even be targeted according to the ingredients in the product, but whatever the choice, a good basic approach is generally based on the search for 35S promoter (P35S), nos-terminator (T-nos) and FMV promoter (P-FMV). In this study, we compare the singleplex real time PCR method for P35S, T-nos and P-FMV detection currently adopted by the Italian National Reference Laboratory for GM food and feed (NRL) with three commercial kits available on the market for giving a greater choice to consider the best approach suitable to the official control laboratories that are different from each other.•The NRL optimized singleplex PCR methods and the three commercial kits fully respect all the validation parameters criteria according to the minimum performance requirements (MPR) of ENGL [1]•Screening strategies for GMO detection in food and feed are a crucial aspect in GMO testing laboratories and being the commercial kits different from each other, the laboratory can choose the methods best suit their needs reducing turnaround time and costs.

2.
Mol Cell Biochem ; 479(3): 679-691, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37166542

RESUMO

Extracellular vesicles (EVs) secreted by various cells offer great potential for use in the diagnosis and treatment of disease. EVs are heterogeneous membranous vesicles. Exosomes are a subtype of EVs, 40-150 nm spherical vesicles with a lipid layer derived from endosomes. Exosomes, which are involved in signal transduction and maintain homeostasis, are released from almost all cells, tissues, and body fluids. Although several methods exist to isolate and characterize EVs and exosomes, each technique has significant drawbacks and limitations that prevent progress in the field. New approaches in the biology of EVs show great potential for isolating and characterizing EVs, which will help us better understand their biological function. The strengths and limitations of conventional strategies and novel methods (microfluidic) for EV isolation are outlined in this review. We also present various exosome isolation techniques and kits that are commercially available and assess the global market demand for exosome assays.


Assuntos
Exossomos , Vesículas Extracelulares , Transdução de Sinais , Endossomos
3.
J Clin Microbiol ; 60(12): e0113522, 2022 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-36321820

RESUMO

The high prevalence of macrolide resistance in Mycoplasma genitalium results in an increased reliance on moxifloxacin, the second-line treatment; however, moxifloxacin resistance has also emerged. Because assays that can detect fluoroquinolone resistance-associated mutations will be useful for the management of macrolide-resistant M. genitalium infections, we evaluated the performance of three commercial assays (the Allplex MG & MoxiR Assay [Seegene], LightMix Modular parC kit [TIBMOLBIOL], and MGMO qPCR [NYtor) in comparison with parC gene Sanger sequencing used as the reference. Between January 2018 and December 2020, remnants of M. genitalium-positive clinical specimens received at the French National Reference Center for Bacterial Sexually Transmitted Infections were collected if a Sanger sequencing result was obtained for the parC gene. Overall, 368 M. genitalium-positive specimens were assessed. The clinical sensitivities for the detection of the ParC mutations that are likely of clinical significance were 91.8% (95% CI = 83.2 to 96.2), 98.6% (95% CI = 92.4 to 99.8), and 94.4% (95% CI = 86.6 to 97.8) for the Allplex MG & MoxiR, LightMix Modular parC, and MGMO qPCR kits, respectively, with no significant difference between the three kits. The clinical specificity of the Allplex MG & MoxiR and MGMO qPCR kits was 100% (95% CI = 97.7 to 100 and 98.7 to 100, respectively), which was significantly higher than the specificity of the LightMix Modular parC kit of 95.4% (95%CI = 92.3 to 97.3), for which the interpretation of melting curves may be misleading. These kits should be useful for the selection of antimicrobials in macrolide-resistant M. genitalium infections, although further developments may be necessary because parC mutations involved in fluoroquinolone resistance have not been precisely determined.


