Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 10.539
Filtrar
1.
Indian J Med Res ; 151(2 & 3): 210-215, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32362646

RESUMEN

Background & objectives: Nearly 5,500 tests for coronavirus disease 2019 (COVID-19) had been conducted on March 31, 2020 across the Indian Council of Medical Research (ICMR)-approved public and private laboratories in India. Given the need to rapidly increase testing coverage, we undertook an exercise to explore and quantify interventions to increase the daily real-time reverse transcription-polymerase chain reaction (qRT-PCR)-based testing capacity over the next few months. The objective of this exercise was to prepare a potential plan to scale-up COVID-19 testing in India in the public sector. Methods: Potential increase in daily testing capacity of the existing public laboratories was calculated across the three base scenarios of shifts (9, 16 and 24 h). Additional testing capacity was added for each shift scenario based on interventions ranging from procurement of additional qRT-PCR machines, leveraging spare capacity on available qRT-PCR machines not drafted into COVID-19 testing, to in-laboratory process optimization efforts. Results: Moving to a 24 h working model in the existing approved laboratories can enhance the daily testing capacity to 40,464 tests/day. The capacity can be further bolstered by leveraging qRT-PCR and nucleic acid amplification test (NAAT)-based machines available with the Multidisciplinary Research Units (MRUs), National AIDS Control Organisation (NACO) and National Tuberculosis Elimination Programme (NTEP). Using combination/multiplex kits, and provision of automated RNA extraction platforms at all laboratories could also optimize run time and contribute to capacity increase by 1.5-2 times. Interpretation & conclusions: Adopting these interventions could help increase public sector's daily testing capacity to nearly 100,000-120,000 tests/day. It is important to note that utilization of the scaled-up testing capacity will require deployment of additional workforce, procurement of corresponding commodities for testing and scale-up of sample collection and transportation efforts.


Asunto(s)
Infecciones por Coronavirus/diagnóstico , Neumonía Viral/diagnóstico , Planificación Estratégica , Automatización de Laboratorios , Betacoronavirus , Técnicas de Laboratorio Clínico , Ensayos Analíticos de Alto Rendimiento , Humanos , India , Técnicas de Amplificación de Ácido Nucleico , Pandemias , Sector Público , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
2.
Int J Mol Sci ; 21(9)2020 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-32370065

RESUMEN

In this work, hybridization chain reactions (HCRs) toward Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) nucleocapsid phosphoproteins gene loci and human RNase P are proposed to provide an isothermal amplification screening tool. The proposed chain reactions target the complementary DNA (cDNA) of SARS-CoV-2, with loci corresponding to gold-standard polymerase chain reaction (PCR) loci. Four hybridization chain reaction reactions are demonstrated herein, targeting N1/N2/N3 loci and human RNase P. The design of the hybridization chain reaction, herein, is assisted with an algorithm. The algorithm helps to search target sequences with low local secondary structure and high hybridization efficiency. The loop domain of the fuel hairpin molecule H1 and H2, which are the tunable segments in such reactions, are used as an optimization parameter to improve the hybridization efficiency of the chain reaction. The algorithm-derived HCR reactions were validated with gel electrophoresis. All proposed reactions exhibit a hybridization complex with a molecular mass >1.5k base pairs, which is clear evidence of chain reaction. The hybridization efficiency trend revealed by gel electrophoresis corresponds nicely to the simulated data from the algorithm. The HCR reactions and the corresponding algorithm serve as a basis to further SARS-CoV-2 sensing applications and facilitate better screening strategies for the prevention of on-going pandemics.


