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1.
Biosensors (Basel) ; 11(7)2021 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-34201849

RESUMO

The dengue virus (DENV) is a vector-borne flavivirus that infects around 390 million individuals each year with 2.5 billion being in danger. Having access to testing is paramount in preventing future infections and receiving adequate treatment. Currently, there are numerous conventional methods for DENV testing, such as NS1 based antigen testing, IgM/IgG antibody testing, and Polymerase Chain Reaction (PCR). In addition, novel methods are emerging that can cut both cost and time. Such methods can be effective in rural and low-income areas throughout the world. In this paper, we discuss the structural evolution of the virus followed by a comprehensive review of current dengue detection strategies and methods that are being developed or commercialized. We also discuss the state of art biosensing technologies, evaluated their performance and outline strategies to address challenges posed by the disease. Further, we outline future guidelines for the improved usage of diagnostic tools during recurrence or future outbreaks of DENV.


Assuntos
Dengue/diagnóstico , Sistemas Automatizados de Assistência Junto ao Leito , Anticorpos Antivirais , Ensaio de Imunoadsorção Enzimática , Humanos , Imunoglobulina G , Sensibilidade e Especificidade
2.
Medicine (Baltimore) ; 100(27): e26595, 2021 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-34232209

RESUMO

ABSTRACT: Increased neutrophil extracellular trap (NET) formation associates with high cardiovascular risk and mortality in patients with end-stage renal disease (ESRD). However, the effect of transplantation on NETs and its associated markers remains unclear. This study aimed to characterize circulating citrullinated Histone H3 (H3cit) and Peptidyl Arginase Deiminase 4 (PAD4) in ESRD patients undergoing transplantation and evaluate the ability of their neutrophils to release NETs.This prospective cohort study included 80 healthy donors and 105 ESRD patients, out of which 95 received a transplant. H3cit and PAD4 circulating concentration was determined by enzyme-linked immunosorbent assay in healthy donors and ESRD patients at the time of enrollment. An additional measurement was carried out within the first 6 months after transplant surgery. In vitro NET formation assays were performed in neutrophils isolated from healthy donors, ESRD patients, and transplant recipients.H3cit and PAD4 levels were significantly higher in ESRD patients (H3cit, 14.38 ng/mL [5.78-27.13]; PAD4, 3.22 ng/mL [1.21-6.82]) than healthy donors (H3cit, 6.45 ng/mL [3.30-11.65], P < .0001; PAD4, 2.0 ng/mL [0.90-3.18], P = .0076). H3cit, but not PAD4, increased after transplantation, with 44.2% of post-transplant patients exhibiting high levels (≥ 27.1 ng/mL). In contrast, NET release triggered by phorbol 12-myristate 13-acetate was higher in neutrophils from ESRD patients (70.0% [52.7-94.6]) than healthy donors (32.2% [24.9-54.9], P < .001) and transplant recipients (19.5% [3.5-65.7], P < .05).The restoration of renal function due to transplantation could not reduce circulating levels of H3cit and PAD4 in ESRD patients. Furthermore, circulating H3cit levels were significantly increased after transplantation. Neutrophils from transplant recipients exhibit a reduced ability to form NETs.


Assuntos
Armadilhas Extracelulares , Falência Renal Crônica/terapia , Transplante de Rim/métodos , Neutrófilos/patologia , Adulto , Ensaio de Imunoadsorção Enzimática , Feminino , Seguimentos , Humanos , Masculino , Prognóstico , Estudos Prospectivos
3.
Molecules ; 26(13)2021 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-34202190

RESUMO

Background: The disease caused by hepatitis C virus (HCV) is asymptomatic, silent, and progressive liver disease. In HCV-infected patients the increase in serum HA is associated with the development of hepatic fibrosis and disease progression. Methods: HCV-RNA detection was performed in all serological samples of blood donors that tested positive using HCV Ultra ELISA. Determination of hyaluronan (HA) was performed in positive HCV samples using ELISA-like fluorometric method. The HA content was compared to HCV viral load, genotype of the virus, liver fibrosis as well as ALT and GGT liver biomarkers. Results: Persistently normal ALT (<40 U/L) and GGT (<50 U/L) serum levels were detected in 75% and 69% of the HCV-Infected blood donors, respectively. Based on ROC analysis, the HA value < 34.2 ng/mL is an optimal cut-off point to exclude HCV viremia (specificity = 91%, NPV = 99%). Applying HA value ≥34.2 ng/mL significant liver fibrosis (≥F2) can be estimated in 46% of the HCV-infected blood donors. HA serum level (≥34.2 ng/mL) associated with a high ALT level (>40 U/mL) can correctly identify HCV infection and probable liver fibrosis (sensitivity = 96% and specificity = 90%) in asymptomatic blood donors. Conclusions: A high level of HA (≥34.2 ng/mL) in association with ALT (≥40 U/L) in serum can provide a good clinical opportunity to detect HCV-infected asymptomatic persons that potentially require a liver biopsy confirmation and antiviral treatment to prevent the development of advanced liver fibrosis or cirrhosis.


