Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 317
Filtrar
Más filtros

Intervalo de año de publicación
1.
Nature ; 592(7853): 283-289, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33524990

RESUMEN

A safe and effective vaccine against COVID-19 is urgently needed in quantities that are sufficient to immunize large populations. Here we report the preclinical development of two vaccine candidates (BNT162b1 and BNT162b2) that contain nucleoside-modified messenger RNA that encodes immunogens derived from the spike glycoprotein (S) of SARS-CoV-2, formulated in lipid nanoparticles. BNT162b1 encodes a soluble, secreted trimerized receptor-binding domain (known as the RBD-foldon). BNT162b2 encodes the full-length transmembrane S glycoprotein, locked in its prefusion conformation by the substitution of two residues with proline (S(K986P/V987P); hereafter, S(P2) (also known as P2 S)). The flexibly tethered RBDs of the RBD-foldon bind to human ACE2 with high avidity. Approximately 20% of the S(P2) trimers are in the two-RBD 'down', one-RBD 'up' state. In mice, one intramuscular dose of either candidate vaccine elicits a dose-dependent antibody response with high virus-entry inhibition titres and strong T-helper-1 CD4+ and IFNγ+CD8+ T cell responses. Prime-boost vaccination of rhesus macaques (Macaca mulatta) with the BNT162b candidates elicits SARS-CoV-2-neutralizing geometric mean titres that are 8.2-18.2× that of a panel of SARS-CoV-2-convalescent human sera. The vaccine candidates protect macaques against challenge with SARS-CoV-2; in particular, BNT162b2 protects the lower respiratory tract against the presence of viral RNA and shows no evidence of disease enhancement. Both candidates are being evaluated in phase I trials in Germany and the USA1-3, and BNT162b2 is being evaluated in an ongoing global phase II/III trial (NCT04380701 and NCT04368728).


Asunto(s)
Vacunas contra la COVID-19/inmunología , COVID-19/inmunología , COVID-19/prevención & control , Modelos Animales de Enfermedad , SARS-CoV-2/inmunología , Envejecimiento/inmunología , Animales , Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/inmunología , Antígenos Virales/química , Antígenos Virales/genética , Antígenos Virales/inmunología , Vacuna BNT162 , COVID-19/sangre , COVID-19/terapia , COVID-19/virología , Vacunas contra la COVID-19/administración & dosificación , Vacunas contra la COVID-19/química , Vacunas contra la COVID-19/genética , Línea Celular , Ensayos Clínicos como Asunto , Femenino , Humanos , Inmunización Pasiva , Internacionalidad , Macaca mulatta/inmunología , Macaca mulatta/virología , Masculino , Ratones , Ratones Endogámicos BALB C , Modelos Moleculares , Multimerización de Proteína , ARN Viral/análisis , Sistema Respiratorio/inmunología , Sistema Respiratorio/virología , SARS-CoV-2/química , SARS-CoV-2/genética , Solubilidad , Glicoproteína de la Espiga del Coronavirus/química , Glicoproteína de la Espiga del Coronavirus/genética , Glicoproteína de la Espiga del Coronavirus/inmunología , Linfocitos T/inmunología , Vacunación , Vacunas Sintéticas/administración & dosificación , Vacunas Sintéticas/química , Vacunas Sintéticas/genética , Vacunas Sintéticas/inmunología , Sueroterapia para COVID-19 , Vacunas de ARNm
2.
Arch Microbiol ; 206(7): 328, 2024 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-38935150

RESUMEN

Marine hydrocarbonoclastic bacteria can use polycyclic aromatic hydrocarbons as carbon and energy sources, that makes these bacteria highly attractive for bioremediation in oil-polluted waters. However, genomic and metabolic differences between species are still the subject of study to understand the evolution and strategies to degrade PAHs. This study presents Rhodococcus ruber MSA14, an isolated bacterium from marine sediments in Baja California, Mexico, which exhibits adaptability to saline environments, a high level of intrinsic pyrene tolerance (> 5 g L- 1), and efficient degradation of pyrene (0.2 g L- 1) by 30% in 27 days. Additionally, this strain demonstrates versatility by using naphthalene and phenanthrene as individual carbon sources. The genome sequencing of R. ruber MSA14 revealed a genome spanning 5.45 Mbp, a plasmid of 72 kbp, and three putative megaplasmids, lengths between 110 and 470 Kbp. The bioinformatics analysis of the R. ruber MSA14 genome revealed 56 genes that encode enzymes involved in the peripheral and central pathways of aromatic hydrocarbon catabolism, alkane, alkene, and polymer degradation. Within its genome, R. ruber MSA14 possesses genes responsible for salt tolerance and siderophore production. In addition, the genomic analysis of R. ruber MSA14 against 13 reference genomes revealed that all compared strains have at least one gene involved in the alkanes and catechol degradation pathway. Overall, physiological assays and genomic analysis suggest that R. ruber MSA14 is a new haloalkalitolerant and hydrocarbonoclastic strain toward a wide range of hydrocarbons, making it a promising candidate for in-depth characterization studies and bioremediation processes as part of a synthetic microbial consortium, as well as having a better understanding of the catabolic potential and functional diversity among the Rhodococci group.