Asunto(s)
Betacoronavirus/genética , Betacoronavirus/aislamiento & purificación , Infecciones por Coronavirus/diagnóstico , Tamizaje Masivo/métodos , Técnicas de Amplificación de Ácido Nucleico/métodos , Neumonía Viral/diagnóstico , Simulación por Computador , Infecciones por Coronavirus/virología , ADN Complementario/genética , Humanos , Pandemias , Neumonía Viral/virología , Reacción en Cadena de la Polimerasa/métodos , Ribonucleasa P/genética
3.
J Biomed Nanotechnol ; 16(2): 166-178, 2020 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-32252878

RESUMEN

White root rot (WRR) disease caused by Rosellinia necatrix, a fungal pathogen, results in severe damage to various fruit trees, decreasing their marketability. Regular monitoring is a major process because the pathogen can remain in the soil around the host for a long time. Loop-mediated isothermal amplification (LAMP) is a highly sensitive and efficient amplification technology of nucleic acids (DNA or RNA) that can be performed at constant temperatures. Thus, it has been spotlighted as a useful tool for detecting several infectious agents. In the present study, LAMP-based Turn-on Fluorescent Paper (ToFP) devices were designed and applied to detect R. necatrix. LAMP conditions were optimized and found to be optimal at a reaction temperature (62 °C) and a reaction time (30 minutes). These reaction conditions were confirmed by applying them to infectious soil samples collected from the field. The limitation of detection was identified as 10 fg of genomic DNA under optimized LAMP conditions. These LAMP-based ToFP devices were generated with easily available stationery materials and the utility of these devices to analyze the LAMP results were confirmed through several experiments on a total of 14 field samples. The results showed that the developed LAMP-based detection system was very sensitive and had the advantages of rapid detection and high availability in the field.


Asunto(s)
Técnicas de Amplificación de Ácido Nucleico
4.
ACS Nano ; 14(4): 3822-3835, 2020 04 28.
Artículo en Inglés | MEDLINE | ID: mdl-32223179

RESUMEN

COVID-19 has spread globally since its discovery in Hubei province, China in December 2019. A combination of computed tomography imaging, whole genome sequencing, and electron microscopy were initially used to screen and identify SARS-CoV-2, the viral etiology of COVID-19. The aim of this review article is to inform the audience of diagnostic and surveillance technologies for SARS-CoV-2 and their performance characteristics. We describe point-of-care diagnostics that are on the horizon and encourage academics to advance their technologies beyond conception. Developing plug-and-play diagnostics to manage the SARS-CoV-2 outbreak would be useful in preventing future epidemics.


Asunto(s)
Betacoronavirus/patogenicidad , Técnicas de Laboratorio Clínico , Infecciones por Coronavirus/diagnóstico , Neumonía Viral/diagnóstico , Pruebas en el Punto de Atención , Teléfono Inteligente , Humanos , Aplicaciones Móviles , Técnicas de Amplificación de Ácido Nucleico , Pandemias , Vigilancia de la Población , Reacción en Cadena en Tiempo Real de la Polimerasa , Tomografía Computarizada por Rayos X , Proteínas Virales/análisis
6.
Lab Chip ; 20(9): 1621-1627, 2020 05 05.
Artículo en Inglés | MEDLINE | ID: mdl-32334422

RESUMEN

Rapid, sensitive and specific detection and reporting of infectious pathogens is important for patient management and epidemic surveillance. We demonstrated a point-of-care system integrated with a smartphone for detecting live virus from nasal swab media, using a panel of equine respiratory infectious diseases as a model system for corresponding human diseases such as COVID-19. Specific nucleic acid sequences of five pathogens were amplified by loop-mediated isothermal amplification on a microfluidic chip and detected at the end of reactions by the smartphone. Pathogen-spiked horse nasal swab samples were correctly diagnosed using our system, with a limit of detection comparable to that of the traditional lab-based test, polymerase chain reaction, with results achieved in ∼30 minutes.