Assuntos
Doadores de Sangue , Hepacivirus/metabolismo , Hepatite C/sangue , Hepatite C/diagnóstico , Ácido Hialurônico/sangue , Cirrose Hepática/sangue , Cirrose Hepática/diagnóstico , Adulto , Ensaio de Imunoadsorção Enzimática , Feminino , Genótipo , Hepacivirus/genética , Hepatite C/genética , Humanos , Cirrose Hepática/genética , Masculino , Pessoa de Meia-Idade
4.
Nat Commun ; 12(1): 4043, 2021 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-34193870

RESUMO

Memory T cells contribute to rapid viral clearance during re-infection, but the longevity and differentiation of SARS-CoV-2-specific memory T cells remain unclear. Here we conduct ex vivo assays to evaluate SARS-CoV-2-specific CD4+ and CD8+ T cell responses in COVID-19 convalescent patients up to 317 days post-symptom onset (DPSO), and find that memory T cell responses are maintained during the study period regardless of the severity of COVID-19. In particular, we observe sustained polyfunctionality and proliferation capacity of SARS-CoV-2-specific T cells. Among SARS-CoV-2-specific CD4+ and CD8+ T cells detected by activation-induced markers, the proportion of stem cell-like memory T (TSCM) cells is increased, peaking at approximately 120 DPSO. Development of TSCM cells is confirmed by SARS-CoV-2-specific MHC-I multimer staining. Considering the self-renewal capacity and multipotency of TSCM cells, our data suggest that SARS-CoV-2-specific T cells are long-lasting after recovery from COVID-19, thus support the feasibility of effective vaccination programs as a measure for COVID-19 control.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , COVID-19/imunologia , Memória Imunológica/imunologia , SARS-CoV-2/imunologia , Anticorpos Antivirais/sangue , Vacinas contra COVID-19/imunologia , Ensaio de Imunoadsorção Enzimática , Humanos , Interferon gama/sangue , Vacinação
5.
Biosensors (Basel) ; 11(6)2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-34203685

RESUMO

In spite of a current increasing trend in the development of miniaturized, standalone point-of-care (PoC) biosensing platforms in the literature, the actual implementation of such systems in the field is far from being a reality although deeply needed. In the particular case of the population screenings for local or regional diseases related to specific pathogens, the diagnosis of the presence of specific antibodies could drastically modify therapies and even the organization of public policies. The aim of this work was to develop a fast, cost-effective detection method based on the manipulation of functionalized magnetic beads for an efficient diagnosis of hypersensitivity pneumonitis (HP), looking for the presence of anti-pigeon antigen antibodies (APAA) in a patient's serum. We presented a Diagnostic Biosensor Method (DBM) in detail, with validation by comparison with a traditional high-throughput platform (ELISA assay). We also demonstrated that it was compatible with a microfluidic chip that could be eventually incorporated into a PoC for easy and broad deployment using portable optical detectors. After standardization of the different reaction steps, we constructed and validated a plastic chip that could easily be scaled to high-volume manufacturing in the future. The solution proved comparable to conventional ELISA assays traditionally performed by the clinicians in their laboratory and should be compatible with other antibody detection directly from patient samples.


Assuntos
Alveolite Alérgica Extrínseca , Técnicas Biossensoriais , Alveolite Alérgica Extrínseca/diagnóstico , Anticorpos , Ensaio de Imunoadsorção Enzimática , Desenho de Equipamento , Humanos , Separação Imunomagnética , Dispositivos Lab-On-A-Chip , Microfluídica , Sistemas Automatizados de Assistência Junto ao Leito
6.
Biosensors (Basel) ; 11(6)2021 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-34205541

RESUMO

A magnetic beads (MB)-involved amperometric immunosensor for the determination of ST2, a member of the IL1 receptor family, is reported in this work. The method utilizes a sandwich immunoassay and disposable screen-printed carbon electrodes (SPCEs). Magnetic immunoconjugates built on the surface of carboxylic acid-microsized magnetic particles (HOOC-MBs) were used to selectively capture ST2. A biotinylated secondary antibody further conjugated with a streptavidin peroxidase conjugate (Strep-HRP) was used to accomplish the sandwiching of the target protein. The immune platform exhibits great selectivity and a low limit of detection (39.6 pg mL-1) for ST2, allowing the determination of soluble ST2 (sST2) in plasma samples from healthy individuals and patients diagnosed with pancreatic ductal adenocarcinoma (PDAC) in only 45 min once the immunoconjugates have been prepared. The good correlation of the obtained results with those provided by an ELISA kit performed using the same immunoreagents demonstrates the potential of the developed strategy for early diagnosis and/or prognosis of the fatal PDAC disease.


