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1.
Environ Microbiol ; 22(6): 2230-2242, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32202357

RESUMEN

The two As resistance arsRBC operons of Pseudomonas putida KT2440 are followed by a downstream gene called arsH that encodes an NADPH-dependent flavin mononucleotide reductase. In this work, we show that the arsH1 and (to a lesser extent) arsH2 genes of P. putida KT2440 strengthened its tolerance to both inorganic As(V) and As(III) and relieved the oxidative stress undergone by cells exposed to either oxyanion. Furthermore, overexpression of arsH1 and arsH2 endowed P. putida with a high tolerance to the oxidative stress caused by diamide (a drainer of metabolic NADPH) in the absence of any arsenic. To examine whether the activity of ArsH was linked to a direct action on the arsenic compounds tested, arsH1 and arsH2 genes were expressed in Escherichia coli, which has an endogenous arsRBC operon but lacks an arsH ortholog. The resulting clones both deployed a lower production of reactive oxygen species (ROS) when exposed to As salts and had a superior endurance to physiological redox insults. These results suggest that besides the claimed direct action on organoarsenicals, ArsH contributes to relieve toxicity of As species by mediating reduction of ROS produced in vivo upon exposure to the oxyanion, e.g. by generating FMNH2 to fuel ROS-quenching activities.


Asunto(s)
Arsénico/toxicidad , Proteínas Bacterianas/genética , Tolerancia a Medicamentos/genética , FMN Reductasa/genética , Pseudomonas putida/genética , Escherichia coli/genética , Operón , Estrés Oxidativo , Pseudomonas putida/metabolismo , Especies Reactivas de Oxígeno/metabolismo
2.
Environ Microbiol ; 18(4): 1122-36, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26487573

RESUMEN

Hydrothermal vents represent a deep, hot, aphotic biosphere where chemosynthetic primary producers, fuelled by chemicals from Earth's subsurface, form the basis of life. In this study, we examined microbial mats from two distinct volcanic sites within the Hellenic Volcanic Arc (HVA). The HVA is geologically and ecologically unique, with reported emissions of CO2 -saturated fluids at temperatures up to 220°C and a notable absence of macrofauna. Metagenomic data reveals highly complex prokaryotic communities composed of chemolithoautotrophs, some methanotrophs, and to our surprise, heterotrophs capable of anaerobic degradation of aromatic hydrocarbons. Our data suggest that aromatic hydrocarbons may indeed be a significant source of carbon in these sites, and instigate additional research into the nature and origin of these compounds in the HVA. Novel physiology was assigned to several uncultured prokaryotic lineages; most notably, a SAR406 representative is attributed with a role in anaerobic hydrocarbon degradation. This dataset, the largest to date from submarine volcanic ecosystems, constitutes a significant resource of novel genes and pathways with potential biotechnological applications.


Asunto(s)
Archaea/clasificación , Archaea/genética , Bacterias/clasificación , Bacterias/genética , Ecosistema , Respiraderos Hidrotermales/microbiología , Archaea/aislamiento & purificación , Bacterias/aislamiento & purificación , Secuencia de Bases , Geología , Metagenómica , ARN Ribosómico 16S/genética , Temperatura
3.
Environ Microbiol ; 17(9): 3330-40, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25684119

RESUMEN

Phosphinothricin (PPT) is a non-specific inhibitor of glutamine synthetase that has been employed as herbicide for selection of transgenic plants expressing cognate resistance genes. While the soil bacterium Pseudomonas putida KT2440 has been generally considered PPT-sensitive, inspection of its genome sequence reveals the presence of two highly similar open reading frames (PP_1924 and PP_4846) encoding acetylases with a potential to cause tolerance to the herbicide. To explore this possibility, each of these genes (named phoN1 and phoN2) was separately cloned and their activities examined in vivo and in vitro. Genetic and biochemical evidence indicated that phoN1 encodes a bona fide PPT-acetyl transferase, the expression of which suffices to make P. putida tolerant to high concentrations of the herbicide. In contrast, PhoN2 does not act on PPT but displays instead activity against methionine sulfoximine (MetSox), another glutamine synthetase inhibitor. When the geometry of the substrate-binding site of PhoN1 was grafted with the equivalent residues of the predicted PhoN2 structure, the resulting protein increased significantly MetSox resistance of the expression host concomitantly with the loss of activity on PPT. These observations uncover intricate biochemical and genetic interactions among soil microorganisms and how they can be perturbed by exposure to generic herbicides in soil.


Asunto(s)
Acetiltransferasas/metabolismo , Aminobutiratos/farmacología , Farmacorresistencia Bacteriana , Herbicidas/farmacología , Metionina Sulfoximina/metabolismo , Pseudomonas putida/enzimología , Acetiltransferasas/genética , Secuencia de Aminoácidos , Aminobutiratos/metabolismo , Secuencia de Bases , Clonación Molecular , Glutamato-Amoníaco Ligasa/antagonistas & inhibidores , Herbicidas/metabolismo , Datos de Secuencia Molecular , Plantas Modificadas Genéticamente , Pseudomonas putida/efectos de los fármacos , Pseudomonas putida/genética
4.
Environ Microbiol ; 17(1): 229-38, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24673935