Asunto(s)
Enfermedades de los Caballos/diagnóstico , Dispositivos Laboratorio en un Chip , Técnicas de Diagnóstico Molecular/métodos , Técnicas de Amplificación de Ácido Nucleico/métodos , Trastornos Respiratorios/veterinaria , Teléfono Inteligente , Animales , Betacoronavirus/aislamiento & purificación , Técnicas de Laboratorio Clínico/métodos , Infecciones por Coronavirus/diagnóstico , Herpesvirus Équido 1/aislamiento & purificación , Herpesvirus Équido 4/aislamiento & purificación , Enfermedades de los Caballos/microbiología , Enfermedades de los Caballos/virología , Caballos , Subtipo H3N8 del Virus de la Influenza A/aislamiento & purificación , Aplicaciones Móviles , Nariz/microbiología , Nariz/virología , Sistemas de Atención de Punto , Trastornos Respiratorios/diagnóstico , Trastornos Respiratorios/microbiología , Trastornos Respiratorios/virología , Streptococcus equi/aislamiento & purificación
7.
Emerg Microbes Infect ; 9(1): 787-793, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32241244

RESUMEN

On 31 December 2019, a severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) emerged in Wuhan, Hubei province, China, and caused the outbreak of the Coronavirus Disease 2019 (COVID-19). To date, computed tomography (CT) findings have been recommended as major evidence for the clinical diagnosis of COVID-19 in Hubei, China. This review focuses on the imaging characteristics and changes throughout the disease course in patients with COVID-19 in order to provide some help for clinicians. Typical CT findings included bilateral ground-glass opacity, pulmonary consolidation, and prominent distribution in the posterior and peripheral parts of the lungs. This review also provides a comparison between COVID-19 and other diseases that have similar CT findings. Since most patients with COVID-19 infection share typical imaging features, radiological examinations have an irreplaceable role in screening, diagnosis and monitoring treatment effects in clinical practice.


Asunto(s)
Infecciones por Coronavirus/diagnóstico por imagen , Pulmón , Neumonía Viral/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Betacoronavirus , Técnicas de Laboratorio Clínico , Infecciones por Coronavirus/diagnóstico , Diagnóstico Diferencial , Progresión de la Enfermedad , Humanos , Pulmón/diagnóstico por imagen , Pulmón/patología , Técnicas de Amplificación de Ácido Nucleico , Pandemias , Radiografía Torácica , Síndrome Respiratorio Agudo Grave/diagnóstico por imagen
8.
BMC Infect Dis ; 20(1): 281, 2020 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-32295538

RESUMEN

BACKGROUND: Severe fever with thrombocytopenia syndrome (SFTS) is an emerging infectious disease that commonly has a lethal course caused by the tick-borne Huaiyangshan banyang virus [former SFTS virus (SFTSV)]. The viral load in various body fluids in SFTS patients and the best infection control measure for SFTS patients have not been fully established. CASE PRESENTATION: A 79-year-old man was bitten by a tick while working in the bamboo grove in Nagasaki Prefecture in the southwest part of Japan. Due to the occurrence of impaired consciousness, he was referred to Nagasaki University Hospital for treatment. The serum sample tested positive for SFTSV-RNA in the genome amplification assay, and he was diagnosed with SFTS. Furthermore, SFTSV-RNA was detected from the tick that had bitten the patient. He was treated with multimodal therapy, including platelet transfusion, antimicrobials, antifungals, steroids, and continuous hemodiafiltration. His respiration was assisted with mechanical ventilation. On day 5, taking the day on which he was hospitalized as day 0, serum SFTSV-RNA levels reached a peak and then decreased. However, the cerebrospinal fluid collected on day 13 was positive for SFTSV-RNA. In addition, although serum SFTSV-RNA levels decreased below the detectable level on day 16, he was diagnosed with pneumonia with computed tomography. SFTSV-RNA was detected in the bronchoalveolar lavage fluid on day 21. By day 31, he recovered consciousness completely. The pneumonia improved by day 51, but SFTSV-RNA in the sputum remained positive for approximately 4 months after disease onset. Strict countermeasures against droplet/contact infection were continuously conducted. CONCLUSIONS: Even when SFTSV genome levels become undetectable in the serum of SFTS patients in the convalescent phase, the virus genome remains in body fluids and tissues. It may be possible that body fluids such as respiratory excretions become a source of infection to others; thus, careful infection control management is needed.


