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1.
J Sci Food Agric ; 98(5): 1803-1812, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28873234

RESUMEN

BACKGROUND: Temperature changes and rainfall fluctuations affect the winemaking industry by altering vine phenology, crop yield, must composition and wine quality. Here, the evolution of the varietal aroma potential during ripening over three consecutive seasons has been analyzed considering climate conditions. The effect of season, ripening date and climatic conditions on aroma precursor accumulation in grapes was studied by multivariate analysis and discussed in regard to the potential aromatic quality of the wine. RESULTS: In contrast to musts obtained from grapes harvested in warm and dry seasons (2014 and 2015), musts obtained from grapes harvested in the coolest and most humid year (2013) showed a lower pH, higher total acidity, higher varietal aroma potential index (IPAv), and higher aromatic potential of linalool, geraniol and nerol (typical of the Muscat flavor). CONCLUSION: Considering the three seasons, grapes synthesized and accumulated more precursors when milder temperatures and late rains throughout veraison were recorded. However, we observed a high fluctuation of aroma precursors during the ripening period, so choosing the correct harvesting date (according to grape aroma potential) may overcome some of the negative effects linked to climate conditions. © 2017 Society of Chemical Industry.


Asunto(s)
Aromatizantes/química , Frutas/química , Glicoconjugados/química , Vitis/crecimiento & desarrollo , Clima , Frutas/crecimiento & desarrollo , Humanos , Odorantes/análisis , Estaciones del Año , Gusto , Temperatura , Vitis/química , Compuestos Orgánicos Volátiles/química , Vino/análisis
2.
Arch Insect Biochem Physiol ; 92(1): 38-64, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-27062414

RESUMEN

Emerging and re-emerging tick-borne diseases threaten public health and the wellbeing of domestic animals and wildlife globally. The adoption of an evolutionary ecology framework aimed to diminish the impact of tick-borne diseases needs to be part of strategies to protect human and animal populations. We present a review of current knowledge on the adaptation of ticks to their environment, and the impact that global change could have on their geographic distribution in North America. Environmental pressures will affect tick population genetics by selecting genotypes able to withstand new and changing environments and by altering the connectivity and isolation of several tick populations. Research in these areas is particularly lacking in the southern United States and most of Mexico with knowledge gaps on the ecology of these diseases, including a void in the identity of reservoir hosts for several tick-borne pathogens. Additionally, the way in which anthropogenic changes to landscapes may influence tick-borne disease ecology remains to be fully understood. Enhanced knowledge in these areas is needed in order to implement effective and sustainable integrated tick management strategies. We propose to refocus ecology studies with emphasis on metacommunity-based approaches to enable a holistic perspective addressing whole pathogen and host assemblages. Network analyses could be used to develop mechanistic models involving multihost-pathogen communities. An increase in our understanding of the ecology of tick-borne diseases across their geographic distribution will aid in the design of effective area-wide tick control strategies aimed to diminish the burden of pathogens transmitted by ticks.


Asunto(s)
Bioquímica , Genética de Población , Enfermedades por Picaduras de Garrapatas/epidemiología , Garrapatas/fisiología , Adaptación Biológica , Distribución Animal , Animales , Cambio Climático , Humanos , América del Norte/epidemiología , Enfermedades por Picaduras de Garrapatas/prevención & control , Garrapatas/química , Garrapatas/genética
3.
Sensors (Basel) ; 15(4): 8429-43, 2015 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-25871715

RESUMEN

Two novel applications using a portable and wireless sensor system (e-nose) for the wine producing industry-The recognition and classification of musts coming from different grape ripening times and from different grape varieties-Are reported in this paper. These applications are very interesting because a lot of varieties of grapes produce musts with low and similar aromatic intensities so they are very difficult to distinguish using a sensory panel. Therefore the system could be used to monitor the ripening evolution of the different types of grapes and to assess some useful characteristics, such as the identification of the grape variety origin and to prediction of the wine quality. Ripening grade of collected samples have been also evaluated by classical analytical techniques, measuring physicochemical parameters, such as, pH, Brix, Total Acidity (TA) and Probable Grade Alcoholic (PGA). The measurements were carried out for two different harvests, using different red (Barbera, Petit Verdot, Tempranillo, and Touriga) and white (Malvar, Malvasía, Chenin Blanc, and Sauvignon Blanc) grape musts coming from the experimental cellar of the IMIDRA at Madrid. Principal Component Analysis (PCA) and Probabilistic Neural Networks (PNN) have been used to analyse the obtained data by e-nose. In addition, and the Canonical Correlation Analysis (CCA) method has been carried out to correlate the results obtained by both technologies.