Asunto(s)
Biodegradación Ambiental , Genoma Bacteriano , Genómica , Sedimentos Geológicos , Hidrocarburos Policíclicos Aromáticos , Rhodococcus , Rhodococcus/genética , Rhodococcus/metabolismo , Hidrocarburos Policíclicos Aromáticos/metabolismo , Sedimentos Geológicos/microbiología , Naftalenos/metabolismo , Filogenia , Fenantrenos/metabolismo , Tolerancia a la Sal , Pirenos
3.
Molecules ; 29(2)2024 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-38257303

RESUMEN

We present a study on the green synthesis of undoped and Er-doped ZnO compounds using Mangifera indica gum (MI). A set of tests were conducted to assess the structure of the material. The tests included X-ray diffraction, Raman, and Fourier-transform infrared spectroscopy. Optical properties were studied using diffuse reflectance and photoluminescence. Morphological and textural investigations were done using SEM images and N2 adsorption/desorption. Furthermore, photocatalytic tests were performed with methylene blue (MB), yellow eosin (EY), and the pharmaceutical drug ibuprofen (IBU) under UV irradiation. The study demonstrated that replacing the stabilizing agent with Mangifera indica gum is an effective method for obtaining ZnO nanoparticles. Additionally, the energy gap of the nanoparticles exhibits a slight reduction in value. Photoluminescence studies showed the presence of zinc vacancies and other defects in both samples. In the photocatalytic test, the sample containing Er3+ exhibited a degradation of 99.7% for methylene blue, 81.2% for yellow eosin, and 52.3% for ibuprofen over 120 min. In the presence of methyl alcohol, the degradation of MB and EY dyes is 16.7% and 55.7%, respectively. This suggests that hydroxyl radicals are responsible for the direct degradation of both dyes. In addition, after the second reuse, the degradation rate for MB was 94.08%, and for EY, it was 82.35%. For the third reuse, the degradation rate for MB was 97.15%, and for EY, it was 17%. These results indicate the significant potential of the new semiconductor in environmental remediation applications from an ecological synthesis.


Asunto(s)
Mangifera , Nanopartículas , Óxido de Zinc , Eosina Amarillenta-(YS) , Azul de Metileno , Fotólisis , Ibuprofeno , Colorantes
4.
Geriatr Nurs ; 55: 362-367, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38171187

RESUMEN

The objective of this research was to analyze the risk of adverse effects in patients older than 65 years with dementia and in concomitant treatment with antidementia and antipsychotic drugs and who are cared for by community nurses. A retrospective cross-sectional descriptive study was carried out. A total of 332 patients who were cared for by primary care teams participated. Most of the patients were women, totally dependent for the basic activities of daily living and residing in the family home. They were polymedicated and there was poor therapeutic adherence. The risk of adverse effects was higher in polymedicated patients who had been taking antipsychotics for longer periods and in those who had a main caregiver. However, those patients who had been assessed by the community nurse were protected from suffering adverse effects. This study demonstrates how integrated and continuous nursing care can reduce adverse effects in this type of patient.


Asunto(s)
Antipsicóticos , Demencia , Humanos , Femenino , Anciano , Masculino , Antipsicóticos/efectos adversos , Vida Independiente , Estudios Transversales , Estudios Retrospectivos , Actividades Cotidianas
5.
Arch Virol ; 168(3): 88, 2023 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-36786950

RESUMEN

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) lineage C.37 (Lambda) has spread rapidly in Peru and other Latin American countries. However, most studies in Peru have focused on Lima, the capital city, without knowing the dynamics of the spread of the variant in other departments. Cusco, Peru, is one of the most popular departments in the country for tourists, so the introduction of new variants of SARS-CoV-2 might occur despite closure of the borders. Therefore, in this work, we analyzed the variants circulating in Cusco. The aim of this work was to better understand the distribution of SARS-CoV-2 lineages circulating in Cusco and to characterize the genomes of these strains. To this end, 46 SARS-CoV-2 genomes from vaccinated and unvaccinated patients were sequenced in the first half of 2021. The genomes were analyzed using phylogenetic and natural selection methods. Phylogenetic trees from Cusco showed dominance of the Lambda lineage over the variants of concern (VOCs), and there was no clustering of variants by district. Natural selection analysis revealed mutations, mainly in the spike protein, at positions 75, 246, 247, 707, 769, and 1020. In addition, we found that unvaccinated patients accumulated more new mutations than did vaccinated patients, and these included the F101Y mutation in ORF7a, E419A in NSP3, a deletion in S (21,618-22,501), and a deletion in ORF3a (25,437-26,122).


