2,477 research outputs found

    Effect of high-pressure processing to improve the safety and quality of an Quercus acorn beverage

    Get PDF
    The development of an acorn beverage can be an opportunity to increase the intake of bioactive compounds and add value to Quercus acorn. However, unprocessed plant-based beverages have a very short shelf-life and thermal treatments affect their overall quality. High-pressure processing (HPP) emerges as a possible solution to better retain nutritional properties and sensorial quality and extend shelf-life. This research assessed the impact of HPP (450/600 MPa, 5/12.5/20 min) and thermal processing (TP, 85 °C, 30 min) on an acorn beverage during 63 days of refrigerated storage (4 °C). From all processing conditions, HPP at 450 MPa for 5 min showed to be suitable to assure microbiological safety (mesophiles, psychrophiles, yeasts and moulds, and Enterobacteriaceae) during 63 days and to better preserve total soluble solids and colour. The antioxidant activity (ABTS/DPPH) was similar to higher for heat-treated samples, being gallic acid the main phenolic compound found in the beverage. Total carbohydrates, lipids, proteins, minerals, and fatty acids contents were similar for HPP and TP. This beverage revealed low thrombogenicity and atherogenicity indices, and potassium as the main mineral. Concluding, HPP extended the shelf-life of the beverage and improved the physicochemical quality, revealed by panellists preference, as revealed by sensorial analysis.info:eu-repo/semantics/publishedVersio

    Rapid and sensitive detection of Citrus Bacterial Canker by loop-mediated isothermal amplification combined with simple visual evaluation methods

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Citrus Bacterial Canker (CBC) is a major, highly contagious disease of citrus plants present in many countries in Asia, Africa and America, but not in the Mediterranean area. There are three types of Citrus Bacterial Canker, named A, B, and C that have different genotypes and posses variation in host range within citrus species. The causative agent for type A CBC is <it>Xanthomonas citri </it>subsp. <it>citri</it>, while <it>Xanthomonas fuscans </it>subsp. <it>aurantifolii</it>, strain B causes type B CBC and <it>Xanthomonas fuscans </it>subsp. <it>aurantifolii </it>strain C causes CBC type C. The early and accurate identification of those bacteria is essential for the protection of the citrus industry. Detection methods based on bacterial isolation, antibodies or polymerase chain reaction (PCR) have been developed previously; however, these approaches may be time consuming, laborious and, in the case of PCR, it requires expensive laboratory equipment. Loop-mediated isothermal amplification (LAMP), which is a novel isothermal DNA amplification technique, is sensitive, specific, fast and requires no specialized laboratory equipment.</p> <p>Results</p> <p>A loop-mediated isothermal amplification assay for the diagnosis of Citrus Bacterial Canker (CBC-LAMP) was developed and evaluated. DNA samples were obtained from infected plants or cultured bacteria. A typical ladder-like pattern on gel electrophoresis was observed in all positive samples in contrast to the negative controls. In addition, amplification products were detected by visual inspection using SYBRGreen and using a lateral flow dipstick, eliminating the need for gel electrophoresis. The sensitivity and specificity of the assay were evaluated in different conditions and using several sample sources which included purified DNA, bacterium culture and infected plant tissue. The sensitivity of the CBC-LAMP was 10 fg of pure <it>Xcc </it>DNA, 5 CFU in culture samples and 18 CFU in samples of infected plant tissue. No cross reaction was observed with DNA of other phytopathogenic bacteria. The assay was capable of detecting CBC-causing strains from several geographical origins and pathotypes.</p> <p>Conclusions</p> <p>The CBC-LAMP technique is a simple, fast, sensitive and specific method for the diagnosis of Citrus Bacterial Canker. This method can be useful in the phytosanitary programs of the citrus industry worldwide.</p

    Impacts of microcystins on morphological and physiological parameters of agricultural plants: a review