4.
medRxiv ; 2024 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-38946991

RESUMEN

Sepsis is the leading cause of death of hospitalized children worldwide. Despite the established link between immune dysregulation and mortality in pediatric sepsis, it remains unclear which host immune factors contribute causally to adverse sepsis outcomes. Identifying modifiable pathobiology is an essential first step to successful translation of biologic insights into precision therapeutics. We designed a prospective, longitudinal cohort study of 88 critically ill pediatric patients with multiple organ dysfunction syndrome (MODS), including patients with and without sepsis, to define subphenotypes associated with targetable mechanisms of immune dysregulation. We first assessed plasma proteomic profiles and identified shared features of immune dysregulation in MODS patients with and without sepsis. We then employed consensus clustering to define three subphenotypes based on protein expression at disease onset and identified a strong association between subphenotype and clinical outcome. We next identified differences in immune cell frequency and activation state by MODS subphenotype and determined the association between hyperinflammatory pathway activation and cellular immunophenotype. Using single cell transcriptomics, we demonstrated STAT3 hyperactivation in lymphocytes from the sickest MODS subgroup and then identified an association between STAT3 hyperactivation and T cell immunometabolic dysregulation. Finally, we compared proteomics findings between patients with MODS and patients with inborn errors of immunity that amplify cytokine signaling pathways to further assess the impact of STAT3 hyperactivation in the most severe patients with MODS. Overall, these results identify a potentially pathologic and targetable role for STAT3 hyperactivation in a subset of pediatric patients with MODS who have high severity of illness and poor prognosis.

5.
Microorganisms ; 11(7)2023 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-37512854

RESUMEN

Non-Saccharomyces yeasts represent a great source of biodiversity for the production of new beer styles, since they can be used in different industrial areas, as pure culture starters, in co-fermentation with Saccharomyces, and in spontaneous fermentation (lambic and gueuze production, with the main contribution of Brettanomyces yeast). The fermentation process of lambic beer is characterized by different phases with a characteristic predominance of different microorganisms in each of them. As it is a spontaneous process, fermentation usually lasts from 10 months to 3 years. In this work, an attempt was made to perform a fermentation similar to the one that occurred in this process with lactic bacteria, Saccharomyces yeast and Brettanomyces yeast, but controlling their inoculation and therefore decreasing the time necessary for their action. For this purpose, after the first screening in 100 mL where eight Brettanomyces yeast strains from D.O. "Ribeira Sacra" (Galicia) were tested, one Brettanomyces bruxellensis strain was finally selected (B6) for fermentation in 1 L together with commercial strains of Saccharomyces cerevisiae S-04 yeast and Lactobacillus brevis lactic acid bacteria in different sequences. The combinations that showed the best fermentative capacity were tested in 14 L. Volatile compounds, lactic acid, acetic acid, colour, bitterness, residual sugars, ethanol, melatonin and antioxidant capacity were analysed at different maturation times of 1, 2, 6 and 12 months. Beers inoculated with Brettanomyces yeast independently of the other microorganisms showed pronounced aromas characteristic of the Brettanomyces yeast. Maturation after 12 months showed balanced beers with "Brett" aromas, as well as an increase in the antioxidant capacity of the beers.

