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1.
BJS Open ; 5(4)2021 07 06.
Artículo en Inglés | MEDLINE | ID: mdl-34228096

RESUMEN

BACKGROUND: COVID-19 has brought an unprecedented challenge to healthcare services. The authors' COVID-adapted pathway for suspected bowel cancer combines two quantitative faecal immunochemical tests (qFITs) with a standard CT scan with oral preparation (CT mini-prep). The aim of this study was to estimate the degree of risk mitigation and residual risk of undiagnosed colorectal cancer. METHOD: Decision-tree models were developed using a combination of data from the COVID-adapted pathway (April-May 2020), a local audit of qFIT for symptomatic patients performed since 2018, relevant data (prevalence of colorectal cancer and sensitivity and specificity of diagnostic tools) obtained from literature and a local cancer data set, and expert opinion for any missing data. The considered diagnostic scenarios included: single qFIT; two qFITs; single qFIT and CT mini-prep; two qFITs and CT mini-prep (enriched pathway). These were compared to the standard diagnostic pathway (colonoscopy or CT virtual colonoscopy (CTVC)). RESULTS: The COVID-adapted pathway included 422 patients, whereas the audit of qFIT included more than 5000 patients. The risk of missing a colorectal cancer, if present, was estimated as high as 20.2 per cent with use of a single qFIT as a triage test. Using both a second qFIT and a CT mini-prep as add-on tests reduced the risk of missed cancer to 6.49 per cent. The trade-off was an increased rate of colonoscopy or CTVC, from 287 for a single qFIT to 418 for the double qFIT and CT mini-prep combination, per 1000 patients. CONCLUSION: Triage using qFIT alone could lead to a high rate of missed cancers. This may be reduced using CT mini-prep as an add-on test for triage to colonoscopy or CTVC.


Asunto(s)
COVID-19 , Neoplasias Colorrectales/diagnóstico , Errores Diagnósticos/estadística & datos numéricos , Sangre Oculta , Triaje/organización & administración , Auditoría Clínica , Colonoscopía , Árboles de Decisión , Detección Precoz del Cáncer/métodos , Humanos , Escocia , Sensibilidad y Especificidad , Tomografía Computarizada por Rayos X
2.
Mikrochim Acta ; 188(8): 262, 2021 07 20.
Artículo en Inglés | MEDLINE | ID: mdl-34282508

RESUMEN

COVID-19 is now a severe threat to global health. Facing this pandemic, we developed a space-encoding microfluidic biochip for high-throughput, rapid, sensitive, simultaneous quantitative detection of SARS-CoV-2 antigen proteins and IgG/IgM antibodies in serum. The proposed immunoassay biochip integrates the advantages of graphene oxide quantum dots (GOQDs) and microfluidic chip and is capable of conducting multiple SARS-CoV-2 antigens or IgG/IgM antibodies of 60 serum samples simultaneously with only 2 µL sample volume of each patient. Fluorescence intensity of antigens and IgG antibody detection at emission wavelength of ~680 nm was used to quantify the target concentration at excitation wavelength of 632 nm, and emission wavelength of ~519 nm was used during the detection of IgM antibodies at excitation wavelength of 488 nm. The method developed has a large linear quantification detection regime of 5 orders of magnitude, an ultralow detection limit of ~0.3 pg/mL under optimized conditions, and less than 10-min qualitative detection time. The proposed biosensing platform will not only greatly facilitate the rapid diagnosis of COVID-19 patients, but also provide a valuable screening approach for infected patients, medical therapy, and vaccine recipients.


Asunto(s)
Antígenos Virales/sangre , Inmunoensayo , Inmunoglobulina G/sangre , Inmunoglobulina M/sangre , SARS-CoV-2/aislamiento & purificación , Reacciones Antígeno-Anticuerpo , Antígenos Virales/inmunología , Humanos , Inmunoglobulina G/inmunología , Inmunoglobulina M/inmunología , Nanopartículas/química , Tamaño de la Partícula , SARS-CoV-2/inmunología , Sensibilidad y Especificidad
3.
Proc Natl Acad Sci U S A ; 118(30)2021 07 27.
Artículo en Inglés | MEDLINE | ID: mdl-34244421