Asunto(s)
COVID-19 , SARS-CoV-2 , Selección Genética , Humanos , COVID-19/epidemiología , COVID-19/virología , Mutación , Perú/epidemiología , Filogenia , SARS-CoV-2/genética , Glicoproteína de la Espiga del Coronavirus/genética
6.
Cultur Divers Ethnic Minor Psychol ; 29(3): 332-338, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35446063

RESUMEN

OBJECTIVES: This study provides further validity for scores produced by the Race-Based Traumatic Stress Symptom Scale (RBTSSS), through examining the relationship between perceived discrimination, trauma symptoms, and mental health symptoms with the RBTSSS. METHOD: Participants consisted of 148 people of color (54% women) with an average age of 33.38 years. Study hypotheses were tested using correlational and regression analyses. RESULTS: Validity was supported by strong relations with established symptom scores and perceived discrimination. Regression analysis found RBTSSS to be a significant predictor of trauma symptoms, controlling for general stress. Finally, multivariate analysis found perceived discrimination to be a stronger predictor of RBTSSS symptoms than general stress. CONCLUSIONS: The RBTSSS demonstrates strong relations with other symptom measures and perceived discrimination, supporting the validity of the RBTSSS scores. Both researchers and practitioners may benefit from use of the instrument which captures emotional outcomes specific to racial trauma. (PsycInfo Database Record (c) 2023 APA, all rights reserved).


Asunto(s)
Racismo , Humanos , Femenino , Adulto , Masculino , Racismo/psicología , Análisis de Regresión , Emociones
7.
Biom J ; 65(2): e2200035, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36136044

RESUMEN

Web surveys have replaced Face-to-Face and computer assisted telephone interviewing (CATI) as the main mode of data collection in most countries. This trend was reinforced as a consequence of COVID-19 pandemic-related restrictions. However, this mode still faces significant limitations in obtaining probability-based samples of the general population. For this reason, most web surveys rely on nonprobability survey designs. Whereas probability-based designs continue to be the gold standard in survey sampling, nonprobability web surveys may still prove useful in some situations. For instance, when small subpopulations are the group under study and probability sampling is unlikely to meet sample size requirements, complementing a small probability sample with a larger nonprobability one may improve the efficiency of the estimates. Nonprobability samples may also be designed as a mean for compensating for known biases in probability-based web survey samples by purposely targeting respondent profiles that tend to be underrepresented in these surveys. This is the case in the Survey on the impact of the COVID-19 pandemic in Spain (ESPACOV) that motivates this paper. In this paper, we propose a methodology for combining probability and nonprobability web-based survey samples with the help of machine-learning techniques. We then assess the efficiency of the resulting estimates by comparing them with other strategies that have been used before. Our simulation study and the application of the proposed estimation method to the second wave of the ESPACOV Survey allow us to conclude that this is the best option for reducing the biases observed in our data.


Asunto(s)
COVID-19 , Humanos , COVID-19/epidemiología , España/epidemiología , Pandemias , Encuestas y Cuestionarios , Probabilidad , Aprendizaje Automático
8.
Molecules ; 28(23)2023 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-38067502

RESUMEN

This work adopted a green synthesis route using cashew tree gum as a mediating agent to obtain Ni-doped ZnO nanoparticles through the sol-gel method. Structural analysis confirmed the formation of the hexagonal wurtzite phase and distortions in the crystal lattice due to the inclusion of Ni cations, which increased the average crystallite size from 61.9 nm to 81.6 nm. These distortions resulted in the growth of point defects in the structure, which influenced the samples' optical properties, causing slight reductions in the band gaps and significant increases in the Urbach energy. The fitting of the photoluminescence spectra confirmed an increase in the concentration of zinc vacancy defects (VZn) and monovacancies (Vo) as Zn cations were replaced by Ni cations in the ZnO structure. The percentage of VZn defects for the pure compound was 11%, increasing to 40% and 47% for the samples doped with 1% and 3% of Ni cations, respectively. In contrast, the highest percentage of VO defects is recorded for the material with the lowest Ni ions concentration, comprising about 60%. The influence of dopant concentration was also reflected in the photocatalytic performance. Among the samples tested, the Zn0.99Ni0.01O compound presented the best result in MB degradation, reaching an efficiency of 98.4%. Thus, the recovered material underwent reuse tests, revealing an efficiency of 98.2% in dye degradation, confirming the stability of the photocatalyst. Furthermore, the use of different inhibitors indicated that •OH radicals are the main ones involved in removing the pollutant. This work is valuable because it presents an ecological synthesis using cashew gum, a natural polysaccharide that has been little explored in the literature.

