Characterization of the microbiota associated to Pecten maximus gonads using 454-pyrosequencing

A next-generation sequencing (NGS) approach was used to study the microbiota associated to Pecten maximus broodstock, applying pyrosequencing of PCR-amplified V1-V4 16S rRNA gene regions. We analysed the resident bacterial communities in female and male scallop gonads before and after spawning. DNA samples were amplified and quality-filtered reads were assigned to family and genus taxonomic levels using the Ribosomal Database Project classifier. A total of 18,520 sequences were detected, belonging to 13 phyla, including Proteobacteria (55%), Bacteroidetes (11,7%), Firmicutes (3%), Actinobacteria (2%) and Spirochaetes (1,2%), and 110 genera. The major fraction of the sequences detected corresponded to Proteobacteria, Beta- and Gammaprotebacteria being the most abundant classes. The microbiota of P. maximus gonad harbour a wide diversity, however differences on male and female samples were observed, where female gonad samples show a larger number of genera and families. The dominant bacterial genera appeared to be Delftia, Acinetobacter, Hydrotalea, Aquabacterium, Bacillus, Sediminibacterium, Sphingomonas, and Pseudomonas that were present among the four analysed samples. This next generation sequencing technique, applied for the first time in P. maximus (great scallop) gonads was useful for the study of the bacterial communities in this mollusc, unravelling the great bacterial diversity in its microbiota. [Int Microbiol 19(2): 93-99(2016)]Keywords: Pecten maximus · gonads microbiota · next-generation sequencing (NGS) · molluscs pathogens · aquacultur

Predicting Adverse Events beyond Stroke and Bleeding with the ABC-Stroke and ABC-Bleeding Scores in Patients with Atrial Fibrillation: The Murcia AF Project

Background The ABC (age, biomarkers, and clinical history)-stroke and ABC-bleeding are biomarker-based scores proposed to predict stroke and bleeding, but non-specificity of biomarkers is common, predicting different clinical events at the same time. We assessed the predictive performance of the ABC-stroke and ABC-bleeding scores, for outcomes beyond ischemic stroke and major bleeding, in a cohort of atrial fibrillation (AF) patients. Methods We included AF patients stable on vitamin K antagonists for 6 months. The ABC-stroke and ABC-bleeding were calculated and the predictive values for myocardial infarction (MI), acute heart failure (HF), a composite of cardiovascular events, and all-cause deaths were compared. Results We included 1,044 patients (49.2% male; median age 76 [71–81] years). During 6.5 (4.3–7.9) years, there were 58 (5.6%) MIs, 98 (9.4%) acute HFs, 167 (16%) cardiovascular events, and 418 (40%) all-cause deaths. There were no differences in mean ABC-stroke and ABC-bleeding scores in patients with/without MI (p = 0.367 and p = 0.286, respectively); both scores were higher in patients with acute HF, cardiovascular events, or death (all p  0.70). Clinical usefulness whether assessed by ABC-stroke or ABC-bleeding was similar for various primary endpoints. Conclusion In AF patients, the ABC-stroke and ABC-bleeding scores demonstrated similar predictive ability for outcomes beyond stroke and bleeding, including MI, acute HF, a composite of cardiovascular events, and all-cause deaths. This is consistent with nonspecificity of biomarkers that predict “sick” patients or poor prognosis overall

Nasopharyngeal Microbiota in Children With Invasive Pneumococcal Disease: Identification of Bacteria With Potential Disease-Promoting and Protective Effects

Background and Aims: The risk of suffering from some infectious diseases can be related to specific microbiota profiles. Specifically, the nasopharyngeal microbiota could play a role as a risk or protective factor in the development of invasive disease caused by S. pneumoniae.Methodology: We analyzed the nasopharyngeal microbiota of children with invasive pneumococcal disease (IPD) and that of healthy controls matched by age, sex, and seasonality from Catalonia, Spain. Epidemiological, microbiological and clinical variables were considered to compare microbiota profiles, analyzed by sequencing the V1–V4 region of the 16S rRNA gene.Results: Twenty-eight children with IPD (median age 43 months) and 28 controls (42.6 months) were included in the study. IPD children presented a significantly higher bacterial diversity and richness (p < 0.001). Principal coordinate analysis revealed three different microbiota profiles: microbiota A, dominated by the genus Dolosigranulum (44.3%); Microbiota B, mostly represented by Streptococcus (36.9%) and Staphylococcus (21.3%) and a high diversity of anaerobic genera including Veillonella, Prevotella and Porphyromonas; and Microbiota C, mainly containing Haemophilus (52.1%) and Moraxella (31.4%). The only explanatory factor for the three microbiotas was the classification of children into disease or healthy controls (p = 0.006). A significant negative correlation was found between Dolosigranulum vs. Streptococcus (p = 0.029), suggesting a potential antagonistic effect against pneumococcal pathogens.Conclusions: The higher bacterial diversity and richness in children with IPD could suggest an impaired immune response. This lack of immune competence could be aggravated by breastfeeding <6 months and by the presence of keystone pathogens such as Porphyromonas, a bacterium which has been shown to be able to manipulate the immune response, and that could favor the overgrowth of many proteolytic anaerobic organisms giving rise to a dramatic dysbiosis. From an applied viewpoint, we found suggestive microbiota profiles associated to IPD or asymptomatic colonization that could be used as disease biomarkers or to pave the way for characterizing health-associated inhabitants of the respiratory tract. The identification of beneficial bacteria could be useful to prevent pneumococcal infections by integrating those microorganisms in a probiotic formula. The present study suggests not only respiratory tract samples, but also breast milk, as a potential source of those beneficial bacteria

Integral approach using bacterial microbiome to stabilize municipal solid waste

Biological transformation of municipal solid waste is an environment-friendly management strategy against recalcitrant residues. The bacterial biome that inhabit said residues are responsible of decomposing both simple and complex materials. For this reason, processes such as composting, which favor the acceleration of the transformation of organic matter, can contribute to the degradation of municipal solid waste. Not only as mere fertilizer for crops, but also as methods for the recovery of solid waste. However, the control of the conditions necessary to achieve an optimal process on an industrial scale is a great concern. Thus, the aim of this work focuses on the characterization of the bacterial microbiome on three municipal solid waste facilities in order to deepen the role of microorganisms in the state of the final product obtained. For it, an intensive metagenomic analysis as well as a battery of physicochemical determinations were carried out. The lack of adequate thermophilic phases was decisive in finding certain bacterial genera, such as Lactobacillus, which was significant through these processes. Biodiversity did not follow a common pattern in the three processes, neither in abundance nor in richness but, in general, it was greater during the bio-oxidative stage. Despite the different trend in terms of the degradation of carbon fractions in these wastes, at the end of the biodegradation treatments, a sufficient degree of bioestabilization of the organic matter was reached. The results offer the opportunity to obtain a level of detail unprecedented of the structure, dynamics and function of the bacterial community in real conditions, without the control offered by laboratory conditions or pilot plants

Caracterización de cepas con potencial probiótico anti-caries

[EN] Dental caries is a disease produced by the demineralization of enamel as a consequence of the acid produced by micro-organisms. Although several acidogenic bacteria have been shown to be related to caries development, there is important evidence that so called mutans streptococci are some of the key cariogenic agents in humans. For this reason, several preventive strategies have been developed in the last years, ranging from active and passive immunization to the use of mouth rinses or probiotics. In that sense, the Oral Microbiome Laboratory at the CSISP has isolated colonies from a new Streptococcus species from dental plaque of individuals that have never suffered from caries and that has an inhibitory effect over mutans streptococci. The current thesis aims to characterize phenotypically and genetically strains 7746 and 7747 of the new species S. anticariensis in order to determine their appropriateness for the development of an anti-caries probiotic. Thus, I performed microscopic, biochemical, genomic and growth tests, determining the following characteristics: 1) They are Gram-positive cocci, facultative anaerobes, catalase- and oxidase-negative; 2) Biochemically, they are characterized by being alkaline phosphatase-, leucine aminopeptidase-, maltose- and lactosepositive; 3) They are mesophilic and with an optimal pH range of 6,0-7,5; 4) They grow on milk, and the growth medium showing a higher bacterial load is TSB supplemented with 0.1% yeast extract; 5) The inhibitory effect of S.anticariensis sp.nov against S. mutans is produced only at stationary phase, being the fraction of the supernatant lower than 3 kDa that with the highest activity; 6) S. anticariensis sp. Nov is part od the normal commensal microbiota of 118 healthy individuals studied; 7) The genomes of the two strains do not show genes coding for toxins, virulence factors or mobile elements that may compromise their safety; 8) They are sensitive to different kinds of antibiotics, including 3rdgeneration cephalosporins, beta-lactamics, macrolides, synthetic and semisynthetic ones. In general, the results of the current thesis support that strains 7746 and 7747 are adequate for their use as potential probiotics, that could be used in a functional food, as it complies with the basic safety and growth requirements to be administered in humans, showing in vitro the desired beneficial effect.[ES] La caries es una enfermedad causada por la desmineralización del diente a consecuencia d producido por microorganismos. Aunque varias bacterias acidogénicas han sido relacionada desarrollo de caries, existe evidencia notoria de que los Streptococcus del grupo mutans son un agentes cariogénicos clave en humanos. Por este motivo, diversas estrategias de prevención venido desarrollando en los últimos años, desde herramientas de inmunización activa y pasiva enjuagues bucales o probióticos. En este sentido, el Laboratorio del Microbioma Humano de aisló colonias de una nueva especie de Streptococcus procedente de la placa dental de in adultos que nunca habían sufrido caries, y que tiene un efecto inhibidor sobre Streptococcus d mutans. La presente tesis pretende la caracterización fenotípica y genotípica de las cepas 7746 de la nueva especie S. anticariensis con el fin de determinar su adecuación para el desarroll probiótico anti-caries. Para ello, se realizaron pruebas microscópicas, bioquímicas, de creci genómicas, determinando las siguientes características de las cepas estudiadas: 1) Son coco positivos, anaerobios facultativos, catalasa y oxidasa negativos; 2) Bioquímicamente, se cara por ser fosfatasa alcalina, leucina aminopeptidasa, maltosa y lactosa positivos; 3) Son b mesófilas y con un pH óptimo de crecimiento entre 6,0 y 7,5; 4) Crecen de forma adecuada en el medio de cultivo que permite obtener una mayor cantidad de masa celular es el cald tripticaseína suplementado con extracto de levadura al 0,1%; 5) El efecto inhibidor de S.antic sp.nov frente a S. mutans es producido cuando las cepas llegan a fase estacionaria, siendo la de sobrenadante menor a 3 kDa la que demuestra mayor actividad; 6) S. anticariensis sp. nov de la flora comensal de 118 individuos sanos estudiados; 7) En los genomas de las cepas no se genes de virulencia, toxinas, ni presencia de elementos móviles que comprometan la segurida mismas; 8) Son sensibles a varios tipos de antibióticos, que incluyen los denominados de espectro, cefalosporinas de tercera generación, beta-lactámicos, macrólidos, sintéticos y semisi Los resultados de la presente tesis apoyan que las cepas 7746 y 7747 son adecuadas para su u posible probiótico, que pueda ser incluido en un alimento funcional, enjuague bucal u otra administración en humanos, ya que cumple con las condiciones básicas de seguridad para p suministrado y produciendo el efecto beneficioso preventivo deseado in vitro.Camelo Castillo, AJ. (2013). Caracterización de cepas con potencial probiótico anti-caries. http://hdl.handle.net/10251/4337

Desarrollo de Streptococcus dentisani sp. nov, como probiótico para la salud bucodental

Las enfermedades orales como la caries se encuentran entre las más prevalentes en todo el mundo y se desarrollan como consecuencia de una disbiosis microbiana. Probablemente por esta naturaleza polimicrobiana y altamente variable, las aproximaciones de inmunización no son efectivas, y el uso de pre y probióticos que restablezcan la homeostasis han sido propuestas como alternativas prometedoras. Durante años se han probado varias cepas bacterianas como posibles organismos promotores de la salud oral, pero generalmente son especies aisladas de nichos distintos al sitio donde deben ejercer su acción probiótica final, típicamente de muestras fecales. Nuestra hipótesis defiende que los comensales orales asociados a condiciones de salud serán más efectivos que las especies probióticas tradicionales asociadas a intestino, en un aspecto tan clave como la colonización del nicho dental. Además, el usar cepas propias de la cavidad oral ayudaría a solventar problemas prácticos, como la seguridad, la toxicidad de las cepas y el establecimiento de las dosis adecuadas para su administración. En la presente tesis, se han realizado estudios genómicos, taxonómicos y bioquímicos en dos cepas de estreptococos aisladas de placa dental en individuos sin antecedentes de caries dental. Mediante análisis de los genes 16S, 23S y sodA y los valores de Identidad Nucleotídica Promedio (ANI), se demostró que estas cepas pertenecían al grupo mitis, pero ambas se agrupaban en una nueva rama filogenética, proponiendo para estos aislados el nombre de Streptococcus dentisani sp. nov. La especie propuesta es detectada en el 98% de las muestras de placa dental de individuos sanos en niveles de 10^8 bacterias totales en placa supragingival y, tras experimentos in vivo e in vitro en las cepas 7746 y 7747, se pudo comprobar que no produce ningún metabolito secundario tóxico, no presenta genes de virulencia ni presencia de elementos móviles en su genoma, no sobreviven a una digestión estomacal en simulador in vitro, y experimentalmente no presentan resistencia frente a los antibióticos comúnmente usados en clínica, lo que evita posibles efectos secundarios. Además, pudimos demostrar que esta especie tiene una doble acción beneficiosa, ya que inhibe el crecimiento de los principales patógenos orales a través de la producción de al menos seis bacteriocinas, y también amortigua el pH ácido (la causa principal de la caries dental) a través de la vía arginolítica, que activa en presencia de arginina y en condiciones de pH ácido para producir amonio. Por todo ello, proponemos el uso de S. dentisani como un probiótico prometedor para la mejora de la salud bucodental, cuya eficacia deberá probarse en ensayos clínicos en seres humanos

Gut Microbiota and the Quality of Oral Anticoagulation in Vitamin K Antagonists Users: A Review of Potential Implications

The efficacy and safety of vitamin K antagonists (VKAs) as oral anticoagulants (OACs) depend on the quality of anticoagulation control, as reflected by the mean time in therapeutic range (TTR). Several factors may be involved in poor TTR such as comorbidities, high inter-individual variability, interacting drugs, and non-adherence. Recent studies suggest that gut microbiota (GM) plays an important role in the pathogenesis of cardiovascular diseases, but the effect of the GM on anticoagulation control with VKAs is unknown. In the present review article, we propose different mechanisms by which the GM could have an impact on the quality of anticoagulation control in patients taking VKA therapy. We suggest that the potential effects of GM may be mediated first, by an indirect effect of metabolites produced by GM in the availability of VKAs drugs; second, by an effect of vitamin K-producing bacteria; and finally, by the structural modification of the molecules of VKAs. Future research will help confirm these hypotheses and may suggest profiles of bacterial signatures or microbial metabolites, to be used as biomarkers to predict the quality of anticoagulation. This could lead to the design of intervention strategies modulating gut microbiota, for example, by using probiotics

Treatment strategies for patients with atrial fibrillation and anticoagulant-associated intracranial hemorrhage: an overview of the pharmacotherapy

Introduction Oral anticoagulants (OAC) reduce stroke/systemic embolism and mortality risks in atrial fibrillation (AF). However, there is an inherent bleeding risk with OAC, where intracranial hemorrhage (ICH) is the most feared, disabling, and lethal complication of this therapy. Therefore, the optimal management of OAC-associated ICH is not well defined despite multiple suggested strategies. Areas covered In this review, the authors describe the severity and risk factors for OAC-associated ICH and the associated implications for using DOACs in AF patients. We also provide an overview of the management of OAC-associated ICH and treatment reversal strategies, including specific and nonspecific reversal agents as well as a comprehensive summary of the evidence about the resumption of DOAC and the optimal timing

Antithrombotic Therapy in Patients with Peripheral Artery Disease: A Focused Review on Oral Anticoagulation

Peripheral artery disease (PAD) is a major cause of morbidity and mortality but it is usually underdiagnosed and undertreated. Patients with PAD present dysregulated procoagulant, anticoagulant, and fibrinolytic pathways leading to arterial and venous thrombosis. The risk of several ischemic-related complications could be mitigated with appropriate antithrombotic therapy, which plays a central role in all types of PAD. For years, antiplatelets have been indicated in patients with symptomatic PAD or those who have undergone revascularization. Unfortunately, a non-negligible proportion of patients with PAD will suffer from adverse events during the follow-up, even despite proper medical therapies for the prevention of PAD complications. Thus, there is room for improving clinical outcomes in these patients. Given the implication of both, primary and secondary hemostasis in arterial thrombosis and the pathophysiology of PAD, the combination of antiplatelets and anticoagulants has emerged as a potential antithrombotic alternative to antiplatelets alone. In this narrative review article, we have highlighted the most recent evidence about antithrombotic therapy in PAD patients, with a special focus on oral anticoagulation. Certainly, COMPASS and VOYAGER PAD trials have shown promising results. Thus, rivaroxaban in combination with aspirin seem to reduce cardiovascular outcomes with a similar bleeding risk compared to aspirin alone. Nevertheless, results from real-world studies are needed to confirm these observations, and other trials will provide novel evidence about the safety and efficacy of emerging anticoagulant agents