Asunto(s)
Líquidos Corporales/virología , Encefalopatías/virología , Infecciones por Bunyaviridae/epidemiología , Hemorragia Gastrointestinal/virología , Phlebovirus/genética , Neumonía/virología , ARN Viral/sangre , Anciano , Animales , Encefalopatías/tratamiento farmacológico , Líquido del Lavado Bronquioalveolar/virología , Infecciones por Bunyaviridae/tratamiento farmacológico , Infecciones por Bunyaviridae/virología , Terapia Combinada , Hemorragia Gastrointestinal/tratamiento farmacológico , Hospitales Universitarios , Humanos , Japón/epidemiología , Masculino , Técnicas de Amplificación de Ácido Nucleico , Phlebovirus/aislamiento & purificación , Neumonía/tratamiento farmacológico , Esputo/virología , Garrapatas/virología , Resultado del Tratamiento , Carga Viral
11.
Int J Mol Sci ; 21(8)2020 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-32325642

RESUMEN

COVID-19 has become a major global public health burden, currently causing a rapidly growing number of infections and significant morbidity and mortality around the world. Early detection with fast and sensitive assays and timely intervention are crucial for interrupting the spread of the COVID-19 virus (SARS-CoV-2). Using a mismatch-tolerant amplification technique, we developed a simple, rapid, sensitive and visual reverse transcription loop-mediated isothermal amplification (RT-LAMP) assay for SARS-CoV-2 detection based on its N gene. The assay has a high specificity and sensitivity, and robust reproducibility, and its results can be monitored using a real-time PCR machine or visualized via colorimetric change from red to yellow. The limit of detection (LOD) of the assay is 118.6 copies of SARS-CoV-2 RNA per 25 µL reaction. The reaction can be completed within 30 min for real-time fluorescence monitoring, or 40 min for visual detection when the template input is more than 200 copies per 25 µL reaction. To evaluate the viability of the assay, a comparison between the RT-LAMP and a commercial RT-qPCR assay was made using 56 clinical samples. The SARS-CoV-2 RT-LAMP assay showed perfect agreement in detection with the RT-qPCR assay. The newly-developed SARS-CoV-2 RT-LAMP assay is a simple and rapid method for COVID-19 surveillance.


Asunto(s)
Betacoronavirus/aislamiento & purificación , Técnicas de Laboratorio Clínico/métodos , Infecciones por Coronavirus , Pandemias , Neumonía Viral , Betacoronavirus/genética , Bioensayo , Infecciones por Coronavirus/diagnóstico , Infecciones por Coronavirus/virología , Humanos , Técnicas de Amplificación de Ácido Nucleico , Neumonía Viral/diagnóstico , Neumonía Viral/virología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Transcripción Reversa , Sensibilidad y Especificidad
12.
Emerg Microbes Infect ; 9(1): 998-1007, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32306853

RESUMEN

The previous outbreaks of SARS-CoV and MERS-CoV have led researchers to study the role of diagnostics in impediment of further spread and transmission. With the recent emergence of the novel SARS-CoV-2, the availability of rapid, sensitive, and reliable diagnostic methods is essential for disease control. Hence, we have developed a reverse transcription loop-mediated isothermal amplification (RT-LAMP) assay for the specific detection of SARS-CoV-2. The primer sets for RT-LAMP assay were designed to target the nucleocapsid gene of the viral RNA, and displayed a detection limit of 102 RNA copies close to that of qRT-PCR. Notably, the assay has exhibited a rapid detection span of 30 min combined with the colorimetric visualization. This test can detect specifically viral RNAs of the SARS-CoV-2 with no cross-reactivity to related coronaviruses, such as HCoV-229E, HCoV-NL63, HCoV-OC43, and MERS-CoV as well as human infectious influenza viruses (type B, H1N1pdm, H3N2, H5N1, H5N6, H5N8, and H7N9), and other respiratory disease-causing viruses (RSVA, RSVB, ADV, PIV, MPV, and HRV). Furthermore, the developed RT-LAMP assay has been evaluated using specimens collected from COVID-19 patients that exhibited high agreement to the qRT-PCR. Our RT-LAMP assay is simple to perform, less expensive, time-efficient, and can be used in clinical laboratories for preliminary detection of SARS-CoV-2 in suspected patients. In addition to the high sensitivity and specificity, this isothermal amplification conjugated with a single-tube colorimetric detection method may contribute to the public health responses and disease control, especially in the areas with limited laboratory capacities.