Assuntos
Infecções por Mycoplasma , Mycoplasma genitalium , Humanos , Fluoroquinolonas/farmacologia , Fluoroquinolonas/uso terapêutico , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Moxifloxacina/uso terapêutico , Mycoplasma genitalium/genética , Patologia Molecular , Macrolídeos/farmacologia , Farmacorresistência Bacteriana/genética , Infecções por Mycoplasma/diagnóstico , Infecções por Mycoplasma/epidemiologia , RNA Ribossômico 23S/genética , DNA Bacteriano/genética , Mutação
4.
J Vector Borne Dis ; 59(1): 98-101, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35708411

RESUMO

Dengue, a vector-borne disease remains as one of the most serious public health problems globally. Incidence of this disease is on an increasing trend and currently over a billion people in tropical and subtropical regions are at risk. In the absence of an operational vaccine, prevention of dengue virus (DENV) is primarily focused upon controlling mosquito vectors. Mosquito vector surveillance programmes require simple and rapid tools to detect mosquitoes infected with DENV. Here, we tested the commercially available DENV Detect™ NS1 ELISA kit (InBios International, Inc.) for detection of recombinant DENV-NS1 protein in Aedes mosquito samples. The kit was evaluated to find out the minimum detection limit of recombinant DENV-2 NS1 protein following the manufacturer's instructions. Initially, the NS1 protein detection threshold of the kit was determined and later the assay was standardized for detection of NS1 protein in Aedes aegypti mosquito pools containing 5, 10 and 25 mosquitoes. The ELISA kit displayed high sensitivity towards detection of recombinant dengue virus-2 NS1 protein in mosquito pools (up to 25 mosquitoes per pool) at 25 pico gram concentration. Since the commercial NS1 ELISA is highly sensitive and follows a very simple procedure, it could be employed for DENV surveillance in Aedes aegypti mosquitoes, after carrying out laboratory and field bioassays with DENV infected specimens.


Assuntos
Aedes , Vírus da Dengue , Dengue , Animais , Vírus da Dengue/genética , Ensaio de Imunoadsorção Enzimática/métodos , Humanos , Mosquitos Vetores , Proteínas Recombinantes/genética
5.
Rev Esp Quimioter ; 35(4): 401-405, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35723605

RESUMO

OBJECTIVE: Since the first cases of SARS-CoV-2 appeared, there have been numerous techniques that have been developed for the diagnosis or monitoring of infection, both direct and serological techniques. Choosing a good diagnostic tool is essential for epidemiological control. The objective was to compare five commercialized RT-PCR techniques in real time, in sensitivity, specificity and agreement for the detection of SARS-CoV-2. METHODS: Five commercial RT-PCR kits for the detection of SARS-CoV-2 were compared. Eight known positive samples were taken and subjected to seven different dilutions or concentrations, and another 135 negative samples were used to determine sensitivity, specificity, and agreement values. RESULTS: The sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) for the Palex, Roche and GeneXpert techniques with respect to Seegene were identical, corresponding to 98.21%, 100%, 100% and 99.26% respectively. For Becton Dickinson the sensitivity was 89.28%, the specificity of 100%, the PPV of 100% and the NPV of 95.74%. The agreement using the Kappa index for Palex, Roche and GeneXpert was 0.9892, while the agreement for Becton Dickinson was with a Kappa index of 0.9215. CONCLUSIONS: All commercial RT-PCR kits had high sensitivities and specificities, as well as PPV, NPV, and concordance.


Assuntos
COVID-19 , SARS-CoV-2 , COVID-19/diagnóstico , Teste para COVID-19 , Humanos , Reação em Cadeia da Polimerase , SARS-CoV-2/genética , Sensibilidade e Especificidade
6.
Clin Microbiol Infect ; 28(5): 733.e7-733.e13, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-34610459