    Get PDF
    Cyanobacteria are a group of photosynthetic prokaryotes that pose a great concern in the aquatic environments related to contamination and poisoning of wild life and humans. Some species of cyanobacteria produce potent toxins such as microcystins (MCs), which are extremely aggressive to several organisms, including animals and humans. In order to protect human health and prevent human exposure to this type of organisms and toxins, regulatory limits for MCs in drinking water have been established in most countries. In this regard, the World Health Organization (WHO) proposed 1 µg MCs/L as the highest acceptable concentration in drinking water. However, regulatory limits were not defined in waters used in other applications/activities, constituting a potential threat to the environment and to human health. Indeed, water contaminated with MCs or other cyanotoxins is recurrently used in agriculture and for crop and food production. Several deleterious effects of MCs including a decrease in growth, tissue necrosis, inhibition of photosynthesis and metabolic changes have been reported in plants leading to the impairment of crop productivity and economic loss. Studies have also revealed significant accumulation of MCs in edible tissues and plant organs, which raise concerns related to food safety. This work aims to systematize and analyze the information generated by previous scientific studies, namely on the phytotoxicity and the impact of MCs especially on growth, photosynthesis and productivity of agricultural plants. Morphological and physiological parameters of agronomic interest are overviewed in detail in this work, with the aim to evaluate the putative impact of MCs under field conditions. Finally, concentration-dependent effects are highlighted, as these can assist in future guidelines for irrigation waters and establish regulatory limits for MCsinfo:eu-repo/semantics/publishedVersio

    Alternative transmission routes in the malaria elimination era: an overview of transfusion-transmitted malaria in the Americas

    Get PDF
    Submitted by Janaína Nascimento ([email protected]) on 2019-02-21T11:59:00Z No. of bitstreams: 1 ve_Alho_Regina_etal_INI_2017.pdf: 1190158 bytes, checksum: 8937322faefa31c89eb1bbd2f7d134a3 (MD5)Approved for entry into archive by Janaína Nascimento ([email protected]) on 2019-02-25T11:34:33Z (GMT) No. of bitstreams: 1 ve_Alho_Regina_etal_INI_2017.pdf: 1190158 bytes, checksum: 8937322faefa31c89eb1bbd2f7d134a3 (MD5)Made available in DSpace on 2019-02-25T11:34:33Z (GMT). No. of bitstreams: 1 ve_Alho_Regina_etal_INI_2017.pdf: 1190158 bytes, checksum: 8937322faefa31c89eb1bbd2f7d134a3 (MD5) Previous issue date: 2017Universidade do Estado do Amazonas. Manaus, AM, Brasil / Fundação de Hematologia e Hemoterapia do Amazonas. Manaus, AM, Brasil.Fundação de Medicina Tropical Dr. Heitor Vieira Dourado. Manaus, AM, Brasil.Universidade do Estado do Amazonas. Manaus, AM, Brasil / Fundação de Medicina Tropical Dr. Heitor Vieira Dourado. Manaus, AM, Brasil.Fundação de Hematologia e Hemoterapia do Amazonas. Manaus, AM, Brasil.Universidade do Estado do Amazonas. Manaus, AM, Brasil.Universidade do Estado do Amazonas. Manaus, AM, Brasil / Fundação de Medicina Tropical Dr. Heitor Vieira Dourado. Manaus, AM, Brasil.Sem afiliação.Fundação Oswaldo Cruz. Instituto Nacional de Infectologia Evandro Chagas. Rio de Janeiro, RJ, Brasil / Fundação Oswaldo Cruz. Instituto de Pesquisas Leônidas e Maria Deane. Manaus, AM, Brasil.Universidade do Estado do Amazonas. Manaus, AM, Brasil / Fundação de Medicina Tropical Dr. Heitor Vieira Dourado. Manaus, AM, Brasil.Universidade do Estado do Amazonas. Manaus, AM, Brasil / Fundação de Medicina Tropical Dr. Heitor Vieira Dourado. Manaus, AM, Brasil / Fundação Oswaldo Cruz. Instituto de Pesquisas Leônidas e Maria Deane. Manaus, AM, Brasil.Background: Transfusion-transmitted (TT) malaria is an alternative infection route that has gained little attention from authorities, despite representing a life-threatening condition. There has been no systematic review of this health problem in American countries. The aim of this study was to describe the clinical and epidemiological characteristics of TT malaria in the Americas and identify factors associated with lethality based on the studies published in the literature. Methods: Potentially relevant papers in all languages were retrieved from MEDLINE and LILACS. Additional articles were obtained from reviews and original papers. Publications on screening of candidate blood donors and on surveillance of TT malaria cases were included. Odds ratios with respective 95% confidence intervals (95% CI) were calculated. Epidemiological characteristics of blood donors of TT malaria cases, including a pooled positivity of different tests for malaria diagnosis, were retrieved. Results: A total of 63 publications regarding TT malaria from seven countries were included, from 1971 to 2016. A total of 422 cases of TT malaria were recorded. Most TT malaria cases were in females (62.0%) and 39.5% were in the ≥61 years-old age group. About half of all cases were from Mexico (50.7%), 40.3% from the United States of America (USA) and 6.6% from Brazil. Gyneco-obstetrical conditions (67.3%), surgical procedures (20.6%) and complications from neoplasias (6.1%) were the most common indications of transfusion. Packed red blood cells (RBCs) (50.7%) and whole blood (43.3%) were the blood products mostly associated with TT malaria. Cases were mostly caused by Plasmodium malariae (58.4%), followed by Plasmodium vivax (20.7%) and Plasmodium falciparum (17.9%). A total of 66.6% of cases were diagnosed by microscopy. Incubation period of 2–3 weeks was the most commonly observed (28.6%). Lethality was seen in 5.3% of cases and was associated with living in non-endemic countries, P. falciparum infection and concomitant neoplastic diseases. Conclusion: There is an important research and knowledge gap regarding the TT malaria burden in Latin American countries where malaria remains endemic. No screening method that is practical, affordable and suitably sensitive is available at blood banks in Latin American countries, where infections with low parasitaemia contribute greatly to transmission. Lethality from TT malaria was not negligible. TT malaria needs to be acknowledged and addressed in areas moving toward elimination

