1,555 research outputs found
Synthetic Peptides as an Alternative Tool for the Diagnosis of Cryptococcosis
Cryptococcosis is an important systemic mycosis that threatens the lives of humans and animals. The disease is caused by two species of the genus Cryptococcus: Cryptococcus neoformans and Cryptococcus gattii. The diagnosis of cryptococcosis is made through microscopy, fungal culture followed by biochemical tests, and detection of the cryptococcal capsular antigen (CrAg). Despite the existence of an established diagnostic protocol, the search for new diagnostic tests is necessary due to the high incidence of the disease, with estimates of approximately 1 million cases of cryptococcal meningitis per year and more than 600,000 deaths in patients infected with human immunodeficiency virus (HIV), the potential for C. gattii to cause the disease in immunocompetent individuals, and the disease’s rapid worldwide dissemination. With the development of biotechnology, synthetic peptides have opened up new possibilities as a source of pure epitopes and molecules for the diagnosis of various diseases, based on the detection of circulating antibodies. Synthetic peptides can also be used for the development of vaccines. Studies on Leishmaniasis, Chagas disease, paracoccidioidomycosis, tuberculosis, and, more recently, on cryptococcosis, among others, have shown that this approach shows potential for the early diagnosis of the disease, thus reducing the morbi-lethality of individuals affected by this infection and ultimately changing their prognosis
Genótipos do vírus da hepatite C em pacientes em hemodiálise no Distrito Federal, Brasil
Hepatitis C virus (HCV) genotypes and subtypes were determined in hemodialysis patients in the Federal District, Brazil, by sequencing of the 5' noncoding (NC) and nonstructural 5B (NS5B) regions. From 761 patients, 66 anti-HCV-positive samples were tested for HCV RNA. All 51 HCV RNA-positive samples by PCR of the 5' NC region were genotyped as genotypes 1 (90.2%) and 3 (9.8%). Subtype 1a (82.3%) was the most prevalent, followed by subtypes 3a (9.8%), 1b (5.9%) and 1a/1b (2.0%). Forty-two samples could be amplified and genotyped in the NS5B region: 38 (90.5%) as genotype 1, subtypes 1a, and 8 (9.5%) as genotype 3, subtype 3a. For the 42 samples sequenced in both regions, the genotypes and subtypes determined were concordant in 100% and 95.2% of cases, respectively. Two samples presented discrepant results, with the 5' NC region not distinguishing correctly the subtypes 1a and 1b. These findings indicate that the HCV genotype 1, subtype 1a, is the most prevalent among hemodialysis patients in the Federal District, Brazil.Os genótipos e subtipos do vírus da hepatite C (HCV) foram determinados em pacientes em hemodiálise no Distrito Federal, Brasil, pelo sequenciamento das regiões 5' não codificante (NC) e não estrutural 5B (NS5B). De 761 pacientes, 66 amostras anti-HCV positivas foram testadas para RNA-HCV. Todas as 51 amostras RNA-HCV positivas por PCR para a região 5' NC foram genotipadas como dos genótipos 1 (90,2%) e 3 (9,8%). O subtipo 1a (82,3%) foi o mais prevalente, seguido pelos subtipos 3a (9,8%), 1b (5,9%) e 1a/1b (2,0%). Quarenta e duas amostras puderam ser amplificadas e genotipadas na região NS5B: 38 (90,5%) como genótipo 1, subtipo 1a, e 8 (9,5%) como genótipo 3, subtipo 3a. Para as 42 amostras sequenciadas nas duas regiões, os genótipos e subtipos determinados foram concordantes em 100% e 95,2% dos casos, respectivamente. Duas amostras apresentaram resultados discrepantes, sendo que a região 5' NC não diferenciou corretamente os subtipos 1a e 1b. Estes achados indicam que o genótipo 1, subtipo 1a, do HCV é o mais prevalente em pacientes em hemodiálise no Distrito Federal, Brasil
Food By-Product Valorization by Using Plant-Based Coagulants Combined with AOPs for Agro-Industrial Wastewater Treatment
Re-using and adding value to by-products is one of the current focuses of the agri-food
industry, following the Sustainable Development Goals of United Nations. In this work, the byproducts
of four plants, namely chestnut burr, acorn peel, olive leaf, and grape stem were used as
coagulants to treat elderberry wastewater (EW), a problematic liquid effluent. EW pre-treatment using
these natural coagulants showed promising results after pH and coagulant dosage optimization.
However, the decrease in total organic carbon (TOC) was not significant, due to the addition of
the plant-based natural coagulants which contain carbon content. After this pre-treatment, the
photo-Fenton advanced oxidation process was selected, after preliminary assays, to improve the
global performance of the EW treatment. Photo-Fenton was also optimized for the parameters of
pH, H2O2, Fe2+, and irradiance power, and the best conditions were applied to the EW treatment.
Under the best operational conditions defined in the parametric study, the combined results of
coagulation–flocculation–decantation (CFD) and photo-Fenton for chestnut burr, acorn peel, olive
leaf, and grape stem were, respectively, 90.2, 89.5, 91.5, and 88.7% for TOC removal; 88.7, 82.0, 90.2
and 93.1%, respectively, for turbidity removal; and finally, 40.6, 42.2, 45.3, and 39.1%, respectively, for
TSS removal. As a final remark, it is possible to suggest that plant-based coagulants, combined with
photo-Fenton, can be a promising strategy for EW treatment that simultaneously enables valorization
by adding value back to food by-productsinfo:eu-repo/semantics/publishedVersio
Avaliação do efeito fertilizante de um composto.
Comunicação da qual só está disponível o resumo.O presente trabalho foi desenvolvido na Escola Superior Agrária e teve como principal objetivo efetuar a validação de um composto como matéria fertilizante. O composto foi obtido pela compostagem dos seguintes resíduos de origem orgânica: lamas de depuração urbanas provenientes de ETAR e estruturante, que consiste
essencialmente de casca de pinho e madeira triturada (serrim). Para concretizar este objetivo realizaram-se os seguintes trabalhos experimentais: 1- Caracterização analítica do composto; 2- Ensaio de germinação, com a finalidade de demonstrar que o composto, após incorporação no solo, não afeta negativamente a germinação das sementes (1) ; 3- Ensaio em vasos, com um solo representativo das condições edáficas em Portugal e utilizando como cultura uma espécie forrageira (azevém, Lolium spp.). Este ensaio teve com o objetivo avaliar o efeito fertilizante do composto sobre as propriedades do solo e sobre a produção e qualidade da cultura. Verificou-se que o composto está conforme os valores exigidos pelo Decreto-Lei nº103/2015 de 15 de junho (2) para a colocação no mercado de matérias fertilizantes do Grupo 5- Corretivos orgânicos, Classe II podendo ser utilizado em agricultura. Os resultados obtidos nos ensaios permitem concluir que o composto não apresentou efeitos de fitotoxicidade sobre a germinação das sementes e apresentou um efeito positivo no teor de matéria orgânica do solo, possuindo assim características de matéria fertilizante como corretivo orgânico. A produção da cultura, quer de matéria verde quer de matéria seca, foi semelhante entre as modalidades com aplicação de composto e com adubação mineral. A utilização de composto apesar de não veicular quantidades significativas de P revela ter um efeito positivo na fitodisponibilidade em fósforo do solo. Da aplicação do composto não resultou uma acumulação de micronutrientes e metais pesados (Cu, Zn, Mn, Pb, Cd, Cr e Ni), quer no solo quer nas plantas. Este ensaio demonstrou, que a dose 10 t ha-1 de composto complementado com cerca de 50 kg de azoto mineral permitiu ultrapassar os efeitos negativos da imobilização de azoto, e simultaneamente demonstrou um efeito positivo quer no teor de matéria orgânica do solo, quer na
disponibilização de N e P originando uma mais adequada nutrição da cultura. Esta modalidade conduziu a uma poupança de 68% na utilização exclusiva de azoto mineral.info:eu-repo/semantics/publishedVersio
Distribution of hepatitis C virus genotypes among blood donors from mid-west region of Brazil
In order to investigate the hepatitis C virus (HCV) genotypes in mid-west region of Brazil, 250 anti-HCV positive blood donors were studied. Among them, the anti-HCV serological status was confirmed in 205 (82%). HCV RNA was detected in 165 samples, which were genotyped. HCV types 1, 2 and 3 were found in 67.9%, 3% and 29.1% of the donors, respectively. In Goiás state, subtype 1a (50%) was the most prevalent, followed by subtypes 3a (30.9%) and 1b (16.7%). In Mato Grosso state, subtype 1a was also predominant (41%), followed by subtypes 1b (29.5%) and 3a (25%). In Mato Grosso do Sul state, subtypes 1a and 1b were detected equally (36.8%), followed by 3a (21.1%). Subtype 2b was rare (2.4%, 4.5% and 5.3%, respectively). In Distrito Federal, subtype 3a (39%) was more frequent than 1a (31.7%) and the remaining (29.3%) belonged to subtype 1b.Com objetivo de determinar os genótipos do vírus da hepatite C (HCV) circulantes na Região Centro-Oeste do Brasil, 250 doadores de sangue anti-HCV positivos foram estudados. Dentre eles, a positividade para anti-HCV foi confirmada em 205 (82%). O RNA-HCV foi detectado em 165 amostras, as quais foram genotipadas. Os tipos 1, 2 e 3 do HCV foram encontrados em 67,9%, 3% e 29,1% dos doadores, respectivamente. No Estado de Goiás, o subtipo 1a (50%) foi o mais prevalente, seguido pelos subtipos 3a (30,9%) e 1b (16,7%). No Estado de Mato Grosso, o subtipo 1a (41%) foi também predominante, seguido pelos subtipos 1b (29,5%) e 3a (25%). No Estado de Mato Grosso do Sul, os subtipos 1a e 1b foram igualmente detectados (36,8%), seguidos por 3a (21,1%). O subtipo 2b foi raro (2,4%, 4,5% e 5,3%, respectivamente). No Distrito Federal, o subtipo 3a (39%) foi mais freqüente que 1a (31,7%), sendo o restante (29,3%) identificado como subtipo 1b
Tuning the bioactivity of tensioactive deoxy glycosides to structure: antibacterial activity versus selective cholinesterase inhibition rationalized by molecular docking
New octyl/dodecyl 2,6-dideoxy-D-arabino-hexopyranosides
have been synthesized by a simple but efficient methodology
based on the reaction of glycals with alcohols catalysed by
triphenylphosphane hydrobromide, deprotection, regioselective tosylation and reduction. Their surface-active properties
were evaluated in terms of adsorption and aggregation parameters and compared with those of 2-deoxy-D-glycosides
and 2,6-dideoxy-L-glycosides. Deoxygenation at the 6-position led to a decrease in the critical micelle concentration,
and an increase in the adsorption efficiency (pC20) promoting
aggregation more efficiently than adsorption. With regard to
the antibacterial activity, dodecyl 2,6-dideoxy-α-L-arabino-hexopyranoside was the most active compound towards Bacillus anthracis (MIC 25 μM), whereas its enantiomer exhibited a MIC value of 50 μM. Both 2,6-dideoxy glycosides were
active towards Bacillus cereus, Bacillus subtilis, Enterococcus
faecalis and Listeria monocytogenes. In contrast, none of the
2-deoxy glycosides was significantly active. These results
and the data on surface activity suggest that aggregation is
a key issue for antimicrobial activity. Beyond infection, Alzheimer’s disease also threatens elderly populations. In the search for butyrylcholinesterase (BChE) selective inhibition, 2-
deoxy glycosides were screened in vitro by using Ellman’s
assay. Octyl 2-deoxy-α-D-glycoside was found to be a BChE
selective inhibitor promoting competitive inhibition. Docking
studies supported these results as they pinpoint the importance of the primary OH group in stabilizing the BChE inhibitor complex. A size-exclusion mechanism for inhibition has
been proposed based on the fact that acetylcholinesterase
(AChE) exhibits several bulky residues that hinder access to
the active-site cavity. This work shows how the deoxygenation pattern, configuration and functionality of the anomeric
centre can tune physical and surface properties as well as
the bioactivity of these multifunctional and stereochemically
rich molecules.FEDER e FCTinfo:eu-repo/semantics/publishedVersio
Have the cake and eat it: optimizing nondestructive DNA metabarcoding of macroinvertebrate samples for freshwater biomonitoring
Resource ArticleDNA metabarcoding can contribute to improving cost‐effectiveness and accuracy of
biological assessments of aquatic ecosystems, but significant optimization and standardization
efforts are still required to mainstream its application into biomonitoring
programmes. In assessments based on freshwater macroinvertebrates, a key challenge
is that DNA is often extracted from cleaned, sorted and homogenized bulk
samples, which is time‐consuming and may be incompatible with sample preservation
requirements of regulatory agencies. Here, we optimize and evaluate metabarcoding
procedures based on DNA recovered from 96% ethanol used to preserve field
samples and thus including potential PCR inhibitors and nontarget organisms. We
sampled macroinvertebrates at five sites and subsampled the preservative ethanol at
1 to 14 days thereafter. DNA was extracted using column‐based enzymatic (TISSUE)
or mechanic (SOIL) protocols, or with a new magnetic‐based enzymatic protocol
(BEAD), and a 313‐bp COI fragment was amplified. Metabarcoding detected at least
200 macroinvertebrate taxa, including most taxa detected through morphology and
for which there was a reference barcode. Better results were obtained with BEAD
than SOIL or TISSUE, and with subsamples taken 7–14 than 1–7 days after sampling,
in terms of DNA concentration and integrity, taxa diversity and matching between
metabarcoding and morphology. Most variation in community composition was explained
by differences among sites, with small but significant contributions of subsampling
day and extraction method, and negligible contributions of extraction and
PCR replication. Our methods enhance reliability of preservative ethanol as a potential
source of DNA for macroinvertebrate metabarcoding, with a strong potential application
in freshwater biomonitoringinfo:eu-repo/semantics/publishedVersio
Arbuscular Mycorrhiza Extraradical Mycelium Promotes Si and Mn Subcellular Redistribution in Wheat Grown under Mn Toxicity
Abstract: Manganese (Mn) and aluminum (Al) toxicities are serious edaphic limitations to crop
production in acidic soils. Excess Mn can be countered using a stress-adapted soil microbiota that
establish symbiotic relationships with native plants. The arbuscular mycorrhizal fungi (AMF) associated with Lolium rigidum L. develop extraradical mycelia (ERM) that quickly colonize wheat and
lead to greater shoot growth by promoting stress-evading mechanisms that are not yet completely explained. In the present study, wheat growth was assessed after 3 weeks on disturbed and undisturbed
(intact ERM) acidic soil where the native non-mycotrophic Silene gallica L. or strongly mycotrophic
L. rigidum were previously developed. The physiological and biochemical mechanisms responsible for increased growth were analyzed by assessing wheat leaf chlorophyll content, photosystem
II quantum yield and performance index, enzymatic activity of ascorbate peroxidase (APX), catalase
(CAT), glutathione reductase (GR), guaiacol peroxidase (GPX), superoxide dismutase (SOD) and
contents and subcellular localization of Mn, Mg, Si and K. The soil from native plants had a beneficial
effect on shoot weight and chlorophyll levels. The highest benefits were obtained for wheat grown in
soil with intact ERM associated with L. rigidum. In this condition, where earlier mycorrhization was
favored, the Mn content decreased, alongside the content of Si, while the Mg/Mn ratio increased. Mn
was redirected to the apoplast, while Si was redirected to the symplast. The activity of APX, GPX and
SOD increased, probably due to increased metabolic growth (higher shoot weight and chlorophyll
content). Understanding the mechanisms induced by native AMF responsible for increasing wheat
performance can contribute to the establishment of sustainable approaches for crop production in
acidic soils with Mn toxicity. The use of native plant AMF developers can improve the sustainable
use of natural resources in the scope of greener agricultural practice
Transnational cooperation in enhancing researchers’ wider employability: the TRANSPEER project
The purpose of this paper is to provide an example of best practice towards enhancing employability in the cross-sectoral labour market for doctorate-holders. This was achieved through an Erasmus+ KA2 (Strategic Partnership) skills development project which created a training programme (TRANSPEER) involving a multi-disciplinary cohort of researchers at a range of career stages, drawn from universities in Norway, Portugal, Sweden and the UK.info:eu-repo/semantics/publishedVersio
DRY BEAN CULTIVAR IAC ALVORADA UNDER DIFFERENT RATES OF \u3ci\u3eRHIZOBIUM\u3c/i\u3e INOCULANT IN THE PLANTING FURROW
INTRODUCTION: No publications were found regarding liquid inoculation in the planting furrow of dry bean, which indicates a demand for investigations to assist the producer in deciding which method of inoculation to adopt. Thus, the aim of this study was to evaluate the viability of liquid inoculation in the planting furrow and determine the best application rate of inoculant, using the dry bean cultivar IAC Alvorada.
MATERIALS AND METHODS: A field experiment was conducted in a no-till planting system in the 2014/2015 crop season in a Latossolo Vermelho distrófico in the municipality of Lambari, MG, Brazil. The experimental design was randomized blocks with three replications and eight treatments, involving five application rates of liquid inoculant in the planting furrow (0, 120, 240, 480, and 720 mL ha-1), liquid seed inoculation (40 mL kg-1), and two controls without inoculation: one with N-urea (80 kg ha-1 N, ½ at sowing and ½ in topdressing, between the V3 and V4 stages of the crop cycle) and another without mineral N.
The experimental unit (14.4 m2) consisted of six four-meter-length rows, spaced at 0.6 m, and the area effectively used was the four central rows. All the plots received base fertilization of 110 kg ha-1 of P2O5 (simple superphosphate) and 40 kg ha-1 of K2O (potassium chloride), mechanically applied during furrowing. In addition, all levels of inoculation received 20 kg Nurea ha-1, so as to meet the recommendations of Soares et al. (2016). Sowing was manual at the density of 15 seeds per meter and the cultivar used was IAC Alvorada, of semi-upright plant architecture and moderate resistance to anthracnose (Carbonell et al., 2008)
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