RESUMO

OBJECTIVES: We evaluated the clinical performances of four multiplex real-time PCR commercial kits for the detection of Chlamydia trachomatis, Neisseria gonorrhoeae, Mycoplasma genitalium and Trichomonas vaginalis: the STI PLUS ELITe MGB kit (ELITechGroup), N. gonorrhoeae/C. trachomatis/M. genitalium/T.vaginalis Real-TM kit (Sacace Biotechnologies), Allplex STI Essential kit (Seegene), and FTD Urethritis Plus kit (Fast-Track Diagnostics). METHODS: The kit performance for C. trachomatis, N. gonorrhoeae, M. genitalium and T. vaginalis detection was compared to that of the cobas CT/NG and TV/MG kits (Roche Diagnostics) using 425 samples, mainly urine and cervicovaginal, throat and rectal swabs. Detection of Ureaplasma parvum, U. urealyticum and Mycoplasma hominis were compared to that of in-house TaqMan PCRs. RESULTS: The four kits showed good performances for the detection of C. trachomatis. They all presented a low positive agreement for the detection of M. genitalium and T. vaginalis (ranges 63.3-74.1% and 51.2-68.4%, respectively) compared to the cobas MG/TV kit. The Seegene and Sacace kits showed additional low positive agreement for the detection of N. gonorrhoeae (71.2%, 95%CI 61.8-79.0 and 63.1%, 95%CI 53.5-71.8, respectively). We observed a slight but significant lower negative agreement for N. gonorrhoeae detection using the ELITechGroup kit (92.5%, 89.1-94.9) and for M. genitalium detection using the Fast-Track kit (93.2%, 89.6-95.7) compared to other kits. CONCLUSION: Multiplex real-time PCR kits are convenient methods for the detection of several pathogens associated with sexually transmitted infections (STIs) in a single step, but colonizing Ureaplasma spp. and M. hominis species should not be included in these kits. Users should be aware of the weak performance of some kits for the detection of M. genitalium and T. vaginalis.


Assuntos
Gonorreia , Infecções por Mycoplasma , Mycoplasma genitalium , Infecções Sexualmente Transmissíveis , Trichomonas vaginalis , Uretrite , Chlamydia trachomatis/genética , Feminino , Humanos , Masculino , Infecções por Mycoplasma/diagnóstico , Mycoplasma genitalium/genética , Neisseria gonorrhoeae/genética , Reação em Cadeia da Polimerase em Tempo Real/métodos , Infecções Sexualmente Transmissíveis/diagnóstico , Infecções Sexualmente Transmissíveis/microbiologia , Trichomonas vaginalis/genética , Ureaplasma
7.
Artigo em Inglês | MEDLINE | ID: mdl-34887225

RESUMO

INTRODUCTION: The sensitivity and specificity of diagnostic techniques for Chagas disease depend largely on the antigens and targets used and on the immune response and characteristics of the infection of the population where it is applied, hence the need for evaluation of the diagnostic techniques available in a given area. So, the objective of this work was to evaluate two commercial kits for the immunological and molecular diagnosis of Chagas disease in endemic areas of Venezuela. METHODS: The evaluated kits were: Chagas ELISA IgG+IgM® and Speed Oligo Chagas® (Vircell®, Granada, Spain). They were evaluated with 129 samples (35 from patients in the acute phase, 33 in the chronic phase, 31 from patients with other diseases, and 30 from healthy individuals). The results were compared with those obtained in the conventional ELISA and PCR-satellite DNA tests for Trypanosoma cruzi. RESULTS: With Chagas ELISA IgG+IgM® a sensitivity of 94.1% and specificity of 93.4% were obtained, with Speed Oligo Chagas® a sensitivity of 92.6% and specificity of 100% were achieved, values similar to those showed by conventional ELISA and satDNA-PCR. CONCLUSION: The sensitivity and specificity of the commercial kits evaluated make them suitable for the diagnosis of Chagas disease in endemic areas of Venezuela.


Assuntos
Doença de Chagas , Trypanosoma cruzi , Doença de Chagas/diagnóstico , Doença de Chagas/epidemiologia , Ensaio de Imunoadsorção Enzimática/métodos , Humanos , Sensibilidade e Especificidade , Venezuela/epidemiologia
8.
Biotechnol Adv ; 54: 107814, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34389465

RESUMO

Exosomes are a subset of extracellular vesicles released from various cells, and they can be found in different bodily fluids. Exosomes have been utilized as biomarkers to diagnose many diseases and to monitor therapy efficiency as they represent the status and origin of the cell, which they are released from. Considering that they co-exist in bodily fluids with other types of particles, their isolation still remains challenging since conventional methods are time-consuming, user-dependent, and result in low isolation yield. This review summarizes the conventional strategies and microfluidic-based methods for exosome isolation along with their strengths and limitations. In particular, microfluidic devices emerge as a promising approach to tackle the existing limitations of conventional methods, and they provide unique features, such as operating with minute volume of samples and rapid process, in order to isolate exosomes with the high yield and the high purity, which make them unprecedented tools for molecular biology and clinical applications in exosome research. This review further elaborates on the existing microfluidic-based exosome isolation methods and denotes their benefits and drawbacks. Herein, we also introduce various commercially available platforms and kits for exosome isolation along with their working principles.