6.
Front Biosci (Elite Ed) ; 15(3): 18, 2023 07 17.
Artículo en Inglés | MEDLINE | ID: mdl-37743229

RESUMEN

BACKGROUND: In the search of tools to deal with climate change-related effects along with the aim of avoiding the loss of aromatic typicity in wine, two native yeasts strains of Saccharomyces cerevisiae (CLI 271 and CLI 889) were evaluated to determine their influence on white Malvasia aromatica wines aroma composition and sensory characteristics. METHODS: The strains were tested versus a commercial yeast strain (LSA). The fermentations were performed on grape must of the Malvasia aromatica variety previously macerated. Wine quality was studied by analysis of oenological parameters together with volatile aroma components using gas chromatography coupled to flame ionization detector (GC-FID) to quantify major volatiles compounds and headspace-solid phase microextraction coupled with gas chromatography-mass spectrometry (HS-SPME/GC-MS) to determine terpenoids and C13-norisoprenoids. Sensorial analysis was also realized by an experienced taster panel. RESULTS: Wines from locally-selected yeasts strains used had lower volatile acidity levels and higher concentration of aromatic compounds compared to the commercial strain ones. The yeast strain S. cerevisiae CLI 271 provided wines with a higher concentration of esters related to fruity attributes, especially isoamyl acetate. The tasting panel highlighted the strong floral character of wines from S. cerevisiae CLI 889 fermentation. CONCLUSIONS: The use of microorganisms well adapted to climatic conditions can be used to produce quality wines of the Malvasia aromatica variety.


Asunto(s)
Saccharomyces cerevisiae , Vino , Ésteres , Fermentación , Norisoprenoides
7.
Trop Med Infect Dis ; 8(7)2023 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-37505636

RESUMEN

A limited number of longitudinal studies have examined the symptoms associated with long-COVID-19. We conducted an assessment of symptom onset, severity and patient recovery, and determined the percentage of patients who experienced reinfection up to 2 years after the initial onset of the disease. Our cohort comprises 377 patients (≥18 years) with laboratory-confirmed COVID-19 in a secondary hospital (Madrid, Spain), throughout March 3-16, 2020. Disease outcomes and clinical data were followed-up until August 12, 2022. We reviewed the evolution of the 253 patients who had survived as of April 2020 (67.1%). Nine died between April 2020 and August 2022. A multivariate regression analysis performed to detect the risk factors associated with long-COVID-19 revealed that the increased likelihood was associated with chronic obstructive lung disease (OR 14.35, 95% CI 1.89-109.09; p = 0.010), dyspnea (5.02, 1.02-24.75; p = 0.048), higher LDH (3.23, 1.34-7.52; p = 0.006), and lower D-dimer levels (0.164, 0.04-0.678; p = 0.012). Reinfected patients (n = 45) (47.8 years; 39.7-67.2) were younger than non-reinfected patients (64.1 years; 48.6-74.4)) (p < 0.001). Patients who received a combination of vaccines exhibited fewer symptoms (44.4%) compared to those who received a single type of vaccine (77.8%) (p = 0.048). Long-COVID-19 was detected in 27.05% (66/244) of patients. The early detection of risk factors helps predict the clinical course of patients with COVID-19. Middle-aged adults could be susceptible to reinfection, highlighting the importance of prevention and control measures regardless of vaccination status.

8.
Am J Bot ; 99(7): 1146-57, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22763354

RESUMEN

PREMISE OF THE STUDY: The poinsettia (Euphorbia pulcherrima) is the world's most economically important potted plant, but despite its preeminence it is not clear which wild populations are ancestral to the varieties cultivated around the world. Tradition holds that the U.S. envoy to Mexico J. R. Poinsett collected the progenitors of the over 300 varieties in global cultivation on an 1828 excursion to northern Guerrero State, Mexico. It is unknown whether the contemporary cultivars are descended from plants from Guerrero or whether germplasm from other parts of poinsettia's 2000 km long distribution entered into cultivation during the nearly 200 yr of subsequent poinsettia horticulture. METHODS: To identify the wild populations that likely gave rise to the cultivars and test this historical account, we sequenced plastid and nuclear DNA regions and modeled poinsettia's potential distribution. KEY RESULTS: The combination of nuclear and plastid haplotypes characterizing cultivars was found only in northern Guerrero. Distribution modeling indicated that suitable habitat conditions for wild poinsettias are present in this area, consistent with their likely wild status. CONCLUSIONS: Our data pinpoint the area of northern Guerrero as the cultivated poinsettia's probable ancestral region, congruent with the traditional account attributing the original collections to Poinsett. Abundant genetic variation likely offers raw material for improving the many shortcomings of cultivars, including vulnerability to cold, stem breakage, and pathogens such as Pythium and Phytophthora. However, genetic differences between populations make conservation of all of poinsettia's diversity difficult.


