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Humans have long relied on microbial communities to create products, produce energy, and treat waste. The microbiota residing within our bodies directly impacts our health, while the soil and rhizosphere microbiomes influence the productivity of our crops. However, the complexity and diversity of microbial communities make them challenging to study and difficult to develop into applications, as they often exhibit the emergence of unpredictable higher-order phenomena. Synthetic ecology aims at simplifying complexity by constituting synthetic or semi-natural microbial communities with reduced diversity that become easier to study and analyze. This strategy combines methodologies that simplify existing complex systems (top-down approach) or build the system from its constituent components (bottom-up approach). Simplified communities are studied to understand how interactions among populations shape the behavior of the community and to model and predict their response to external stimuli. By harnessing the potential of synthetic microbial communities through a multidisciplinary approach, we can advance knowledge of ecological concepts and address critical public health, agricultural, and environmental issues more effectively.

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Objective: Pain, stress, and diabetes mellitus (DM) are common complaints for Guatemalans seeking health care. Because acupuncture therapy (AT) is a low-cost, effective treatment for these concerns, it was offered to Guatemalans during a health care mission as an adjunct to primary care. The purpose of this study was to gather feedback about providing AT in this context and to describe the lessons that were learned. Materials and Methods: A pretest single-arm exploratory study design was used, collecting demographic data and administering a pretest to patients referred for AT. Patients received AT according to presenting symptoms, except patients with DM, who were treated with a previously developed auricular AT protocol. After AT, all patients received adhesive seeds for self-administered auricular acupressure, along with a printed diagram, showing where and how to apply them, and a symptom-tracking form. Results: AT was given to 11 patients (1 had DM; 10 did not). Most were female (9; 82%), older (average 59.27 years; range: 40-81 years), and had little education (average 4 years; range: 0-12 years). Complaints were pain (11; 100%), insomnia (6; 55%), anxiety (4; 36%), depression (7; 64%), and stress (3; 27%). More than 50% had seen health care providers (6; 55%). One person had AT previously and 3 people requested more information about AT before receiving it. Conclusions: Reporting high symptom burdens, most patients were unfamiliar with AT. AT ceased when the licensed acupuncturist contracted COVID. Patients will be followed in 2023 and AT will be given to collect data on feasibility, satisfaction, and possible implementation.

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Over 200 different SARS-CoV-2 lineages have been observed in Mexico by November 2021. To investigate lineage replacement dynamics, we applied a phylodynamic approach and explored the evolutionary trajectories of five dominant lineages that circulated during the first year of local transmission. For most lineages, peaks in sampling frequencies coincided with different epidemiological waves of infection in Mexico. Lineages B.1.1.222 and B.1.1.519 exhibited similar dynamics, constituting clades that likely originated in Mexico and persisted for >12 months. Lineages B.1.1.7, P.1 and B.1.617.2 also displayed similar dynamics, characterized by multiple introduction events leading to a few successful extended local transmission chains that persisted for several months. For the largest B.1.617.2 clades, we further explored viral lineage movements across Mexico. Many clades were located within the south region of the country, suggesting that this area played a key role in the spread of SARS-CoV-2 in Mexico.

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Microbial communities can be considered complex adaptive systems. Understanding how these systems arise from different components and how the dynamics of microbial interactions allow for species coexistence are fundamental questions in ecology. To address these questions, we built a three-species synthetic community, called BARS (Bacillota A + S + R). Each species in this community exhibits one of three ecological roles: Antagonistic, Sensitive, or Resistant, assigned in the context of a sediment community. We show that the BARS community reproduces features of complex communities and exhibits higher-order interaction (HOI) dynamics. In paired interactions, the majority of the S species (Sutcliffiella horikoshii 20a) population dies within 5 min when paired with the A species (Bacillus pumilus 145). However, an emergent property appears upon adding the third interactor, as antagonism of species A over S is not observed in the presence of the R species (Bacillus cereus 111). For the paired interaction, within the first 5 min, the surviving population of the S species acquires tolerance to species A, and species A ceases antagonism. This qualitative change reflects endogenous dynamics leading to the expression for tolerance to an antagonistic substance. The stability reached in the triple interaction exhibits a nonlinear response, highly sensitive to the density of the R species. In summary, our HOI model allows the study of the assembly dynamics of a three-species community and evaluating the immediate outcome within a 30 min frame. The BARS has features of a complex system where the paired interactions do not predict the community dynamics. The model is amenable to mechanistic dissection and to modeling how the parts integrate to achieve collective properties.