Assuntos
Exossomos , Vesículas Extracelulares , Biomarcadores , Exossomos/metabolismo , Vesículas Extracelulares/metabolismo , Dispositivos Lab-On-A-Chip , Microfluídica
9.
J Med Virol ; 93(9): 5618-5622, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33913558

RESUMO

The ongoing severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has led to the design and development of multiple reverse-transcription polymerase chain reaction kits aimed to facilitate the rapid scale-up of molecular testing for massive screening. We evaluated the diagnostic performance of nine commercial kits, which showed optimal performance and high discriminatory power. However, we observed differences in terms of sensitivity, specificity, and E gene Ct Values and discuss these results in light of the influence of SARS-CoV-2 genetic variability and its potential impact in current molecular diagnostic assays.


Assuntos
COVID-19/diagnóstico , Kit de Reagentes para Diagnóstico/normas , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , SARS-CoV-2/genética , SARS-CoV-2/isolamento & purificação , COVID-19/virologia , Teste para COVID-19 , Colômbia , Humanos , Técnicas de Diagnóstico Molecular , Sensibilidade e Especificidade
10.
BMC Infect Dis ; 21(1): 336, 2021 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-33838648

RESUMO

BACKGROUND: Tuberculosis (TB) is a serious infectious disease caused by Mycobacterium tuberculosis (MTB). An estimated 1.7 billion people worldwide are infected with Mycobacterium tuberculosis (LTBI) during the incubation period without any obvious symptoms. Because of MTB's high infection and mortality rates, there is an urgent need to develop a fast, portable, and sensitive diagnostic technology for its detection. METHODS: We included research from PubMed, Cochrane Library, Web of Science, and Embase and extracted the data. MetaDisc and STATA were used to build forest plots, Deek's funnel plot, Fagan plot, and bivariate boxplot for analysis. RESULTS: Forty-six articles were analyzed, the results of which are as follows: sensitivity and specificity were 0.92 (0.91-0.93) and 0.95 (0.94-0.95) respectively. The NLR and PLR were 0.04 (95% CI 0.03-0.07) and 25.32 (95% CI 12.38-51.78) respectively. DOR was 639.60 (243.04-1683.18). The area under the SROC curve (AUC) was 0.99. CONCLUSIONS: MPT64 exhibits good diagnostic efficiency for MTB. There is no obvious heterogeneity between the three commercial kits.


Assuntos
Antígenos de Bactérias/imunologia , Mycobacterium tuberculosis , Kit de Reagentes para Diagnóstico , Tuberculose/microbiologia , Ensaio de Imunoadsorção Enzimática/métodos , Humanos , Imunoensaio/métodos , Mycobacterium tuberculosis/isolamento & purificação , Sensibilidade e Especificidade , Tuberculose/diagnóstico
11.
J Clin Microbiol ; 59(6)2021 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-33731412