Asunto(s)
Infecciones por Coronavirus/diagnóstico , Técnicas de Amplificación de Ácido Nucleico/métodos , Neumonía Viral/diagnóstico , Betacoronavirus/genética , Betacoronavirus/aislamiento & purificación , Infecciones por Coronavirus/virología , Humanos , Límite de Detección , Técnicas de Amplificación de Ácido Nucleico/economía , Técnicas de Amplificación de Ácido Nucleico/normas , Proteínas de la Nucleocápside/genética , Pandemias , Neumonía Viral/virología , Factores de Tiempo
13.
PLoS Negl Trop Dis ; 14(3): e0008129, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-32203507

RESUMEN

BACKGROUND: Schistosomiasis is a neglected tropical parasitic disease associated with severe pathology, mortality and economic loss worldwide. Programs for disease control may benefit from specific and sensitive diagnostic methods to detect Schistosoma trematodes in aquatic environments. Here we report the development of novel environmental DNA (eDNA) qPCR assays for the presence of the human-infecting species Schistosoma mansoni, S. haematobium and S. japonicum. METHODOLOGY/PRINCIPAL FINDINGS: We first tested the specificity of the assays across the three species using genomic DNA preparations which showed successful amplification of target sequences with no cross amplification between the three focal species. In addition, we evaluated the specificity of the assays using synthetic DNA of multiple Schistosoma species, and demonstrated a high overall specificity; however, S. japonicum and S. haematobium assays showed cross-species amplification with very closely-related species. We next tested the effectiveness of the S. mansoni assay using eDNA samples from aquaria containing infected host gastropods, with the target species revealed as present in all infected aquaria. Finally, we evaluated the effectiveness of the S. mansoni and S. haematobium assays using eDNA samples from eight discrete natural freshwater sites in Tanzania, and demonstrated strong correspondence between infection status established using eDNA and conventional assays of parasite prevalence in host snails. CONCLUSIONS/SIGNIFICANCE: Collectively, our results suggest that eDNA monitoring is able to detect schistosomes in freshwater bodies, but refinement of the field sampling, storage and assay methods are likely to optimise its performance. We anticipate that environmental DNA-based approaches will help to inform epidemiological studies and contribute to efforts to control and eliminate schistosomiasis in endemic areas.


Asunto(s)
ADN Ambiental/aislamiento & purificación , Agua Dulce/parasitología , Schistosoma/clasificación , Schistosoma/genética , Schistosoma/aislamiento & purificación , Animales , ADN de Helmintos/aislamiento & purificación , Monitoreo del Ambiente , Genes de Helminto/genética , Técnicas de Amplificación de Ácido Nucleico/veterinaria , Filogenia , Reacción en Cadena en Tiempo Real de la Polimerasa/veterinaria , Schistosoma haematobium/genética , Schistosoma haematobium/aislamiento & purificación , Schistosoma japonicum/genética , Schistosoma japonicum/aislamiento & purificación , Schistosoma mansoni/genética , Schistosoma mansoni/aislamiento & purificación , Esquistosomiasis/epidemiología , Esquistosomiasis/parasitología , Esquistosomiasis mansoni/epidemiología , Esquistosomiasis mansoni/parasitología , Caracoles/parasitología , Especificidad de la Especie , Tanzanía
14.
PLoS Negl Trop Dis ; 14(3): e0008130, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-32130209