Assuntos
Técnicas Biossensoriais , Imunoensaio , Neoplasias/diagnóstico , Anticorpos , Carbono , Técnicas Eletroquímicas , Eletrodos , Ensaio de Imunoadsorção Enzimática , Humanos , Peróxido de Hidrogênio , Limite de Detecção , Magnetismo
7.
Int J Mol Sci ; 22(12)2021 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-34208643

RESUMO

Myosin Light Chain (MLC) regulates platelet contraction through its phosphorylation by Myosin Light Chain Kinase (MLCK) or dephosphorylation by Myosin Light Chain Phosphatase (MLCP). The correlation between platelet contraction force and levels of MLC phosphorylation is unknown. We investigate the relationship between platelet contraction force and MLC phosphorylation using a novel microelectromechanical (MEMS) based clot contraction sensor (CCS). The MLCK and MLCP pair were interrogated by inhibitors and activators of platelet function. The CCS was fabricated from silicon using photolithography techniques and force was validated over a range of deflection for different chip spring constants. The force of platelet contraction measured by the clot contraction sensor (CCS) was compared to the degree of MLC phosphorylation by Western Blotting (WB) and ELISA. Stimulators of MLC phosphorylation produced higher contraction force, higher phosphorylated MLC signal in ELISA and higher intensity bands in WB. Inhibitors of MLC phosphorylation produced the opposite. Contraction force is linearly related to levels of phosphorylated MLC. Direct measurements of clot contractile force are possible using a MEMS sensor platform and correlate linearly with the degree of MLC phosphorylation during coagulation. Measured force represents the mechanical output of the actin/myosin motor in platelets regulated by myosin light chain phosphorylation.


Assuntos
Plaquetas/fisiologia , Sistemas Microeletromecânicos/métodos , Testes de Função Plaquetária/métodos , Algoritmos , Técnicas Biossensoriais , Plaquetas/ultraestrutura , Ensaio de Imunoadsorção Enzimática , Sistemas Microeletromecânicos/instrumentação , Modelos Teóricos , Cadeias Leves de Miosina/metabolismo , Fosforilação , Testes de Função Plaquetária/instrumentação
8.
Cardiovasc Ther ; 2021: 5577218, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34239605

RESUMO

Cellular stress response plays an important role in the pathophysiology of coronary artery disease (CAD). Inhibition of cellular stress may provide a novel clinical approach regarding the diagnosis and treatment of CAD. Fibroblasts constitute 60-70% of cardiac cells and have a crucial role in cardiovascular function. Hence, the aim of this study was to show a potential therapeutic application of proteins derived from heat-stressed fibroblast in CAD patients. Fibroblasts were isolated from the foreskin and cultured under heat stress conditions. Surprisingly, 1.06% of the cells exhibited a necrotic death pattern. Furthermore, heat-stressed fibroblasts produced higher level of total proteins than control cells. In SDS-PAGE analysis, a 70 kDa protein band was observed in stressed cell culture supernatants which appeared as two acidic spots with close pI in the two-dimensional electrophoresis. To evaluate the immunogenic properties of fibroblast-derived heat shock proteins (HSPs), the serum immunoglobulin-G (IgG) was measured by ELISA in 50 CAD patients and 50 normal subjects who had been diagnosed through angiography. Interestingly, the level of anti-HSP antibody was significantly higher in non-CAD individuals in comparison with the patient's group (p < 0.05). The odds ratio for CAD was 5.06 (95%CI = 2.15-11.91) in cut-off value of 30 AU/mL of anti-HSP antibody. Moreover, ROC analysis showed that anti-HSP antibodies had a specificity of 74% and a sensitivity of 64%, which is almost equal to 66% sensitivity of exercise stress test (EST) as a CAD diagnostic method. These data revealed that fibroblast-derived HSPs are suitable for the diagnosis and management of CAD through antibody production.


Assuntos
Doença da Artéria Coronariana/fisiopatologia , Fibroblastos/imunologia , Resposta ao Choque Térmico/imunologia , Idoso , Doença da Artéria Coronariana/sangue , Doença da Artéria Coronariana/imunologia , Ensaio de Imunoadsorção Enzimática , Feminino , Fibroblastos/fisiologia , Proteínas de Choque Térmico/biossíntese , Proteínas de Choque Térmico/imunologia , Resposta ao Choque Térmico/fisiologia , Humanos , Imunoglobulina G/sangue , Masculino , Pessoa de Meia-Idade , Razão de Chances
9.
Rev Bras Parasitol Vet ; 30(3): e004821, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34259738

RESUMO

Canine visceral leishmaniasis (CVL) is a zoonotic disease of high lethality caused by Leishmania infantum in the Americas. In the infected dog, the amastigotes are scarce in blood, especially in the late phase of the disease. This study aimed to report a rare case of L. infantum amastigotes found in neutrophils from peripheral blood of a naturally infected dog in terminal phase of CVL, also describing its clinical status before and after treatment with miltefosine 2%. The dog, which presented as polysymptomatic and with classical signs and symptoms of CVL was submitted to the following tests: Dual Path Platform (DPP) rapid test, ELISA and parasitological examination of peripheral blood. Hematological and biochemical parameters were obtained before and after treatment. All diagnostic tests were positive for CVL. The identification of L. infantum amastigotes inside neutrophils from peripheral blood was confirmed through microscopy, and the species was confirmed by molecular analysis. At the end of the treatment, peripheral parasitemia was not detected, and improvements were observed in clinical and laboratorial parameters. Finally, this atypical finding can be used as example to raise discussions about the real immunological role of neutrophils in late phases of CVL and its clinical/therapeutic implications.


Assuntos
Doenças do Cão , Leishmania infantum , Leishmaniose Visceral , Animais , Doenças do Cão/diagnóstico , Cães , Ensaio de Imunoadsorção Enzimática/veterinária , Leishmaniose Visceral/diagnóstico , Leishmaniose Visceral/veterinária , Neutrófilos
10.
Trop Anim Health Prod ; 53(4): 408, 2021 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-34292411

RESUMO

The study aimed to explore the serum levels of HSP70 and identify its possible association with serum cortisol, thyroid hormones, and acute-phase protein concentrations in cattle naturally infected with foot-and-mouth disease (FMD) virus. After the FMD outbreak in an organized dairy cattle farm in India, blood samples were obtained from clinically infected (n = 40) and apparently healthy (n = 30) animals. Samples were processed and tested by an in-house DIVA assay for confirmation of FMD infection. Serum was analyzed for HSP70, cortisol, T4, T3, haptoglobin, and serum amyloid A by enzyme-linked immunosorbent assay (ELISA). HSP70 concentrations were significantly higher in the serum of clinically infected cattle (p < 0.01) than the healthy group. To the best of our knowledge, this is the first report describing the elevated serum levels of HSP70 under infectious diseases of bovines. Cortisol (p < 0.05), haptoglobin (p < 0.001), and serum amyloid A (p < 0.05) concentrations also markedly increased in the diseased animals; however, no differences (p > 0.05) were found in T4 and T3 levels between healthy and infected cattle. Elevated HSP70 concentration correlated positively with high cortisol (p < 0.05) and haptoglobin (p < 0.001) levels suggesting an essential link between these acute events during clinical infectious phase of FMD.


Assuntos
Doenças dos Bovinos , Vírus da Febre Aftosa , Febre Aftosa , Proteínas de Fase Aguda , Animais , Anticorpos Antivirais , Bovinos , Ensaio de Imunoadsorção Enzimática/veterinária , Hidrocortisona , Índia , Hormônios Tireóideos
11.
Nutrients ; 13(7)2021 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-34209507