RESUMO

The increasing frequency of macrolide resistance is an emerging issue in the treatment of Mycoplasma genitalium infection. Because evaluation of new commercial kits detecting M. genitalium and macrolide resistance is needed, we evaluated the performance and handling characteristics of the Allplex MG & AziR (Seegene), the Macrolide-R/MG ELITe MGB (ELITechGroup), and the ResistancePlus MG FleXible (SpeeDx-Cepheid) kits in comparison with those of an in-house real-time PCR and 23S rRNA gene sequencing used as the reference. A total of 239 urogenital specimens (135 M. genitalium-positive and 104 M. genitalium-negative specimens) collected between April and December 2019 at the French National Reference Center for Bacterial Sexually Transmitted Infections were assessed. The overall agreement for M. genitalium detection of the three commercial kits compared with the in-house real-time PCR was 94.6 to 97.6%, and there was no significant difference. A total of 97 specimens were found to be M. genitalium positive with the three kits and were used to assess macrolide resistance detection. The clinical sensitivities for resistance detection were 74.5% (95% confidence interval, 61.7 to 84.2%), 96.2% (87.2 to 99.0%), and 92.8% (82.7 to 97.1%) for the Allplex MG & AziR, Macrolide-R/MG ELITe MGB, and ResistancePlus MG FleXible kits, respectively. The sensitivity of the Macrolide-R/MG ELITe MGB kit was significantly higher than that of the Allplex MG & AziR kit. The clinical specificity for resistance detection of the three kits was 97.4 to 97.6%. The random-access possibility, input sample volume, and DNA extract availability for detecting resistance to other antibiotics may also influence the selection of a commercial kit by diagnostic laboratories.


Assuntos
Infecções por Mycoplasma , Mycoplasma genitalium , Antibacterianos/farmacologia , Farmacorresistência Bacteriana , Humanos , Macrolídeos/farmacologia , Infecções por Mycoplasma/diagnóstico , Mycoplasma genitalium/genética , Patologia Molecular
12.
J Fungi (Basel) ; 7(2)2021 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-33671676

RESUMO

Candida auris is an emerging pathogen with resistance to many commonly used antifungal agents. Infections with C. auris require rapid and reliable detection methods to initiate successful medical treatment and contain hospital outbreaks. Conventional identification methods are prone to errors and can lead to misidentifications. PCR-based assays, in turn, can provide reliable results with low turnaround times. However, only limited data are available on the performance of commercially available assays for C. auris detection. In the present study, the two commercially available PCR assays AurisID (OLM, Newcastle Upon Tyne, UK) and Fungiplex Candida Auris RUO Real-Time PCR (Bruker, Bremen, Germany) were challenged with 29 C. auris isolates from all five clades and eight other Candida species as controls. AurisID reliably detected C. auris with a limit of detection (LoD) of 1 genome copies/reaction. However, false positive results were obtained with high DNA amounts of the closely related species C. haemulonii, C. duobushaemulonii and C. pseudohaemulonii. The Fungiplex Candida Auris RUO Real-Time PCR kit detected C. auris with an LoD of 9 copies/reaction. No false positive results were obtained with this assay. In addition, C. auris could also be detected in human blood samples spiked with pure fungal cultures by both kits. In summary, both kits could detect C. auris-DNA at low DNA concentrations but differed slightly in their limits of detection and specificity.

13.
Clin Microbiol Infect ; 27(6): 909.e1-909.e5, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32771642

RESUMO

OBJECTIVES: Lymphogranuloma venereum (LGV) is a sexually transmitted infection (STI) caused by Chlamydia trachomatis (CT) genovars L. The identification of LGV is of therapeutic interest because treatment requires 3 weeks of doxycycline compared with 1 week for infection with a non-L strain. The aim of this study was to evaluate the performance of four commercial real-time PCR kits in comparison with the reference methods used for LGV diagnosis by the French National Reference Centre (NRC) for bacterial STIs. METHODS: A total of 215 French CT-positive anorectal specimens collected consecutively in 2017 were used (66 LGV and 149 non-LGV). Among these, 92 were collected from symptomatic men who have sex with men (MSM) and 123 from asymptomatic MSM using pre-exposure prophylaxis. Four commercial assays were evaluated; a single-plex assay RealCycler CHSL kit (Progenie Molecular), tested on all the specimens, and three multiplex kits, the RealCycler Universal ULCGEN (Progenie Molecular), the Allplex Genital Ulcer Assay (Seegene) and the VIASURE Haemophilus ducreyi + CT LGV Real Time PCR Detection kit (CerTest Biotec), tested on the 92 samples from symptomatic MSM. Clinical performance was determined in comparison to the in-house real time PCR targeting the pmpH and the ompA gene sequencing. RESULTS: Overall agreement ranged between 91.3% and 100% (95% CI 83.7-100%) with very good Kappa index values (>0.8). The clinical sensitivities and specificities varied between 91% and 100% (95% CI 80.8-100%), and 97% and 100% (95% CI 87.1-100%), respectively, with some kits performing better than others. DISCUSSION: The four assays showed very good performance for the detection of LGV on anorectal specimens.