Asunto(s)
Euphorbia/genética , Jardinería/historia , Conservación de los Recursos Naturales , ADN de Plantas/genética , Ecosistema , Gliceraldehído-3-Fosfato Deshidrogenasas/genética , Historia del Siglo XIX , México , Filogeografía , Plastidios/genética , Análisis de Secuencia de ADN , Clima Tropical
9.
Foods ; 11(14)2022 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-35885271

RESUMEN

The use of non-Saccharomyces yeasts in brewing is a useful tool for developing new products to meet the growing consumer demand for innovative products. Non-Saccharomyces yeasts can be used both in single and in mixed fermentations with Saccharomyces cerevisiae, as they are able to improve the sensory profile of beers, and they can be used to obtain functional beers (with a low ethanol content and melatonin production). The aim of this study was to evaluate this capacity in eight non-Saccharomyces strains isolated from Madrid agriculture. For this purpose, single fermentations were carried out with non-Saccharomyces strains and sequential fermentations with non-Saccharomyces and the commercial strain SafAle S-04. The Wickerhamomyces anomalus strain CLI 1028 was selected in pure culture for brewing beer with a low ethanol content (1.25% (v/v)) for its fruity and phenolic flavours and the absence of wort flavours. The best-evaluated strains in sequential fermentation were CLI 3 (Hanseniaspora vineae) and CLI 457 (Metschnikowia pulcherrima), due to their fruity notes as well as their superior bitterness, body, and balance. Volatile compounds and melatonin production were analysed by GC and HPLC, respectively. The beers were sensory-analysed by a trained panel. The results of the study show the potential of non-Saccharomyces strains in the production of low-alcohol beers, and as a flavour enhancement in sequential fermentation.

10.
Foods ; 11(22)2022 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-36429309

RESUMEN

The use of wild yeasts, isolated from different environments, is becoming the most interesting option for the production of new beers. The objective of this study is to evaluate the potential of seven non-conventional yeast strains from five different species (Saccharomyces cerevisiae, Hanseniaspora guilliermondii, Metschnikowia pulcherrima, Torulaspora delbrueckii, and Zygosaccharomyces bailii) isolated from Madrid agriculture to produce type ale beer. Wild yeast strains were evaluated at laboratory and pilot plant scales under different fermentation conditions (pure, aerated, and sequential culture). Strain S. cerevisiae SafAle S-04 was used as a reference. Throughout the fermentation of beer, volatile compounds were determined by GC and residual sugars by HPLC, among other parameters. The yeast strains used for the fermentation in pure culture conditions were unable to ferment maltose and maltotriose (0.73-1.18% v/v of ethanol). The results of the study under aerated conditions showed varying levels of higher alcohol and ester concentrations. It should be noted that the strain CLI 1057 (S. cerevisiae) fermented maltose in the presence of oxygen (Kluyver effect). This strain also showed a high production of 4-vinyl guaiacol, making it suitable for producing beers with a phenolic profile. Finally, three strains (H. guilliermondii, Z. bailii, and T. delbrueckii) were evaluated in sequential culture together with commercial strain and found to improve the organoleptic characteristics of the brewed beer. These approaches offer the opportunity to add new product characteristics to the beers.

11.
Front Epidemiol ; 2: 889280, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-38455276

RESUMEN

Chronic wasting disease (CWD) is a spongiform encephalopathy disease caused by the transmission of infectious prion agents. CWD is a fatal disease that affects wild and farmed cervids in North America with few cases reported overseas. Social interaction of cervids, feeding practices by wildlife keepers and climate effects on the environmental carrying capacity all can affect CWD transmission in deer. Wildlife deer game hunting is economically important to the semi-arid South Texas region and is affected by climate change. In this paper, we model and investigate the effect of climate change on the spread of CWD using typical climate scenarios. We use a system of impulsive differential equations to depict the transmission of CWD between different age groups and gender of cervids. The carrying capacity and contact rates are assumed to depend on climate. Due to the polygamy of bucks, we use mating rates that depend on the number of bucks and does. We analyze the stability of the model and use simulations to study the effect of harvesting (culling) on eradicating the disease, given the climate of South Texas. We use typical climate change scenarios based on published data and our assumptions. For the climate indicator, we calculated and utilized the Standard Precipitation Evapotranspiration Index (SPEI). We found that climate change might hinder the efforts to reduce and effectively manage CWD as it becomes endemic to South Texas. The model shows the extinction of the deer population from this region is a likely outcome.

12.
Pathogens ; 10(8)2021 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-34451456

RESUMEN

Aedes aegypti and Aedes albopictus (Diptera: Culicidae) are vectors for several arboviruses, including dengue, Zika virus and chikungunya virus. The primary method of controlling these diseases is controlling the vector population, often with insecticides. Insecticide resistance may impact the success of these efforts. We tested the effect of variable temperature exposures on susceptibility to insecticides by exposing adult A.aegypti and A. albopictus to different temperatures and tested their susceptibility to insecticides. We hypothesized that adults maintained at high temperatures would show increased susceptibility to insecticides relative to lower temperatures. Colony mosquitoes were hatched, reared to adulthood and then maintained in three temperature regimes that reflect average seasonal temperatures in the Rio Grande Valley, TX. Susceptibility to permethrin and deltamethrin was assessed using the CDC bottle bioassay method. Overall Aedes albopictus had higher susceptibility to all insecticides than Aedes aegypti. Mosquitoes kept at different temperatures exhibited differential susceptibility to insecticides. Low temperature exposed mosquitoes had decreased susceptibility while high temperature conditions resulted in increased mortality. Our results suggest public health officials must consider temperature effects when controlling mosquitoes with insecticides.

13.
J Virol Methods ; 289: 114047, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33338544

RESUMEN

OBJECTIVES: Serologic techniques can serve as a complement to diagnose SARS-CoV-2 infection. The objective of our study was to compare the diagnostic performance of six immunoassays to detect antibodies against SARS-CoV-2: three lateral flow immunoassays (LFAs), one ELISA and two chemiluminescence assays (CLIAs). METHODS: We evaluated three LFAs (Alltest, One Step and SeroFlash), one ELISA (Dia.Pro) and two CLIAs (Elecsys and COV2T). To assess the specificity, 60 pre-pandemic sera were used. To evaluate the sensitivity, we used 80 serum samples from patients with positive PCR for SARS-CoV-2. Agreement between techniques was evaluated using the kappa score (k). RESULTS: All immunoassays showed a specificity of 100 % except for SeroFlash (96.7 %). Overall sensitivity was 61.3 %, 73.8 %, 67.5 %, 85.9 %, 88.0 % and 92.0 % for Alltest, One Step, SeroFlash, Dia.Pro, Elecsys and COV2T, respectively. Sensitivity increased throughout the first two weeks from the onset of symptoms, reaching sensitivities over 85 % from 14 days for all LFAs, being One Step the most sensitive (97.6 %), followed by SeroFlash (95.1 %). Dia.Pro, Elecsys and COV2T showed sensitivities over 97 % from 14 days, being 100 % for COV2T. One Step showed the best agreement results among LFAs, showing excellent agreement with Dia.Pro (agreement = 94.2 %, k = 0.884), COV2T (99.1 %, k = 0.981) and Elecsys (97.3 %, k = 0.943). Dia.Pro, COV2T and Elecsys also showed excellent agreement between them. CONCLUSIONS: One Step, Dia.Pro, Elecsys and COV2T obtained the best diagnostic performance results. All these techniques showed a specificity of 100 % and sensitivities over 97 % from 14 days after the onset of symptoms, as well as excellent levels of agreement.


Asunto(s)
Anticuerpos Antivirales/sangre , Prueba Serológica para COVID-19/métodos , COVID-19/diagnóstico , Inmunoensayo/métodos , Inmunoglobulina G/sangre , Adulto , Anciano , Anciano de 80 o más Años , COVID-19/inmunología , Femenino , Humanos , Masculino , Persona de Mediana Edad , SARS-CoV-2 , Sensibilidad y Especificidad , Adulto Joven
14.
J Clin Virol ; 137: 104781, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33639492

RESUMEN

OBJECTIVES: Antigen rapid diagnostic tests (Ag-RDT) have been developed as reliable tools to control the SARS-CoV-2 pandemic. The objective of our study was to evaluate the diagnostic performance of two Ag-RDTs. METHODS: We evaluated CerTest SARS-CoV-2 Ag One Step Card Test and Panbio COVID-19 Ag Rapid Test Device Ag-RDTs. We included 320 nasopharyngeal samples: 150 PCR negative samples to assess the specificity and 170 PCR positive samples to evaluate the sensitivity. We also evaluated their sensitivity according to cycle threshold (Ct) values and the time from the onset of symptoms. Tests were compared using the McNemar's test and agreement was evaluated using the kappa score (k). RESULTS: Both Ag-RDTs showed a specificity of 100 %. Overall sensitivity was 53.5 % for CerTest and 60.0 % for Panbio. For samples with Ct≤ 25, sensitivity was 94.0 % for CerTest and 96.4 % for Panbio (p = 0.500). Regarding samples with Ct>25, sensitivity was 14.0 % for CerTest and 24.4 % for Panbio (p = 0.004). Sensitivity for samples within the first 5 days after the onset of symptoms were 84.8 % for CerTest and 91.3 % for Panbio (p = 0.250) and notably decreased for samples taken after the fifth day. Both Ag-RDTs showed an excellent agreement between them (agreement = 96.7 %, k = 0.920). Agreement with PCR was also excellent for high viral load samples (Ct<25) for CerTest (98.0 %, k = 0.954) and Panbio (98.8 %, k = 0.973). CONCLUSIONS: CerTest SARS-CoV-2 and Panbio COVID-19 Ag showed excellent performance and agreement results for samples with high viral loads (Ct ≤ 25) or samples taken within the first 5 days after the onset of symptoms.


Asunto(s)
Prueba de COVID-19/métodos , COVID-19/diagnóstico , SARS-CoV-2/aislamiento & purificación , Adulto , Anciano , Anticuerpos Antivirales/análisis , Antígenos Virales/análisis , Prueba de Ácido Nucleico para COVID-19/métodos , Pruebas Diagnósticas de Rutina , Femenino , Humanos , Masculino , Persona de Mediana Edad , Nasofaringe/virología , Sensibilidad y Especificidad , Pruebas Serológicas/métodos , Carga Viral
15.
Ticks Tick Borne Dis ; 12(6): 101812, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34416565

RESUMEN

Amblyomma mixtum is a Neotropical generalist tick of medical and veterinary importance which is widely distributed from United States of America to Ecuador. The aim of this study was to evaluate changes in the geographic projections of the ecological niche models of A. mixtum in climate change scenarios in America. We constructed a database of published scientific publications, personal collections, personal communications, and online databases. Ecological niche modelling was performed with 15 Bioclimatic variables using kuenm in R and was projected to three time periods (Last Glacial Maximum, Current and 2050) for America. Our model indicated a wide distribution for A. mixtum, with higher probability of occurrence along the Gulf of Mexico and occurring in a lesser proportion in the Pacific states, Central America, and the northern part of South America. The areas of new invasion are located mainly on the border of Mexico with Guatemala and Belize, some regions of Central America and Colombia. We conclude that the ecological niche modelling are effective tools to infer the potential distribution of A. mixtum in America, in addition to helping to propose future measures of epidemiological control and surveillance in the new potential areas of invasion.


Asunto(s)
Amblyomma/fisiología , Distribución Animal , Cambio Climático , Ecosistema , Animales , América Central , Modelos Biológicos , América del Norte , América del Sur
16.
J Clin Virol ; 133: 104659, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-33160179

RESUMEN

BACKGROUND: RT-qPCR is the current recommended laboratory method to diagnose SARS-CoV-2 acute infection, several factors such as requirement of special equipment, time consuming, high cost and skilled staff limit the use of these techniques. A more rapid and high-throughput method is essential. METHODS: We analyzed clinical data and nasopharyngeal samples, collected during September 2020, from patients attended at the emergency department of a secondary hospital and in two primary healthcare centers in Madrid. The performance of the Panbio™ COVID-19 AG Rapid Test Device for the detection of SARS-CoV-2 antigen was compared to RT-qPCR. RESULTS: 255 nasopharyngeal swabs, including 150 from the emergency department and 105 from primary helthcare centers, were tested. 184 patients were symptomatic (72.1 %). Amongst the 60 positive RT-qPCR samples, 40 were detected by the rapid antigen test, given an overall sensitivity of 73.3 %. All the samples detected positive with the rapid antigen test were also positive with RT-qPCR. The median cycle threshold was 23.28 (IQR 18.5-30.16). Patients with less than seven days onset of symptoms showed a higher viral load, and sensitivity for rapid antigen test (86.5 %), compared to those with more days (sensitivity of 53.8 %)(p < 0.004). CONCLUSIONS: The rapid antigen test evaluated in this study showed a high sensitivity and specificity in samples obtained during the first week of symptoms and with high viral loads. This assay seems to be an effective strategy for controlling the COVID-19 pandemic for the rapid identification and isolation of SARS-CoV-2 infected patients.


Asunto(s)
Antígenos Virales/análisis , Prueba de COVID-19/métodos , COVID-19/diagnóstico , Adulto , Anciano , COVID-19/inmunología , Diagnóstico Precoz , Femenino , Humanos , Inmunoensayo , Masculino , Persona de Mediana Edad , Nasofaringe/virología , Pruebas en el Punto de Atención , Juego de Reactivos para Diagnóstico , Sensibilidad y Especificidad , Carga Viral
17.
J Clin Virol ; 129: 104473, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32504945

RESUMEN

OBJECTIVES: SARS-CoV-2 infection diagnosis is challenging in patients from 2 to 3 weeks after the onset of symptoms, due to the low positivity rate of the PCR. Serologic tests could be complementary to PCR in these situations. The aim of our study was to analyze the diagnostic performance of one serologic rapid test in COVID-19 patients. METHODS: We evaluated a lateral flow immunoassay (AllTest COVID-19 IgG/IgM) which detects IgG and IgM antibodies. We validated the serologic test using serum samples from 100 negative patients (group 1) and 90 patients with COVID-19 confirmed by PCR (group 2). Then, we prospectively evaluated the test in 61 patients with clinical diagnosis of pneumonia of unknown etiology that were negative for SARS-CoV-2 by PCR (group 3). RESULTS: All 100 patients from group 1 were negative for the serologic test (specificity = 100 %). Regarding group 2 (PCR-positive), the median time from their symptom onset until testing was 17 days. For these 90 group-2 patients, the test was positive for either IgM or IgG in 58 (overall sensitivity = 64.4 %), and in patients tested 14 days or more after the onset of symptoms, the sensitivity was 88.0 %. Regarding the 61 group-3 patients, median time after symptom onset was also 17 days, and the test was positive in 54 (88.5 % positivity). CONCLUSIONS: Our study shows that Alltest lateral flow immunoassay is reliable as a complement of PCR to diagnose SARS-CoV-2 infection after 14 days from the onset of symptoms and in patients with pneumonia and negative PCR for SARS-CoV-2.


Asunto(s)
Anticuerpos Antivirales/sangre , Betacoronavirus/inmunología , Técnicas de Laboratorio Clínico/métodos , Infecciones por Coronavirus/diagnóstico , Inmunoensayo/métodos , Neumonía Viral/diagnóstico , Pruebas Serológicas/métodos , Anciano , COVID-19 , Prueba de COVID-19 , Femenino , Humanos , Inmunoglobulina G/sangre , Inmunoglobulina M/sangre , Masculino , Persona de Mediana Edad , Pandemias , Estudios Prospectivos , SARS-CoV-2 , Sensibilidad y Especificidad , Factores de Tiempo
18.
Ticks Tick Borne Dis ; 11(3): 101368, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-31917128

RESUMEN

The cattle tick, Rhipicephalus annulatus (Say) is a vector of bovine babesiosis and responsible for direct and indirect losses to cattle producing areas located in temperate and subtropical dry regions. Resistance against pyrethroids has been reported for this species in Asia and Africa, but never before in North America. An outbreak strain, Rio Lado, collected close to the border between Mexico and the United States, in Maverick County, Texas, showed low level of resistance to permethrin, a pyrethroid pesticide. We used genomic material from different strains of cattle ticks collected within the Permanent Quarantine Zone (Rio Lado, Vega and Klein Grass strains) to partially characterize the coding gene of the voltage-gated sodium channel (Na-channel), target-site of pyrethroid pesticides, and search for putative mutations associated with resistance using quantitative PCR high resolution melt (HRM) analysis. The two amplified fragments, corresponding to domains II and III of the Na-channel, were 100 % identical to its ortholog in Rhipicephalus microplus (Canestrini). No nucleotide polymorphisms in the Na-channel gene were observed in the pyrethroid-resistant Rio Lado strain, when compared to the susceptible strains Klein Grass and Vega. This study reports the first case of pyrethroid resistance in R. annulatus collected in the United States. Also, we provide new genomic data for this species of tick that allows for the development of a new method to screen for mutations associated with pyrethroid resistance.


Asunto(s)
Acaricidas/farmacología , Proteínas de Artrópodos/genética , Resistencia a Medicamentos/genética , Permetrina/farmacología , Rhipicephalus/fisiología , Canales de Sodio Activados por Voltaje/genética , Secuencia de Aminoácidos , Animales , Proteínas de Artrópodos/química , Proteínas de Artrópodos/metabolismo , Secuencia de Bases , Femenino , Larva/genética , Larva/crecimiento & desarrollo , Larva/fisiología , Rhipicephalus/genética , Rhipicephalus/crecimiento & desarrollo , Canales de Sodio Activados por Voltaje/química , Canales de Sodio Activados por Voltaje/metabolismo
19.
Conserv Biol ; 23(5): 1156-66, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19453656

RESUMEN

The national systems used in the evaluation of extinction risk are often touted as more readily applied and somehow more regionally appropriate than the system of the International Union for Conservation of Nature (IUCN). We compared risk assessments of the Mexican national system (method for evaluation of risk of extinction of wild species [MER]) with the IUCN system for the 16 Polianthes taxa (Agavaceae), a genus of plants with marked variation in distribution sizes. We used a novel combination of herbarium data, geographic information systems (GIS), and species distribution models to provide rapid, repeatable estimates of extinction risk. Our GIS method showed that the MER and the IUCN system use similar data. Our comparison illustrates how the IUCN method can be applied even when all desirable data are not available, and that the MER offers no special regional advantage with respect to the IUCN regional system. Instead, our results coincided, with both systems identifying 14 taxa of conservation concern and the remaining two taxa of low risk, largely because both systems use similar information. An obstacle for the application of the MER is that there are no standards for quantifying the criteria of habitat condition and intrinsic biological vulnerability. If these impossible-to-quantify criteria are left out, what are left are geographical distribution and the impact of human activity, essentially the considerations we were able to assess for the IUCN method. Our method has the advantage of making the IUCN criteria easy to apply, and because each step can be standardized between studies, it ensures greater comparability of extinction risk estimates among taxa.


Asunto(s)
Asparagaceae , Extinción Biológica , Sistemas de Información Geográfica , Asparagaceae/clasificación , Ecosistema , México , Especificidad de la Especie
20.
J Econ Entomol ; 112(3): 1167-1174, 2019 05 22.
Artículo en Inglés | MEDLINE | ID: mdl-30869131

RESUMEN

Management of Diaphorina citri Kuwayama (Hemiptera: Liviidae) populations is one of the major strategies for reducing the spread and incidence of huanglongbing (HLB). HLB is putatively caused by Candidatus Liberibacter spp. (Rhizobiales: Phyllopbacteriaceae) that are transmitted to citrus by psyllid vectors. Diaphorina citri population monitoring is done to detect its presence and inform on management decisions. Various methods are used for detecting and estimating D. citri densities but trapping with yellow or lime-green sticky cards has proven to be the most effective method. These sticky cards rely on the color preference of adult D. citri, but many flying organisms are attracted to the same color spectrum as psyllids. Hence, in field situations, sticky traps are hampered by large numbers of bycatches of nontarget organisms and debris. Here, we described a method using a mesh laid on the surface of traps as a sift to catch mainly psyllids, while reducing bycatches. By filtering D. citri through this mesh, they can be counted more rapidly and accurately. Although mesh-covered traps captured 5-15% less D. citri relative to uncovered ACP traps, both types of traps statistically agreed on D. citri detection and population densities. The effectiveness of mesh-covered traps did not vary with season. In addition, mesh-covered traps eliminated >90% of nontarget organisms and allowed for quicker enumeration of D. citri. We expect this method will become an important component of redesigning integrated pest management programs in citrus groves by reducing unintended impacts of beneficial arthropods during large scale D. citri monitoring.


Asunto(s)
Citrus , Hemípteros , Rhizobiaceae , Animales , Densidad de Población , Estaciones del Año
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