RESUMEN

The genome of the soil bacterium Pseudomonas putida KT2440 bears two virtually identical arsRBCH operons putatively encoding resistance to inorganic arsenic species. Single and double chromosomal deletions in each of these ars clusters of this bacterium were tested for arsenic sensitivity and found that the contribution of each operon to the resistance to the metalloid was not additive, as either cluster sufficed to endow cells with high-level resistance. However, otherwise identical traits linked to each of the ars sites diverged when temperature was decreased. Growth of the various mutants at 15°C (instead of the standard 30°C for P. putida) uncovered that ars2 affords a much higher resistance to As (III) than the ars1 counterpart. Reverse transcription polymerase chain reaction of arsB1 and arsB2 genes as well as lacZ fusions to the Pars1 and Pars2 promoters traced the difference to variations in transcription of the corresponding gene sets at each temperature. Functional redundancy may thus be selected as a stable condition - rather than just as transient state - if it affords one key activity to be expressed under a wider range of physicochemical settings. This seems to provide a straightforward solution to regulatory problems in environmental bacteria that thrive under changing scenarios.


Asunto(s)
Arsénico/toxicidad , Operón , Pseudomonas putida/genética , Farmacorresistencia Bacteriana/genética , Regulación Bacteriana de la Expresión Génica , Regiones Promotoras Genéticas , Pseudomonas putida/efectos de los fármacos , Temperatura
5.
Nucleic Acids Res ; 41(Database issue): D666-75, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23180763

RESUMEN

The 'Standard European Vector Architecture' database (SEVA-DB, http://seva.cnb.csic.es) was conceived as a user-friendly, web-based resource and a material clone repository to assist in the choice of optimal plasmid vectors for de-constructing and re-constructing complex prokaryotic phenotypes. The SEVA-DB adopts simple design concepts that facilitate the swapping of functional modules and the extension of genome engineering options to microorganisms beyond typical laboratory strains. Under the SEVA standard, every DNA portion of the plasmid vectors is minimized, edited for flaws in their sequence and/or functionality, and endowed with physical connectivity through three inter-segment insulators that are flanked by fixed, rare restriction sites. Such a scaffold enables the exchangeability of multiple origins of replication and diverse antibiotic selection markers to shape a frame for their further combination with a large variety of cargo modules that can be used for varied end-applications. The core collection of constructs that are available at the SEVA-DB has been produced as a starting point for the further expansion of the formatted vector platform. We argue that adoption of the SEVA format can become a shortcut to fill the phenomenal gap between the existing power of DNA synthesis and the actual engineering of predictable and efficacious bacteria.


Asunto(s)
Bases de Datos Genéticas , Vectores Genéticos , Plásmidos/genética , Bacterias/genética , Clonación Molecular , Farmacorresistencia Microbiana/genética , Vectores Genéticos/normas , Internet , Fenotipo , Regiones Promotoras Genéticas , Origen de Réplica , Terminología como Asunto
6.
J Clin Microbiol ; 52(5): 1423-8, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24554744

RESUMEN

Clostridium difficile-associated diarrhea is a well-recognized complication of antibiotic use. Historically, diagnosing C. difficile has been difficult, as antigen assays are insensitive and culture-based methods require several days to yield results. Nucleic acid amplification tests (NAATs) are quickly becoming the standard of care. We compared the performance of two automated investigational/research use only (IUO/RUO) NAATs for the detection of C. difficile toxin genes, the IMDx C. difficile for Abbott m2000 Assay (IMDx) and the BD Max Cdiff Assay (Max). A prospective analysis of 111 stool specimens received in the laboratory for C. difficile testing by the laboratory's test of record (TOR), the BD GeneOhm Cdiff Assay, and a retrospective analysis of 88 specimens previously determined to be positive for C. difficile were included in the study. One prospective specimen was excluded due to loss to follow-up discrepancy analysis. Of the remaining 198 specimens, 90 were positive by all three methods, 9 were positive by TOR and Max, and 3 were positive by TOR only. One negative specimen was initially inhibitory by Max. The remaining 95 specimens were negative by all methods. Toxigenic C. difficile culture was performed on the 12 discrepant samples. True C. difficile-positive status was defined as either positive by all three amplification assays or positive by toxigenic culture. Based on this definition, the sensitivity and specificity were 96.9% and 95% for Max and 92.8% and 100% for IMDx. In summary, both highly automated systems demonstrated excellent performance, and each has individual benefits, which will ensure that they will both have a niche in clinical laboratories.


Asunto(s)
Bioensayo/métodos , Clostridioides difficile/genética , Infecciones por Clostridium/diagnóstico , Técnicas de Diagnóstico Molecular/métodos , Proteínas Bacterianas/genética , Toxinas Bacterianas/genética , Infecciones por Clostridium/microbiología , Diarrea/diagnóstico , Diarrea/microbiología , Enterotoxinas/genética , Heces/microbiología , Humanos , Técnicas de Amplificación de Ácido Nucleico/métodos , Estudios Prospectivos , Juego de Reactivos para Diagnóstico , Estudios Retrospectivos , Sensibilidad y Especificidad
7.
Plant Dis ; 98(8): 1162, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30708800

