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2.
Microbes Infect ; 22(2): 74-79, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-32017984

RESUMEN

On 10 January 2020, a new coronavirus causing a pneumonia outbreak in Wuhan City in central China was denoted as 2019-nCoV by the World Health Organization (WHO). As of 24 January 2020, there were 887 confirmed cases of 2019-nCoV infection, including 26 deaths, reported in China and other countries. Therefore, combating this new virus and stopping the epidemic is a matter of urgency. Here, we focus on advances in research and development of fast diagnosis methods, as well as potential prophylactics and therapeutics to prevent or treat 2019-nCoV infection.


Asunto(s)
Betacoronavirus/patogenicidad , Infecciones por Coronavirus/diagnóstico , Infecciones por Coronavirus/terapia , Neumonía Viral/diagnóstico , Neumonía Viral/terapia , Secuencia de Aminoácidos , Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/inmunología , Antivirales/uso terapéutico , Betacoronavirus/aislamiento & purificación , China/epidemiología , Humanos , Técnicas de Amplificación de Ácido Nucleico , ARN Viral/análisis , Alineación de Secuencia , Glicoproteína de la Espiga del Coronavirus/inmunología , Vacunas Virales/inmunología , Vacunas Virales/uso terapéutico
3.
Euro Surveill ; 25(3)2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31992387

RESUMEN

BACKGROUND: The ongoing outbreak of the recently emerged novel coronavirus (2019-nCoV) poses a challenge for public health laboratories as virus isolates are unavailable while there is growing evidence that the outbreak is more widespread than initially thought, and international spread through travellers does already occur. AIM: We aimed to develop and deploy robust diagnostic methodology for use in public health laboratory settings without having virus material available. METHODS: Here we present a validated diagnostic workflow for 2019-nCoV, its design relying on close genetic relatedness of 2019-nCoV with SARS coronavirus, making use of synthetic nucleic acid technology. RESULTS: The workflow reliably detects 2019-nCoV, and further discriminates 2019-nCoV from SARS-CoV. Through coordination between academic and public laboratories, we confirmed assay exclusivity based on 297 original clinical specimens containing a full spectrum of human respiratory viruses. Control material is made available through European Virus Archive - Global (EVAg), a European Union infrastructure project. CONCLUSION: The present study demonstrates the enormous response capacity achieved through coordination of academic and public laboratories in national and European research networks.


Asunto(s)
Infecciones por Coronavirus/diagnóstico , Infecciones por Coronavirus/virología , Coronavirus/clasificación , Coronavirus/genética , Técnicas de Laboratorio Clínico/métodos , Coronavirus/aislamiento & purificación , Brotes de Enfermedades , Humanos , ARN Viral/análisis , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Sensibilidad y Especificidad
4.
Viruses ; 12(1)2020 01 09.
Artículo en Inglés | MEDLINE | ID: mdl-31936476

RESUMEN

Porcine deltacoronavirus (PDCoV) is a porcine enteropathogenic coronavirus that causes watery diarrhea, vomiting, and frequently death in piglets, causing serious economic losses to the pig industry. The strain CHN-JS-2017 was isolated and identified by cytopathology, immunofluorescence assays, transmission electron microscopy, and sequence analysis. A nucleotide sequence alignment showed that the whole genome of CHN-JS-2017 is 97.4%-99.6% identical to other PDCoV strains. The pathogenicity of the CHN-JS-2017 strain was investigated in orally inoculated five-day-old piglets; the piglets developed acute, watery diarrhea, but all recovered and survived. CHN-JS-2017 infection-induced microscopic lesions were observed, and viral antigens were detected mainly by immunohistochemical staining in the small intestine. The neonatal Fc receptor (FcRn) and polymeric immunoglobulin receptor (pIgR) are crucial immunoglobulin (Ig) receptors for the transcytosis ofimmunoglobulin G (IgG), IgA, or IgM. Importantly, CHN-JS-2017 infected five-day-old piglets could significantly down-regulate the expression of FcRn, pIgR, and nuclear factor-kappa B (NF-κB)in the intestinal mucosa. Note that the level of FcRn mRNA in the intestinal mucosa of normal piglets is positively correlated with pIgR and NF-κB. At the same time, the expressions of FcRn, pIgR, and NF-κB mRNA are also positively correlated in infected piglets. These results may help explain the immunological and pathological changes associated with porcine deltacorononirus infection.


Asunto(s)
Infecciones por Coronavirus/veterinaria , Coronavirus/clasificación , Antígenos de Histocompatibilidad Clase I/inmunología , Mucosa Intestinal/inmunología , Receptores Fc/inmunología , Receptores de Inmunoglobulina Polimérica/inmunología , Enfermedades de los Porcinos/virología , Animales , Antígenos Virales/análisis , Coronavirus/aislamiento & purificación , Infecciones por Coronavirus/inmunología , Diarrea/veterinaria , Diarrea/virología , Regulación de la Expresión Génica , Mucosa Intestinal/virología , Intestino Delgado/inmunología , Intestino Delgado/virología , FN-kappa B/inmunología , Filogenia , ARN Viral/análisis , Alineación de Secuencia , Análisis de Secuencia de ADN , Porcinos , Enfermedades de los Porcinos/inmunología , Esparcimiento de Virus
5.
Viruses ; 12(2)2020 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-31991673

RESUMEN

Hepatitis E virus (HEV) is a major concern in public health worldwide. Infections with HEV genotypes 3, 4, or 7 can lead to chronic hepatitis while genotype 1 infections can trigger severe hepatitis in pregnant women. Infections with all genotypes can worsen chronic liver diseases. As virions are lipid-associated in blood and naked in feces, efficient methods of propagating HEV clinical strains in vitro and evaluating the infectivity of both HEV forms are needed. We evaluated the spread of clinical strains of HEV genotypes 1 (HEV1) and 3 (HEV3) by quantifying viral RNA in culture supernatants and cell lysates. Infectivity was determined by endpoint dilution and calculation of the tissue culture infectious dose 50 (TCID50). An enhanced HEV production could be obtained varying the composition of the medium, including fetal bovine serum (FBS) and dimethylsulfoxide (DMSO) content. This increased TCID50 from 10 to 100-fold and allowed us to quantify HEV1 infectivity. These optimized methods for propagating and measuring HEV infectivity could be applied to health safety processes and will be useful for testing new antiviral drugs.


Asunto(s)
Virus de la Hepatitis E/crecimiento & desarrollo , Cultivo de Virus/métodos , Medios de Cultivo , Genotipo , Células Hep G2 , Virus de la Hepatitis E/genética , Humanos , ARN Viral/análisis
6.
Viruses ; 12(2)2020 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-31991915

RESUMEN

Ticks transmit a wide variety of pathogens including bacteria, parasites and viruses. Over the last decade, numerous novel viruses have been described in arthropods, including ticks, and their characterization has provided new insights into RNA virus diversity and evolution. However, little is known about their ability to infect vertebrates. As very few studies have described the diversity of viruses present in ticks from the Caribbean, we implemented an RNA-sequencing approach on Amblyomma variegatum and Rhipicephalus microplus ticks collected from cattle in Guadeloupe and Martinique. Among the viral communities infecting Caribbean ticks, we selected four viruses belonging to the Chuviridae, Phenuiviridae and Flaviviridae families for further characterization and designing antibody screening tests. While viral prevalence in individual tick samples revealed high infection rates, suggesting a high level of exposure of Caribbean cattle to these viruses, no seropositive animals were detected. These results suggest that the Chuviridae- and Phenuiviridae-related viruses identified in the present study are more likely tick endosymbionts, raising the question of the epidemiological significance of their occurrence in ticks, especially regarding their possible impact on tick biology and vector capacity. The characterization of these viruses might open the door to new ways of preventing and controlling tick-borne diseases.


Asunto(s)
Enfermedades de los Bovinos , Flaviviridae/aislamiento & purificación , Ixodidae/virología , Virus ARN/clasificación , Virus ARN/aislamiento & purificación , Rhipicephalus/virología , Infestaciones por Garrapatas/veterinaria , Animales , Anticuerpos Antivirales/sangre , Bovinos/inmunología , Enfermedades de los Bovinos/inmunología , Enfermedades de los Bovinos/parasitología , Susceptibilidad a Enfermedades , Flaviviridae/genética , Flaviviridae/inmunología , Genoma Viral , Martinica , Filogenia , Virus ARN/genética , Virus ARN/inmunología , ARN Viral/análisis , ARN Viral/genética , Estudios Seroepidemiológicos , Infestaciones por Garrapatas/inmunología , Indias Occidentales
7.
Euro Surveill ; 25(3)2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31992389

RESUMEN

Recognition of measles is crucial to prevent transmissions in the hospital settings. Little is known about the level of recognition of measles and possible causes of not recognising the disease by physicians in the post-vaccine era. We report on a measles outbreak in a paediatric hospital in Austria in January to February 2017 with strikingly high numbers of not recognised cases. The extent and course of the outbreak were assessed via retrospective case finding. Thirteen confirmed measles cases were identified, two with atypical clinical picture. Of eight cases with no known epidemiological link, only one was diagnosed immediately; four were recognised with delay and three only retrospectively. Eleven typical measles cases had four 'unrecognised visits' to the outpatient clinic and 28 on the ward. Two atypical cases had two 'unrecognised visits' to the outpatient clinic and 19 on the ward.Thirteen clinicians did not recognise typical measles (atypical cases not included). Twelve of 23 physicians involved had never encountered a patient with measles before. The direct and indirect costs related to the outbreak were calculated to be over EUR 80,000. Our findings suggest the need to establish regular training programmes about measles, including diagnostic pitfalls in paediatric hospitals.


Asunto(s)
Brotes de Enfermedades/estadística & datos numéricos , Virus del Sarampión/genética , Virus del Sarampión/inmunología , Sarampión/epidemiología , Adolescente , Adulto , Austria/epidemiología , Niño , Preescolar , Ensayo de Inmunoadsorción Enzimática , Femenino , Hospitales Pediátricos , Hospitales Universitarios , Humanos , Inmunoglobulina G/sangre , Inmunoglobulina M/sangre , Lactante , Masculino , Virus del Sarampión/aislamiento & purificación , ARN Viral/análisis , Estudios Retrospectivos , Factores de Riesgo , Adulto Joven
8.
Ann Hematol ; 99(2): 381-383, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31768673
9.
Int J Food Microbiol ; 317: 108479, 2020 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-31874303

RESUMEN

Hepatitis E virus (HEV) infection is endemic in many developing countries and becomes of interest in the developed countries. Several animals are sources of HEV infection to humans. Recently, HEV was detected in the milk of cows in China, this data comes up with the probability of HEV transmission to humans via ingestion of contaminated milk. In Egypt, contaminated water and residing in rural communities are risk factors for HEV infection, while limited data is available on the zoonotic HEV transmission. Since pigs, wild boars, camels are not common in Egypt, we investigated if cows and/or cow milk represent a risk factor for HEV transmission in the Assiut governorate. Milk samples (n = 480), collected from Assiut city and 12 non-mixed dairy farms distributed in the rural communities, were tested for HEV markers such as anti-HEV IgG, HEV RNA, and HEV Ag. All milk samples collected from Assiut city (n = 220) were negative for HEV markers. Also, milk samples collected from 11 farms (n = 220) were negative for HEV markers. While, in one farm, we could detect anti-HEV IgG in 8 out of 40 samples (20%), HEV RNA and HEV Ag were detectable in 1 out of 40 samples (2.5%). However, we could not detect the HEV markers in the stool from anti-HEV IgG positive cows. Surprisingly, phylogenetic analysis of the isolated virus revealed it belonged to HEV-3 subtype 3a. Importantly, when cows from the positive farm were retested 1 month later, we observed an increase in the number of animals that were positive for anti-HEV IgG (10/40, 25%). In addition, the level of anti-HEV IgG was significantly higher in the milk of these cows in the second collection than the samples of the first collection suggesting ongoing infection on this farm. In conclusion: we reported that HEV-3 and/or HEV like agent was detected in the milk of the cow distributed in rural communities of Assiut governates. Investigation of the cow milk should be done to assess if the cow milk is a risk factor for HEV transmission for Egyptian people, especially in rural communities.


Asunto(s)
Virus de la Hepatitis E/aislamiento & purificación , Hepatitis E , Leche/virología , Animales , Bovinos , Enfermedades de los Bovinos/epidemiología , Enfermedades de los Bovinos/virología , China/epidemiología , Egipto , Granjas , Heces/virología , Femenino , Hepatitis E/epidemiología , Hepatitis E/transmisión , Hepatitis E/veterinaria , Virus de la Hepatitis E/genética , Humanos , Filogenia , Prevalencia , ARN Viral/análisis , ARN Viral/genética , Porcinos , Enfermedades de los Porcinos/epidemiología , Enfermedades de los Porcinos/virología
10.
Talanta ; 206: 120201, 2020 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-31514868

RESUMEN

Human immunodeficiency virus (HIV) is a lentivirus that leads to acquired immunodeficiency syndrome (AIDS). With increasing awareness of AIDS emerging as a global public health threat, different HIV testing kits have been developed to detect antibodies (Ab) directed toward different parts of HIV. A great limitation of these tests is that they can not detect HIV antibodies during early virus infection. Therefore, to overcome this challenge, a wide range of biosensors have been developed for early diagnosis of HIV infection. A significant amount of these studies have been focused on the application of nanomaterials for improving the sensitivity and accuracy of the sensing methods. Following an introduction into this field, a first section of this review covers the synthesis and applicability of such nanomaterials as metal nanoparticles (NPs), quantum dots (QDs), carbon-based nanomaterials and metal nanoclusters (NCs). A second larger section covers the latest developments concerning nanomaterial-based biosensors for HIV diagnosis, with paying a special attention to the determination of CD4+ cells as a hall mark of HIV infection, HIV gene, HIV p24 core protein, HIV p17 peptide, HIV-1 virus-like particles (VLPs) and HIV related enzymes, particularly those that are passed on from the virus to the CD4+ T lymphocytes and are necessary for viral reproduction within the host cell. These studies are described in detail along with their diverse principles/mechanisms (e.g. electrochemistry, fluorescence, electromagnetic-piezoelectric, surface plasmon resonance (SPR), surface enhanced Raman spectroscopy (SERS) and colorimetry). Despite the significant progress in HIV biosensing in the last years, there is a great need for the development of point-of-care (POC) technologies which are affordable, robust, easy to use, portable, and possessing sufficient quantitative accuracy to enable clinical decision making. In the final section, the focus is on the portable sensing devices as a new standard of POC and personalized diagnostics.


Asunto(s)
Técnicas Biosensibles/métodos , Infecciones por VIH/diagnóstico , VIH , Nanoestructuras/química , Anticuerpos Antivirales/análisis , Anticuerpos Antivirales/inmunología , Biomarcadores/análisis , ADN Viral/análisis , Diagnóstico Precoz , VIH/química , VIH/genética , VIH/inmunología , Humanos , Pruebas en el Punto de Atención , ARN Viral/análisis , Proteínas Virales/análisis
12.
Pan Afr Med J ; 34: 76, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31819792

RESUMEN

Introduction: The diagnosis of Lassa fever is crucial to confirm cases, as well as to control/prevent nosocomial and community-based transmission and initiation of treatment, which is still limited in the country. Thus, we aimed at providing some information on the laboratory detection of Lassa from suspected cases in Nigeria. Methods: This was a retrospective study of seasonal Lassa fever outbreaks data from 1,263 samples analyzed using Reverse Transcription-Polymerase Chain Reaction (RT-PCR) at the Virology Research Laboratory, College of Medicine, University of Lagos/Lagos University Teaching Hospital between year 2011 and 2017. Data were analyzed using the 21st edition of SPSS statistical software (2015). Results: The RT-PCR test confirmed the presence of Lassa in 112 (8.9%) comprising 61 (54.4%) males, 48 (42.9%) females and 3 (2.7%) individuals without gender information. Those aged between 18 and 49 years were mostly affected. There was a decline in the detection of Lassa from 4.7% in 2011/2012 to less than 1% by the 2014/2015. However, during the 2015/2016 and 2016/2017 seasons the detection rates increased to 10.4% and 15.1% respectively. The Northern region of Nigeria reported high confirmed cases of Lassa. The South Western region also witnessed an increased Lassa fever positivity rate of 13.4% of which Lagos and Ogun states being the focal state of Lassa activity in the region. Conclusion: These established the need for heightening the continued surveillance for Lassa as well as the establishment of other testing facilities within these endemic regions for prompt diagnosis of Lassa fever.


Asunto(s)
Brotes de Enfermedades , Fiebre de Lassa/epidemiología , Virus Lassa/aislamiento & purificación , ARN Viral/análisis , Adolescente , Adulto , Anciano , Niño , Preescolar , Estudios Transversales , Femenino , Humanos , Lactante , Masculino , Persona de Mediana Edad , Nigeria/epidemiología , Estudios Retrospectivos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Adulto Joven
14.
BMC Infect Dis ; 19(1): 955, 2019 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-31706284

RESUMEN

BACKGROUND: Identification and knowledge of settings with high prevalence of hepatitis C virus (HCV) infection is important when aiming for elimination of HCV. The primary aim of this study was to estimate the prevalence of viremic HCV infection among Swedish prisoners. Secondary aims were to estimate the prevalence of hepatitis B surface antigen (HBsAg), human immunodeficiency virus (HIV), and the proportion who have received hepatitis B virus (HBV) vaccination. METHODS: A cross-sectional study of all incarcerated persons (n = 667) at all prisons (n = 9) in Stockholm County was conducted. All prisoners are routinely offered opt-in screening for HCV antibodies (anti-HCV), HCV RNA, HBsAg, anti-HBs, anti-HBc and HIV Ag/Ab at prison in Sweden. Data on the results of these tests and the number of received HBV vaccine doses were collected from the prison medical records. The parameters of HCV RNA, anti-HCV, and occurrence of testing for HCV were analysed in multiple logistic regression models in relation to age, sex and prison security class. RESULTS: The median age was 35 (IQR 26-44) years, and 93.4% were men. Seventy-one percent (n = 471) had been tested for anti-HCV, 70% (n = 465) for HBsAg and 71% (n = 471) for HIV. The prevalence of anti-HCV, HCV RNA, HBsAg and HIV Ag/Ab was 17.0, 11.5, 1.9, and 0.2%, respectively among tested persons. The proportion of prisoners who had received full HBV vaccination was 40.6% (n = 271) among all study subjects. CONCLUSIONS: The prevalence of viremic HCV infection among Swedish prisoners in Stockholm County was 11.5%, which is high in comparison to the general population. Therefore, when aiming for the WHO goal of HCV elimination, prisons could suit as a platform for identification and treatment of HCV infection. There is a need to increase testing for blood-borne viruses and to improve vaccination coverage against HBV in Swedish prisons.


Asunto(s)
Infecciones por VIH/epidemiología , Hepatitis B/epidemiología , Hepatitis C/epidemiología , Vacunación/estadística & datos numéricos , Adulto , Estudios Transversales , Femenino , Infecciones por VIH/inmunología , Hepatitis B/inmunología , Antígenos de Superficie de la Hepatitis B/sangre , Hepatitis C/inmunología , Anticuerpos contra la Hepatitis C/sangre , Humanos , Modelos Logísticos , Masculino , Prevalencia , Prisioneros , ARN Viral/análisis , Suecia/epidemiología
15.
Braz J Med Biol Res ; 52(11): e8339, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31721902

RESUMEN

A progressive increase in the circulation of arboviruses in tropical countries has been observed, accounting for 700,000 yearly deaths in the world. The main objective of this article was to identify the presence of Zika (ZIKV), dengue (DENV), and Chikungunya (CHIKV) viruses in immature stages of Aedes aegypti and Ae. albopictus. Household collections of immature phases of the vectors were carried out in the years 2015 and 2016. A total of 2902 dwellings were visited and the rate of infestation with larvae and pupae of Aedes mosquitoes was 283/1462 (19.4%) in March 2015 and 55/1440 (3.8%) in June 2015. In March 2015, 907 larvae/pupae were collected (583 or 64.3% of Ae. aegypti and 324 or 35.7% of Ae. albopictus) while in June 2015 there was a reduction in the number of immature forms found: 197 larvae/pupae (121 or 61.4% of Ae. aegypti and 76 or 38.6% of Ae. albopictus). This reduction was accompanied by a decrease in suspected human ZIKV cases from March to June 2015. The RT-qPCR performed in 18 pools identified that three (two of Ae. aegypti and one of Ae. albopictus) were positive for ZIKV, and none were positive for DENV or CHIKV. Our findings demonstrated that ZIKV was present in immature stages of insect vectors in the study region at least five months prior to the peak of ZIKV associated cases. Xenomonitoring of immature phases of the vectors may prove useful for predicting outbreaks.


Asunto(s)
Aedes/virología , Virus Chikungunya/aislamiento & purificación , Virus del Dengue/aislamiento & purificación , Mosquitos Vectores/virología , Virus Zika/aislamiento & purificación , Aedes/clasificación , Animales , Humanos , Mosquitos Vectores/clasificación , ARN Viral/análisis , Reacción en Cadena en Tiempo Real de la Polimerasa , Estaciones del Año , Infección por el Virus Zika/transmisión
16.
Int J Food Microbiol ; 311: 108349, 2019 Dec 02.
Artículo en Inglés | MEDLINE | ID: mdl-31634688

RESUMEN

Food-borne viral infections are caused mainly by noroviruses (NoV) and the hepatitis A virus (HAV), which respectively cause gastroenteritis and hepatitis. Various foods have been implicated in viral outbreaks, including vegetables that are consumed in a variety of forms, often with salad dressing. NF EN ISO procedures (15216-1:2017) propose standard methods for quantifying NoV and HAV in high-risk food categories, such as vegetables, based on viral elution and PEG concentration methods, but these methods are not suitable for composite meals like salads dressed with oily, fatty or emulsified food ingredients. The development of sensitive and reliable techniques for the detection of viruses in these products is therefore needed to ensure the safety of these products. The aim of this study was to develop an RT-qPCR based method for the detection and quantification of NoV and HAV in various vegetables with different dressings. Three methods for recovering NoV and HAV from artificially contaminated dressed vegetables were evaluated. The selected method was based on the use of Trizol reagent and, according to the type of dressing, the limit of detection ranged from 104 to 106 genome copies/g for NoV and from 102 to 103 PFU/g for HAV. The described method can be applied for detecting NoV and HAV in food containing salad dressing for routine diagnosis needs.


Asunto(s)
Contaminación de Alimentos/análisis , Microbiología de Alimentos/métodos , Virus de la Hepatitis A/aislamiento & purificación , Norovirus/aislamiento & purificación , Verduras/virología , Enfermedades Transmitidas por los Alimentos/prevención & control , Enfermedades Transmitidas por los Alimentos/virología , Gastroenteritis/prevención & control , Gastroenteritis/virología , Genoma Viral/genética , Virus de la Hepatitis A/genética , Humanos , Norovirus/genética , ARN Viral/análisis , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
17.
Klin Lab Diagn ; 64(9): 571-577, 2019.
Artículo en Ruso | MEDLINE | ID: mdl-31610111

RESUMEN

This study presents the results of laboratory trials of the reagent kit for the rapid detection of RNA of the Crimean-Congo hemorrhagic fever virus (CCHFV) using loop-mediated isothermal amplification with reverse transcription (RT-LAMP). The developed RT-LAMP reagent kit was used to detect the CCHFV and showed a sensitivity of 103 GE/ml of viral RNA, which is sufficient for detection of the CCHFV in the early stage of human infections. The kit showed high specificity and no cross-reactivity with viral panel from the State collection of viruses of the FBRI SRC VB «Vector¼ (arboviruses and hemorrhagic fever viruses). Laboratory trials of the RT-LAMP kit are showed a high analytical and diagnostic sensitivity and specificity for RNA detection of the CCHFV and high speed of the analysis (60-70 min with sample preparation) compared to real-time PCR. Approbation of the kit field version has showed the possibility of setting the RT-LAMP reaction and viral RNA detection without the using of analytical equipments.


Asunto(s)
Virus de la Fiebre Hemorrágica de Crimea-Congo/aislamiento & purificación , Fiebre Hemorrágica de Crimea/diagnóstico , Técnicas de Amplificación de Ácido Nucleico , Juego de Reactivos para Diagnóstico , Humanos , ARN Viral/análisis , Reacción en Cadena en Tiempo Real de la Polimerasa , Transcripción Reversa , Sensibilidad y Especificidad
18.
Pan Afr Med J ; 33: 169, 2019.
Artículo en Francés | MEDLINE | ID: mdl-31565130

RESUMEN

Introduction: hepatitis C virus (HCV) has several extra-hepatic manifestations including cryoglubulinemia. Cryoglobulinemia is defined as the abnormal presence in the blood of one or several proteins (cryoglobulins) that can precipitate at low temperatures. Method: We conducted a cross-sectional analytical study in the Laboratory of Biology and in the Unit of Hepatology of the General Hospital in Douala (HGD) over a period of 6 months. All patients agreeing to participate to the study and with anti-hepatitis-C antibodies under treatment or not were enrolled. Cryoglobulins were detected using biuret method and the classification was performed using Brouet immunoelectrophoresis. A multivariate analysis was conducted, confounding factors such as age, sex and the length of time after Hepatitis C Virus screening were adjusted. Results: The study enrolled 116 patients. The average age of patients was 58.47±9.95 years. Male sex accounted for 50.86% of cases. Arthralgia was found in 69.80% of cases. Cryoglobulin was found in 63.80% of patients. After adjustment, female sex (OR =2.18; CI 95% [0,97-4,90]; p= 0.059), asthenia alone (OR =2.45;CI 95% [1,04-5,80]; p= 0.041), asthenia combined with arthralgia (OR =2.84;CI 95% [1,13-7, 10]; p= 0.026) and the presence of HCV RNA (OR =2.84;CI 95% [1,13-7,10]; p= 0.028) were factors independently associated with the presence of cryoglobulin. Conclusion: The prevalence of cryoglobubin is high in patients with anti-hepatitis-C antibodies at the HGD. Simple biological methods are used to detect it. Cryoglobulin test in patients with HCV is essential in resource-limited countries.


Asunto(s)
Crioglobulinemia/epidemiología , Crioglobulinas/análisis , Anticuerpos contra la Hepatitis C/sangre , Hepatitis C/complicaciones , Anciano , Artralgia/epidemiología , Artralgia/etiología , Camerún , Estudios Transversales , Crioglobulinemia/virología , Femenino , Humanos , Inmunoelectroforesis , Masculino , Persona de Mediana Edad , Análisis Multivariante , Prevalencia , ARN Viral/análisis
19.
Prev Vet Med ; 172: 104772, 2019 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-31607414

RESUMEN

BackgroundDetection and characterization of viral RNA pathogens from fieldwork are challenging due to the instability of the RNA molecule. FTA cards® have proved useful for sample storage and latter identification of pathogens with importance for agricultural, animal and human health: however, for optimal handling, processing, and biosafety measures are not well-established. ObjectiveThis systematic review aims to summarize the reported effectiveness of FTA cards® for storage and transport of viral RNA, as well as the conditions for their handling and use in downstream processes. Finally, the biosafety measures required to protect researchers and clinical lab workers are considered. MethodsWe performed a systematic review following the PRISMA statement. We searched MEDLINE (PubMed), Scopus and Web of Science using the keywords "FTA cards" AND "RNA". Articles were screened by title and abstract, and after examination of inclusion and exclusion criteria, relevant information was extracted. The quality of the studies was assessed, and the evidence was qualitatively summarized. ResultsA total of 175 records were retrieved, and 11 additional documents were found by checking references of the eligible articles. A total of 47 articles were included. Samples from animals accounted for 38.3% of the publications, which identified viruses that cause disease in poultry, wild birds, suids, or bovids. Three different methods for RNA extraction were reported. Other factors that vary across reports include the size of RNA amplicon, storage temperature, and duration of storage. Only fourteen articles tested the inactivation of the virus on the FTA card®, and in one case, the virus remained infective. ConclusionFTA cards® could be a suitable option for RNA virus storage and transport for fieldwork in areas where proper conditions for RNA preservation are difficult to achieve. Three different protocols have been used for RNA detection from this matrix. Biospecimens in the form of dried blood spots should be considered potentially infectious unless specifically treated to inactivate viral pathogens.


Asunto(s)
Enfermedades de los Animales/diagnóstico , ARN Viral/análisis , Manejo de Especímenes/veterinaria , Animales , Manejo de Especímenes/métodos
20.
Adv Exp Med Biol ; 1172: 157-188, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31628656

RESUMEN

RIG-I-like receptors (RLRs) are an important family of pattern recognition receptors. They activate the immunological responses against viral infections by sensing RNAs in the cytoplasm. Recent studies provide significant insights into the activation and transduction mechanisms of RLRs family (members including RIG-I, MDA5, and LGP2). Here we review our current understanding of the structures of RLRs. Structural characterizations of RLRs family have revealed the mechanism of their actions at molecular level. The activation mechanisms of RIG-I and MDA5 are different, despite both of them have similar domain organizations and bind to dsRNA ligands. RIG-I, but not MDA5, adopts an auto-suppression conformation in the absence of RNA. In addition to ligand triggered receptor oligomerization, the activities of these receptors are also regulated by several posttranslational modifications, especially ubiquitination. Overall, these structural studies play critical roles in promoting the understanding of viral RNA recognition mechanisms by the host innate immune system, which also contribute to the designing of drugs for treatment of viral infection. However, much work remains to be done in studying the signaling pathway of MDA5 and LGP2, particularly by structural biology.


Asunto(s)
Proteína 58 DEAD Box , ARN Helicasas DEAD-box , Inmunidad Innata , ARN Viral , Animales , Proteína 58 DEAD Box/química , Proteína 58 DEAD Box/metabolismo , Humanos , Helicasa Inducida por Interferón IFIH1 , ARN Bicatenario/metabolismo , ARN Viral/análisis , ARN Viral/metabolismo , Transducción de Señal , Virosis/inmunología
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