RESUMEN

BACKGROUND: Yellow fever, dengue, chikungunya and Zika viruses are responsible for considerable morbidity and mortality in humans. Aedes aegypti and Aedes albopictus are the most important mosquito vectors involved in their transmission. Accurate identification of these species is essential for the implementation of control programs to limit arbovirus transmission, during suspected detections at ports of first entry, to delimit incursions or during presence/absence surveillance programs in regions vulnerable to invasion. We developed and evaluated simple and rapid colorimetric isothermal tests to detect these two mosquito species based on loop-mediated isothermal amplification (LAMP) targeting the ribosomal RNA internal transcribed spacer 1 (ITS1). METHODOLOGY/PRINCIPAL FINDINGS: Samples were prepared by homogenizing and heating at 99 oC for 10 min before an aliquot was added to the LAMP reaction. After 40 min incubation at 65 oC, a colour change indicated a positive result. The tests were 100% sensitive and species-specific, and demonstrated a limit of detection comparable with PCR-based detection (TaqMan chemistry). The LAMP assays were able to detect target species for various life stages tested (adult, 1st instar larva, 4th instar larva and pupa), and body components, such as legs, wings and pupal exuviae. Importantly, the LAMP assays could detect Ae. aegypti DNA in mosquitoes stored in Biogents Sentinel traps deployed in the field for 14 d. A single 1st instar Ae. aegypti larva could also be detected in a pool of 1,000 non-target 1st instar Aedes notoscriptus, thus expediting processing of ovitrap collections obtained during presence/absence surveys. A simple syringe-sponge protocol facilitated the concentration and collection of larvae from the ovitrap water post-hatch. CONCLUSIONS/SIGNIFICANCE: We describe the development of LAMP assays for species identification and demonstrate their direct application for surveillance in different field contexts. The LAMP assays described herein are useful adjuncts to laboratory diagnostic testing or could be employed as standalone tests. Their speed, ease-of-use, low cost and need for minimal equipment and training make the LAMP assays ideal for adoption in low-resource settings without the need to access diagnostic laboratory services.


Asunto(s)
Aedes/clasificación , Aedes/crecimiento & desarrollo , Colorimetría/métodos , Entomología/métodos , Técnicas de Diagnóstico Molecular/métodos , Mosquitos Vectores/clasificación , Mosquitos Vectores/crecimiento & desarrollo , Técnicas de Amplificación de Ácido Nucleico/métodos , Aedes/genética , Animales , ADN Espaciador Ribosómico/genética , Femenino , Mosquitos Vectores/genética , Sensibilidad y Especificidad
15.
Balkan Med J ; 37(3): 163-165, 2020 04 10.
Artículo en Inglés | MEDLINE | ID: mdl-32157862

RESUMEN

Background: Since December 2019, the outbreak of the novel coronavirus has impacted nearly >90,000 people in more than 75 countries. In this case report, we aim to define the chest computed tomography findings of 2019-novel coronavirus associated with pneumonia and its successful resolution after treatment. Case Report: A fifty-year-old female patient, who is a businesswoman, presented with chief complaints of "fever for one week, diarrhea, anorexia, and asthenia." Initially, she was given Tamiflu. The influenza A virus serology was negative. Three days later, levofloxacin was started because the patient's symptoms did not improve. The novel coronavirus nucleic acid test was negative. It was noted that before the onset of the disease, the patient went to Wuhan on a business trip. Despite the given treatment, her body temperature rose to 39.2°C and she was referred to our clinic for further evaluation. Then, chest computed tomography was performed and showed bilateral multifocal ground glass opacities with consolidation which suggested viral pneumonia as a differential diagnosis, and the subsequent 2019-novel coronavirus pneumonia nucleic acid test was positive. Conclusion: Chest computed tomography offers fast and convenient evaluation of patients with suspected 2019-novel coronavirus pneumonia.