RESUMEN

In March 2013, symptoms of mild leaf curling, mosaic, and interveinal yellowing were observed in tobacco (Nicotiana tabacum) plants grown in a row surrounding the exterior of a greenhouse containing a tomato crop in Guía de Isora, Tenerife (Canary Islands, Spain). The tobacco plants were found lightly infested by the whitefly (Hemiptera: Aleyrodidae) Bemisia tabaci. The greenhouses in this area are devoted to the commercial production of tomato. The farmers grow some tobacco plants inside and outside of them as a reservoir of parasitoids and depredators of B. tabaci. This insect is the natural vector of the main viruses severely affecting tomato in the Canary Islands, the begomovirus Tomato yellow leaf curl virus and the crinivirus Tomato chlorosis virus (ToCV). ToCV was detected in Spain in 1997 (2) and has become established in most of the coastal provinces of eastern and southern continental Spain and in the Canary Islands. Approximately 50% of the tomato plants grown inside the greenhouse close to the tobacco plants showed typical ToCV symptoms, and infection by this virus was confirmed in the seven plants tested by reverse transcription (RT)-PCR using specific coat protein gene (CP) primers (see below). Total RNA was extracted with TRIzol Reagent (Invitrogen) from leaves of five tobacco plants showing the symptoms mentioned above and analyzed by dot-blot hybridization using digoxigenin-labeled RNA probes to the CP gene of ToCV. Positive signal was obtained for all five plants. RT-PCR reactions were performed with specific primers for the detection of ToCV, MA380(+) (5'-GTGAGACCCCGATGACAGAT-3') and MA381(-) (5'-TACAGTTCCTTGCCCTCGTT-3'), specific to the CP gene (ToCV RNA 2) (3), and MA396(+) (5'-TGGTCGAACAGTTTGAGAGC-3') and MA397(-) (5'-TGAACTCGAATTGGGACAGA-3'), specific to the RNA-dependent RNA polymerase (RdRp) gene (ToCV RNA 1) (1). DNA fragments of the expected size (436 and 763 bp, respectively) were obtained, thus supporting the presence of ToCV in the symptomatic samples. The amplified product of the RdRp gene fragment from one sample was directly sequenced (Macrogen Inc., South Korea) and resulted closely related to ToCV isolates from Sudan (GenBank Accession No. JN411686, 99.6% nt identity) and Spain (DQ983480, 99.4% nt identity), thereby confirming the infection by this virus. Partial sequence of the ToCV isolate from tobacco was deposited in GenBank under accession no. KJ175084. In addition, all five plants resulted positive when analyzed by ELISA for Tomato spotted wilt virus and Potato virus Y and by PCR for Tomato yellow leaf curl virus (data not shown), all three viruses reported to infect naturally tobacco. Although tobacco has been reported as an experimental host of ToCV (4), to our knowledge, this is the first report of this species as a natural host of this virus. The finding of ToCV infecting tobacco raises the question of whether this virus could emerge as a pathogen of this crop and questions the use that farmers make of tobacco as reservoirs of natural enemies for whitefly control in tomato. References: (1) G. Lozano et al. J. Virol. 83:12973, 2009. (2) J. Navas-Castillo et al. Plant Dis. 84:835, 2000. (3) H. P. Trenado et al. Eur. J. Plant Pathol. 118:193, 2007 (4) W. M. Wintermantel and G. C. Wisler. Plant Dis. 90:814, 2006.

8.
Environ Microbiol ; 13(4): 960-74, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21219561

RESUMEN

Functional studies of biodegradative activities in environmental microorganisms require molecular tools for monitoring catabolic enzymes in the members of the native microbiota. To this end, we have generated repertories of single-domain V(HH) fragments of camel immunoglobulins (nanobodies) able to interact with multiple proteins that are descriptors of environmentally relevant processes. For this, we immunized Camelus dromedarius with a cocktail of up to 12 purified enzymes that are representative of major types of detoxifying activities found in aerobic and anaerobic microorganisms. Following the capture of the antigen-binding modules from the mRNA of the camel lymphocytes and the selection of sub-libraries for each of the enzymes in a phage display system we found a large number of V(HH) modules that interacted with each of the antigens. Those associated to the enzyme 2,3 dihydroxybiphenyl dioxygenase of Burkholderia xenovorans LB400 (BphC) and the arsenate reductase of Staphylococcus aureus (ArsC) were examined in detail and found to hold different qualities that were optimal for distinct protein recognition procedures. The repertory of anti-BphC V(HH) s included variants with a strong affinity and specificity for linear epitopes of the enzyme. When the anti-BphC V(HH) library was recloned in a prokaryotic intracellular expression system, some nanobodies were found to inhibit the dioxygenase activity in vivo. Furthermore, anti-ArsC V(HH) s were able to discriminate between proteins stemming from different enzyme families. The easiness of generating large collections of binders with different properties widens considerably the molecular toolbox for analysis of biodegradative bacteria and opens fresh possibilities of monitoring protein markers and activities in the environment.


Asunto(s)
Arseniato Reductasas/metabolismo , Burkholderia/enzimología , Dioxigenasas/metabolismo , Cadenas Pesadas de Inmunoglobulina/biosíntesis , Staphylococcus aureus/enzimología , Animales , Arseniato Reductasas/inmunología , Proteínas Bacterianas/inmunología , Proteínas Bacterianas/metabolismo , Biodegradación Ambiental , Camelus/inmunología , Dioxigenasas/inmunología , Biblioteca de Genes , Masculino , Modelos Moleculares , Biblioteca de Péptidos , Análisis de Secuencia de Proteína
9.
Microbiol Spectr ; 9(3): e0191021, 2021 12 22.
Artículo en Inglés | MEDLINE | ID: mdl-34937173