Assuntos
Infecções por Chlamydia/diagnóstico , Chlamydia trachomatis/isolamento & purificação , Linfogranuloma Venéreo/diagnóstico , Reação em Cadeia da Polimerase em Tempo Real/métodos , Doenças Retais/diagnóstico , Infecções por Chlamydia/complicações , Infecções por Chlamydia/microbiologia , Humanos , Linfogranuloma Venéreo/complicações , Masculino , Minorias Sexuais e de Gênero
14.
J Med Virol ; 93(4): 2281-2286, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33230819

RESUMO

There are more than 350 real-time polymerase chain reaction (RT-PCR) coronavirus disease-2019 (COVID-19) testing kits commercially available but these kits have not been evaluated for pooled sample testing. Thus, this study was planned to compare and evaluate seven commercially available kits for pooled samples testing. Diagnostic accuracy of (1) TRUPCR SARS-CoV-2 Kit (Black Bio), (2) TaqPath RT-PCR COVID-19 Kit (Thermo Fisher Scientific), (3) Allplex 2019-nCOV Assay (Seegene), (4) Patho detect COVID-19 PCR kit (My Lab), (5) LabGun COVID-19 RT-PCR Kit (Lab Genomics, Korea), (6) Fosun COVID-19 RT-PCR detection kit (Fosun Ltd.), (7) Real-time Fluorescent RT-PCR kit for SARS CoV-2 (BGI) was evaluated on precharacterised 40 positive and 10 negative COVID-19 sample pools. All seven kits detected all sample pools with low Ct values (<30); while testing weak positive pooled samples with high Ct value (>30); the TRUPCR Kit, TaqPath Kit, Allplex Assay, and BGI RT-PCR kit showed 100% sensitivity, specificity, and accuracy. However, the Fosun kit, LabGun Kit, and Patho detect kit could detect only 90%, 85%, and 75% of weakly positive samples, respectively. We conclude that all seven commercially available RT-PCR kits included in this study can be used for routine molecular diagnosis of COVID-19. However, regarding performing pooled sample testing, it might be advisable to use those kits that performed best regarding positive identification in samples' pool, that is TRUPCR SARS-CoV-2 Kit, TaqPath RT-PCR COVID-19 Kit, Allplex 2019-nCOV Assay, and BGI Real-time RT-PCR kit for detecting SARS CoV-2.


Assuntos
Teste para COVID-19/métodos , COVID-19/diagnóstico , Kit de Reagentes para Diagnóstico , Reação em Cadeia da Polimerase em Tempo Real/métodos , SARS-CoV-2/isolamento & purificação , COVID-19/epidemiologia , Técnicas de Laboratório Clínico , Humanos , Índia/epidemiologia , Estudos Prospectivos , RNA Viral/análise , RNA Viral/genética , República da Coreia , SARS-CoV-2/genética , Sensibilidade e Especificidade , Organização Mundial da Saúde
16.
Cancer Biomark ; 29(3): 373-385, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32716349

RESUMO

BACKGROUND: Extracellular vesicles(EVs) is an emerging approach of cancer liquid biopsy. Although the precipitation-based method with commercial kits has gained popularity as the second most commonly used technique, these protocols vary tremendously with many included reagents still unknown to the community. METHODS: In this study, we assigned each of the 3 clinical plasma samples into 6 aliquots to assess five commercial EV isolation kits, in comparison with ultracentrifugation(UC). We implemented a standardized EV preparation and transcriptome analysis workflow except the EV isolation methods used. The metrics of EVs and its RNA cargo (evRNA) were compared to assess the technical variations versus the biological variations in the clinical setting. RESULTS: Although the size range of the isolated EVs demonstrated a similar distribution, we found significant technical variability among these methods, in terms of EV amount, purity, subpopulations and RNA integrity. Such variabilities were further relayed to a drastic divergence of evRNA expression on a transcriptome-wide fashion. CONCLUSIONS: Our study demonstrated a highly variable result from polymeric precipitation-based EV isolation methods, making EVs based biomarker analysis difficult to interpret and reproduce. We highlighted the importance of benchmarking and transparent reporting of the precipitation-based protocols in the liquid biopsy research.