Asunto(s)
Betacoronavirus , Infecciones por Coronavirus , Pandemias , Neumonía Viral , Tomografía Computarizada por Rayos X , Betacoronavirus/genética , Betacoronavirus/aislamiento & purificación , Técnicas de Laboratorio Clínico , Infecciones por Coronavirus/complicaciones , Infecciones por Coronavirus/diagnóstico , Infecciones por Coronavirus/diagnóstico por imagen , Femenino , Fiebre/etiología , Humanos , Pulmón/diagnóstico por imagen , Pulmón/patología , Persona de Mediana Edad , Técnicas de Amplificación de Ácido Nucleico , Neumonía Viral/complicaciones , Neumonía Viral/diagnóstico por imagen
16.
Int J Infect Dis ; 93: 264-267, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32114193

RESUMEN

An ongoing outbreak of severe respiratory pneumonia associated with the 2019 novel coronavirus has recently emerged in China. Here we report the epidemiological, clinical, laboratory and radiological characteristics of 19 suspect cases. We compared the positive ratio of 2019-nCoV nucleic acid amplification test results from different samples including oropharyngeal swab, blood, urine and stool with 3 different fluorescent RT-PCR kits. Nine out of the 19 patients had 2019-nCoV infection detected using oropharyngeal swab samples, and the virus nucleic acid was also detected in eight of these nine patients using stool samples. None of positive results was identified in the blood and urine samples. These three different kits got the same result for each sample and the positive ratio of nucleic acid detection for 2019-nCoV was only 47.4% in the suspect patients. Therefore, it is possible that infected patients have been missed by using nucleic acid detection only. It might be better to make a diagnosis combining the computed tomography scans and nucleic acid detection.


Asunto(s)
Betacoronavirus/genética , Infecciones por Coronavirus/diagnóstico , Técnicas de Amplificación de Ácido Nucleico , Neumonía Viral/diagnóstico , Sangre/virología , China/epidemiología , Infecciones por Coronavirus/virología , Heces/virología , Femenino , Humanos , Técnicas de Amplificación de Ácido Nucleico/normas , Pandemias , Faringe/virología , Neumonía Viral/virología , Orina/virología , Adulto Joven
17.
Zhejiang Da Xue Xue Bao Yi Xue Ban ; 49(1): 0, 2020 May 25.
Artículo en Chino | MEDLINE | ID: mdl-32222121

RESUMEN

OBJECTIVE: To explore the feasibility of surgical treatment for cancer patients complicated with corona virus disease 2019 (COVID-19). METHODS: The management and clinical outcome of a sigmoid cancer patient with COVID-19 were analyzed. RESULTS: The inflammation indicators and fever of this patient were effectively controlled and the lung lesions remained stable after active anti-viral treatment, then the radical colorectomy was performed after the viral negative conversion for twice. CONCLUSIONS: The case indicates that it may feasible to undergo radical tumor surgery for cancer patients with COVID-19 after the virus nucleic acid testing turns negative and more studies are needed to confirm this conclusion.


Asunto(s)
Neoplasias del Colon/cirugía , Infecciones por Coronavirus , Pandemias , Neumonía Viral , Antivirales/uso terapéutico , Betacoronavirus , Técnicas de Laboratorio Clínico , Neoplasias del Colon/complicaciones , Neoplasias del Colon/virología , Infecciones por Coronavirus/complicaciones , Infecciones por Coronavirus/diagnóstico , Infecciones por Coronavirus/tratamiento farmacológico , Fiebre , Humanos , Técnicas de Amplificación de Ácido Nucleico , Neumonía Viral/complicaciones , Neumonía Viral/diagnóstico , Neumonía Viral/tratamiento farmacológico
18.
Artículo en Chino | MEDLINE | ID: mdl-32185923