RESUMEN

COVID-19 has led to over 3.47 million deaths worldwide and continues to devastate primarily middle- and low-income countries. High-frequency testing has been proposed as a potential solution to prevent outbreaks. However, current tests are not sufficiently low-cost, rapid, or scalable to enable broad COVID-19 testing. Here, we describe LEAD (Low-cost Electrochemical Advanced Diagnostic), a diagnostic test that detects severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) within 6.5 min and costs $1.50 per unit to produce using easily accessible and commercially available materials. LEAD is highly sensitive toward SARS-CoV-2 spike protein (limit of detection = 229 fg⋅mL-1) and displays an excellent performance profile using clinical saliva (100.0% sensitivity, 100.0% specificity, and 100.0% accuracy) and nasopharyngeal/oropharyngeal (88.7% sensitivity, 86.0% specificity, and 87.4% accuracy) samples. No cross-reactivity was detected with other coronavirus or influenza strains. Importantly, LEAD also successfully diagnosed the highly contagious SARS-CoV-2 B.1.1.7 UK variant. The device presents high reproducibility under all conditions tested and preserves its original sensitivity for 5 d when stored at 4 °C in phosphate-buffered saline. Our low-cost and do-it-yourself technology opens new avenues to facilitate high-frequency testing and access to much-needed diagnostic tests in resource-limited settings and low-income communities.


Asunto(s)
Técnicas Biosensibles , Prueba de COVID-19 , COVID-19 , Grafito/química , SARS-CoV-2/metabolismo , Glicoproteína de la Espiga del Coronavirus/metabolismo , COVID-19/diagnóstico , COVID-19/metabolismo , Electrodos , Humanos , Sensibilidad y Especificidad
4.
Sci Rep ; 11(1): 14204, 2021 07 09.
Artículo en Inglés | MEDLINE | ID: mdl-34244543

RESUMEN

The pandemic of 2019 caused by the novel coronavirus (SARS-CoV-2) is still rapidly spreading worldwide. Nucleic acid amplification serves as the gold standard method for confirmation of COVID-19 infection. However, challenges faced for diagnostic laboratories from undeveloped countries includes shortage of kits and supplies to purify viral RNA. Therefore, it is urgent to validate alternative nucleic acid isolation methods for SARS-CoV-2. Our results demonstrate that a concentrated viral lysis amplification buffer (vLAB) prepared with the nonionic detergent IGEPAL enables qualitative detection of SARS-CoV-2 by direct Reverse Transcriptase-Polymerase Chain Reaction (dRT-PCR). Furthermore, vLAB was effective in inactivating SARS-CoV-2. Since this method is inexpensive and no RNA purification equipment or additional cDNA synthesis is required, this dRT-PCR with vLAB should be considered as an alternative method for qualitative detection of SARS-CoV-2.


Asunto(s)
Prueba de Ácido Nucleico para COVID-19 , COVID-19 , ARN Viral/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , SARS-CoV-2/genética , Manejo de Especímenes , COVID-19/diagnóstico , COVID-19/genética , Humanos , Sensibilidad y Especificidad
5.
Biosensors (Basel) ; 11(7)2021 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-34201849

RESUMEN

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.


Asunto(s)
Dengue/diagnóstico , Sistemas de Atención de Punto , Anticuerpos Antivirales , Ensayo de Inmunoadsorción Enzimática , Humanos , Inmunoglobulina G , Sensibilidad y Especificidad
6.
Int J Mol Sci ; 22(13)2021 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-34202199

RESUMEN

In this review, the unique properties of intrinsically conducting polymer (ICP) in biomedical engineering fields are summarized. Polythiophene and its valuable derivatives are known as potent materials that can broadly be applied in biosensors, DNA, and gene delivery applications. Moreover, this material plays a basic role in curing and promoting anti-HIV drugs. Some of the thiophene's derivatives were chosen for different experiments and investigations to study their behavior and effects while binding with different materials and establishing new compounds. Many methods were considered for electrode coating and the conversion of thiophene to different monomers to improve their functions and to use them for a new generation of novel medical usages. It is believed that polythiophenes and their derivatives can be used in the future as a substitute for many old-fashioned ways of creating chemical biosensors polymeric materials and also drugs with lower side effects yet having a more effective response. It can be noted that syncing biochemistry with biomedical engineering will lead to a new generation of science, especially one that involves high-efficiency polymers. Therefore, since polythiophene can be customized with many derivatives, some of the novel combinations are covered in this review.