9.
Br J Clin Pharmacol ; 88(5): 2359-2371, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-34904270

RESUMEN

AIMS: To identify linzagolix doses, an oral GnRH receptor antagonist, that effectively lower oestradiol (E2) to relieve endometriosis-related pelvic pain without compromising bone health. METHODS: Integrated statistical, pharmacokinetic-pharmacodynamic and systems pharmacology models were developed from Phase 1 and 2 clinical trial data in healthy volunteers and patients, receiving linzagolix 25-200 mg daily or placebo, and analysed simultaneously. The main outcome measures were pelvic pain scores for dysmenorrhoea, nonmenstrual pelvic pain (NMPP), uterine bleeding and lumbar spine bone mineral density (BMD). RESULTS: Linzagolix pharmacokinetics were described by a 2-compartment model with sequential zero/first-order absorption process (CL/F: 0.422 L/h). E2 changes over time were well described as a function of linzagolix 24-hour AUC (AUC50 : 1.68 × 105 ng h/mL). For a Caucasian reference patient, a change in E2 from 50-20 pg/mL at 24 weeks increased the odds of relief of dysmenorrhoea 1.33-fold and NMPP 1.07-fold (95% CI: 1.22-1.47 and 1.02-1.12, respectively) and decreased bleeding days by 1.55 (95% CI: 1.39-1.72). A previously validated quantitative systems pharmacology BMD model was adjusted to the clinical data. The mean week 24 lumbar spine BMD change from baseline ranged from -0.092% in the 50 mg dose, -1.30% in the 100 mg dose group and -2.67% in the 200 mg dose group. DISCUSSION: The previously-reported E2 target range (20-50 pg/mL) to balance efficacy and safety endpoints was confirmed. Linzagolix once daily doses between 75-125 mg daily were expected to meet endometriosis-associated pain, efficacy, and BMD loss targets in Caucasian patients.


Asunto(s)
Endometriosis , Receptores LHRH , Densidad Ósea , Ácidos Carboxílicos , Dismenorrea/tratamiento farmacológico , Endometriosis/tratamiento farmacológico , Femenino , Antagonistas de Hormonas/farmacología , Antagonistas de Hormonas/uso terapéutico , Humanos , Dolor Pélvico/tratamiento farmacológico , Pirimidinas , Receptores LHRH/uso terapéutico
10.
BMC Health Serv Res ; 22(1): 649, 2022 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-35568892

RESUMEN

BACKGROUND: Collaborative practice between community pharmacists and physicians is becoming increasingly common. Although tools and models to explore collaborative practice between both health care professionals have been developed, very few have been validated for their use in clinical practice. The objective of this study was to develop and validate a tool for measuring collaborative practice between community pharmacists and physicians from the perspective of community pharmacists. METHODS: The DeVellis method was used to develop and validate the Professional Collaborative Practice Tool. A pool of 40 items with Likert frequency scales was generated based on previous literature and expert opinion. This study was undertaken in Spain. A sample of community pharmacists providing medication reviews with follow-up and a random sample of pharmacists providing usual care were invited to participate. Exploratory and confirmatory factor analysis was used to assess the tool's reliability and content validity. RESULTS: Three hundred thirty-six pharmacists were invited with an overall response rate of 84.8%. The initial 40 items selected were reduced to 14 items. Exploratory Factor Analysis provided a 3-factor solution explaining 62% of the variance. Confirmatory Factor Analysis confirmed the three factors "Activation for collaborative professional practice," the "Integration in collaborative professional practice," and the "Professional acceptance in collaborative professional practice." The tool demonstrated an adequate fit (X2/df = 1.657, GFI = 0.889 and RMSEA = 0.069) and good internal consistency (Cronbach's alpha = 0.924). CONCLUSIONS: The Professional Collaborative Practice Tool has shown good internal reliability and criterion validity. The tool could be used to measure the perceived level of collaborative practice between community pharmacists and physicians and monitor changes over time. Its applicability and transferability to other settings should be evaluated.