    Stress distribution of complete-arch implant-supported prostheses reinforced with silica-nylon mesh

    Get PDF
    This study evaluated the presence of a silica-nylon mesh and two cantilever lengths on the biomechanical behavior of complete-arch implant-supported prostheses. Twenty-four (24) complete mandibular arch implant-supported prostheses were divided into 4 groups according to the presence of reinforcing mesh (with or without) and the cantilever length (molar ? 15 mm or premolar ? 5 mm). The specimens were submitted to strain gauge analysis (30-kgf, 10 s) at different points (molar and premolar). Three-dimensional models were created based on the in vitro specimens, and the results in the bone (microstrain), prostheses (tensile stress), implants and prosthetic screws (von-Mises stress) were evaluated using the finite element method (FEM). All materials were considered homogeneous, isotropic and linear. Strain gauge data were submitted to 3-way analysis of variance and the Tukey test (?=.05). FEM results were qualitatively analyzed using colorimetric graphs. The microstrain magnitude for the prostheses with reinforcement was 519.91±359 and 583.33±661 without reinforcement (p=.001). The microstrain values for loading on the molar was 867.49±784 and on the premolar was 235.75±145. FEM corroborated with the in vitro findings for the bone behavior. The load application in the premolar showed reduced stress concentration, and a significant difference was observed between the presence or absence of the reinforcement for the prostheses. Silica-nylon mesh reduced the peri-implant microstrain and the prosthesis stress regardless of the cantilever extension. For temporary complete-arch implant-supported prostheses, the limitation of the cantilever to the premolar region improves the biomechanical response during load application

    Nonatobase: A Database For Polychaeta (annelida) From The Southwestern Atlantic Ocean.

    Get PDF
    Networks can greatly advance data sharing attitudes by providing organized and useful data sets on marine biodiversity in a friendly and shared scientific environment. NONATObase, the interactive database on polychaetes presented herein, will provide new macroecological and taxonomic insights of the Southwestern Atlantic region. The database was developed by the NONATO network, a team of South American researchers, who integrated available information on polychaetes from between 5°N and 80°S in the Atlantic Ocean and near the Antarctic. The guiding principle of the database is to keep free and open access to data based on partnerships. Its architecture consists of a relational database integrated in the MySQL and PHP framework. Its web application allows access to the data from three different directions: species (qualitative data), abundance (quantitative data) and data set (reference data). The database has built-in functionality, such as the filter of data on user-defined taxonomic levels, characteristics of site, sample, sampler, and mesh size used. Considering that there are still many taxonomic issues related to poorly known regional fauna, a scientific committee was created to work out consistent solutions to current misidentifications and equivocal taxonomy status of some species. Expertise from this committee will be incorporated by NONATObase continually. The use of quantitative data was possible by standardization of a sample unit. All data, maps of distribution and references from a data set or a specified query can be visualized and exported to a commonly used data format in statistical analysis or reference manager software. The NONATO network has initialized with NONATObase, a valuable resource for marine ecologists and taxonomists. The database is expected to grow in functionality as it comes in useful, particularly regarding the challenges of dealing with molecular genetic data and tools to assess the effects of global environment change. Database URL: http://nonatobase.ufsc.br/.2014bau00
    corecore