Asunto(s)
Materiales Biocompatibles/química , Técnicas Biosensibles , ADN/análisis , Polímeros/química , Tiofenos/química , Fármacos Anti-VIH/química , Fármacos Anti-VIH/farmacología , Materiales Biocompatibles Revestidos/química , Técnicas Electroquímicas , Electrodos , Microscopía de Fuerza Atómica , Sensibilidad y Especificidad , Tiofenos/farmacología
7.
Pediatr Infect Dis J ; 40(8): e300-e304, 2021 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-34250969

RESUMEN

BACKGROUND: Saliva reverse transcriptase-Polymerase chain reaction (RT-PCR) is an attractive alternative for the detection of severe acute respiratory syndrome coronavirus 2 in adults with less known in children. METHODS: Children with coronavirus disease 2019 symptoms were prospectively enrolled in a 1-month comparative clinical trial of saliva and nasopharyngeal (NP) RT-PCR. Detection rates and sensitivities of saliva and NP RT-PCR were compared as well as discordant NP and saliva RT-PCR findings including viral loads (VLs). RESULTS: Of 405 patients enrolled, 397 patients had 2 tests performed. Mean age was 12.7 years (range, 1.2-17.9). Sensitivity of saliva was 85.2% (95% confidence interval: 78.2%-92.1%) when using NP as the standard; sensitivity of NP was 94.5% (89.8%-99.2%) when saliva was considered as the standard. For a NP RT-PCR VL threshold of ≥103 and ≥104 copies/mL, sensitivity of saliva increases to 88.7% and 95.2%, respectively. Sensitivity of saliva and NP swabs was, respectively, 89.5% and 95.3% in patient with symptoms less than 4 days (P = 0.249) and 70.0% and 95.0% in those with symptoms ≥4-7 days (P = 0.096). The 15 patients who had an isolated positive NP RT-PCR were younger (P = 0.034), had lower NP VL (median 5.6 × 103 vs. 3.9 × 107, P < 0.001), and could not drool saliva at the end of the sampling (P = 0.002). VLs were lower with saliva than with NP RT-PCR (median 8.7 cp/mL × 104; interquartile range 1.2 × 104-5.2 × 105; vs. median 4.0 × 107 cp/mL; interquartile range, 8.6 × 105-1 × 108; P < 0.001). CONCLUSIONS: While RT-PCR testing on saliva performed more poorly in younger children and likely after longer duration of symptoms, saliva remains an attractive alternative to NP swabs in children.


Asunto(s)
Prueba de COVID-19 , COVID-19/diagnóstico , COVID-19/virología , Nasofaringe/virología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , SARS-CoV-2/aislamiento & purificación , Saliva/virología , Niño , Preescolar , Pruebas Diagnósticas de Rutina , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Estudios Prospectivos , SARS-CoV-2/genética , Sensibilidad y Especificidad , Manejo de Especímenes , Carga Viral
9.
Int J Nanomedicine ; 16: 4739-4753, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34267520