RESUMEN

Due to their phylogenetic proximity to humans, nonhuman primates (NHPs) are considered an adequate choice for a basic and preclinical model of sepsis. Gram-negative bacteria are the primary causative of sepsis. During infection, bacteria continuously release the potent toxin lipopolysaccharide (LPS) into the bloodstream, which triggers an uncontrolled systemic inflammatory response leading to death. Our previous research has demonstrated in vitro and in vivo using a mouse model of septic shock that Fh15, a recombinant variant of the Fasciola hepatica fatty acid binding protein, acts as an antagonist of Toll-like receptor 4 (TLR4) suppressing the LPS-induced proinflammatory cytokine storm. The present communication is a proof-of concept study aimed to demonstrate that a low-dose of Fh15 suppresses the cytokine storm and other inflammatory markers during the early phase of sepsis induced in rhesus macaques by intravenous (i.v.) infusion with lethal doses of live Escherichia coli. Fh15 was administered as an isotonic infusion 30 min prior to the bacterial infusion. Among the novel findings reported in this communication, Fh15 (i) significantly prevented bacteremia, suppressed LPS levels in plasma, and the production of C-reactive protein and procalcitonin, which are key signatures of inflammation and bacterial infection, respectively; (ii) reduced the production of proinflammatory cytokines; and (iii) increased innate immune cell populations in blood, which suggests a role in promoting a prolonged steady state in rhesus macaques even in the presence of inflammatory stimuli. This report is the first to demonstrate that a F. hepatica-derived molecule possesses potential as an anti-inflammatory drug against sepsis in an NHP model. IMPORTANCE Sepsis caused by Gram-negative bacteria affects 1.7 million adults annually in the United States and is one of the most important causes of death at intensive care units. Although the effective use of antibiotics has resulted in improved prognosis of sepsis, the pathological and deathly effects have been attributed to the persistent inflammatory cascade. There is a present need to develop anti-inflammatory agents that can suppress or neutralize the inflammatory responses and prevent the lethal consequences of sepsis. We demonstrated here that a small molecule of 14.5 kDa can suppress the bacteremia, endotoxemia, and many other inflammatory markers in an acute Gram-negative sepsis rhesus macaque model. These results reinforce the notion that Fh15 constitutes an excellent candidate for drug development against sepsis.


Asunto(s)
Antiinflamatorios/administración & dosificación , Bacteriemia/tratamiento farmacológico , Fasciola hepatica/metabolismo , Proteínas de Unión a Ácidos Grasos/administración & dosificación , Bacterias Gramnegativas/fisiología , Proteínas del Helminto/administración & dosificación , Animales , Antiinflamatorios/metabolismo , Bacteriemia/genética , Bacteriemia/inmunología , Bacteriemia/microbiología , Citocinas/genética , Citocinas/inmunología , Modelos Animales de Enfermedad , Fasciola hepatica/química , Fasciola hepatica/genética , Proteínas de Unión a Ácidos Grasos/genética , Proteínas de Unión a Ácidos Grasos/metabolismo , Bacterias Gramnegativas/clasificación , Bacterias Gramnegativas/genética , Proteínas del Helminto/genética , Proteínas del Helminto/metabolismo , Humanos , Macaca mulatta , Masculino , Proteínas Recombinantes/administración & dosificación , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Receptor Toll-Like 4/antagonistas & inhibidores , Receptor Toll-Like 4/genética , Receptor Toll-Like 4/inmunología
10.
Plant Dis ; 92(5): 831, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-30769603

RESUMEN

Tomato torrado virus (ToTV) is a recently identified Picorna-like virus that causes "torrado disease" in tomatoes (4). Typical symptoms of "torrado disease" seen in tomato crops (Solanum lycopersicum L. formerly Lycopersicon esculentum L.) were initially defined as yellow areas at the base of the leaflet that later developed into necrotic spots that sometimes abscised, leaving holes in the leaflet. Other plants showed extensive necrosis progressing from the base to the tip of the leaflet. Fruits were distorted with necrotic lines on the surface that often cracked. Affected plants had a burnt-like appearance and the production was seriously reduced. These symptoms have been observed in tomato crops in Murcia (Spain) and the Canary Islands (Spain) (1). To identify possible alternative hosts that may serve as virus reservoirs, samples of 72 different common weed species were collected in greenhouses in Murcia and the Canary Islands where "torrado disease" symptoms were observed in tomatoes. Forty-seven showed virus-like symptoms and 25 were asymptomatic. Symptoms included mild mosaic, blistering, vein clearing, interveinal yellowing, yellow spots, necrosis, leaf distortion, and curling. Samples were analyzed by one-step reverse transcription (RT)-PCR using primers specific for ToTV to amplify 580 bp of the polyprotein region of RNA2 (3) and dot-blot hybridization with a digoxygenin-labeled RNA probe complementary to the same portion of the ToTV genome. Twenty-two of the 72 weed samples belonging to Amaranthus sp. (Amaranthaceae); Spergularia sp. (Caryophyllaceae); Atriplex sp., Chenopodium ambrosioides L., Chenopodium sp., and Halogetum sativus (Loef. ex L.) Moq. (Chenopodiaceae); Senebiera didyma Pers. (Cruciferae); Malva sp. (Malvacae); Polygonum sp. (Polygonaceae); and Nicotiana glauca Graham and Solanum nigrum L. (Solanaceae) were positive for ToTV by molecular hybridization (10 samples) and RT-PCR (22 samples, including the samples positive by molecular hybridization). PCR products obtained from Atriplex sp. (Canary Islands) and S. didyma (Murcia) were sequenced (GenBank Accessions EU090252 and EU090253). BLAST analysis showed 99% identity to ToTV RNA2 sequence (GenBank Accession DQ388880). Two tomato plants were positive for ToTV by RT-PCR after mechanical back-inoculation, although no symptoms were observed. This study showed ToTV infects common weeds present in Spanish tomato crops. Recently, Trialeurodes vaporariorum has been reported to transmit ToTV (2), although the efficiency of transmission is unknown. The vector-assisted transmission of ToTV could explain the infection of weeds in affected greenhouses. To our knowledge, this is the first report of natural infection of weeds by ToTV. References: (1) A. Alfaro-Fernández et al. Plant Dis. 91:1060, 2007. (2) H. Pospieszny et al. Plant Dis. 91:1364, 2007. (3) J. Van der Heuvel et al. Plant Virus Designated Tomato Torrado Virus. Online publication. World Intellectual Property Organization WO/2006/085749, 2006. (4) M. Verbeek et al. Arch. Virol. 152:881, 2007.