RESUMO

CLPB (Caseinolytic peptidase B) protein is a conformational mimetic of α-MSH, an anorectic hormone. Previous in vivo studies have already shown the potential effect of CLPB protein on food intake and on the production of peptide YY (PYY) by injection of E. coli wild type (WT) or E. coli ΔClpB. However, until now, no study has shown its direct effect on food intake. Furthermore, this protein can fragment naturally. Therefore, the aim of this study was (i) to evaluate the in vitro effects of CLPB fragments on PYY production; and (ii) to test the in vivo effects of a CLPB fragment sharing molecular mimicry with α-MSH (CLPB25) compared to natural fragments of the CLPB protein (CLPB96). To do that, a primary culture of intestinal mucosal cells from male Sprague-Dawley rats was incubated with proteins extracted from E. coli WT and ΔCLPB after fragmentation with trypsin or after a heat treatment of the CLPB protein. PYY secretion was measured by ELISA. CLPB fragments were analyzed by Western Blot using anti-α-MSH antibodies. In vivo effects of the CLPB protein on food intake were evaluated by intraperitoneal injections in male C57Bl/6 and ob/ob mice using the BioDAQ® system. The natural CLPB96 fragmentation increased PYY production in vitro and significantly decreased cumulative food intake from 2 h in C57Bl/6 and ob/ob mice on the contrary to CLPB25. Therefore, the anorexigenic effect of CLPB is likely the consequence of enhanced PYY secretion.


Assuntos
Depressores do Apetite/farmacologia , Ingestão de Alimentos/efeitos dos fármacos , Endopeptidase Clp/farmacologia , Proteínas de Escherichia coli/farmacologia , Proteínas de Choque Térmico/farmacologia , Peptídeo YY/metabolismo , Animais , Anticorpos Antibacterianos/metabolismo , Western Blotting , Técnicas de Cultura de Células , Fragmentação do DNA , Ensaio de Imunoadsorção Enzimática , Escherichia coli/química , Injeções Intraperitoneais , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Ratos , Ratos Sprague-Dawley
12.
Analyst ; 146(15): 4905-4917, 2021 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-34250530

RESUMO

We report on the development of surface plasmon resonance (SPR) sensors and matching ELISAs for the detection of nucleocapsid and spike antibodies specific against the novel coronavirus 2019 (SARS-CoV-2) in human serum, plasma and dried blood spots (DBS). When exposed to SARS-CoV-2 or a vaccine against SARS-CoV-2, the immune system responds by expressing antibodies at levels that can be detected and monitored to identify the fraction of the population potentially immunized against SARS-CoV-2 and support efforts to deploy a vaccine strategically. A SPR sensor coated with a peptide monolayer and functionalized with various sources of SARS-CoV-2 recombinant proteins expressed in different cell lines detected human anti-SARS-CoV-2 IgG antibodies in clinical samples. Nucleocapsid expressed in different cell lines did not significantly change the sensitivity of the assays, whereas the use of a CHO cell line to express spike ectodomain led to excellent performance. This bioassay was performed on a portable SPR instrument capable of measuring 4 biological samples within 30 minutes of sample/sensor contact and the chip could be regenerated at least 9 times. Multi-site validation was then performed with in-house and commercial ELISA, which revealed excellent cross-correlations with Pearson's coefficients exceeding 0.85 in all cases, for measurements in DBS and plasma. This strategy paves the way to point-of-care and rapid testing for antibodies in the context of viral infection and vaccine efficacy monitoring.


Assuntos
COVID-19 , SARS-CoV-2 , Anticorpos Antivirais , Vacinas contra COVID-19 , Ensaio de Imunoadsorção Enzimática , Humanos , Imunoglobulina G , Sensibilidade e Especificidade , Glicoproteína da Espícula de Coronavírus , Ressonância de Plasmônio de Superfície
13.
Analyst ; 146(15): 4918-4926, 2021 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-34250990

RESUMO

Antibiotic residues have become the major source of environmental pollutants. In order to monitor tetracycline (TC) in the environment, we have established a highly sensitive and wash-free homogeneous time-resolved immunoassay. This analytical method was based on a rare earth chelate with excellent fluorescence properties. The cryptate organic ligand had good stability and acted as an antenna for Eu3+ excitation. In a homogeneous system, the Eu3+ cryptate complex was used as a label to bind to antibodies. Under the action of immunoaffinity, fluorescent donors and acceptors were close to each other, which induced the FRET effect to produce proportional fluorescence. Under the optimal parameters, the half-inhibitory concentration (IC50) and limit of detection (LOD, IC10) of TC were 0.4188 ng mL-1 and 0.0106 ng mL-1, respectively. The linear range (IC20-IC80) was 0.0273-9.2645 ng mL-1. With the environmental samples, the recovery rate of TC was 84.3-107.2%, and the standard deviation (RSD) was 4.6-12.9%. The results showed the good sensitivity and reliability of the method. Compared with the traditional ELISA, our method has less background interference, only one step was required without the washing procedure, and the detection result can be obtained by 30 min incubation, which improves the detection efficiency. Because of the characteristics of immunoassays, different pollutants can be monitored by changing the antibodies. This method provides an alternative path for detecting environmental pollutants and has the potential to develop into an on-site detection kit.


Assuntos
Antibacterianos , Tetraciclina , Ensaio de Imunoadsorção Enzimática , Imunoensaio , Limite de Detecção , Reprodutibilidade dos Testes
14.
Analyst ; 146(15): 4927-4933, 2021 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-34254081

RESUMO

We prepared monoclonal antibodies (mAbs) against diminazene and used them in the development of a gold nanoparticle-based lateral-flow test (GNT) strip and indirect competitive enzyme-linked immunosorbent assay for the detection of diminazene in beef and beef liver samples. MAbs, which belong to the IgG2a subclass, had a half maximal inhibitory concentration of 0.04 ng mL-1. Based on cross-reactivity, mAb against diminazene was highly specific. The visual limit of detection (vLOD) of the GNT strip was 0.1 µg kg-1, and the cut-off value was 1 µg kg-1 in beef samples. The vLOD of the GNT assay was 0.1 µg kg-1, and the cut-off value was 2 µg kg-1 in beef liver samples. The average recoveries of diminazene ranged from 97.5% to 103.7% when using ic-ELISA. The accuracy of the developed GNT strip was confirmed by comparing the results with the ic-ELISA results. We developed a reliable GNT strip assay for the rapid detection of diminazene in beef and beef liver samples.


Assuntos
Ouro , Nanopartículas Metálicas , Cromatografia de Afinidade , Diminazena , Ensaio de Imunoadsorção Enzimática , Imunoensaio
15.
Wiad Lek ; 74(5): 1134-1136, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34090278

RESUMO

OBJECTIVE: The aim: Of this study was to analyze epidemiological data on the detection of immunoglobulins of class M and G (IgM, IgG) to SARS-CoV-2 among urban and rural population of Poltava region. PATIENTS AND METHODS: Materials and methods: We have analyzed the research results of 2841 patients to determine IgM and IgG levels to SARS-CoV-2. The study included the results of patients in Poltava and nearby villages of Poltava region, obtained during July - December 2020. RESULTS: Results: Thus, 84% of patients applied for detection of IgM in the serum of patients with the pathogen COVID-2019. We have found only 135 positive results for the detection of IgM to SARS-CoV-2, which was 5.7% of the total number of people who underwent this study from July to December 2020. Moreover, women received a positive result more often than men. The IP samples for the detection of IgM to SARS-CoV-2 in the serum of patients averaged 2.5 ± 1.04. It was found that patients went to the laboratory to detect IgG to SARS-CoV-2 with the vast majority among them were residents of Poltava. However, in this case the share of positive results was 47.7%, among which the female population outnumbered the male. CONCLUSION: Conclusions: The frequency of detection of positive results on IgM to SARS-CoV-2 is about 6%. The share of positive results on IgG to SARS-CoV-2 was 47.7%, among them 76.2% were women. The frequency of detection of IgM and IgG to SARS-CoV-2 during October-December 2020 significantly exceeds the indices in July-September of the same year.


Assuntos
COVID-19 , SARS-CoV-2 , Anticorpos Antivirais , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Imunoglobulina G , Imunoglobulina M , Masculino
16.
Bone Joint J ; 103-B(6): 1119-1126, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34058872

RESUMO

AIMS: The aim of this study was to determine the diagnostic accuracy of α defensin (AD) lateral flow assay (LFA) and enzyme-linked immunosorbent assay (ELISA) tests for periprosthetic joint infection (PJI) in comparison to conventional synovial white blood cell (WBC) count and polymorphonuclear neutrophil percentage (PMN%) analysis. METHODS: Patients undergoing joint aspiration for evaluation of pain after total knee arthroplasty (TKA) or total hip arthroplasty (THA) were considered for inclusion. Synovial fluids from 99 patients (25 THA and 74 TKA) were analyzed by WBC count and PMN% analysis, AD LFA, and AD ELISA. WBC and PMN% cutoffs of ≥ 1,700 cells/mm3 and ≥ 65% for TKA and ≥ 3,000 cells/mm3 and ≥ 80% for THA were used, respectively. A panel of three physicians, all with expertise in orthopaedic infections and who were blinded to the results of AD tests, independently reviewed patient data to diagnose subjects as with or without PJI. Consensus PJI classification was used as the reference standard to evaluate test performances. Results were compared using McNemar's test and area under the receiver operating characteristic curve (AUC) analysis. RESULTS: Expert consensus classified 18 arthroplasies as having failed due to PJI and 81 due to aseptic failure. Using these classifications, the calculated sensitivity and specificity of AD LFA was 83.3% (95% confidence interval (CI) 58.6 to 96.4) and 93.8% (95% CI 86.2 to 98.0), respectively. Sensitivity and specificity of AD ELISA was 83.3% (95% CI 58.6 to 96.4) and 96.3% (95% CI 89.6 to 99.2), respectively. There was no statistically significant difference between sensitivity (p = 1.000) or specificity (p = 0.157) of the two AD assays. AUC for AD LFA was 0.891. In comparison, AUC for synovial WBC count, PMN%, and the combination of the two values was 0.821 (sensitivity p = 1.000, specificity p < 0.001), 0.886 (sensitivity p = 0.317, specificity p = 0.011), and 0.926 (sensitivity p = 0.317, specificity p = 0.317), respectively. CONCLUSION: The diagnostic accuracy of synovial AD for PJI diagnosis is comparable and not statistically superior to that of synovial WBC count plus PMN% combined. Cite this article: Bone Joint J 2021;103-B(6):1119-1126.


Assuntos
Contagem de Leucócitos , Neutrófilos , Infecções Relacionadas à Prótese/diagnóstico , Líquido Sinovial/química , alfa-Defensinas/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infecções Relacionadas à Prótese/microbiologia , Sensibilidade e Especificidade
17.
Zhonghua Nei Ke Za Zhi ; 60(6): 539-543, 2021 Jun 01.
Artigo em Chinês | MEDLINE | ID: mdl-34058810

RESUMO

Objective: To determine the seroprevalence of celiac disease in susceptible population, and to analyze the relationship between demographic characteristics, dietary habits, lifestyle and serological positivity so as to provide guidance for the prevention and treatment of celiac disease in Southern China. Methods: A total of 1 273 individuals who participated in Guangdong Province Health Screening Program in 2015, were selected as serologically positive subjects of celiac disease, including people with irritable bowel syndrome, colitis, diarrhea, anemia, low BMI, short stature, type 1 diabetes mellitus (T1DM), rheumatoid arthritis (RA), ankylosing spondylitis, psoriasis and bristol grade=6 or 7. All subjects were tested for serum IgA anti-tissue transglutaminase antibodies (TTGA), IgA antibodies against deamidated gliadin peptides(DGPA) and IgG against deamidated gliadin peptides (DGPG). Dietary habits, lifestyle and demographic characteristics were compared in subgroups. Results: The seroprevalence of celiac disease in susceptible population was 0.94% (95%CI 0.54%-1.64%) including 0.08% (1/1 273) for TTGA, 0.47% (6/1 273) for DGPA, and 0.39% (5/1 273) for DGPG. The seropositive rate was 3.6% (1/28) in patients with psoriasis, 2.1% (2/95) in the low BMI group, 1.9% (1/53) in T1DM group, 1.8% (3/169) in diarrhea group and 1.1% (5/463) in RA group. No significant difference was found in age, gender, high carbohydrate diet or lifestyle between the negative and the positive subjects. Conclusions: In Southern China, the seropositive rate of celiac disease is 0.94% in susceptible population, which prompts an urgent need of serological screening for early diagnosis.


Assuntos
Doença Celíaca , Doença Celíaca/diagnóstico , Doença Celíaca/epidemiologia , China/epidemiologia , Ensaio de Imunoadsorção Enzimática , Gliadina , Humanos , Imunoglobulina G , Estudos Soroepidemiológicos
18.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi ; 37(6): 551-556, 2021 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-34060450

RESUMO

Objective To prepare the fusion protein MVF-ErbB3II composed of measles virus fusion (MVF) protein 288 to 302 amino acid peptide and human epidermal growth factor receptor 3 (ErbB3) 236 to 308 amino acid (ErbB3II) peptide, then prepare and characterize the anti-MVF-ErbB3II polyclonal antibody (pcAb). Methods The MVF-ErbB3II gene was synthesized artificially and subcloned into pET-21b plasmid using DNA ligase. After transformation, the recombinant MVF-ErbB3II protein was expressed in E. coli BL21 (DE3) and purified using nickel ion affinity chromatography. Subsequently, the purified MVF-ErbB3II protein was used as antigen to immunize rats subcutaneously for induction of anti-MVF-ErbB3IIpcAb. The titer of anti-MVF-ErbB3II pcAb was analyzed by ELISA. The ErbB3 specificity and targeting ability of pcAb were evaluated by Western blotting, immunoprecipitation (IP) and flow cytometry (FCM). Results SDS-PAGE confirmed that MVF-ErbB3II protein was successfully expressed and purified. ELISA showed that the titer of pcAb was 1 024 000. Western blotting, IP and FCM assays showed that the anti-MVF-ErbB3II pcAb not only had good antigen specificity against purified MVF-ErbB3II and native ErbB3 but targeted the ErbB3 dimerization interface. Conclusion The prokaryotic expression and purification of MVF-ErbB3II is successfully achieved, rat anti-MVF-ErbB3II pcAb is prepared and characterized successfully.


Assuntos
Escherichia coli , Receptor ErbB-3 , Animais , Especificidade de Anticorpos , Western Blotting , Dimerização , Ensaio de Imunoadsorção Enzimática , Escherichia coli/genética , Ratos , Receptor ErbB-3/genética
19.
Sci Total Environ ; 788: 147789, 2021 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-34134383

RESUMO

INTRODUCTION: Avoidance of inhaled bird antigens is essential to prevent hypersensitivity pneumonitis disease progression. The aim of the present study was to develop a sandwich enzyme link immunoassay (ELISA) and an immunochromatographic test (ICT) and compare their ability to detect pigeon antigens in environmental samples. METHODS: An amplified sandwich ELISA using pigeon serum as a calibration standard and a ICT using gold-labeled anti-pigeon serum antibodies for the rapid detection of pigeon antigens in environmental samples were developed. Twenty-two different airborne samples were collected and analysed using both methods. Strip density values obtained with ICT were calculated and compared with the concentrations determined by the ELISA method for pigeon antigens. Strips results were also visually analysed by five independent evaluators. RESULTS: The ELISA method to quantify pigeon antigen had a broader range (58.4 and 10,112.2 ng/ml), compared to the ICT assay (420 to 3360 ng/ml). A kappa index of 0.736 (p < 0.0001) was obtained between the observers evaluating the ICT strips. The results of the ELISA and the relative density of the ICT showed a highly significant correlation (rs:0.935; p < 0.0001). Bland-Altman plot also confirmed excellent agreement between the two methods (mean difference: -1.626; p < 0.0001). CONCLUSIONS: Since there was a good correlation between both assays, we can conclude that the rapid and simple ICT assay is a good and valid alternative, which does not require expensive equipment, for the validated ELISA technique.


Assuntos
Columbidae , Animais , Cromatografia de Afinidade , Ensaio de Imunoadsorção Enzimática , Imunoensaio , Técnicas Imunoenzimáticas
20.
Egypt J Immunol ; 28(1): 33-45, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34147052

RESUMO

Some studies reported a high prevalence of ischemic stroke in hepatitis C virus patients, other several studies have suggested that hepatitis C virus (HCV) may act as a trigger for autoimmune diseases and autoantibodies including Anti-Neutrophil Cytoplasmic Antibody (ANCA) which predispose to vasculitis. Because vasculitis is a risk factor for ischemic stroke, we investigated the association of the hepatitis C virus with ANCA in first-ever ischemic stroke patients. This study included 67 Egyptian patients with first-ever ischemic stroke. These patients were clinically examined and investigated for HCV infection by chemiluminescence & Real Time-PCR, and ANCA antibodies by ELISA. Forty-two patients (62.7%) had HCV infection. Twenty-nine (43.2%) of them were cytoplasmic- Antineutrophil Cytoplasmic Antibodies (c-ANCA) positive, while none was perinuclear- Antineutrophil Cytoplasmic Antibodies (p-ANCA) positive. Comparison between c-ANCA positive and ANCA negative patients showed that 82.8% and 47.4% had anti-HCV antibody, respectively, with P-value 0.003. The c-ANCA level correlated significantly with age, and HCV antibody level. No statistically significant difference was found in both the consciousness and stroke severity between the negative and positive c- ANCA patients. However, patients with positive c-ANCA had smaller and multiple cerebral infarctions with P-value 0.002 and 0.01 respectively. Multiple regression analysis showed that the number and size of cerebral infarctions were independent predictors of c-ANCA positivity with P value 0.02, and 0.03 respectively. In conclusion, c-ANCA level correlates with HCV antibody and may predispose to ischemic stroke by a possible ANCA associated vasculitis.


Assuntos
Isquemia Encefálica , Hepatite C , AVC Isquêmico , Acidente Vascular Cerebral , Anticorpos Anticitoplasma de Neutrófilos , Isquemia Encefálica/epidemiologia , Egito/epidemiologia , Ensaio de Imunoadsorção Enzimática , Hepacivirus , Hepatite C/complicações , Hepatite C/epidemiologia , Humanos , Acidente Vascular Cerebral/epidemiologia
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