RESUMEN

Background: Serological tests detecting severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) are widely used in seroprevalence studies and evaluating the efficacy of the vaccination program. Some of the widely used serological testing techniques are enzyme-linked immune-sorbent assay (ELISA), chemiluminescence immunoassay (CLIA), and lateral flow immunoassay (LFIA). However, these tests are plagued with low sensitivity or specificity, time-consuming, labor-intensive, and expensive. We developed a serological test implementing flow-through dot-blot assay (FT-DBA) for SARS-CoV-2 specific IgG detection, which provides enhanced sensitivity and specificity while being quick to perform and easy to use. Methods: SARS-CoV-2 antigens were immobilized on nitrocellulose membrane to capture human IgG, which was then detected with anti-human IgG conjugated gold nanoparticle (hIgG-AuNP). A total of 181 samples were analyzed in-house. Within which 35 were further evaluated in US FDA-approved CLIA Elecsys SARS-CoV-2 assay. The positive panel consisted of RT-qPCR positive samples from patients with both <14 days and >14 days from the onset of clinical symptoms. The negative panel contained samples collected from the pre-pandemic era dengue patients and healthy donors during the pandemic. Moreover, the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of FT-DBA were evaluated against RT-qPCR positive sera. However, the overall efficacies were assessed with sera that seroconverted against either nucleocapsid (NCP) or receptor-binding domain (RBD). Results: In-house ELISA selected a total of 81 true seropositive and 100 seronegative samples. The sensitivity of samples with <14 days using FT-DBA was 94.7%, increasing to 100% for samples >14 days. The overall detection sensitivity and specificity were 98.8% and 98%, respectively, whereas the overall PPV and NPV were 99.6% and 99%. Moreover, comparative analysis between in-house ELISA assays and FT-DBA revealed clinical agreement of Cohen's Kappa value of 0.944. The FT-DBA showed sensitivity and specificity of 100% when compared with commercial CLIA kits. Conclusion: The assay can confirm past SARS-CoV-2 infection with high accuracy within 2 minutes compared to commercial CLIA or in-house ELISA. It can help track SARS-CoV-2 disease progression, population screening, and vaccination response. The ease of use of the assay without requiring any instruments while being semi-quantitative provides the avenue of its implementation in remote areas around the globe, where conventional serodiagnosis is not feasible.


Asunto(s)
Oro/química , Immunoblotting/métodos , Inmunoglobulina G/análisis , Nanopartículas del Metal/química , Nucleocápside/análisis , SARS-CoV-2/aislamiento & purificación , Adulto , Anticuerpos Antivirales/sangre , Humanos , Inmunoglobulina G/sangre , Inmunoglobulina G/inmunología , Masculino , Valor Predictivo de las Pruebas , SARS-CoV-2/inmunología , Sensibilidad y Especificidad , Estudios Seroepidemiológicos
10.
Int J Mol Sci ; 22(11)2021 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-34200331

RESUMEN

The coronavirus disease 2019 (COVID-19) has caused a large global outbreak. It is accordingly important to develop accurate and rapid diagnostic methods. The polymerase chain reaction (PCR)-based method including reverse transcription-polymerase chain reaction (RT-PCR) is the most widely used assay for the detection of SARS-CoV-2 RNA. Along with the RT-PCR method, digital PCR has emerged as a powerful tool to quantify nucleic acid of the virus with high accuracy and sensitivity. Non-PCR based techniques such as reverse transcription loop-mediated isothermal amplification (RT-LAMP) and reverse transcription recombinase polymerase amplification (RT-RPA) are considered to be rapid and simple nucleic acid detection methods and were reviewed in this paper. Non-conventional molecular diagnostic methods including next-generation sequencing (NGS), CRISPR-based assays and nanotechnology are improving the accuracy and sensitivity of COVID-19 diagnosis. In this review, we also focus on standardization of SARS-CoV-2 nucleic acid testing and the activity of the National Metrology Institutes (NMIs) and highlight resources such as reference materials (RM) that provide the values of specified properties. Finally, we summarize the useful resources for convenient COVID-19 molecular diagnostics.


Asunto(s)
Prueba de Ácido Nucleico para COVID-19/métodos , COVID-19/diagnóstico , Técnicas de Amplificación de Ácido Nucleico/métodos , SARS-CoV-2/aislamiento & purificación , Animales , COVID-19/virología , Sistemas CRISPR-Cas , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Técnicas de Diagnóstico Molecular , Nanotecnología , Reacción en Cadena de la Polimerasa , ARN Viral , Recombinasas , Transcripción Reversa , Sensibilidad y Especificidad
11.
Int J Mol Sci ; 22(13)2021 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-34206928

RESUMEN

Brush-like α-Fe2O3-ZnO heterostructures were synthesized through a sputtering ZnO seed-assisted hydrothermal growth method. The resulting heterostructures consisted of α-Fe2O3 rod templates and ZnO branched crystals with an average diameter of approximately 12 nm and length of 25 nm. The gas-sensing results demonstrated that the α-Fe2O3-ZnO heterostructure-based sensor exhibited excellent sensitivity, selectivity, and stability toward low-concentration NO2 gas at an optimal temperature of 300 °C. The α-Fe2O3-ZnO sensor, in particular, demonstrated substantially higher sensitivity compared with pristine α-Fe2O3, along with faster response and recovery speeds under similar test conditions. An appropriate material synergic effect accounts for the considerable enhancement in the NO2 gas-sensing performance of the α-Fe2O3-ZnO heterostructures.