11.
Artículo en Inglés, Español | MEDLINE | ID: mdl-28645685

RESUMEN

OBJECTIVES: Cortical posterior hypometabolism on PET imaging with 18F-FDG (FDG-PET), and altered levels of Aß1-42 peptide, total Tau (tTau) and phosphorylated Tau (pTau) proteins in cerebrospinal fluid (CSF) are established diagnostic biomarkers in Alzheimer's disease (AD). An evaluation has been made of the concordance and relationship between the results of FDG-PET and CSF biomarkers in symptomatic patients with suspected AD. MATERIAL AND METHODS: A retrospective review was carried out on 120 patients with cognitive impairment referred to our Cognitive Neurology Unit, and who were evaluated by brain FDG-PET and a lumbar puncture for CSF biomarkers. In order to calculate their Kappa coefficient of concordance, the result of the FDG-PET and the set of the three CSF biomarkers in each patient was classified as normal, inconclusive, or AD-compatible. The relationship between the results of both methods was further assessed using logistic regression analysis, including the Aß1-42, tTau and pTau levels as quantitative predictors, and the FDG-PET result as the dependent variable. RESULTS: The weighted Kappa coefficient between FDG-PET and CSF biomarkers was 0.46 (95% CI: 0.35-0.57). Logistic regression analysis showed that the Aß1-42 and tTau values together were capable of discriminating an FDG-PET result metabolically suggestive of AD from one non-suggestive of AD, with a 91% sensitivity and 93% specificity at the cut-off line Aß1-42=44+1.3×tTau. CONCLUSIONS: The level of concordance between FDG-PET and CSF biomarkers was moderate, indicating their complementary value in diagnosing AD. The Aß1-42 and tTau levels in CSF help to predict the patient FDG-PET cortical metabolic status.


Asunto(s)
Enfermedad de Alzheimer/diagnóstico , Biomarcadores/líquido cefalorraquídeo , Encéfalo/diagnóstico por imagen , Radioisótopos de Flúor , Fluorodesoxiglucosa F18 , Tomografía de Emisión de Positrones/métodos , Radiofármacos , Enfermedad de Alzheimer/líquido cefalorraquídeo , Enfermedad de Alzheimer/diagnóstico por imagen , Péptidos beta-Amiloides/líquido cefalorraquídeo , Humanos , Fragmentos de Péptidos/líquido cefalorraquídeo , Fosfoproteínas/líquido cefalorraquídeo , Estudios Retrospectivos , Sensibilidad y Especificidad , Proteínas tau/líquido cefalorraquídeo
12.
Sci Rep ; 8(1): 7787, 2018 05 17.
Artículo en Inglés | MEDLINE | ID: mdl-29773890

RESUMEN

Previous studies have established that an increased Th-9 response creates a hostile environment for nematode parasites. Given that IL-23, a cytokine required for maintenance of the IL-17-secreting phenotype, has inhibitory effects on IL-9 production, we hypothesized that reducing circulating IL-23 by treatment with anti-IL-23 antibodies would reduce the establishment and development of parasitic intestinal nematodes. In this study, we show that animals treated with anti-IL-23 monoclonal antibodies showed a drastic reduction in the number of mouse pinworms (Aspiculuris tetraptera) recovered from the intestine (p < 0.001) at 23 days post-infection compared to the untreated animals. The cytokine levels in Peyer's patches (PP) in treated and infected animals increase the expression of interleukins such as IL-25, IL-21, and IL-9, augmenting mucus production in the crypts, and boosting chemokines, such as OX40 and CCL20 in the mucosa. Our results suggest that the Th17/Th2 regulatory mechanism provoked by the administration of the anti-IL-23 antibody prevents the implantation of the intestinal nematode in mice. The diminished inflammatory IL-17 levels alter the Th9 environment perhaps as a consequence of IL-17 inhibiting IL-9 expression. These Th9 conditions may explain the successful treatment against Inflammatory Bowel Disease (IBD) both with antibodies against IL-23 or through parasitization with nematodes.


Asunto(s)
Anticuerpos Monoclonales/uso terapéutico , Interleucina-23/inmunología , Infecciones por Nematodos/prevención & control , Animales , Anticuerpos Monoclonales/administración & dosificación , Inyecciones Intraperitoneales , Interleucinas/metabolismo , Intestinos/parasitología , Masculino , Ratones , Ratones Endogámicos ICR , Carga de Parásitos
13.
Plant Dis ; 91(8): 1060, 2007 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30780469

RESUMEN

In 2003, greenhouse-grown tomato crops (Lycopersicon esculentum Mill.) in the Canary Islands (Spain) were observed showing an initial yellowing in defined areas at the base of the leaflet that later developed into necrotic spots or an extensive necrotic area progressing from the base to tip. Fruits were also affected, showing necrotic areas and often developing cracking. Generally, the plants that were affected seemed to be burnt, their growth was reduced, and the production level was seriously damaged. Similar symptoms have been observed in Murcia (Spain) since 2001, which have been recently associated with Tomato torrado virus (ToTV) infection (2). Twenty-two tomato samples showing "torrado disease" symptoms were collected from different greenhouses between 2003 and 2006 in Las Palmas (Canary Islands, Spain). To verify the identity of the disease, double-antibody sandwich (DAS)-ELISA was performed on leaf and fruit extracts of symptomatic plants using polyclonal antibodies specific to Potato virus Y (PVY), Tomato mosaic virus (ToMV), Tomato spotted wilt virus (TSWV) (Loewe Biochemica, Sauerlach, Germany), and Pepino mosaic virus (PepMV) (DSMZ, Braunschweig, Germany). Total RNA was extracted from the 22 tomato samples with the RNAwiz Extraction kit (Ambion, Huntingdon, United Kingdom) and tested using one-step reverse-transcription (RT)-PCR with the SuperScript Platinum Taq kit (Invitrogen Life Technologies, Barcelona, Spain) with primers specific to PepMV (1) and ToTV (2). All analyses included healthy tomato plants as negative controls. Five of the twenty-two tomato samples were positive for PepMV and negative for the other viruses tested by serological analysis. However, all 22 samples were positive in RT-PCR performed with the primers specific to ToTV segment RNA2. The RT-PCR assay to detect ToTV produced an amplicon of the expected size (580 bp). No amplification product was observed when healthy plants or a water control were used as a template in the RT-PCR reaction. The ToTV RT-PCR product was purified (High Pure PCR Product Purification kit, Roche Diagnostics, Mannheim, Germany) and sequenced. BLAST analysis of one sequence (GenBank Accession No. EF436286) showed 99% identity to ToTV RNA2 sequence (GenBank Accession No. DQ388880). To our knowledge, this is the first report of ToTV in the Canary Islands. References: (1) I. Pagán et al. Phytopathology 96:274, 2006. (2) M. Verbeek et al. Online Publication. doi:10.1007/s00705-006-0917-6. Arch. Virol., 2007.

14.
Open Biol ; 7(4)2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-28404797

RESUMEN

Despite the importance of the adjuvant in the immunization process, very few adjuvants merge with the antigens in vaccines. A synthetic self-adjuvant oleic-vinyl sulfone (OVS) linked to the catalytic region of recombinant serine/threonine phosphatase 2A from the nematode Angiostrongylus costaricensis (rPP2A) was used for intranasal immunization in mice previously infected with Trichuris muris The animal intranasal immunization with rPP2A-OVS showed a reduction of 99.01% in the number of the nematode eggs and 97.90% in adult. The immunohistochemical analysis of the intestinal sections showed that in immunized animals with lipopeptide the mucus was significantly higher than in the other experimental groups. Also, these animals presented significantly different chemokine, CCL20 and CCL11, levels. However, although the number and size of Tuft cells did not vary between groups, the intensity of fluorescence per cell was significant in the group immunized with the rPP2A-OVS. The results of the present study suggest that mice immunized with the lipopeptide are capable of activating a combined Th17/Th9 response. This strategy of immunization may be of great applicability not only in immunotherapy and immunoprophylaxis to control diseases caused by nematodes but also in pathologies necessitating action at the level of the Th9 response in the intestinal mucosa.


Asunto(s)
Adyuvantes Inmunológicos/administración & dosificación , Proteínas del Helminto/administración & dosificación , Lipopéptidos/administración & dosificación , Proteína Fosfatasa 2/administración & dosificación , Sulfonas/administración & dosificación , Tricuriasis/prevención & control , Vacunas Conjugadas/administración & dosificación , Adyuvantes Inmunológicos/síntesis química , Administración Intranasal , Secuencia de Aminoácidos , Animales , Quimiocina CCL11/genética , Quimiocina CCL11/inmunología , Quimiocina CCL20/genética , Quimiocina CCL20/inmunología , Femenino , Expresión Génica , Proteínas del Helminto/biosíntesis , Proteínas del Helminto/inmunología , Interleucinas/genética , Interleucinas/inmunología , Mucosa Intestinal/efectos de los fármacos , Mucosa Intestinal/inmunología , Mucosa Intestinal/parasitología , Lipopéptidos/biosíntesis , Lipopéptidos/inmunología , Ratones , Ratones Endogámicos AKR , Recuento de Huevos de Parásitos , Proteína Fosfatasa 2/biosíntesis , Proteína Fosfatasa 2/inmunología , Proteínas Recombinantes/administración & dosificación , Proteínas Recombinantes/biosíntesis , Proteínas Recombinantes/inmunología , Alineación de Secuencia , Sulfonas/química , Sulfonas/inmunología , Células Th17/efectos de los fármacos , Células Th17/inmunología , Células Th17/parasitología , Tricuriasis/inmunología , Tricuriasis/parasitología , Trichuris/efectos de los fármacos , Trichuris/inmunología
15.
J Neurosci Methods ; 152(1-2): 18-31, 2006 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-16185769

RESUMEN

We have developed a new quantitative analysis of spiral drawing that is able to evaluate any spiral execution and it has not temporal or spatial limitations in the obtaining of specimens. Thirty-one patients with action tremor and 24 control subjects were asked to draw an Archimedes spiral over a print template. Specimens were scanned and then treated through a semiautomatic computer program that reconstructs the temporal sequence of the spiral drawing by the subject. The spirals were first analysed by means of the cross-correlation coefficient with the spiral template. Secondly, the mean and the standard deviation of the distance between each point of the spiral drawing and the corresponding point of the spiral model were determined. Finally, the reconstructed spiral was analysed using the Fourier Transform. Its results were interpreted with the aid of a computer model of a tremulous spiral. The experimental variables were greater in the patients group respect to age-matched controls. There was also a high linear correlation between them and the clinical score given by three neurologists. Finally, Receiver Operating Characteristic (ROC) curves analysis shown that the method classified the spirals better than human ratters.


Asunto(s)
Procesamiento de Imagen Asistido por Computador/métodos , Destreza Motora/fisiología , Movimiento/fisiología , Adulto , Anciano , Anciano de 80 o más Años , Algoritmos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Curva ROC , Temblor/fisiopatología
16.
Anim Reprod Sci ; 167: 133-8, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26944772

RESUMEN

This study aimed to determine the possible effects of a single injection of human chorionic gonadotropin (hCG) as a means for estrus induction in acyclic French-Alpine goats during the reproductive transition period at 25°N, 103°W. The potential effects of hCG upon ovarian function and reproductive performance of goats were also assessed. Multiparous acyclic French-Alpine goats (n = 39; 37.4 ± 8 .5 kg) were primed with 20mg progesterone (P4) 1 day prior to hCG administration. Thereafter, does were treated either with saline (hCG-0; n = 10), 50 (hCG-50; n = 9), 100 (hCG-100; n = 10), or 300 IU of hCG (hCG-300; n = 10). Ovarian structures and pregnancy were monitored by transrectal ultrasonography. In addition, after hCG application, goats were monitored twice daily (0800 and 1800 h) to detect estrus signs, with the use of aproned, sexually active bucks treated with testosterone. Goats were bred 12h after the onset of estrus. Two days after hCG administration, the number of large follicles was higher (P < 0.05) in the hCG-50 and hCG-300 groups (1.7 ± 0.1 and 1.8 ± 0.2, respectively) compared with the hCG-100 and hCG-0 groups (1.4 ± 0.2 and 1.1 ± 0.1, respectively). Although none of the hCG-0-goats depicted estrus, the estrus response from the hCG-50, hCG-100, and hCG-300 groups over the 7-d breeding period was 67%, 100%, and 90%, respectively (P > 0.05), being always accompanied by ovulation. Pregnancy rate (67, 100, and 70%), kidding rate (55%, 80%, and 70%), and litter size (1.6 ± 0.5, 1.5 ± 0.5, and 1.5 ± 0.5) for hCG-50, hCG-100, and hCG-300, respectively, did not differ among the hCG-treated does. Therefore, the combined use of P4-priming plus a 100-IU hCG injection is an effective protocol for inducing estrus in non-cycling Alpine goats during the anestrus-to-estrus transition period, which is of key importance for both goat producers and industrializers.


Asunto(s)
Gonadotropina Coriónica/farmacología , Ciclo Estral/efectos de los fármacos , Cabras/fisiología , Progesterona/farmacología , Sustancias para el Control de la Reproducción/farmacología , Animales , Femenino , Embarazo
17.
Rev Neurol ; 40(3): 159-62, 2005.
Artículo en Español | MEDLINE | ID: mdl-15750901

RESUMEN

INTRODUCTION: Serotonin is a neurotransmitter synthesized from tryptophan. It is implied in the regulation of mood, cognition, sleep cycle, synthesis of cerebrospinal fluid, and other processes. Generally, it is implied in human pathology by hypofunction. However, there is a complication of unknown incidence related to treatment with drugs that increase the stimulation of 5-HT1A serotonin receptors, called serotonin syndrome (SS). Clinically, it is characterised by the presence of a triad of mental and autonomic disorders, and motor hyperactivity. This entity has not biological markers and its diagnosis could be done verifying the proposed criteria. CASE REPORTS: Two cases of SS are presented, one of them related to the combination of risperidone and sertraline, as first report in the literature. Both cases had a favourable outcome employing support measures. CONCLUSIONS: The physiopathology, the diagnosis, the differential diagnosis, and the treatment are reviewed. We emphasize the potentially high frequency of this disorder, given the growing use of serotonin activity modifying drugs, and the typically benign course of the SS once the support measures are started.


Asunto(s)
Síndrome de la Serotonina/diagnóstico , Síndrome de la Serotonina/fisiopatología , Anciano , Quimioterapia Combinada , Humanos , Masculino , Persona de Mediana Edad , Neuronas/química , Neuronas/metabolismo , Risperidona/efectos adversos , Risperidona/uso terapéutico , Serotonina/metabolismo , Antagonistas de la Serotonina/efectos adversos , Antagonistas de la Serotonina/uso terapéutico , Síndrome de la Serotonina/tratamiento farmacológico , Inhibidores Selectivos de la Recaptación de Serotonina/efectos adversos , Inhibidores Selectivos de la Recaptación de Serotonina/uso terapéutico , Sertralina/efectos adversos , Sertralina/uso terapéutico , Resultado del Tratamiento
18.
Arch Soc Esp Oftalmol ; 90(5): 237-40, 2015 May.
Artículo en Español | MEDLINE | ID: mdl-25443202

RESUMEN

CLINICAL CASE: We report a case of a 31 year-old woman with a sudden visual loss due to a cilioretinal artery occlusion. The physical examinination showed hepatomegaly. Serum iron and ferritin and transferrin saturation were unusually high. The doppler scan of carotid arteries showed no relevant signs of atheromatous disease. Dilated cardiomiopaty was revealed in the B-scan with subendocardial calcium deposits. Genetic tests were positive for hemochromatosis. DISCUSSION: Subendocardial calcification due to hemochromatosis could be the embolic source in our patient. This embolic ocular disease is the first presentation of hemochromatosis in this patient.


Asunto(s)
Arteriopatías Oclusivas/etiología , Arterias Ciliares/patología , Embolia/etiología , Hemocromatosis/complicaciones , Neuropatía Óptica Isquémica/etiología , Arteria Retiniana/patología , Adulto , Calcinosis/etiología , Cardiomiopatía Restrictiva/etiología , Complicaciones de la Diabetes , Femenino , Hemocromatosis/diagnóstico , Hepatomegalia/etiología , Humanos
19.
Am J Clin Nutr ; 62(4): 769-75, 1995 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-7572707

RESUMEN

The effects on plasma lipid concentrations of two oleic acid-rich diets, prepared with two different plant oils--olive oil and sunflower oil high in monounsaturated fatty acids (MUFAs)-- were compared with a National Cholesterol Education Program (NCEP) I diet. Twenty-one healthy, normolipidemic, young males consumed an NCEP-I diet (30% of energy as fat) during a 25-d period. Subjects were then assigned to two 4-wk study periods, according to a randomized, crossover design. Group one was placed on an olive oil-enriched diet (40% fat, 22% MUFAs), followed by a 4-wk period of a sunflower oil-enriched diet (40% fat, 22% MUFAs). In group two, the order of the diets was reversed. Both MUFA dietary periods resulted in an increase in high-density-lipoprotein (HDL) cholesterol (7% for the olive oil diet and 4% for the sunflower oil diet) and in apolipoprotein (apo) A-I (9% for both) compared with the NCEP-I diet. Low-density-lipoprotein (LDL) cholesterol and apo B concentrations (x +/- SEM) were lower (P < 0.05) during the sunflower oil diet (2.40 +/- 0.11 mmol/L, 0.85 +/- 0.04 mg/L) than during the olive oil diet (2.64 +/- 0.15 mmol/L, 0.93 +/- 0.05 mg/L). No significant differences were observed in these variables between the sunflower oil and NCEP-I (2.48 +/- 0.13 mmol/L, 0.89 +/- 0.04 mg/L) diets.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Grasas de la Dieta/administración & dosificación , Lipoproteínas/sangre , Ácidos Oléicos/administración & dosificación , Aceites de Plantas , Adulto , Colesterol/sangre , Estudios Cruzados , Ácidos Grasos Monoinsaturados/administración & dosificación , Ácidos Grasos Insaturados/administración & dosificación , Humanos , Lípidos/sangre , Masculino , Ácidos Oléicos/farmacología , Aceite de Oliva , Aceite de Girasol
20.
Neurology ; 46(3): 673-7, 1996 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-8618665

RESUMEN

Apolipoprotein E type 4 allele (apoE epsilon4) is associated with Alzheimer's disease (AD) in the late-onset familial form and in sporadic cases, but the age-associated risk in a randomly sampled elderly population is not established. We examined the association of apoE epsilon4 with AD and other dementias (mainly multi-infarct or dementia following stroke) in 1,030 persons aged 71 to 100 years in the population-based Framingham Study cohort. Kaplan-Meier survival analysis revealed that 55% of the apoE epsilon4/epsilon4 homozygotes developed AD by age 80, whereas 27% of apoE epsilon3/epsilon4 heterozygotes developed AD by age 85, and 9% of those without a 4 allele developed AD by age 85 years. In comparison with persons without a 4 allele, the risk ration for AD was 3.7 (95% CI = 1.9 to 7.5) for apoE epsilon3/epsilon4 heterozygotes and 30.1 (95% CI = 10.7 to 84.4) for apoE epsilon4 homozygotes. ApoE epsilon2 (2/2, 2/3, or 2/4 genotypes) was associated with an absence of AD. One-half (n=21) of the 43 AD patients were either homozygous or heterozygous for apoE epsilon4. We found evidence for an association of apoE epsilon4 with other dementia, primarily multi-infarct dementia and stroke. The risk ratio was 2.3 (95% CI = 0.9 to 6.1) for non-AD dementias among persons with apoE epsilon3/epsilon4. Although the apoE epsilon4 allele is a potent risk factor for AD and may be associated with other forms of dementia, most apoE epsilon4 carriers do not develop dementia, and about one-half of AD is not apoE epsilon4 associated. The low positive predictive value of this marker (0.10) suggest that use of apoE genotyping as a screening test for AD is not supported.


Asunto(s)
Apolipoproteínas E/genética , Demencia/genética , Adulto , Anciano , Anciano de 80 o más Años , Alelos , Enfermedad de Alzheimer/epidemiología , Enfermedad de Alzheimer/genética , Apolipoproteína E4 , Secuencia de Bases , Estudios de Cohortes , Femenino , Humanos , Incidencia , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Sondas Moleculares/genética , Datos de Secuencia Molecular , Oportunidad Relativa , Sensibilidad y Especificidad
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