Asunto(s)
Farmacéuticos , Médicos , Actitud del Personal de Salud , Conducta Cooperativa , Humanos , Práctica Profesional , Reproducibilidad de los Resultados , Encuestas y Cuestionarios
11.
Plant Mol Biol ; 107(4-5): 365-385, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33521880

RESUMEN

KEY MESSAGE: Evolutionary conserved defense mechanisms present in extant bryophytes and angiosperms, as well as moss-specific defenses are part of the immune response of Physcomitrium patens. Bryophytes and tracheophytes are descendants of early land plants that evolved adaptation mechanisms to cope with different kinds of terrestrial stresses, including drought, variations in temperature and UV radiation, as well as defense mechanisms against microorganisms present in the air and soil. Although great advances have been made on pathogen perception and subsequent defense activation in angiosperms, limited information is available in bryophytes. In this study, a transcriptomic approach uncovered the molecular mechanisms underlying the defense response of the bryophyte Physcomitrium patens (previously Physcomitrella patens) against the important plant pathogen Botrytis cinerea. A total of 3.072 differentially expressed genes were significantly affected during B. cinerea infection, including genes encoding proteins with known functions in angiosperm immunity and involved in pathogen perception, signaling, transcription, hormonal signaling, metabolic pathways such as shikimate and phenylpropanoid, and proteins with diverse role in defense against biotic stress. Similarly as in other plants, B. cinerea infection leads to downregulation of genes involved in photosynthesis and cell cycle progression. These results highlight the existence of evolutionary conserved defense responses to pathogens throughout the green plant lineage, suggesting that they were probably present in the common ancestors of land plants. Moreover, several genes acquired by horizontal transfer from prokaryotes and fungi, and a high number of P. patens-specific orphan genes were differentially expressed during B. cinerea infection, suggesting that they are important players in the moss immune response.


Asunto(s)
Bryopsida/genética , Resistencia a la Enfermedad/genética , Perfilación de la Expresión Génica/métodos , Regulación de la Expresión Génica de las Plantas , Enfermedades de las Plantas/genética , Plantas/genética , Botrytis/fisiología , Bryopsida/microbiología , Ontología de Genes , Interacciones Huésped-Patógeno , Redes y Vías Metabólicas/genética , Enfermedades de las Plantas/microbiología , Proteínas de Plantas/genética , Plantas/clasificación , Plantas/microbiología , RNA-Seq/métodos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Especificidad de la Especie
12.
Environ Microbiol ; 23(7): 3435-3459, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-32666586

RESUMEN

Polycyclic aromatic hydrocarbons (PAHs) are among the most persistent xenobiotic compounds, with high toxicity effects. Mycoremediation with halophilic Aspergillus sydowii was used for their removal from a hypersaline medium (1 M NaCl). A. sydowii metabolized PAHs as sole carbon sources, resulting in the removal of up to 90% for both PAHs [benzo [a] pyrene (BaP) and phenanthrene (Phe)] after 10 days. Elimination of Phe and BaP was almost exclusively due to biotransformation and not adsorption by dead mycelium and did not correlate with the activity of lignin modifying enzymes (LME). Transcriptomes of A. sydowii grown on PAHs, or on glucose as control, both at hypersaline conditions, revealed 170 upregulated and 76 downregulated genes. Upregulated genes were related to starvation, cell wall remodelling, degradation and metabolism of xenobiotics, DNA/RNA metabolism, energy generation, signalling and general stress responses. Changes of LME expression levels were not detected, while the chloroperoxidase gene, possibly related to detoxification processes in fungi, was strongly upregulated. We propose that two parallel metabolic pathways (mitochondrial and cytosolic) are involved in degradation and detoxification of PAHs in A. sydowii resulting in intracellular oxidation of PAHs. To the best of our knowledge, this is the most comprehensive transcriptomic analysis on fungal degradation of PAHs.


Asunto(s)
Hidrocarburos Policíclicos Aromáticos , Transcriptoma , Aspergillus/genética , Biodegradación Ambiental , Perfilación de la Expresión Génica , Transcriptoma/genética
13.
Molecules ; 26(5)2021 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-33652788

RESUMEN

Molybdates are biocidal materials that can be useful in coating surfaces that are susceptible to contamination and the spread of microorganisms. The aim of this work was to investigate the effects of copper doping of hydrated cobalt molybdate, synthesized by the co-precipitation method, on its antibacterial activity and to elucidate the structural and morphological changes caused by the dopant in the material. The synthesized materials were characterized by PXRD, Fourier Transformed Infrared (FTIR), thermogravimetric analysis/differential scanning calorimetry (TG/DSC), and SEM-Energy Dispersive Spectroscopy (SEM-EDS). The antibacterial response of the materials was verified using the Minimum Inhibitory Concentration (MIC) employing the broth microdilution method. The size of the CoMoO4·1.03H2O microparticles gradually increased as the percentage of copper increased, decreasing the energy that is needed to promote the transition from the hydrated to the beta phase and changing the color of material. CoMoO4·1.03H2O obtained better bactericidal performance against the tested strains of Staphylococcus aureus (gram-positive) than Escherichia coli (gram-negative). However, an interesting point was that the use of copper as a doping agent for hydrated cobalt molybdate caused an increase of MIC value in the presence of E. coli and S. aureus strains. The study demonstrates the need for caution in the use of copper as a doping material in biocidal matrices, such as cobalt molybdate.