Asunto(s)
Compuestos Férricos/química , Nanoestructuras/química , Dióxido de Nitrógeno/análisis , Óxido de Zinc/química , Técnicas de Química Analítica/métodos , Dióxido de Nitrógeno/química , Sensibilidad y Especificidad
12.
J Biol Regul Homeost Agents ; 35(3): 881-887, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34231353

RESUMEN

Since the spreading of Sar-CoV-2 in March 2020, many serologic tests have been developed to identify antibody responses. Indeed, different commercial kits are directed against different antigens and could utilise different methods thereby triggering confusion and criticism. Here, we compared two Food and Drug Administration (FDA)-approved automatized assays that detect IgG responses against spike or nucleocapsid protein of Sars-Cov-2 virus in 127 subjects among healthcare workers of IRCCS Policlinico San Donato (MI), Italy. We observed different kinetics of IgG responses, demonstrating the importance of timing of sampling to correctly interpret the results both for infection diagnosis and for epidemiologic studies. We observed that Anti-N response starts earlier than Anti-S1/S2 response but also decreases earlier, affecting the sensitivity of the tests at different time points. Combining two different assays, designed against different antigens, could reduce false negative results. Finally, we observed a patient who produced anti-nucleocapsid IgG, but not anti-spike IgG. In conclusion, we investigated antibody responses in Covid-19 disease, aiming to direct clinicians and laboratory scientists to correctly interpret serologic results by always paying attention to clinical history correlation, timing of sampling, methods and antigens used, to avoid false negative results and obtain relevant epidemiologic data.


Asunto(s)
COVID-19 , Anticuerpos Antivirales , Humanos , Inmunoglobulina G , Italia , SARS-CoV-2 , Sensibilidad y Especificidad , Glicoproteína de la Espiga del Coronavirus , Estados Unidos
13.
Ann Palliat Med ; 10(6): 6753-6759, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34237975

RESUMEN

BACKGROUND: Placenta previa is one dangerous disease which threatens the health of pregnant women and their fetuses. The purpose of this study was to evaluate the clinical value of ultrasound combined with magnetic resonance imaging (MRI) in screening for placenta previa complicated by placenta accreta. METHODS: Seventy patients with abnormal fetal position admitted to our hospital from January 2019 to January 2020 were selected for the study. Patients were diagnosed by ultrasound alone, MRI alone, and ultrasound combined with MRI. Diagnostic accuracy, sensitivity, specificity and false positive and negative diagnosis rates were evaluated against the postoperative pathological examinations of the patients. RESULTS: The diagnostic accuracy, sensitivity and false negative rate for ultrasound combined with MRI were 86.27%, 97.78% and 72.00%, respectively. These results were significantly superior to those of MRI or ultrasound alone (P<0.05). The specificity and false positive rate for ultrasound combined with MRI were 13.73% and 5.26%, respectively, which were not significantly different from those for MRI or ultrasound alone (P>0.05). CONCLUSIONS: Compared with ultrasound or MRI alone, ultrasound combined with MRI has higher accuracy and sensitivity in the diagnosis of placenta previa with placenta accreta, along with lower false positive diagnosis rates. These findings are clinically important for improving the diagnostic efficiency.


Asunto(s)
Placenta Accreta , Placenta Previa , Femenino , Humanos , Imagen por Resonancia Magnética , Placenta Accreta/diagnóstico por imagen , Placenta Previa/diagnóstico por imagen , Embarazo , Estudios Retrospectivos , Sensibilidad y Especificidad , Ultrasonografía
14.
Ann Palliat Med ; 10(6): 6850-6858, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34237982

RESUMEN

BACKGROUND: Salmonella enterica is a zoonotic pathogen of substantial concern to human and animal health and is a leading cause of morbidity and mortality in people worldwide. Loop-mediated isothermal amplification (LAMP) technology is a new type of nucleic acid amplification technology, which has the characteristics of high specificity, high sensitivity, simple operation, convenience, and low cost. This study aims to establish a rapid detection method for Salmonella based on LAMP technology. METHODS: Primers were designed for Salmonella's specific conservative invA gene. Through primer screening and optimization of reaction conditions, and a LAMP method for detecting Salmonella with real-time fluorescence and visual observation results was established. The sensitivity and specificity of the method were assessed, and the accuracy was evaluated through the testing of Salmonella-contaminated and non-contaminated clinical samples. RESULTS: The optimal reaction temperature of LAMP was 60-65 °C, and the optimal reaction time was 25-30 minutes. The detection limits of real-time fluorescence and visual observation were both 1.4 pg/µL. There was no cross-reactivity observed with 22 non-Salmonella species, and the specificity was 100%. Additionally, 30 samples contaminated with Salmonella, 30 samples not contaminated with Salmonella, and 8 clinical samples identified as positive by bacterial culture and microbial mass spectrometry were tested. The positive coincidence rate of the detection system was 97.4% by real-time fluorescence and 89.5% by visual observation, the negative coincidence rate was 100%, and the total coincidence rate was 98.5% and 94.1%, respectively. CONCLUSIONS: In the scene of infection, primary hospital, disaster area treatment and other scenarios, the conditions of environment, equipment and personnel was limited, therefore, the established real-time fluorescence and visual lamp method can provide a powerful means for the rapid detection of Salmonella.


Asunto(s)
Técnicas de Amplificación de Ácido Nucleico , Salmonella , Animales , Humanos , Técnicas de Diagnóstico Molecular , Salmonella/genética , Sensibilidad y Especificidad
15.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 43(3): 406-413, 2021 Jun 30.
Artículo en Chino | MEDLINE | ID: mdl-34238417

RESUMEN

Objective To evaluate the diagnostic performance of 1.5-T non-contrast free-breathing whole-heart magnetic resonance coronary angiography(MRCA)for≥50% and≥70% coronary artery stenosis in coronary artery disease(CAD).Methods Forty-one patients clinically scheduled for invasive coronary angiography(ICA)underwent 1.5-T non-contrast free-breathing whole-heart MRCA.The diagnostic performance for≥50% and≥70% stenosis was evaluated and compared using ICA as a reference standard.Results MRCA was completed in all the 41 patients with the total acquisition time of(10.1 ± 2.2)min.The sensitivity,specificity,and accuracy of MRCA for≥50% and≥70% stenosis were 100%(95% CI:89%-100%)and 82%(95%CI:63%-94%),38%(95%CI:9%-76%)and 54%(95%CI:25%-81%),and 88%(95%CI:73%-95%)and 73%(95%CI:57%-85%)on a per-patient basis,respectively;they were 95%(95%CI:87%-99%)and 86%(95%CI:73%-95%),58%(95%CI:45%-71%)and 76%(95%CI:65%-85%),and 78%(95%CI:69%-84%)and 80%(95%CI:71%-86%)on a per-vessel basis,respectively.The sensitivity of MRCA for≥50% stenosis was higher than that for≥70% stenosis(97%vs.88%,χ 2=5.73,P=0.017),and the specificity showed an opposite trend(86% vs. 94%,χ 2=14.12,P<0.001)on a per-segment basis.Conclusions The 1.5-T non-contrast whole-heart MRCA can detect both≥50% and≥70% coronary artery stenosis with high sensitivity and accuracy.MRCA showed lower sensitivity while higher specificity for≥70% stenosis than for≥50% stenosis on a per-segment basis.