Assuntos
Biomarcadores Tumorais/sangue , Neoplasias Ósseas/diagnóstico , Ácidos Nucleicos Livres/sangue , Exossomos/metabolismo , Osteossarcoma/diagnóstico , Adolescente , Adulto , Biomarcadores Tumorais/metabolismo , Neoplasias Ósseas/sangue , Neoplasias Ósseas/patologia , Ácidos Nucleicos Livres/metabolismo , Criança , Exossomos/ultraestrutura , Feminino , Perfilação da Expressão Gênica , Humanos , Biópsia Líquida/métodos , Estudos Longitudinais , Masculino , Microscopia Eletrônica de Transmissão , Pessoa de Meia-Idade , Osteossarcoma/sangue , Osteossarcoma/patologia , Projetos Piloto , Estudos Prospectivos , Adulto Jovem
17.
Nutr Res ; 76: 1-8, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32109763

RESUMO

This review describes the premises for accurate measurement of the gut hormone and satiety factor cholecystokinin (CCK) in circulation. Such a description is useful for nutrition and obesity research in which CCK in its satiety role has evoked considerable interest during the last decades. The background for the review is two sorts of considerations or concerns. First, CCK is a complex peptide system that in several ways challenges plasma measurements because the concentrations in plasma are very low (in the femtomolar to low picomolar range), and the bioactive CCK circulates in different molecular forms (CCK-58, -33, -22, and -8). Furthermore, there are major specificity problems because the structurally similar gastrin hormone circulates in 10- to 20-fold higher concentrations, and in addition, plasma proteins may, due to their high concentration, interfere in an unspecific way with immunoassay measurements. The second concern is that several obesity studies in recent decades have been based on commercial CCK kits with often inadequate documentation of the reliability in plasma measurement. Consequently, many plasma CCK results in today's obesity studies are difficult to compare. Moreover, the use of even fairly reliable commercial CCK kits has recently suffered from sudden discontinuation of the kit production, which has endangered several projects in nutrition and obesity research.


Assuntos
Regulação do Apetite , Pesquisa Biomédica/métodos , Análise Química do Sangue/normas , Colecistocinina/sangue , Obesidade/sangue , Resposta de Saciedade/fisiologia , Animais , Viés , Pesquisa Biomédica/normas , Proteínas Sanguíneas/metabolismo , Gastrinas/sangue , Humanos , Ciências da Nutrição , Estado Nutricional , Fragmentos de Peptídeos/sangue , Plasma/metabolismo
18.
J Clin Microbiol ; 58(2)2020 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-31801835

RESUMO

As macrolide resistance in Mycoplasma genitalium is increasing worldwide, macrolide resistance-associated mutations should be assessed in M. genitalium-positive specimens. New commercial kits are available for detection of macrolide resistance concurrently with M. genitalium We prospectively evaluated the handling and clinical performances of three commercial kits for detection of macrolide resistance in M. genitalium Between August and December 2018, remnants of all urogenital specimens determined to be M. genitalium positive using an in-house real-time PCR assay were prospectively collected at the French National Reference Center for Bacterial Sexually Transmitted Infections, Bordeaux University Hospital, Bordeaux, France. The internal control of each kit was added to the primary specimen before DNA extraction, and the absence of amplification inhibition associated with the addition of the three internal controls was assessed. Specimens were evaluated with four assays: the ResistancePlus MG assay (SpeeDx), the S-DiaMGRes assay (Diagenode), the RealAccurate TVMGres assay (PathoFinder), and amplification and sequencing of the 23S rRNA gene (the reference assay). Overall, 195 M. genitalium-positive specimens were assessed. The positive agreement of M. genitalium detection for each kit ranged between 94.8% and 96.4%. Among 154 specimens with M. genitalium positivity as detected by the three commercial kits and 23S rRNA sequencing data, the clinical sensitivity and specificity ranges of the three commercial kits for detecting macrolide resistance-associated mutations were 95 to 100% and 94.6 to 97.3%, respectively. The sensitivity and specificity values were similar among the kits. The launch of three easy-to-use sensitive and specific commercial kits for simultaneous detection of M. genitalium and macrolide resistance will be useful for resistance-guided therapy.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana/genética , Macrolídeos/farmacologia , Mycoplasma genitalium/efeitos dos fármacos , Reação em Cadeia da Polimerase em Tempo Real , Feminino , França , Humanos , Masculino , Mutação , Infecções por Mycoplasma/microbiologia , Mycoplasma genitalium/genética , Estudos Prospectivos , RNA Ribossômico 23S/genética , Kit de Reagentes para Diagnóstico , Sensibilidade e Especificidade
19.
Acta Trop ; 203: 105318, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31870709