Asunto(s)
Antiinfecciosos/química , Cobalto/química , Cobre/química , Molibdeno/química , Antiinfecciosos/farmacología , Infecciones Bacterianas/tratamiento farmacológico , Complejos de Coordinación/química , Escherichia coli/efectos de los fármacos , Humanos , Nanopartículas del Metal/química , Pruebas de Sensibilidad Microbiana , Tamaño de la Partícula , Staphylococcus aureus/efectos de los fármacos
14.
Appl Microbiol Biotechnol ; 104(19): 8243-8256, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32803297

RESUMEN

Cold-adapted (CA) microorganisms (= psychrophiles or psychrotolerants) are key players of many ecological interactions in natural ecosystems. Some of them can colonize the rhizosphere of plants and cause damage to their hosts; others, on the contrary, protect plants from their pathogens through direct and indirect mechanisms, thus promoting plant growth and development. These "protective" microbes are known as biocontrol agents (BCA). BCA either limit or inhibit the growth of plant pathogens, owing to the excretion of a panoply of secondary metabolites (including soluble and volatile antibiotics, siderophores, quorum sensing interfering agents). BCA can also control plant pathogens through indirect mechanisms, including competence for nutrients and space, or else by interfering with their chemical communication. That explains why some of these BCA have been included in the formulation of commercial biopesticides, which are environmentally friendly products containing live cells used to control plant diseases and pests. At present, the development of biopesticides from mesophilic microorganisms is an established technology. Unfortunately, these biopesticides are not active at low temperatures. On the other hand, the information concerning the potential use of CA-BCA for the same goal is at its infancy. Here, we review the current knowledge concerning the isolation, identification, and characterization of CA microbes which act as antagonists of plant pathogens, including the mechanisms they deploy to antagonize plant pathogens. We also illustrate their biotechnological potential to develop CA biopesticides and discuss their utility in the context of mountainous agriculture. KEY POINTS: • Many naturally occurring cold-active microbes antagonize plant pathogens. • The mechanisms of biocontrol exerted by these microbes are either direct or indirect. • Cold-active biocontrol agents can be used to develop biopesticides. • Cold-active biopesticides are crucial for sustainably intensifying agriculture in cold climates.


Asunto(s)
Agentes de Control Biológico , Clima Frío , Agricultura , Ecosistema , Desarrollo de la Planta , Plantas
15.
Proteins ; 85(7): 1222-1237, 2017 07.
Artículo en Inglés | MEDLINE | ID: mdl-28276654

RESUMEN

Activated sludge is produced during the treatment of sewage and industrial wastewaters. Its diverse chemical composition allows growth of a large collection of microbial phylotypes with very different physiologic and metabolic profiles. Thus, activated sludge is considered as an excellent environment to discover novel enzymes through functional metagenomics, especially activities related with degradation of environmental pollutants. Metagenomic DNA was isolated and purified from an activated sludge sample. Metagenomic libraries were subsequently constructed in Escherichia coli. Using tributyrin hydrolysis, a screening by functional analysis was conducted and a clone that showed esterase activity was isolated. Blastx analysis of the sequence of the cloned DNA revealed, among others, an ORF that encodes a putative thioesterase with 47-64% identity to GenBank CDS reported genes, similar to those in the hotdog fold thioesterase superfamily. On the basis of its amino acid similarity and its homology-modelled structure we deduced that this gene encodes an enzyme (ThYest_ar) that belongs to family TE13, with a preference for aryl-CoA substrates and a novel catalytic residue constellation. Plasmid retransformation in E. coli confirmed the clone's phenotype, and functional complementation of a paaI E. coli mutant showed preference for phenylacetate over chlorobenzene as a carbon source. This work suggests a role for TE13 family thioesterases in swimming and degradation approaches for phenyl acetic acid. Proteins 2017; 85:1222-1237. © 2017 Wiley Periodicals, Inc.