Asunto(s)
Estenosis Coronaria , Angiografía Coronaria , Estenosis Coronaria/diagnóstico por imagen , Humanos , Angiografía por Resonancia Magnética , Espectroscopía de Resonancia Magnética , Valor Predictivo de las Pruebas , Sensibilidad y Especificidad
16.
Acta Derm Venereol ; 101(7): adv00498, 2021 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-34219175

RESUMEN

In the absence of guidelines recommending routine total-body skin examination, patient concern remains the main factor in seeking consultation regarding suspicion of skin cancer. This study explores gaps in patients' understanding of malignant skin lesions, through the factors associated with incidental skin cancer. Included patients had a confirmed histological diagnosis of basal cell carci-noma, squamous cell carcinoma or melanoma. Tumour characteristics, patient demographics and other risk factors related to the development of skin cancer were obtained from each participant. The main measure was incidental skin cancer detection, using both binary logistic regression and Chi-squared Automatic Interaction Detection (CHAID) algorithm. Of the total tumours, 26.6% were detected incidentally. The following variables: male sex, living alone, long-axis diameter, tumour location, symptoms and time of disease evolution were independent predictors of incidental skin cancer. According to the CHAID algorithm, the most significant risk factor for incidental skin cancer was the absence of symptoms at diagnosis.


Asunto(s)
Carcinoma Basocelular , Melanoma , Neoplasias Cutáneas , Carcinoma Basocelular/diagnóstico , Carcinoma Basocelular/epidemiología , Humanos , Masculino , Melanoma/diagnóstico , Melanoma/epidemiología , Estudios Prospectivos , Sensibilidad y Especificidad , Neoplasias Cutáneas/diagnóstico , Neoplasias Cutáneas/epidemiología
17.
BMC Infect Dis ; 21(1): 665, 2021 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-34238234

RESUMEN

BACKGROUND: As SARS-CoV-2 testing expands, particularly to widespread asymptomatic testing, high sensitivity point-of-care PCR platforms may optimise potential benefits from pooling multiple patients' samples. METHOD: We tested patients and asymptomatic citizens for SARS-CoV-2, exploring the efficiency and utility of CovidNudge (i) for detection in individuals' sputum (compared to nasopharyngeal swabs), (ii) for detection in pooled sputum samples, and (iii) by modelling roll out scenarios for pooled sputum testing. RESULTS: Across 295 paired samples, we find no difference (p = 0.1236) in signal strength for sputum (mean amplified replicates (MAR) 25.2, standard deviation (SD) 14.2, range 0-60) compared to nasopharyngeal swabs (MAR 27.8, SD 12.4, range 6-56). At 10-sample pool size we find some drop in absolute strength of signal (individual sputum MAR 42.1, SD 11.8, range 13-60 vs. pooled sputum MAR 25.3, SD 14.6, range 1-54; p < 0.0001), but only marginal drop in sensitivity (51/53,96%). We determine a limit of detection of 250 copies/ml for an individual test, rising only four-fold to 1000copies/ml for a 10-sample pool. We find optimal pooled testing efficiency to be a 12-3-1-sample model, yet as prevalence increases, pool size should decrease; at 5% prevalence to maintain a 75% probability of negative first test, 5-sample pools are optimal. CONCLUSION: We describe for the first time the use of sequentially dipped sputum samples for rapid pooled point of care SARS-CoV-2 PCR testing. The potential to screen asymptomatic cohorts rapidly, at the point-of-care, with PCR, offers the potential to quickly identify and isolate positive individuals within a population "bubble".


Asunto(s)
Prueba de COVID-19/métodos , COVID-19/diagnóstico , COVID-19/virología , Pruebas en el Punto de Atención , SARS-CoV-2/aislamiento & purificación , Esputo/virología , Pruebas Diagnósticas de Rutina , Humanos , Límite de Detección , Nasofaringe/virología , Sensibilidad y Especificidad , Carga Viral
18.
J Healthc Eng ; 2021: 5513679, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34194681

RESUMEN

The world is experiencing an unprecedented crisis due to the coronavirus disease (COVID-19) outbreak that has affected nearly 216 countries and territories across the globe. Since the pandemic outbreak, there is a growing interest in computational model-based diagnostic technologies to support the screening and diagnosis of COVID-19 cases using medical imaging such as chest X-ray (CXR) scans. It is discovered in initial studies that patients infected with COVID-19 show abnormalities in their CXR images that represent specific radiological patterns. Still, detection of these patterns is challenging and time-consuming even for skilled radiologists. In this study, we propose a novel convolutional neural network- (CNN-) based deep learning fusion framework using the transfer learning concept where parameters (weights) from different models are combined into a single model to extract features from images which are then fed to a custom classifier for prediction. We use gradient-weighted class activation mapping to visualize the infected areas of CXR images. Furthermore, we provide feature representation through visualization to gain a deeper understanding of the class separability of the studied models with respect to COVID-19 detection. Cross-validation studies are used to assess the performance of the proposed models using open-access datasets containing healthy and both COVID-19 and other pneumonia infected CXR images. Evaluation results show that the best performing fusion model can attain a classification accuracy of 95.49% with a high level of sensitivity and specificity.