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Microbial mats are biologically diverse communities that are analogs to some of the earliest ecosystems on Earth. In this study, we describe a unique transiently hypersaline microbial mat uncovered in a shallow pond within the Cuatro Cienegas Basin (CCB) in northern México. The CCB is an endemism-rich site that harbors living stromatolites that have been studied to understand the conditions of the Precambrian Earth. These microbial mats form elastic domes filled with biogenic gas, and the mats have a relatively large and stable subpopulation of archaea. For this reason, this site has been termed archaean domes (AD). The AD microbial community was analyzed by metagenomics over three seasons. The mat exhibited a highly diverse prokaryotic community dominated by bacteria. Bacterial sequences are represented in 37 phyla, mainly Proteobacteria, Firmicutes, and Actinobacteria, that together comprised >50% of the sequences from the mat. Archaea represented up to 5% of the retrieved sequences, with up to 230 different archaeal species that belong to 5 phyla (Euryarchaeota, Crenarchaeota, Thaumarchaeota, Korarchaeota, and Nanoarchaeota). The archaeal taxa showed low variation despite fluctuations in water and nutrient availability. In addition, predicted functions highlight stress responses to extreme conditions present in the AD, including salinity, pH, and water/drought fluctuation. The observed complexity of the AD mat thriving in high pH and fluctuating water and salt conditions within the CCB provides an extant model of great value for evolutionary studies, as well as a suitable analog to the early Earth and Mars.

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Human mobility networks are widely used for diverse studies in geography, sociology, and economics. In these networks, nodes usually represent places or regions and links refer to movement between them. They become essential when studying the spread of a virus, the planning of transit, or society's local and global structures. Therefore, the construction and analysis of human mobility networks are crucial for a vast number of real-life applications. This work presents a collection of networks that describe the human travel patterns between municipalities in Mexico in the 2020-2021 period. Using anonymized mobile location data, we constructed directed, weighted networks representing the volume of travels between municipalities. We analysed changes in global, local, and mesoscale network features. We observe that changes in these features are associated with factors such as COVID-19 restrictions and population size. In general, the implementation of restrictions at the start of the COVID-19 pandemic in early 2020, induced more intense changes in network features than later events, which had a less notable impact in network features. These networks will result very useful for researchers and decision-makers in the areas of transportation, infrastructure planning, epidemic control and network science at large.

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The seventh session of the Oncological Pathology Conference (JoPaO) entitled 'Pathological Anatomy in the context of the National Cancer Law: An overview of the Latin American experience', was held virtually on July 15, 22 and 23. Peru was the headquarters for this event, where 17 national and international professors of high academic standing participated. They interacted in a multidisciplinary context through talks with national panellists and the general public. The recent promulgation of the 'National Cancer Law' fosters the development of discussion forums to analyse the national realities and uphold continuous learning about experiences in other Latin American countries with successful cancer programmes, in which pathology holds a principal role. The topics addressed during this JoPaO included the exchange of Latin American cancer management experiences, an emphasis on investments in and the development of strategic plans to improve care, the use of new technologies, laboratory quality control, and the need to advance scientific research.

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[ABSTRACT]. Objective. This paper assesses the availability and quality of death certificate data in Latin America and the feasibility of using these data to study place of death and associated factors. Methods. In this comparative study, we collected examples of current official death certificates and digital data files containing information about all deaths that occurred during 1 year in 19 Latin American countries. Data were collected from June 2019 to May 2020. The records for place of death and associated variables were studied. The criteria for data quality were completeness, number of ill-defined causes of death and timeliness. Results. All 19 countries provided copies of current official death certificates and 18 of these registered the place of death. Distinguishing among hospital or other health care institution, home and other was possible for all countries. Digital data files with death certificate data were available from 12 countries and 1 region. Three countries had data considered to be of high quality and seven had data considered to be of medium quality. Categories for place of death and most of the predetermined factors possibly associated with place of death were included in the data files. Conclusions. The quality of data sets was rated medium to high in 10 countries. Hence, death certificate data make it feasible to conduct an international comparative study on place of death and the associated factors in Latin America.

[RESUMEN]. Objetivo. En este artículo se evalúa la disponibilidad y la calidad de los datos del certificado de defunción en América Latina y la factibilidad de emplear estos datos para estudiar el lugar de defunción y factores asociados. Métodos. En este estudio comparativo, se recogieron ejemplos de certificados oficiales de defunción actuales y archivos digitales de datos que contenían información acerca de todas las defunciones que ocurrieron durante un año en 19 países latinoamericanos. Se recopilaron datos desde junio del 2019 hasta mayo del 2020. Se estudiaron los registros del lugar de la muerte y las variables asociadas. Los criterios para determinar la calidad de los datos fueron la exhaustividad, el número de causas de muerte mal definidas y la presentación oportuna de la información. Resultados. Los 19 países proporcionaron copias de los certificados oficiales de defunción actuales; en 18 de estos se registraba el lugar de la muerte. En todos los países fue posible distinguir entre hospital u otra institución de atención de salud, el hogar y otros. Se obtuvieron los archivos de datos digitales con los datos del certificado de defunción de 12 países y una región. Tres países tenían datos considerados de buena calidad y siete tenían datos considerados de calidad media. En los archivos de datos se incluyeron categorías para lugar de defunción y la mayoría de los factores predeterminados posiblemente asociados con el lugar de defunción. Conclusiones. La calidad de los conjuntos de datos se calificó de media a buena en 10 países. En consecuencia, es factible realizar un estudio internacional comparativo sobre el lugar de defunción y los factores asociados en América Latina con los datos del certificado de defunción.

[RESUMO]. Objetivo. Este estudo avalia a disponibilidade e a qualidade dos dados das declarações de óbito na América Latina e a viabilidade de usar esses dados para estudar o local do óbito e fatores associados. Métodos. Neste estudo comparativo, coletamos exemplos de declarações de óbito oficiais atuais e arquivos de dados digitais contendo informações sobre todos os óbitos que ocorreram durante 1 ano em 19 países latinoamericanos. Os dados foram coletados no período de junho de 2019 a maio de 2020. Foram estudados os registros do local do óbito e variáveis associadas. Os critérios de qualidade dos dados foram preenchimento completo, número de causas mal definidas de morte e oportunidade. Resultados. Todos os 19 países forneceram cópias das declarações de óbito oficiais atuais, e 18 deles registraram o local do óbito . Foi possível distinguir em todos os países entre hospital ou outra instituição de saúde, lar ou outro local. Arquivos de dados digitais com os dados das declarações de óbito foram disponibilizados por 12 países e 1 região. Três países tiveram dados considerados de alta qualidade, e sete tiveram dados considerados de qualidade média. As categorias de local do óbito e a maioria dos fatores predeterminados possivelmente associados ao local do óbito foram incluídos nos arquivos de dados. Conclusões. A qualidade dos conjuntos de dados foi classificada como média a alta em 10 países. Portanto, os dados de declarações de óbito possibilitam a realização de um estudo comparativo internacional sobre local do óbito e fatores associados na América Latina.

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BACKGROUND: Neuromyelitis optica spectrum disorders (NMOSDs) are a group of chronic immune-mediated demyelinating diseases of the central nervous system. Their pathophysiology dependent on humoral mediated responses caused by autoreactive IgG antibodies against aquaporin-4 water channels (AQP4-IgG) or myelin oligodendrocyte glycoprotein (MOG-IgG). Plasma exchange (PLEX) has proved to be a beneficial therapy in patients with severe relapses. We present the largest series of Latin American patients treated with PLEX for acute NMOSDs relapses. METHODS: A retrospective study was conducted. Selection included patients diagnosed with NMOSDs who received PLEX between 2010-2019, irrespective of their AQP4-IgG serostatus. All patients received 5 grams of IV methylprednisolone. PLEX therapy could be initiated simultaneously or after IV steroids. Baseline and post-PLEX therapy Expanded Disability Status Scale (EDSS) was measured to identify acute response to therapy. Comparison between responders and non-responders was also conducted. Subgroup analysis stratified response by serostatus, type of clinical relapse and time to PLEX. RESULTS: A total of 89 patients were included. Mean age at onset was 38 ± 12.97 years. 49 (55.1%) patients were AQP4-IgG seropositive. Most patients had unilateral optic neuritis (34.8%) or longitudinally extensive transverse myelitis (33.7%). Mean time from onset to PLEX initiation was 20.9 ± 18.1 days. Response rate was 39.3% and mean decline in EDSS was 0.7 ± 0.9 (p <0.001). Decline in EDSS and response rate were independent of serostatus, type of clinical relapse or time to PLEX initiation. CONCLUSION: PLEX appears to be an effective therapy for NMOSDs relapses even in limited resources setting where treatment initiation may be delayed. The benefit seems to be independent of the type of clinical relapse and AQP4 IgG serostatus.

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Resumen: Introducción: los cuidados paliativos (CP) son un marcador de calidad de asistencia en terapia intensiva; sin embargo, han sido poco evaluados en Uruguay. La detección proactiva de pacientes mediante disparadores de consultas es una estrategia que podría optimizar el acceso a los CP. Objetivos: determinar la prevalencia y las características de los disparadores de consulta de CP en pacientes críticos. Analizar la utilización de recursos en estos pacientes. Material y método: estudio de cohorte, retrospectivo, que incluyó pacientes ingresados a unidad de cuidados intensivos (UCI) entre marzo de 2016 y febrero de 2019. Los disparadores analizados fueron: a) presencia de tumor con metástasis; b) estadía en UCI 50% por encima de la media (14 días); c) >75 años con disfunción orgánica múltiple, y d) >80 años con dos o más comorbilidades graves. Resultados: se analizaron 2.850 pacientes. El 26% (734) presentó al menos un disparador de consulta con CP. El más prevalente: estadía en UCI 50% por encima de la media (18%). Estos pacientes presentaron mayor edad: 61 (43-75) vs 54 (36-65) años (p < 0,001) y mayor gravedad, SAPSIII de 60 (48-74) vs 47 (35-61) puntos (p<0,001). Requirieron más asistencia respiratoria mecánica (ARM) 87% vs 55% (p <0,001), vasopresores 48% vs 24% (p< 0,001) y hemodiálisis 8% vs 4% (p<0,001). Presentaron mayor estadía 18 (9-27) vs 4 (2-8) días, (p<0,001) y tiempo en ARM 14 (7-23) vs 3 (1- 6) días (p<0,001). Conclusiones: la cuarta parte de los pacientes en UCI activaron al menos un criterio de CP, presentaron mayor gravedad y utilizaron más sostén de soporte vital.

Summary: Introduction: palliative care (PC) constitutes a marker of the quality of intensive care assistance. However, it has not been thoroughly assessed in Uruguay. Proactive detection of patients by means of "consultation triggers" should be considered a strategy to optimize access to PC. Objetives: to determine the prevalence and characteristics of Palliative Care consultation triggers in critical patients. To analyse the use of resources in these patients. Method: retrospective cohort study of patients admitted in the ICU between March 2016 and February 2019. The following triggers were identified: a) a tumor with metastasis; length of stay at the ICU 50% over the average (14 days), c) >75 years old with multiple organic dysfunction and d) >80 years old with 2 or more severe comorbidities Results: 2.850 patients were analysed. 26% (734) presented at least one consultation trigger with PC. Length of stay at the ICU 50% over average (18%). These patients presented higher average age 61 (43-75) versus 54 (36-65) years old (p < 0.001), and increased severity, SAPSIII of 60 (48-74) compared to 47 (35-61) points (p<0.001); 87% required mechanical ventilation compared to 55% (p <0.001), vasopressors 48% compared to 24% (p< 0.001) and hemodialysis 8% compared to 4% (p<0.001). 18 presented a longer stay (9-27) compared to 4 (2-8) days, (p<0.001) and time on mechanical ventilation 14 (7-23) compared to 3 (1- 6) days (p<0.001). Conclusions: 25 percent of patients in the ICU activated at least one criterion for PC, they were in a more severe condition and used more mechanical ventilation.

Resumo: Introdução: os cuidados paliativos (CP) são um marcador de qualidade da atenção em Terapia Intensiva, porém, pouco avaliados no Uruguai. A detecção proativa de pacientes usando "gatilhos de consulta" é uma estratégia que pode otimizar o acesso aos CP. Metas: determinar a prevalência e as características dos critérios de elegibilidade de CP em pacientes críticos. Analisar o uso de recursos nesses pacientes. Materiais e métodos: estudo de coorte retrospectivo, incluindo pacientes internados na UTI entre março de 2016 e fevereiro de 2019. Os critérios analisados foram: a) presença de tumor com metástase, b) permanência na UTI 50% acima da média (14 dias), c ) >75 anos com disfunção de múltiplos órgãos e d) >80 anos com 2 ou mais comorbidades graves. Resultados: 2.850 pacientes foram analisados. 26% (734) apresentaram pelo menos 1 critério de elegibilidade para CP. O mais prevalente foi a permanecia na UTI 50% superior à média (18%). Esses pacientes tinham mais de 61 anos (43-75) vs 54 (36-65) anos (p <0,001) e condições mais graves, SAPSIII de 60 (48-74) vs 47 (35-61) pontos (p <0,001). Necessitaram mais ventilação mecânica assistida (AVM) 87% vs 55% (p <0,001), vasopressores 48% vs 24% (p <0,001) e hemodiálise 8% vs 4% (p <0,001). Tiveram uma permanência mais prolongada 18 (9-27) vs 4 (2-8) dias, (p <0,001) e tempo em AVM 14 (7-23) vs 3 (1-6) dias (p <0,001). Conclusões: um quarto dos pacientes internados na UTI ativou pelo menos um critério de elegibilidade para CP, apresentou maior gravidade e utilizou mais suporte vital.

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La sexualidad es una de las áreas que sufre cambios importantes cuando la mujer se instala en el climaterio, estos cambios se conocen como trastornos y/o disfunciones sexuales. Material y método: en el Instituto Nacional de Perinatología se llevó a cabo un estudio con 139 mujeres en climaterio; se utilizó la encuesta de síntomas y la Historia Clínica Codificada de la Sexualidad Femenina (HCCSF) para conocer la presencia de las disfunciones y/o trastornos sexuales y los factores asociados a estos. Resultados: no se encontró relación alguna entre las variables sociodemográficas y la presencia de disfunciones sexuales; de la muestra, 124 mujeres presentaron al menos una disfunción sexual. Conclusión: aquellas mujeres que cuentan con información sexual a edades tempranas, que tienen deseo y cooperan durante la relación sexual y que además han explorado su sexualidad con más de una pareja, tienen un efecto protector para no presentar disfunciones sexuales. Por otra parte, la presencia de trastornos sexuales se asocia exclusivamente con padecimientos médicos y de salud en la mujer como en la pareja.

Sexuality is one of the areas that undergoes important changes when women settle in climacteric, these changes are known as sexual disorders and/or dysfunctions. Methods: A study was carried out at the National Institute of Perinatology with 139 women in climacteric. The survey of symptoms and the Codified Clinical History of Female Sexuality (HCCSF) were used to determine the presence of sexual dysfunctions and/or disorders and the factors associated with them. Results: No relationship was found between sociodemographic variables and the presence of sexual dysfunctions. Of the sample, 124 women presented at least one sexual dysfunction. Conclusion: Those women who have sexual information at an early age, who have desire and cooperate during sexual intercourse and who have explored their sexuality with more than one partner, have a protective effect for not presenting sexual dysfunctions. On the other hand, the presence of sexual disorders is associated exclusively with medical and health conditions in both the woman and the couple.

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Objective: this paper assesses the availability and quality of death certificate data in Latin America and the feasibility of using these data to study place of death and associated factors. Methods: in this comparative study, we collected examples of current official death certificates and digital data files containing information about all deaths that occurred during 1 year in 19 Latin American countries. Data were collected from June 2019 to May 2020. The records for place of death and associated variables were studied. The criteria for data quality were completeness, number of ill-defined causes of death and timeliness. Results: all 19 countries provided copies of current official death certificates and 18 of these registered the place of death. Distinguishing among hospital or other health care institution, home and other was possible for all countries. Digital data files with death certificate data were available from 12 countries and 1 region. Three countries had data considered to be of high quality and seven had data considered to be of medium quality. Categories for place of death and most of the predetermined factors possibly associated with place of death were included in the data files. Conclusions: the quality of data sets was rated medium to high in 10 countries. Hence, death certificate data make it feasible to conduct an international comparative study on place of death and the associated factors in Latin America.

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The association between frontal fibrosing alopecia and lichen planus pigmetosus was first described in African women. Later, most reports about this association involved dark-skinned patients. Here, we describe 5 cases of frontal fibrosing alopecia associated with lichen planus pigmentosus in light-skinned women from Argentina. Our communication highlights the strength of both entities' association also in lower Fitzpatrick phototypes.

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[This corrects the article DOI: 10.1128/genomeA.00364-18.].

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The presence of duplicated genes in organisms is well documented. There is increasing interest in understanding how these genes subfunctionalize and whether functional overlap can explain the fact that some of these genes are dispensable. Bacillus subtilis possesses four DEAD-box RNA helicases (DBRH) genes, cshA, cshB, deaD/yxiN, and yfmL that make a good case to study to what extent they can complement each other despite their subfunctionalization. They possess the highly conserved N-terminal catalytic domain core common to RNA helicases, but different carboxy-terminal ends. All four genes have been shown to have independent functions although all participate in rRNA assembly. None of the B. subtilis DBRH is essential for growth at 37°C, and all single deletion mutants exhibit defective growth at 18°C except for ΔdeaD/yxiN. Evaluation of double mutants did not reveal negative epistasis, suggesting that they do not have overlapping functions. The absence of any one gene distorts the expression pattern of the others, but not in a specific pattern suggestive of compensation. Overexpression of these paralogous genes in the different mutant backgrounds did not result in cross-complementation, further confirming their lack of buffering capability. Since no complementation could be observed among full sized proteins, we evaluated to what extent the superfamily 2 (SF2) helicase core of the smallest DBRH, YfmL, could be functional when hooked to each of the C-terminal end of CshA, CshB, and DeaD/YxiN. None of the different chimeras complemented the different mutants, and instead, all chimeras inhibited the growth of the ΔyfmL mutant, and other combinations were also deleterious. Our findings suggest that the long time divergence between DEAD-box RNA helicase genes has resulted in specialized activities in RNA metabolism and shows that these duplicated genes cannot buffer one another.

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PURPOSE OF REVIEW: To describe how Project ECHO works and to analyze what has been published on Project ECHO Palliative Care (Project ECHO PC) over the last 18 months. RECENT FINDINGS: Only two articles on Project ECHO PC have been published over the last 18 months: a descriptive study of experiences in seven health centers of the United States, the United Kingdom, Uruguay and India; and a quantitative and qualitative study of the impact of the teleECHO clinic on physicians and nurses in Northern Ireland, which reports a significant boost in knowledge acquisition and self-efficacy. SUMMARY: Project ECHO is an innovative telemedicine strategy, which creates learning communities, which use a standardized methodology and benefits healthcare professionals, particularly primary care providers or practitioners based on remote or rural areas.Since 2011, Project ECHO PC has been implemented in 12 health centers in 4 different countries, with greater growth in 2017. It has facilitated a wider access to professional education, improvements in clinical practice and knowledge acquisition, the development of professional curricula and more confidence and self-efficacy among healthcare professionals. Project ECHO PC is engaged in several international initiatives to aid countries with different degrees of palliative care development.

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BACKGROUND: Members of the Bacillus genus have been isolated from a variety of environments. However, the relationship between potential metabolism and the niche from which bacteria of this genus have been isolated has not been extensively studied. The existence of a monophyletic aquatic Bacillus group, composed of members isolated from both marine and fresh water has been proposed. Here, we present a phylogenetic/phylogenomic analysis to investigate the potential relationship between the environment from which group members have been isolated and their evolutionary origin. We also carried out hierarchical clustering based on functional content to test for potential environmental effects on the genetic content of these bacteria. RESULTS: The phylogenetic reconstruction showed that Bacillus strains classified as aquatic have evolutionary origins in different lineages. Although we observed the presence of a clade consisting exclusively of aquatic Bacillus, it is not comprised of the same strains previously reported. In contrast to phylogeny, clustering based on the functional categories of the encoded proteomes resulted in groups more compatible with the environments from which the organisms were isolated. This evidence suggests a detectable environmental influence on bacterial genetic content, despite their different evolutionary origins. CONCLUSION: Our results suggest that aquatic Bacillus species have polyphyletic origins, but exhibit convergence at the gene content level.

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We assembled the complete genome sequences of Bacillus pumilus strains 145 and 150a from Cuatrociénegas, Mexico. We detected genes codifying for proteins potentially involved in antagonism (bacteriocins) and defense mechanisms (abortive infection bacteriophage proteins and 4-azaleucine resistance). Both strains harbored prophage sequences. Our results provide insights into understanding the establishment of microbial interactions.

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Phosphite, a species of phosphorus in a P3+ oxidation state, is believed to have played an important role in the primordial Earth. Figueroa et al. used metagenomics to uncover anaerobic bacterial communities from waste water waste sludge that sustain life from energy provided by phosphite.

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ABSTRACT Coffee rust is a fungal disease that has affected every coffee-producing region in the world. Given that the effectivity of the protectant and systemic fungicides applied routinely to control the spread of the causative agent of the disease (Hemileia vastatrix) has gradually diminished, besides are harmful to mammals and ecosystems, the objective of this work was to search for a mixture of harmless natural compounds with the potential to be applied in the field. So, a yeast strain producing a battery of long-chain carboxylic acids (CA) with fungicide properties was isolated from soil of coffee crop and identified as Pichia membranifaciens by ITS sequencing. Culture conditions of the yeast were optimized and the CA in the solution were characterized by Gas Chromatography-Mass Spectrometry (GC-MS) as ethyl formate (55.5 g L-1), octadecenoic acid (3.5 g L-1), propionic acid (7.2 g L-1), 3-(octadecanoyl)-propionic acid (7.2 g L-1) and methyl acetate (8.4 g L-1). Randomized field studies were conducted in three different locations in Chiapas, México. Five treatments were tested including three concentrations of the CA solution (389, 584 and 778 ppm) and copper oxychloride (5 000 ppm) as conventional control. The initial coffee rust incidence averages varied between sites: Maravillas (3-9%), Santo Domingo (10-16%) and Búcaro (16-22%). The treatments of CA solution proved to be effective at slowing down the progress of the rust disease even for the sites where initial incidence was high. Likewise, the CA solution reduced the viability of H. vastatrix spores, as assessed by fluorescence microscopy.

RESUMO A ferrugem do cafeeiro é uma doença que tem afetado as regiões produtoras de café no mundo. Considerando que os funguicidas protetores e sistemáticos que são aplicados rotinariamente para controlar a difusão do agente causador da doença (Hemileia vastatrix) são nocivos para os humanos, animais e ecossistemas, o objetivo deste trabalho é determinar um componente natural com potencial de uso. Uma cepa de levedura produzindo uma bateria de ácidos carboxílicos com ação funguicida foi isolada do solo e identificada como Pichia membranifaciens por sequenciamento ITS. Foram optimizadas as condições de cultura e os ácidos carboxílicos presentes na semi purificada sobrenadante (solução CA) foram caracterizados por cromatografia de gás espectometia de massa (GC-MS) como formato de etilo (55.5 g L-1), ácido octadecenóico (3.5 g L-1), ácido propiônico (7.2 g L-1), 3-(octadecanoil)-ácido propiônico 7.2 g L-1) e acetato de metilio (8.4 g L-1). Estudos do campo foram conduzidos em três locais na região de Chiapas, Mexico. Cinco tratamentos foram testados incluindo três concentrações da solução CA (389, 584 e 778 ppm) e o funguicida comercial contendo oxicloreto de cobre (500 ppm). As médias iniciais de incidência da ferrugem do cafeeiro variou em função do local: Maravilla (3-9%), Santo domingo (10-16%) e Búcaro (16-22%). A solução CA provou ser efetiva retardando o progresso da doença, mesmo nos locais onde a incidência inicial foi elevada. A solução CA reduziu a viabilidade dos esporos de H. Vastatrix, observado por meio de fluorescência.