Aims: To search for the induction of the expression of antimicrobial peptides in corneal fibroblasts treated with bacterial components. Methods: RT-PCR was performed to search for mRNAs expression of ...antimicrobial peptides and toll-like receptors (TLRs) in murine primary cultures of corneal fibroblast (PCCF) treated with lipopolysaccharide (LPS) from Escherichia coli, peptidoglycan from Staphylococcus aureus, and cytosine-phosphorous-guanine oligonucleotide (CpG-ODN). Cellular activation was blocked with anti-TRL antibodies. Results: LPS did not induce expression of antimicrobial peptide in corneal fibroblasts. Cathelin related antimicrobial peptide (CRAMP) and α-defensin 3 were overexpressed in a time and dose dependent manner in corneal fibroblasts treated with peptidoglycan and with CpG-ODN, respectively. CRAMP expression was blocked when PCCF were treated with anti-TLR-2 antibodies. α-Defensin 3 was not expressed in NIH murine corneal fibroblasts (which do not express the TLR-9 molecule) treated with CpG-ODN. Conclusion: Results suggest that corneal fibroblasts, which are the second cellular barrier of the cornea, can play an important part in the innate immunity of the eye via TLR stimulation.
Staphylococcus epidermidis is a common commensal of healthy conjunctiva and it can cause endophthalmitis, however its presence in conjunctivitis, keratitis and blepharitis is unknown. Molecular ...genotyping of S. epidermidis from healthy conjunctiva could provide information about the origin of the strains that infect the eye. In this paper two collections of S. epidermidis were used: one from ocular infection (n = 62), and another from healthy conjunctiva (n = 45). All isolates were genotyped by pulsed field gel electrophoresis (PFGE), multilocus sequence typing (MLST), staphylococcal cassette chromosome mec (SCCmec), detection of the genes icaA, icaD, IS256 and polymorphism type of agr locus. The phenotypic data included biofilm production and antibiotic resistance. The results displayed 61 PFGE types from 107 isolates and they were highly discriminatory. MLST analysis generated a total of 25 STs, of which 11 STs were distributed among the ocular infection isolates and lineage ST2 was the most frequent (48.4%), while 14 STs were present in the healthy conjunctiva isolates and lineage ST5 was the most abundant (24.4%). By means of a principal coordinates analysis (PCoA) and a discriminant analysis (DA) it was found that ocular infection isolates had as discriminant markers agr III or agr II, SCCmec V or SCCmec I, mecA gene, resistance to tobramycin, positive biofilm, and IS256+. In contrast to the healthy conjunctiva isolates, the discriminating markers were agr I, and resistance to chloramphenicol, ciprofloxacin, gatifloxacin and oxacillin. The discriminant biomarkers of ocular infection were examined in healthy conjunctiva isolates, and it was found that 3 healthy conjunctiva isolates two with ST2 and another with ST9 (3/45, 6.66%) had similar genotypic and phenotypic characteristics to ocular infection isolates, therefore a small population from healthy conjunctiva could cause an ocular infection. These data suggest that the healthy conjunctiva isolates do not, in almost all cases, infect the eye due to their large genotypic and phenotypic difference with the ocular infection isolates.
HLA class II, p-36 protein, heat shock protein and retinal antigens have been associated with pars planitis (PP), but their participation in the development of the disease are unknown. A search for ...new molecules related to PP is necessary. This work focused on the identification of peptides recognized by PP patient sera using the phage display method.
Sera of PP patients were used to isolate peptides fused to M13-phage pIII protein. The response of PP and healthy sera to peptides was determined by ELISA. PCR amplification and sequencing of peptide-encoding fragments from clones with high recognition by PP sera were used to characterize displayed peptides.
One hundred clones were randomly selected from a phage display library after three panning rounds using serum proteins from a PP patient. The immunologic response level of 100 clones selected were determined with a major number of patients, it was found that one clone was recognized stronger in PP patients sera than in healthy sera (PP vs. healthy; P < 0.05). The peptide-encoding region of this clone was sequenced and translated. The peptide sequence corresponded to HSEAETGPP. An identical amino acid sequence to HSEAETGPP is found in the human proline-rich transmembrane protein 2 which has not been related with eye diseases.
These results suggest that the peptide HSEAETGPP is associated with PP.
Extracellular vesicles (EVs) are evaginations of the cytoplasmic membrane, containing nucleic acids, proteins, lipids, enzymes, and toxins. EVs participate in various bacterial physiological ...processes.
interacts and communicates with the host skin.
EVs may have an essential role in this communication mechanism, modulating the immunological environment. This work aimed to evaluate if
EVs can modulate cytokine production by keratinocytes in vitro and in vivo using the imiquimod-induced psoriasis murine model.
EVs were obtained from a commensal strain (ATC12228EVs) and a clinical isolated strain (983EVs). EVs from both origins induced IL-6 expression in HaCaT keratinocyte cultures; nevertheless, 983EVs promoted a higher expression of the pro-inflammatory cytokines VEGF-A, LL37, IL-8, and IL-17F than ATCC12228EVs. Moreover, in vivo imiquimod-induced psoriatic skin treated with ATCC12228EVs reduced the characteristic psoriatic skin features, such as acanthosis and cellular infiltrate, as well as VEGF-A, IL-6, KC, IL-23, IL-17F, IL-36γ, and IL-36R expression in a more efficient manner than 983EVs; however, in contrast, Foxp3 expression did not significantly change, and IL-36 receptor antagonist (IL-36Ra) was found to be increased. Our findings showed a distinctive immunological profile induction that is dependent on the clinical or commensal EV origin in a mice model of skin-like psoriasis. Characteristically, proteomics analysis showed differences in the EVs protein content, dependent on origin of the isolated EVs. Specifically, in ATCC12228EVs, we found the proteins glutamate dehydrogenase, ornithine carbamoyltransferase, arginine deiminase, carbamate kinase, catalase, superoxide dismutase, phenol-soluble β1/β2 modulin, and polyglycerol phosphate α-glucosyltransferase, which could be involved in the reduction of lesions in the murine imiquimod-induced psoriasis skin. Our results show that the commensal ATCC12228EVs have a greater protective/attenuating effect on the murine imiquimod-induced psoriasis by inducing IL-36Ra expression in comparison with EVs from a clinical isolate of
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The viscosity reduction technologies have become a key issue to improve mobility and properties of heavy oils. However, the presence of asphaltenes, resins, metals and sulfur in heavy oil strongly ...infuence the mobility of heavy oil causing serious operational problems in heavy oil production. In the recent years, there have been new developments in heavy oil recovery techniques and one new method is by in-situ catalytic upgrading of heavy oils. Because of their potential applications as an environmentally friendly and catalytically active solvent, ionic liquids have been gradually applied in upgrading of heavy oils. Therefore, this review selects and analyzes some research studies that have been reported in the literature to understand the physical and chemical phenomena involved in heavy oil upgrading by using ionic liquids. Moreover, we present a discussion about the most important variables in the process to provide a signifcant understanding of the ability of ionic liquids to reduce the viscosity.
Las tecnologías de reducción de viscosidad de los crudos pesados se han convertido en un asunto clave para mejorar la movilidad y las propiedades del crudo. Sin embargo, la fuidez de los crudos está fuertemente infuenciada por la presencia de asfaltenos, resinas, metales y azufre, los cuales causan serios problemas operacionales en la producción. En los últimos años, han surgido nuevos avances en las técnicas de recuperación de crudo pesado, y entre ellas se encuentra el mejoramiento catalítico in-situ. Debido a sus posibles aplicaciones como un solvente activo catalíticamente y ambientalmente amigable, los líquidos iónicos han sido aplicados gradualmente en el mejoramiento de crudos pesados. Por tal razón, esta revisión selecciona y analiza algunos estudios de investigación que han sido reportados en la literatura para comprender los fenómenos físicos y químicos involucrados en el mejoramiento de crudos pesados mediante el uso de líquidos iónicos. Además, se presenta una discusión acerca de las variables más importantes en el proceso para proporcionar una comprensión signifcativa de la capacidad de los líquidos iónicos para reducir la viscosidad de los crudos pesados.
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The infection frequency associated to bacterial conjunctivitis, corneal ulcers (CU), and endophthalmitis was studied along a five years period. The isolation and identification of microorganisms were ...performed by culture-based methods and biochemical test respectively. Also, a nested PCR to detect gram-negative and gram-positive bacteria in the clinical samples was assayed. Nested PCR was a more efficient method than culture to detect bacteria in the samples. The most frequently isolated species was Staphylococcus epidermidis, a bacterium commonly considered as a human saprophyte. The S. epidermidis strains from conjunctivitis, CU, and endophthalmitis exhibited 46, 33.9, and 34.1% of oxacilin-resistance respectively. A total of 28% of intermediate-vancomycin resistance (MIC = 8-16 microg/ml) was observed among S. epidermidis strain collection. The UPGMA cluster analysis of the multiresistance profile data of intermediate vancomycin-resistant S. epidermidis strains showed a high phenotypic diversity and no relationship between each group and their clinical origin. The biofilm formation capacity was broadly distributed (66%), particularly among intermediate-vancomycin strains (> 75%). In brief, S. epidermidis displayed a high diversity of antibiotic resistance profiles and biofilm formation capacity. These phenotypic traits could explain the high isolation frequency of S. epidermidis from ocular infections and oblige to review the saprophytic status of these bacteria.
Lógicas colectivas y nuevas formas de politicidad Aranda Bustamante, Gilberto; Asselborn, Carlos Javier; Báez Urbina, Francisco ...