Asunto(s)
COVID-19/diagnóstico por imagen , Aprendizaje Profundo , Interpretación de Imagen Radiográfica Asistida por Computador/métodos , Radiografía Torácica/métodos , Humanos , Pulmón/diagnóstico por imagen , SARS-CoV-2 , Sensibilidad y Especificidad
19.
J Contemp Dent Pract ; 22(4): 365-372, 2021 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-34267005

RESUMEN

AIM AND OBJECTIVE: This study was conducted to evaluate the accuracy of a light-induced fluorescence intraoral camera vs the visual-tactile assessment method according to the modified International caries detection and assessment system-II (ICDAS-II) criteria clinically in the detection of initial occlusal caries. MATERIALS AND METHODS: Occlusal surfaces of 260 molar and premolar teeth from 52 adult participants were examined by two calibrated observers, using two diagnostic methods. Teeth were initially assessed visually according to the criteria of the ICDAS-II, and then by fluorescence camera (Soprolife®). Inter- and intraobserver agreements were measured using Cohen's kappa test. Correlation between methods was calculated using Wilcoxon signed-rank test, and effect size for comparison between the two modalities. The sensitivity, specificity, predictive values, diagnostic accuracy, likelihood ratios (LRs), area under the receiver operating characteristic (ROC) curve (AUC), and 95% confidence interval (95% CI) of the AUC for caries detection by Soprolife® were evaluated. RESULTS: A significant positive correlation was found between the ICDAS-II and camera measurements (p-value <0.001, effect size = 0.572). The sensitivity of Soprolife® was 94.2%, specificity 84.2%, positive predictive value 87.1%, negative predictive value 92.8%, positive LR 6%, negative LR 0.07%, and the diagnostic accuracy 89.5%. AUC was 0.909 with 95% CI (0.863-0.955). There was a perfect intraobserver agreement (kappa = 1.00) for both testing modalities. There was moderate interobserver agreement (kappa = 0.520) with regards to ICDAS, while for Soprolife®, there was substantial interobserver agreement (kappa = 0.798). CONCLUSION: Soprolife® can be used as a valid and reliable assessment tool for occlusal caries detection. CLINICAL SIGNIFICANCE: Light-induced fluorescence intraoral camera is an efficient tool in the detection of initial occlusal caries.


Asunto(s)
Caries Dental , Diente , Adulto , Caries Dental/diagnóstico , Susceptibilidad a Caries Dentarias , Fluorescencia , Humanos , Diente Molar , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
20.
Artículo en Inglés | MEDLINE | ID: mdl-34200827

RESUMEN

BACKGROUND AND AIMS: Quick and reliable diagnostic tools play an important role in controlling the spread of the SARS-Cov-2 pandemic. The aim of this study was to evaluate the diagnostic accuracy of a new cyto-salivary antigen test aimed at detecting the presence of antigens for SARS-CoV-2, as compared by the gold standard RT-PCR and a lateral flow test. METHODS: A total of 433 healthy volunteers were enrolled in the study and the sensitivity and specificity of the new cyto-salivary antigen test were calculated, as compared to the RT-PCR nasopharyngeal swab and to the lateral flow test. RESULTS: A total of 433 samples were collected and tested at the Mediterranean Fair in Palermo from February 2021 until April 2021. The new cyto-salivary antigen had a sensitivity of 100% and a specificity of 94.2%. The sensitivity and the specificity of the lateral flow test were 55% and 100%, respectively. CONCLUSIONS: The new cyto-salivary antigen test detected more positive cases than the RT-PCR in a sample of asymptomatic subjects, demonstrating to be a promising tool for a more sensitive diagnosis of COVID-19. Further studies are warranted to better characterize its diagnostic accuracy.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , Pruebas Inmunológicas , Pandemias , Sensibilidad y Especificidad
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