RESUMO

The serodiagnosis of visceral leishmaniasis (VL) presents problems related to the sensitivity and/or specificity of the tests. In this context, more refined antigens should be identified and applied for the improvement of disease diagnosis. In the present study, DNA with an encoding of a Leishmania infantum hypothetical protein, LiHyC, was cloned, and the recombinant protein was expressed, purified, and evaluated for the serodiagnosis of canine and human VL. In addition, a specific B-cell epitope present in the LiHyC sequence was predicted; the peptide was both synthetized and evaluated in the ELISA experiments. For comparison, commercial diagnostic kits were used against positive (VL hosts) and negative (healthy hosts) samples. Results showed that the recombinant protein (rLiHyC) and synthetic peptide (PeptC) were highly sensitive and specific to diagnose canine and human VL, with 100% sensitivity and specificity, while no false-positive or false-negative result was detected. When the DPP® CVL kit was used to identify canine samples, 44 and 52 of the 60 L. infantum-infected animals, without or with clinical signals of disease, respectively, were identified, while eight and four samples were considered as false-negatives, respectively. For human VL, an IT LEISH® kit was used, and 33 of the 40 VL patients were identified, while seven samples were considered to be false-negatives. Post-therapeutic serological follow-up testing sera samples from treated and untreated VL patients showed a significant drop in the anti-PeptC and anti-rLiHyC antibody levels, thus suggesting the feasibility to use the recombinant protein and/or synthetic peptide in future studies as diagnostic and/or prognostic markers for VL.


Assuntos
Epitopos de Linfócito B/imunologia , Leishmania infantum/imunologia , Leishmaniose Visceral/diagnóstico , Adulto , Animais , Antígenos de Protozoários/imunologia , Cães , Ensaio de Imunoadsorção Enzimática/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Proteínas de Protozoários/imunologia , Proteínas Recombinantes/imunologia , Testes Sorológicos/métodos
20.
Bioanalysis ; 11(7): 645-653, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30993999

RESUMO

Over the last decade, the use of biomarker data has become integral to drug development. Biomarkers are not only utilized for internal decision-making by sponsors; they are increasingly utilized to make critical decisions for drug safety and efficacy. As the regulatory agencies are routinely making decisions based on biomarker data, there has been significant scrutiny on the validation of biomarker methods. Contract research organizations regularly use commercially available immunoassay kits to validate biomarker methods. However, adaptation of such kits in a regulated environment presents significant challenges and was one of the key topics discussed during the 12th Global Contract Research Organization Council for Bioanalysis (GCC) meeting. This White Paper reports the GCC members' opinion on the challenges facing the industry and the GCC recommendations on the classification of commercial kits that can be a win-win for commercial kit vendors and end users.


Assuntos
Bioensaio/métodos , Biomarcadores/análise , Bioensaio/normas , Descoberta de Drogas , Humanos , Ligantes , Preparações Farmacêuticas/química , Preparações Farmacêuticas/metabolismo , Preparações Farmacêuticas/normas , Controle de Qualidade , Kit de Reagentes para Diagnóstico , Padrões de Referência , Sociedades Farmacêuticas , Inquéritos e Questionários
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