Asunto(s)
Metagenoma , Fenilacetatos/química , Aguas del Alcantarillado/microbiología , Tioléster Hidrolasas/genética , Secuencia de Aminoácidos , Biodegradación Ambiental , Clorobencenos/química , Clorobencenos/metabolismo , Clonación Molecular , Escherichia coli/genética , Escherichia coli/metabolismo , Expresión Génica , Biblioteca de Genes , Prueba de Complementación Genética , Humanos , Cinética , Metagenómica , Sistemas de Lectura Abierta , Fenilacetatos/metabolismo , Dominios y Motivos de Interacción de Proteínas , Estructura Secundaria de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Alineación de Secuencia , Homología Estructural de Proteína , Especificidad por Sustrato , Tioléster Hidrolasas/química , Tioléster Hidrolasas/metabolismo
16.
Eur Arch Otorhinolaryngol ; 274(5): 2175-2181, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28175991

RESUMEN

Spontaneous cerebrospinal fluid (CSF) leaks represent a clinical entity in which CSF rhinorrhea occurs in the absence of any inciting event. Spontaneous CSF leaks are associated with elevated intracranial pressure (ICP) or have underlying idiopathic intracranial hypertension (IIH). We report a cohort of patients who have undergone nasal endoscopic repair for spontaneous CSF leaks. We review our perioperative complications and the effectiveness of the nasal endoscopic approach to repair spontaneous CSF leaks. Also, we examine the evidence correlating spontaneous CSF leaks and IIH and the role of decreasing ICP in the treatment of nasal spontaneous CSF leaks. A retrospective analysis of patients with nasal spontaneous cerebrospinal fluid leaks was performed. Data on the nature of presentation, patient body mass index, defect location and size, ICP, clinical follow-up, and complications were collected. Thirty-five patients had nasal spontaneous cerebrospinal fluid leaks with evidence of IIH's symptoms. The most common sites were the cribriform plate, the ethmoid roof, and sphenoid lateral pterygoid recess. All patients underwent endonasal endoscopic surgery to repair the defect. Postoperatively, all patients underwent lumbar drainage and acetazolamide therapy. Nasal spontaneous cerebrospinal fluid leaks represent a surgical challenge because of their high recurrence rates. The most important factor for obtaining a successful repair in these patients is reducing their intracranial pressure through nutritional, medical, or surgical means.


Asunto(s)
Pérdida de Líquido Cefalorraquídeo/cirugía , Cirugía Endoscópica por Orificios Naturales/métodos , Seudotumor Cerebral/complicaciones , Pérdida de Líquido Cefalorraquídeo/diagnóstico por imagen , Pérdida de Líquido Cefalorraquídeo/etiología , Rinorrea de Líquido Cefalorraquídeo/etiología , Drenaje , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Nariz , Estudios Retrospectivos
17.
J Environ Manage ; 198(Pt 2): 1-11, 2017 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-28499155

RESUMEN

A number of fungal strains belonging to the ascomycota, basidiomycota and zygomycota genera were subjected to an in vitro screening regime to assess their ligninolytic activity potential, with a view to their potential use in mycoremediation-based strategies to remove phenolic compounds and polycyclic aromatic hydrocarbons (PAHs) from industrial wastewaters. All six basidiomycetes completely decolorized remazol brilliant blue R (RBBR), while also testing positive in both the guaiacol and gallic acid tests indicating good levels of lignolytic activity. All the fungi were capable of tolerating phenanthrene, benzo-α- pyrene, phenol and p-chlorophenol in agar medium at levels of 10 ppm. Six of the fungal strains, Pseudogymnoascus sp., Aspergillus caesiellus, Trametes hirsuta IBB 450, Phanerochate chrysosporium ATCC 787, Pleurotus ostreatus MTCC 1804 and Cadophora sp. produced both laccase and Mn peroxidase activity in the ranges of 200-560 U/L and 6-152 U/L, respectively, in liquid media under nitrogen limiting conditions. The levels of adsorption of the phenolic and PAHs were negligible with 99% biodegradation being observed in the case of benzo-α-pyrene, phenol and p-chlorophenol. The aforementioned six fungal strains were also found to be able to effectively treat highly alkaline industrial wastewater (pH 12.4). When this wastewater was supplemented with 0.1 mM glucose, all of the tested fungi, apart from A. caesiellus, displayed the capacity to remove both the phenolic and PAH compounds. Based on their biodegradative capacity we found T. hirsuta IBB 450 and Pseudogymnoascus sp., to have the greatest potential for further use in mycoremediation based strategies to treat wastestreams containing phenolics and PAHs.