RESUMEN

OBJECTIVE: To quantitatively evaluate the diagnostic value of variable-temperature and isothermal nucleic acid amplification techniques in the detection of schistosomiasis japonica using a meta-analysis. METHODS: The publications pertaining to the nucleic acid detection of schistosomiasis japonica were searched in electronic databases, including Chinese National Knowledge Infrastructure (CNKI), Wanfang Data, PubMed and ScienceDirect, and the compilations and proceedings of schistosomiasis were manually searched. In addition, the citations of publications associated with the nucleic acid detection of schistosomiasis japonica were traced using a document tracing method. The retrieved literatures were screened according to the inclusion and exclusion criteria, and data were extracted from the included literatures. The quality of the included literatures was assessed using the software RevMan version 5.3, and a meta-analysis was performed using the software MetaDiSc version 1.4. RESULTS: A total of 19 publications covering 24 groups of studies were enrolled, including 5 Chinese publications and 14 English publications. There were 17 groups of studies reporting the comparison between the variable-temperature nucleic acid amplification technique and the golden standard, and 7 groups of studies showing the comparison between the isothermal nucleic acid amplification technique and the golden standard. Assessment of the literature quality indicated a minor overall bias of the included literatures, and the Deek funnel plot showed a possible publication bias in the documents reports variable-temperature nucleic acid amplification techniques. There was a heterogeneity caused by non-threshold effect among the studies associated with the variable-temperature amplification technique, and the random effects model was therefore used to combine the effects. The pooled sensitivity and specificity of the variable-temperature amplification technique were 0.81 (0.79 to 0.83) and 0.73 (0.71 to 0.74) for the diagnosis of schistosomiasis japonica, and area under the SROC curve was 0.944 3. There was no heterogeneity among the studies associated with the isothermal amplification technique, and the fixed effects model was therefore used to combine the effects. The pooled sensitivity and specificity of the isothermal amplification technique were 0.96 (0.94 to 0.98) and 0.95 (0.94 to 0.97) for the diagnosis of schistosomiasis japonica, and area under the SROC curve was 0.989 9. CONCLUSIONS: Both variable-temperature and isothermal nucleic acid amplification techniques have a high efficiency for the diagnosis of schistosomiasis japonica, and the isothermal amplification technique shows a relatively higher accuracy than the variable-temperature amplification technique.


Asunto(s)
Técnicas de Amplificación de Ácido Nucleico , Esquistosomiasis Japónica , Humanos , Curva ROC , Esquistosomiasis Japónica/diagnóstico , Sensibilidad y Especificidad
19.
Monaldi Arch Chest Dis ; 90(1)2020 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-32124585

RESUMEN

Presumptive pulmonary tuberculosis (PTB) patients whose sputum are detected to be smear negative for acid fast bacilli (AFB) present a significant challenge for a treating physician. Initiating these patients on anti tuberculous treatment (ATT) on empirical basis is not a good strategy as many were found to be sputum culture for tuberculosis negative on further evaluation according to many previous studies. In India due to resource limited settings and lack of knowledge about newest diagnostic modalities patients are often initiated only on the basis of characteristic clinical symptoms and chest radiographic abnormalities. This study was conducted to identify the advantage of application of sputum cartridge based nucleic acid amplification test (CBNAAT) in sputum AFB smear negative presumptive pulmonary TB patients. Our study concluded that clinical symptoms and radiological characteristics cannot differentiate TB patients from non-TB patients. Treating patients only on empirical basis would have resulted in unnecessary treatment of 41 patients.


Asunto(s)
Técnicas de Amplificación de Ácido Nucleico , Tuberculosis Pulmonar/diagnóstico , Humanos , India , Sensibilidad y Especificidad , Esputo
20.
Biochemistry (Mosc) ; 85(2): 147-166, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32093592

RESUMEN

Recently, there has been a rapid progress in the development of techniques for isothermal amplification of nucleic acids as an alternative to polymerase chain reaction (PCR). The advantage of these methods is that the nucleic acids amplification can be carried out at constant temperature, unlike PCR, which requires cyclic temperature changes. Moreover, isothermal amplification can be conducted directly in living cells. This review describes the principles of isothermal amplification techniques and demonstrates their high efficiency in designing new highly sensitive detection methods of nucleic acids and enzymes involved in their modifications. The data on successful application of isothermal amplification methods for the analysis of cells and biomolecules with the use of DNA/RNA aptamers are presented.


Asunto(s)
ADN/análisis , ADN/genética , Técnicas de Amplificación de Ácido Nucleico/métodos , ARN/análisis , ARN/genética , Temperatura , Animales , ADN/metabolismo , Humanos , Reacción en Cadena de la Polimerasa , ARN/metabolismo
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA