La bioprecipitación de carbonato de calcio por la biota nativa como un método de restauración.

A selection of 30 previously isolated bacteria of different types were taken, mainly Bacillus, which had been previously identified by microbiological and molecular methods to be epilithic biofilms from Chapultepec's Castle in Mexico City, DF. Different methodologies were practiced to determine which of them were forming biofilms and their quantification, the ureasa test and the production of crystals of calcium carbonate in Petry plate with Luria Bertani enriched with calcium carbonate to 0.2 %. The crystals obtained were submitted to diffraction of X-rays and Electronic Microscopy of Sweep. The results show that all microorganisms tested were involved in the process of biofilm formation, and only 12 isolates, including the IS16 (Bacillus subtilis); IIS15a (Bacillus cereus) and IIIS10 (Bacillus subtilis) strains, were the best biofilm formers with high UFC / mL, good in terms of bioprecipitation of carbonates. Particularly, the strains IIIS4 (Bacillus megaterium), IS5 (Bacillus subtilis), IIIS9b (Bacillus subtilis), 21 (Pantoea agglomerans) and IIIS5 (Bacillus simplex). May be some of the microorganisms could be capable of producing urease, to induce precipitation of calcite that contributes to the restoration. As of now, little is known about the participation of Pantoea agglomerans in processes of biorrestauration by means of bioprecipitation of crystals of calcium carbonate and due to the fact that a good response was obtained from the test of ureasa and the crystals obtained were mainly Calcita (99 %), this work shows the feasibility of using this native microorganisms for their activation to achieve the restoration of the worn monuments.Partiendo de 30 aislados bacterianos de diferentes tipos (fundamentalmente Bacillus), previamente aislados e identificados por métodos microbiológicos y moleculares, provenientes de biopelículas epilíticas traídas del Castillo de Chapultepec de la ciudad de México, DF. Se realizaron diferentes metodologías como comprobación y determinación de formación biopelículas y su cuantificación, prueba de ureasa y la producción de cristales de carbonato de calcio en placa Petry con LB enriquecido con carbonato de calcio al 0.2 %. Los cristales fueron enviados a difracción de rayos X y Microscopia Electrónica de Barrido.Los resultados muestran que en alguna medida todos los microorganismos probados  participan en el proceso de formación de biopelículas y un total de 12 aislados destacaron como los mejores formadores de biopelículas, sobresaliendo las cepas IS16 y IIIS10 (Bacillus subtilis), IIS15a (Bacillus cereus) por ser las que mayores UFC/mL presentaron en la biopelícula. Todos los buenos formadores de biopelículas resultan también adecuados en cuanto a bioprecipitación de carbonatos, destacando las cepas IIIS4 (Bacillus megaterium), IS5 (Bacillus subtilis) e IIIS9b (Bacillus subtilis), 21 (Pantoea agglomerans) y la IIIS5 (Bacillus simplex). Poco o nada se sabe hasta el momento de la participación de Pantoea agglomerans en procesos de biorrestauración mediante bioprecipitación de cristales de carbonato de calcio y debido a que se obtuvo buena respuesta a la prueba de ureasa y los cristales obtenidos fueron mayormente Calcita (99 %), este trabajo muestra la factibilidad de usar la biota nativa para su activación y así lograr la restauración de los monumentos biodeteriorados

Culturable fungi associated with urban stone surfaces in Mexico City

Background: Urban surface stones in Mexico City are exposed to a temperate climate and a range of atmospheric conditions ranging from mildly impacted to heavily polluted areas. In this study, we focused on the characterization of the cultivable fungal component of selected biological patinas in the surrounding area of Chapultepec castle, a historic monument in Mexico City. Thirty four representative fungal isolates selected based on distinctive differential macroscopic characteristics out of a total of 300 fungi, were characterized using morphological and molecular approaches. Results: This identification strategy based on the combination of phenotypic- and molecular-based methodologies allowed us to discriminate the fungal community in some cases down to the species level. Conclusions: The characterization of this mycoflora revealed the presence of a complex fungal community mainly represented by filamentous fungi belonging to the genera Fusarium , Trichoderma , Aspergillus , Cladosporium , Alternaria , Mucor , Penicillium , Pestalotiopsis , and the dimorphic fungus Aureobasidium , along with the yeast Rhodotorula . A specific distribution of fungi could be observed based on the type of biological patina analyzed

Cambios en la composición de la comunidad fúngica de biopelículas sobre roca calcárea a través de una cronosecuencia en Campeche, México

Background and Aims: The colonization of lithic substrates by fungal communities is determined by the properties of the substrate (bioreceptivity) and climatic and microclimatic conditions. However, the effect of the exposure time of the limestone surface to the environment on fungal communities has not been extensively investigated. In this study, we analyze the composition and structure of fungal communities occurring in biofilms on limestone walls of modern edifications constructed at different times in a subtropical environment in Campeche, Mexico.Methods: A chronosequence of walls built one, five and 10 years ago was considered. On each wall, three surface areas of 3 × 3 cm of the corresponding biofilm were scraped for subsequent analysis. Fungi were isolated by washing and particle filtration technique and were then inoculated in two contrasting culture media (oligotrophic and copiotrophic). The fungi were identified according to macro and microscopic characteristics.Key results: We found 73 genera and 202 species from 844 isolates. Our results showed that fungal communities differed in each biofilm. In the middle-aged biofilm a high number of isolates was found, but both species richness and diversity were low. In contrast, in the old biofilm species richness and diversity were high; Hyphomycete 1, Myrothecium roridum and Pestalotiopsis maculans were abundant. The dominant species in the middle-aged biofilm were Curvularia lunata, Curvularia pallescens, Fusarium oxysporum and Fusarium redolens, and in the young biofilm were Cladosporium cladosporioides, Curvularia clavata, Paraconiothyrium sp. and Phoma eupyrena.Conclusions: Our results suggest that the composition of the fungal community in each biofilm varies according to time of exposure to the environment. Furthermore, the fungal community was composed of a pool of uncommon species that might be autochthonous to limestone.Antecedentes y Objetivos: La colonización de los sustratos líticos por comunidades fúngicas está determinada por las propiedades del sustrato (bioreceptividad) y las condiciones climáticas y microclimáticas. Sin embargo, los efectos del tiempo de exposición de la superficie de la roca calcárea al ambiente sobre la composición de las comunidades fúngicas no se ha investigado. En este estudio, analizamos la composición y estructura de las comunidades fúngicas inmersas en biopelículas asociadas a roca calcárea, en paredes de edificaciones modernas construidas a diferentes tiempos en un ambiente subtropical en Campeche, México.Métodos: Se consideró una cronosecuencia de paredes construidas a uno, cinco y 10 años. Sobre cada pared, se rasparon tres superficies de 3 × 3 cm para cada biopelícula. Los hongos se aislaron por la técnica de lavado y filtración de partículas, posteriormente se inocularon en dos medios de cultivo contrastantes (un medio oligotrófico y uno copiotrófico). Los hongos se identificaron de acuerdo a sus características macro y microscópicas.Resultados clave: Encontramos 73 géneros y 202 especies de 844 aislados. Los resultados mostraron que las comunidades fúngicas son diferentes en las tres biopelículas. En la biopelícula de desarrollo intermedio encontramos un alto número de aislados, pero tanto la riqueza como la diversidad fueron bajas. En contraste, en la biopelícula avanzada, los valores de riqueza de especies y diversidad fueron altos, y las especies abundantes fueron Hyphomycete 1, Myrothecium roridum y Pestalotiopsis maculans. Las especies dominantes en la biopelícula intermedia fueron Curvularia lunata, Curvularia pallescens, Fusarium oxysporum y Fusarium redolens, y en la biopelícula joven fueron Cladosporium cladosporioides, Curvularia clavata, Paraconiothyrium sp. y Phoma eupyrena.Conclusiones: Nuestros resultados sugieren que la composición de la comunidad fúngica en cada biopelícula cambia de acuerdo al tiempo de exposición de la roca calcárea al ambiente. Además, como parte de la composición de la comunidad fúngica, encontramos un conjunto de especies poco comunes que podrían ser autóctonas en la roca calcárea

Global burden of 369 diseases and injuries in 204 countries and territories, 1990–2019: a systematic analysis for the Global Burden of Disease Study 2019

Background: In an era of shifting global agendas and expanded emphasis on non-communicable diseases and injuries along with communicable diseases, sound evidence on trends by cause at the national level is essential. The Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) provides a systematic scientific assessment of published, publicly available, and contributed data on incidence, prevalence, and mortality for a mutually exclusive and collectively exhaustive list of diseases and injuries. Methods: GBD estimates incidence, prevalence, mortality, years of life lost (YLLs), years lived with disability (YLDs), and disability-adjusted life-years (DALYs) due to 369 diseases and injuries, for two sexes, and for 204 countries and territories. Input data were extracted from censuses, household surveys, civil registration and vital statistics, disease registries, health service use, air pollution monitors, satellite imaging, disease notifications, and other sources. Cause-specific death rates and cause fractions were calculated using the Cause of Death Ensemble model and spatiotemporal Gaussian process regression. Cause-specific deaths were adjusted to match the total all-cause deaths calculated as part of the GBD population, fertility, and mortality estimates. Deaths were multiplied by standard life expectancy at each age to calculate YLLs. A Bayesian meta-regression modelling tool, DisMod-MR 2.1, was used to ensure consistency between incidence, prevalence, remission, excess mortality, and cause-specific mortality for most causes. Prevalence estimates were multiplied by disability weights for mutually exclusive sequelae of diseases and injuries to calculate YLDs. We considered results in the context of the Socio-demographic Index (SDI), a composite indicator of income per capita, years of schooling, and fertility rate in females younger than 25 years. Uncertainty intervals (UIs) were generated for every metric using the 25th and 975th ordered 1000 draw values of the posterior distribution. Findings: Global health has steadily improved over the past 30 years as measured by age-standardised DALY rates. After taking into account population growth and ageing, the absolute number of DALYs has remained stable. Since 2010, the pace of decline in global age-standardised DALY rates has accelerated in age groups younger than 50 years compared with the 1990–2010 time period, with the greatest annualised rate of decline occurring in the 0–9-year age group. Six infectious diseases were among the top ten causes of DALYs in children younger than 10 years in 2019: lower respiratory infections (ranked second), diarrhoeal diseases (third), malaria (fifth), meningitis (sixth), whooping cough (ninth), and sexually transmitted infections (which, in this age group, is fully accounted for by congenital syphilis; ranked tenth). In adolescents aged 10–24 years, three injury causes were among the top causes of DALYs: road injuries (ranked first), self-harm (third), and interpersonal violence (fifth). Five of the causes that were in the top ten for ages 10–24 years were also in the top ten in the 25–49-year age group: road injuries (ranked first), HIV/AIDS (second), low back pain (fourth), headache disorders (fifth), and depressive disorders (sixth). In 2019, ischaemic heart disease and stroke were the top-ranked causes of DALYs in both the 50–74-year and 75-years-and-older age groups. Since 1990, there has been a marked shift towards a greater proportion of burden due to YLDs from non-communicable diseases and injuries. In 2019, there were 11 countries where non-communicable disease and injury YLDs constituted more than half of all disease burden. Decreases in age-standardised DALY rates have accelerated over the past decade in countries at the lower end of the SDI range, while improvements have started to stagnate or even reverse in countries with higher SDI. Interpretation: As disability becomes an increasingly large component of disease burden and a larger component of health expenditure, greater research and developm nt investment is needed to identify new, more effective intervention strategies. With a rapidly ageing global population, the demands on health services to deal with disabling outcomes, which increase with age, will require policy makers to anticipate these changes. The mix of universal and more geographically specific influences on health reinforces the need for regular reporting on population health in detail and by underlying cause to help decision makers to identify success stories of disease control to emulate, as well as opportunities to improve. Funding: Bill & Melinda Gates Foundation. © 2020 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 licens

Mortality from gastrointestinal congenital anomalies at 264 hospitals in 74 low-income, middle-income, and high-income countries: a multicentre, international, prospective cohort study

Summary Background Congenital anomalies are the fifth leading cause of mortality in children younger than 5 years globally. Many gastrointestinal congenital anomalies are fatal without timely access to neonatal surgical care, but few studies have been done on these conditions in low-income and middle-income countries (LMICs). We compared outcomes of the seven most common gastrointestinal congenital anomalies in low-income, middle-income, and high-income countries globally, and identified factors associated with mortality. Methods We did a multicentre, international prospective cohort study of patients younger than 16 years, presenting to hospital for the first time with oesophageal atresia, congenital diaphragmatic hernia, intestinal atresia, gastroschisis, exomphalos, anorectal malformation, and Hirschsprung’s disease. Recruitment was of consecutive patients for a minimum of 1 month between October, 2018, and April, 2019. We collected data on patient demographics, clinical status, interventions, and outcomes using the REDCap platform. Patients were followed up for 30 days after primary intervention, or 30 days after admission if they did not receive an intervention. The primary outcome was all-cause, in-hospital mortality for all conditions combined and each condition individually, stratified by country income status. We did a complete case analysis. Findings We included 3849 patients with 3975 study conditions (560 with oesophageal atresia, 448 with congenital diaphragmatic hernia, 681 with intestinal atresia, 453 with gastroschisis, 325 with exomphalos, 991 with anorectal malformation, and 517 with Hirschsprung’s disease) from 264 hospitals (89 in high-income countries, 166 in middleincome countries, and nine in low-income countries) in 74 countries. Of the 3849 patients, 2231 (58·0%) were male. Median gestational age at birth was 38 weeks (IQR 36–39) and median bodyweight at presentation was 2·8 kg (2·3–3·3). Mortality among all patients was 37 (39·8%) of 93 in low-income countries, 583 (20·4%) of 2860 in middle-income countries, and 50 (5·6%) of 896 in high-income countries (p<0·0001 between all country income groups). Gastroschisis had the greatest difference in mortality between country income strata (nine [90·0%] of ten in lowincome countries, 97 [31·9%] of 304 in middle-income countries, and two [1·4%] of 139 in high-income countries; p≤0·0001 between all country income groups). Factors significantly associated with higher mortality for all patients combined included country income status (low-income vs high-income countries, risk ratio 2·78 [95% CI 1·88–4·11], p<0·0001; middle-income vs high-income countries, 2·11 [1·59–2·79], p<0·0001), sepsis at presentation (1·20 [1·04–1·40], p=0·016), higher American Society of Anesthesiologists (ASA) score at primary intervention (ASA 4–5 vs ASA 1–2, 1·82 [1·40–2·35], p<0·0001; ASA 3 vs ASA 1–2, 1·58, [1·30–1·92], p<0·0001]), surgical safety checklist not used (1·39 [1·02–1·90], p=0·035), and ventilation or parenteral nutrition unavailable when needed (ventilation 1·96, [1·41–2·71], p=0·0001; parenteral nutrition 1·35, [1·05–1·74], p=0·018). Administration of parenteral nutrition (0·61, [0·47–0·79], p=0·0002) and use of a peripherally inserted central catheter (0·65 [0·50–0·86], p=0·0024) or percutaneous central line (0·69 [0·48–1·00], p=0·049) were associated with lower mortality. Interpretation Unacceptable differences in mortality exist for gastrointestinal congenital anomalies between lowincome, middle-income, and high-income countries. Improving access to quality neonatal surgical care in LMICs will be vital to achieve Sustainable Development Goal 3.2 of ending preventable deaths in neonates and children younger than 5 years by 2030

Магистерская диссертация

A selection of 30 previously isolated bacteria of different types were taken, mainly Bacillus, which had been previously identified by microbiological and molecular methods to be epilithic biofilms from Chapultepec's Castle in Mexico City, DF. Different methodologies were practiced to determine which of them were forming biofilms and their quantification, the ureasa test and the production of crystals of calcium carbonate in Petry plate with Luria Bertani enriched with calcium carbonate to 0.2 %. The crystals obtained were submitted to diffraction of X-rays and Electronic Microscopy of Sweep. The results show that all microorganisms tested were involved in the process of biofilm formation, and only 12 isolates, including the IS16 (Bacillus subtilis); IIS15a (Bacillus cereus) and IIIS10 (Bacillus subtilis) strains, were the best biofilm formers with high UFC / mL, good in terms of bioprecipitation of carbonates. Particularly, the strains IIIS4 (Bacillus megaterium), IS5 (Bacillus subtilis), IIIS9b (Bacillus subtilis), 21 (Pantoea agglomerans) and IIIS5 (Bacillus simplex). May be some of the microorganisms could be capable of producing urease, to induce precipitation of calcite that contributes to the restoration. As of now, little is known about the participation of Pantoea agglomerans in processes of biorrestauration by means of bioprecipitation of crystals of calcium carbonate and due to the fact that a good response was obtained from the test of ureasa and the crystals obtained were mainly Calcita (99 %), this work shows the feasibility of using this native microorganisms for their activation to achieve the restoration of the worn monuments.Partiendo de 30 aislados bacterianos de diferentes tipos (fundamentalmente Bacillus), previamente aislados e identificados por métodos microbiológicos y moleculares, provenientes de biopelículas epilíticas traídas del Castillo de Chapultepec de la ciudad de México, DF. Se realizaron diferentes metodologías como comprobación y determinación de formación biopelículas y su cuantificación, prueba de ureasa y la producción de cristales de carbonato de calcio en placa Petry con LB enriquecido con carbonato de calcio al 0.2 %. Los cristales fueron enviados a difracción de rayos X y Microscopia Electrónica de Barrido.Los resultados muestran que en alguna medida todos los microorganismos probados  participan en el proceso de formación de biopelículas y un total de 12 aislados destacaron como los mejores formadores de biopelículas, sobresaliendo las cepas IS16 y IIIS10 (Bacillus subtilis), IIS15a (Bacillus cereus) por ser las que mayores UFC/mL presentaron en la biopelícula. Todos los buenos formadores de biopelículas resultan también adecuados en cuanto a bioprecipitación de carbonatos, destacando las cepas IIIS4 (Bacillus megaterium), IS5 (Bacillus subtilis) e IIIS9b (Bacillus subtilis), 21 (Pantoea agglomerans) y la IIIS5 (Bacillus simplex). Poco o nada se sabe hasta el momento de la participación de Pantoea agglomerans en procesos de biorrestauración mediante bioprecipitación de cristales de carbonato de calcio y debido a que se obtuvo buena respuesta a la prueba de ureasa y los cristales obtenidos fueron mayormente Calcita (99 %), este trabajo muestra la factibilidad de usar la biota nativa para su activación y así lograr la restauración de los monumentos biodeteriorados

LA BIOPRECIPITACIÓN DE CARBONATO DE CALCIO POR LA BIOTA NATIVA COMO UN MÉTODO DE RESTAURACIÓN

Partiendo de 30 aislados bacterianos de diferentes tipos (fundamentalmente Bacillus), previamente aislados e identificados por métodos microbiológicos y moleculares, provenientes de biopelículas epilíticas aisladas del Castillo de Chapultepec de la ciudad de México, DF. Se realizaron diferentes metodologías como comprobación de capacidad para formar biopelículas y su cuantificación, prueba de ureasa y la producción de cristales de carbonato de calcio en placa Petry con Luria Bertani enriquecido con carbonato de calcio al 0.2 %. Los cristales fueron enviados a difracción de rayos X y Microscopia Electrónica de Barrido. Los resultados muestran que en alguna medida todos los microorganismos probados participan en el proceso de formación de biopelículas y un total de 12 aislados destacaron como los mejores formadores de biopelículas, sobresaliendo las cepas IS16 y IIIS10 (Bacillus subtilis), IIS15a (Bacillus cereus) por ser las que mayores UFC/mL presentaron en la biopelícula. Todos los buenos formadores de biopelículas resultan también adecuados en cuanto a bioprecipitación de carbonatos, destacando las cepas IIIS4 (Bacillus megaterium), IS5 (Bacillus subtilis), IIIS9b (Bacillus subtilis), 21 (Pantoea agglomerans) y la IIIS5 (Bacillus simplex). Poco o nada se sabe hasta el momento de la participación de Pantoea agglomerans en procesos de biorrestauración mediante bioprecipitación de cristales de carbonato de calcio y debido a que se obtuvo buena respuesta a la prueba de ureasa y los cristales obtenidos fueron mayormente Calcita (99 %), este trabajo muestra la factibilidad de usar la biota nativa para su activación y así lograr la restauración de los monumentos biodeteriorados

Microorganisms as a Potential Source of Molecules to Control Trypanosomatid Diseases

Trypanosomatids are the causative agents of leishmaniasis and trypanosomiasis, which affect about 20 million people in the world’s poorest countries, leading to 95,000 deaths per year. They are often associated with malnutrition, weak immune systems, low quality housing, and population migration. They are generally recognized as neglected tropical diseases. New drugs against these parasitic protozoa are urgently needed to counteract drug resistance, toxicity, and the high cost of commercially available drugs. Microbial bioprospecting for new molecules may play a crucial role in developing a new generation of antiparasitic drugs. This article reviews the current state of the available literature on chemically defined metabolites of microbial origin that have demonstrated antitrypanosomatid activity. In this review, bacterial and fungal metabolites are presented; they originate from a range of microorganisms, including cyanobacteria, heterotrophic bacteria, and filamentous fungi. We hope to provide a useful overview for future research to identify hits that may become the lead compounds needed to accelerate the discovery of new drugs against trypanosomatids

Characterization of sulfate-reducing bacteria dominated surface communities during start-up of a down-flow fluidized bed reactor

An anaerobic down-flow fluidized bed reactor was inoculated with granular sludge and started-up with sulfate containing synthetic wastewater to promote the formation of a biofilm enriched in sulfate-reducing bacteria (SRB), to produce biogenic sulfide. The start-up was done in two stages operating the reactor in batch for 45 days followed by 85 days of continuous operation. Low-density polyethylene was used as support. The biofilm formation was followed up by biochemical and electron microscopy analyses and the composition of the community was examined by 16S rDNA sequence analysis. Maximum immobilized volatile solids (1.2 g IVS/L) were obtained after 14 days in batch regime. During the 85 days of continuous operation, the reactor removed up to 80% of chemical oxygen demand (COD), up to 28% of the supplied sulfate and acetate was present in the effluent. Sulfate-reducing activity determined in the biofilm with ethanol or lactate as substrate was 11.7 and 15.3 g COD/g IVS per day, respectively. These results suggested the immobilization of sulfate reducers that incompletely oxidize the substrate to acetate; the phylogenetic analysis of the cloned 16S rDNA gene sequences showed high identity to the genus Desulfovibrio that oxidizes the substrates incompletely. In contrast, in the granular sludge used as inoculum a considerable number of clones showed homology to Methanobacterium and just few clones were close to SRB. The starting-up approach allowed the enrichment of SRB within the diverse community developed over the polyethylene support