Polis (Santiago, Chile : 2001),
06/2011, Letnik:
10, Številka:
28
Journal Article
Odprti dostop
El número 28 de Revista Polis se abre a la discusión en torno a la “disputa por la construcción democrática” en América Latina, sus sentidos, límites, potencialidades y alternativas, desde la ...perspectiva de subjetividades colectivas, de los movimientos sociales y la acción colectiva. En el marco de los procesos de configuración, estabilización y profundización del orden democrático en América Latina, nos preguntamos: ¿De qué manera participan los actores sociales y las subjetividades colectivas en los procesos de disputa por la construcción democrática? Entendemos que las respuestas a esta interrogante son múltiples y variadas, no sólo porque incluyen diferentes escalas de intervención (del orden nacional a lo barrial, pasando por lo local), diferentes temporalidades de acción (con distintos ritmos y velocidades) o también porque implican diversos actores (y sus diversas maneras de articularse como tales) con sus intereses e imaginarios. No obstante esta pluralidad, partimos de la presunción de que los actores colectivos –insistimos, heterogéneos y plurales- participan de estos procesos implementando una diversidad significativa de lógicas colectivas, incluso contrapuestas entre sí, que afectan la configuración democrática en más de un sentido.
Objectives: Staphylococcus epidermidis can cause prosthetic joint infections. Strategies to differentiate between healthy skin and prosthetic joint infections isolates are relatively ineffective, ...which makes necessary to search for new differential biomarkers. Staphylococcus epidermidis has eleven surface proteins, denoted as Ses proteins. In this work, ses genes are used as biomarkers to differentiate between prosthetic joint infections and healthy skin isolates.
Methods: All prosthetic joint infections (n = 51) and healthy skin (n = 51) isolates were genotyped by pulsed-field gel electrophoresis. icaA, embp, sesA-I, and sdrF genes were determined by PCR. The phenotypic data included biofilm production and antibiotic resistance.
Results: 10 pulsed-field gel electrophoresis profiles were identified: four profiles were exclusive of prosthetic joint infections isolates, three profiles presented a higher proportion in prosthetic joint infections isolates and three profiles presented a higher proportion in healthy skin isolates. sesA, sesB, sesC, sesD, sesE, sesG, and sesH genes were more prevalent in healthy skin isolates than in prosthetic joint infections isolates (p < .05). Prosthetic joint infections isolates were more resistant to oxacillin (78%), ciprofloxacin (60%), levofloxacin (60%), and moxifloxacin (57%). The principal coordinate analysis and a discriminant analysis found that prosthetic joint infections isolates had as discriminant biomarker the biofilm formation, the icaA gene, oxacillin, ciprofloxacin, levofloxacin, moxifloxacin, and gentamicin resistance. In contrast, the healthy skin isolates had as discriminant biomarkers the embp, sesA, sesB, sesC, sesD, sesE, sesG, and sesH genes.
Conclusions: These data suggest that ses genes can be considered biomarkers to differentiate between S. epidermidis commensal and prosthetic joint infections clinical.
There is an increased interest for finding strains able to contribute to plant nutrition and health, since these are desirable for the formulation of agricultural bioinoculants. Obtaining a safe and ...efficient product requires exhaustive evaluations from which most methods used for this purpose involve the use of substrates or are established under uncontrolled conditions, so that various factors can mask the results of the plant-microorganism interaction. In vitro methods mostly involve the use of Petri Dishes (PD) but limit the results to seed germination. Other methods of germination involve the use of acrylic boxes (GB) allowing for better plant development, but are little known. Methods such as ISTA are widely used to evaluate the physiological quality of seeds in productive terms. Despite their efficiency, these methods have not been previously used to evaluate the effect of plant-microorganism interaction on crops. In the present study, modifications were made to the germination between paper of ISTA (BP) method, and were compared to the PD anf GB methods to evaluate the impact of the bacterium Serratia liquefaciens 385 and the yeast Clavispora lusitaniae Y35 on maize, bean and squash. Through the evaluation of physiological parameters in seed and seedling, the results clearly showed the superiority of the BP method to evaluate the effect of microorganisms since it allows observing a better development in the seedlings in terms of growth of the plumule, a better architecture of the radical system in which the emergence of adventitious secondary roots and differentiated radical hairs is observed in comparison with seedlings obtained under the other methods. Similarly, it was possible to observe the different effects on each of the three crops with respect to the inoculation of the bacteria and yeast. These results were significantly better in seedlings obtained in the BP method independently of the type of crop evaluated, considering the BP method suitable to be applied in large-scale bioprospecting plant-growth-promoting microorganism studies.
•Fast and simple evaluations of plant growth-promoting microbial strains on plants.•Large-scale bioprospecting studies of microbial strains to develop bioinoculants.•Between paper ISTA germination method show significantly better results despite the seed crop.
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