Asunto(s)
Hidrocarburos Policíclicos Aromáticos/metabolismo , Purificación del Agua , Biodegradación Ambiental , Clorofenoles , Residuos Industriales , Fenoles , Trametes
18.
Appl Microbiol Biotechnol ; 100(8): 3637-54, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26782747

RESUMEN

In the present work, the local isolate Bacillus pumilus 15.1 has been morphologically and biochemically characterized in order to gain a better understanding of this novel entomopathogenic strain active against Ceratitis capitata. This strain could represent an interesting biothechnological tool for the control of this pest. Here, we report on its nutrient preferences, extracellular enzyme production, motility mechanism, biofilm production, antibiotic suceptibility, natural resistance to chemical and physical insults, and morphology of the vegetative cells and spores. The pathogen was found to be ß-hemolytic and susceptible to penicillin, ampicillin, chloramphenicol, gentamicin, kanamycin, rifampicin, tetracycline, and streptomycin. We also report a series of biocide, thermal, and UV treatments that reduce the viability of B. pumilus 15.1 by several orders of magnitude. Heat and chemical treatments kill at least 99.9 % of vegetative cells, but spores were much more resistant. Bleach was the only chemical that was able to completely eliminate B. pumilus 15.1 spores. Compared to the B. subtilis 168 spores, B. pumilus 15.1 spores were between 2.67 and 350 times more resistant to UV radiation while the vegetative cells of B. pumilus 15.1 were almost up to 3 orders of magnitude more resistant than the model strain. We performed electron microscopy for morphological characterization, and we observed geometric structures resembling the parasporal crystal inclusions synthesized by Bacillus thuringiensis. Some of the results obtained here such as the parasporal inclusion bodies produced by B. pumilus 15.1 could potentially represent virulence factors of this novel and potentially interesting strain.


Asunto(s)
Bacillus pumilus/fisiología , Bacillus thuringiensis/metabolismo , Ceratitis capitata/microbiología , Cuerpos de Inclusión/metabolismo , Animales , Bacillus pumilus/crecimiento & desarrollo , Bacillus pumilus/efectos de la radiación , Bacillus pumilus/ultraestructura , Bacillus thuringiensis/crecimiento & desarrollo , Bacillus thuringiensis/efectos de la radiación , Bacillus thuringiensis/ultraestructura , Cuerpos de Inclusión/ultraestructura , Microscopía Electrónica , Esporas Bacterianas/metabolismo , Esporas Bacterianas/efectos de la radiación , Esporas Bacterianas/ultraestructura , Rayos Ultravioleta
19.
Neurocirugia (Astur) ; 27(6): 310-314, 2016.
Artículo en Español | MEDLINE | ID: mdl-27265252

RESUMEN

Pituitary apoplexy is usually the result of hemorrhagic infarction in a pituitary adenoma. The clinical presentation varies widely and includes asymptomatic cases, classical pituitary apoplexy and even sudden death. Cerebral ischemia due to pituitary apoplexy is very rare. It may be caused by vasospasm or direct compression of cerebral vessels by the tumor. We report a case of pituitary apoplexy associated with cerebral infarction and discuss the relationship between the two events.


Asunto(s)
Infarto Cerebral/etiología , Apoplejia Hipofisaria/complicaciones , Adenoma , Adulto , Isquemia Encefálica , Femenino , Humanos , Neoplasias Hipofisarias
20.
Neurocirugia (Astur) ; 27(3): 103-11, 2016.
Artículo en Español | MEDLINE | ID: mdl-26589663

RESUMEN

OBJECTIVE: The aim of this study is to analyse the clinical findings and surgical results in a series of patients with bilateral chronic subdural haematoma (BCSDH), and compare the results with a series of patients treated for unilateral chronic subdural haematoma (UCSDH). PATIENTS AND METHODS: A retrospective study was performed on 1523 patients diagnosed and surgically treated for chronic subdural haematoma over a period of 30 years. Patients were divided into 2 groups: The study group consisting of 190 patients operated on for a BCSDH and the control group consisting of patients operated on for an UCSDH (1333 cases). RESULTS: The patient series included 126 males (66.3%) and 64 females (33.7%), with a mean age at diagnosis of 74.8±10.2. The control group consisted of 870 males (65.2%) and 463 women (34.8%), with a mean age of 73.2±12.1. The most common presenting symptoms was cognitive impairment in 63 patients (33.2%) with BCSDH and 416 (29.5%) with UCSDH. Recurrence rates were 9.4% (18 patients) and 5.7% (77 patients) in unilateral and bilateral haematomas, respectively. The mortality was 10 patients (5.2%) with BCSDH and 55(4%) with UCSDH. Factors significantly related to recurrence in the univariate analysis were being male (P=.040), anticoagulant/antiplatelet therapy (P=.032), and poor neurological status at admission (P=.039). CONCLUSIONS: This study indicates that BCSDH is more frequent in males, and the most common presentation is headache. The most important factors influencing recurrences are being male, intake of anticoagulant-antiaggregant drugs, and worse clinical status at admission.


Asunto(s)
Hematoma Subdural Crónico/cirugía , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Hematoma Subdural Crónico/patología , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Adulto Joven
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA