Assessment of zinc solubilization potential of zinc-resistant Pseudomonas oleovorans strain ZSB13 isolated from contaminated soil / Avaliação do potencial de solubilização do zinco da cepa ZSB13 de Pseudomonas oleovorans resistente ao zinco isolada de solo contaminado

Zinc is an essential micronutrient that is required for optimum plant growth. It is present in soil in insoluble forms. Bacterial solubilization of soil unavailable form of Zn into available form, is an emerging approach to alleviate the Zn deficiency for plants and human beings. Zinc solubilizing bacteria (ZSB) could be a substitute for chemical Zn fertilizer. The present study aimed to isolate and characterize bacterial species from the contaminated soil and evaluate their Zn solubilizing potential. Zn resistant bacteria were isolated and evaluated for their MIC against Zn. Among the 13 isolated bacterial strains ZSB13 showed maximum MIC value upto 30mM/L. The bacterial strain with the highest resistance against Zn was selected for further analysis. Molecular characterization of ZSB13 was performed by 16S rRNA gene amplification which confirmed it as Pseudomonas oleovorans. Zn solubilization was determined through plate assay and broth medium. Four insoluble salts (zinc oxide (ZnO), zinc carbonate (ZnCO3), zinc sulphite (ZnS) and zinc phosphate (Zn3(PO4)2) were used for solubilization assay. Our results shows 11 mm clear halo zone on agar plates amended with ZnO. Likewise, ZSB13 showed significant release of Zn in broth amended with ZnCO3 (17 and 16.8 ppm) and ZnO (18.2 ppm). Furthermore, Zn resistance genes czcD was also enriched in ZSB13. In our study, bacterial strain comprising Zn solubilization potential has been isolated that could be further used for the growth enhancement of crops.

O zinco é um micronutriente essencial necessário para o crescimento ideal das plantas. Ele está presente no solo em formas insolúveis. A solubilização bacteriana da forma indisponível de Zn no solo para a forma disponível é uma abordagem emergente para aliviar a deficiência de Zn em plantas e seres humanos. Bactérias solubilizadoras de zinco (ZSB) podem ser um substituto para fertilizantes químicos de Zn. O presente estudo teve como objetivo isolar e caracterizar espécies bacterianas de solo contaminado e avaliar seu potencial de solubilização de Zn. Bactérias resistentes ao Zn foram isoladas e avaliadas quanto ao seu MIC contra o Zn. Entre as 13 cepas bacterianas isoladas, ZSB13 apresentou valor máximo de MIC de até 30 mM/L. A cepa bacteriana com maior resistência ao Zn foi selecionada para análise posterior. A caracterização molecular de ZSB13 foi realizada por amplificação do gene 16S rRNA que o confirmou como Pseudomonas oleovorans. A solubilização do Zn foi determinada através de ensaio em placa e meio caldo. Quatro sais insolúveis (óxido de zinco (ZnO), carbonato de zinco (ZnCO3), sulfito de zinco (ZnS) e fosfato de zinco (Zn3 (PO4) 2) foram usados para o ensaio de solubilização. Nossos resultados mostram uma zona de halo clara de 11 mm em placas de ágar corrigidas com ZnO. Da mesma forma, ZSB13 mostrou liberação significativa de Zn em caldo alterado com ZnCO3 (17 e 16,8 ppm) e ZnO (18,2 ppm). Além disso, os genes de resistência ao Zn czcD também foram enriquecidos em ZSB13. Em nosso estudo, a cepa bacteriana compreendendo potencial de solubilização de Zn foi isolada e poderia ser usada posteriormente para o aumento do crescimento de safras.

Complicaciones por accesos venosos centrales en pacientes adultos / Complications due to central venous access in adult patients

Los accesos venosos centrales son técnicas de uso regular en el ámbito hospitalario, es por ello que la investigación tiene como Objetivo: Establecer la incidencia de complicaciones asociadas a la colocación de accesos venosos centrales en pacientes atendidos en el Hospital Militar Universitario "Dr. Carlos Arvelo". Métodos: estudio prospectivo, de selección intencional de pacientes en el ámbito hospitalario que presenten complicaciones asociadas a la canalización de accesos venosos centrales; a los cuales se les aplicó un cuestionario donde se registraron, además de datos demográficos y clínicos, los resultados del funcionamiento del acceso venoso central. Al séptimo día se retiró o se recambió el acceso venoso central y se tomó muestra para cultivo y antibiograma de la punta de catéter. Los datos fueron tabulados, analizados en gráficos y tablas. Resultados: Uno de los principales hallazgos fueron las complicaciones infecciosas en un 65.93 % y producto de complicaciones mecánicas un 34.05 % del grupo de estudio. Las complicaciones infecciosas fueron atribuibles en su mayoría a Staphylococcus aureus (27,39 %), Pseudomona sp (21,91 %), Stenotrophomonas maltophilia (16,44%), Burkholderia cepacia (10,95 %) y Klebsiella pneumonia (5,48 %). En cuanto al porcentaje de éxito de las intervenciones se encontró que el promedio de intentos fue de 5 con una desviación estándar de ± 3 intentos y una duración promedio menor a 30 minutos en 90 de los casos representando el 76,27 % y duración mayor de 30 minutos en 28 casos representando 23,7 %. Conclusiones: Los accesos venosos yugulares internos fueron los procedimientos más frecuentes seguido de los accesos subclavios, sin predilección de lateralidad alguna. Al revisar los hallazgos se puede evidenciar que la punción arterial se convierte en la complicación mecánica más frecuente produciendo hematomas y equimosis con un alto porcentaje de intentos superiores a 30 minutos o un número de intentos mayores a tres, así como las complicaciones infecciosas generadas por el Staphylococcus aureus y sin que dichas complicaciones se encontraran asociadas al tipo de abordaje estudiado, tiempo de intervención u otros factores de carácter demográfico(AU)

Central venous accesses are a technique of regular use in the hospital environment, that is why the objective of this research is: to establish the incidence of complications treated at the University Military Hospital "Dr. Carlos Arvelo". Methods: prospective study, of intentional selection of patients in the hospital setting who present complications associated to the cannulation of central venous accesses; to whom a questionnaire was applied where, in addition to demographic and clinical data, the results of the central venous access operation were registered. On the seventh day, the central venous access was removed or replaced and a sample was taken for culture and antibiogram of the catheter tip. Data were tabulated, analyzed in graphs and tables. Results: One of the main findings was infectious complications in 65.93 % and mechanical complications in 34.05 % of the study group. Infectious complications were mostly attributable to Staphylococcus aureus (27.39 %), Pseudomona sp (21.91 %), Stenotrophomonas maltophilia (16.44 %), Burkholderia cepacia (10.95 %) and Klebsiella pneumonia (5.48 %). Regarding the percentage of success of the interventions, it was found that the average number of attempts was 5 with a standard deviation of ± 3 attempts and an average duration of less than 30 minutes in 90 of the cases representing 76.27 % and duration greater than 30 minutes in 28 cases representing 23.7 %. Conclusions: Internal jugular venous accesses were the most frequent procedures followed by subclavian accesses, with no predilection for laterality. When reviewing the findings, it can be evidenced that arterial puncture becomes the most frequent mechanical complication producing hematomas and ecchymosis with a high percentage of attempts longer than 30 minutes or a number of attempts longer than three, as well as infectious complications generated by Staphylococcus aureus and without these complications being associated to the type of approach studied, time of intervention or other demographic factors(AU)

Inappropriate empirical antimicrobial treatment in bloodstream infections patients in the era of multidrug resistance / Terapia Empírica Inapropriada no Tratamento de Infecções de Corrente Sanguínea na Era da Multirresistência Antimicrobiana / Tratamiento antimicrobiano empírico inadecuado en pacientes con infecciones del torrente sanguíneo

Background and objectives: Bloodstream infection (BSI) by multidrug-resistant Pseudomonas aeruginosa is a severe infection. This study aimed to evaluate and identify the predictors of mortality in patients who had bloodstream infection by carbapenem-resistant P. aeruginosa. Methods: This is a retrospective cohort study, approved by Committee of Ethics in Research with Human Participants, which included 87 consecutive patients hospitalized in a referral hospital in Brazil. Clinical and demographic information about each patient were obtained from hospital records. The Student's T-test was used to compare continuous variables and x2 or Fisher's exact tests to compare categorical variables. To determine independent risk factors for 30-day mortality, a multiple logistic regression model was used. A survival curve was constructed using the Kaplan­Meier method. Results: Among the patients, 87.3% use antibiotics previously, 60.9% received inadequate empirical treatment, and the 30-day mortality rate was 57.5%. Inappropriate antibiotic empirical therapy was independently associated with a 30-days death and mortality rate. Conclusion: These findings can show some insights about the relationship between higher mortality and inappropriate empirical therapy for patients with BSI by P. aeruginosa. There is a need for better diagnostic tests and infection control programs should focus on de-escalation the antibiotic inappropriate therapy, mainly in BSI caused by carbapenem-resistant P. aeruginosa.(AU)

Justificativa e objetivos: Infecção da corrente sanguínea (ICS) por Pseudomonas aeruginosa multirresistente é grave. Este estudo teve como objetivo avaliar e identificar os preditores de mortalidade em pacientes admitidos em uma Unidade de Terapia Intensiva que apresentaram infecção da corrente sanguínea por P. aeruginosa resistente aos carbapenêmicos. Métodos: Trata-se de um estudo de coorte retrospectivo, aprovado pelo Comitê de Ética em Pesquisa com Seres Humanos, que incluiu 87 pacientes consecutivos internados em um hospital de referência no Brasil. As informações clínicas e demográficas de cada paciente foram obtidas através de análise dos prontuários dos pacientes. O teste T de Student foi usado para comparar variáveis contínuas e o teste x2 ou exato de Fisher para comparar variáveis categóricas. Para determinar fatores de risco independentes para mortalidade em 30 dias, foi utilizado um modelo de regressão logística múltipla. Uma curva de sobrevida foi construída pelo método de Kaplan-Meier. Resultados: Do total de pacientes, 87,3% faziam uso prévio de antibióticos, 60,9% receberam tratamento empírico inadequado e a mortalidade em 30 dias foi de 57,5%. A terapia empírica inadequada foi fator de risco independente para mortalidade. Conclusão: Esses achados revelam alguns insights sobre a relação entre maior mortalidade e terapia empírica inadequada para pacientes com ICS por P. aeruginosa. Além disso, destacam a necessidade de melhores testes diagnósticos e os programas de controle de infecção devem se concentrar na redução da terapia inadequada com antibióticos, principalmente na ICS causada por P. aeruginosa resistente a carbapenêmicos.(AU)

Justificación y objetivos: La infección del torrente sanguíneo por Pseudomonas aeruginosa multirresistente es grave. Este estudio tuvo como objetivo evaluar e identificar predictores de mortalidad en pacientes ingresados en una Unidad de Cuidados Intensivos que presentaban infección del torrente sanguíneo por P. aeruginosa resistente a carbapenémicos. Métodos: Se trata de un estudio de cohorte retrospectivo, aprobado por el Comité de Ética en Investigación con Participantes Humanos, que incluyó 87 pacientes consecutivos ingresados en un hospital de referencia en Brasil. La información clínica y demográfica de cada paciente se obtuvo mediante el análisis de las historias clínicas de los pacientes. Se utilizó la prueba t de Student para comparar variables continuas y x2 o prueba exacta de Fisher para comparar variables categóricas. Para determinar los factores de riesgo independientes para la mortalidad a los 30 días, se utilizó un modelo de regresión logística múltiple. Se construyó una curva de supervivencia utilizando el método de Kaplan-Meier. Resultados: Del total de pacientes, el 87,3% utilizaba antibióticos previamente, el 60,9% recibió tratamiento empírico inadecuado y la tasa de mortalidad a los 30 días fue del 57,5%. La terapia empírica inadecuada fue un factor de riesgo independiente de mortalidad. Conclusión: Estos hallazgos revelan algunos conocimientos sobre la relación entre el aumento de la mortalidad y la terapia empírica inadecuada para los pacientes con infección del torrente sanguíneo por P. aeruginosa. Además, destacan la necesidad de mejores pruebas de diagnóstico y los programas de control de infecciones deben centrarse en reducir la terapia con antibióticos inapropiados, particularmente en infección del torrente sanguíneo causados por P. aeruginosa resistente a carbapenémicos.(AU)

Biodegradation of petroleum by bacteria isolated from fishes of Indian Ocean / Biodegradação do petróleo por bactérias isoladas de peixes do oceano Índico

In this study, oil degrading bacteria discovered from fish living near the oil ports at Karachi in Pakistan were characterized. The bacteria isolated from skin, gills, and gut in fish could consume crude oil as a source of carbon and energy. Total 36 isolates were tested using Nutrient Agar (NA) and MSA media with different crude oil concentrations (0.2%, 0.5%, 0.7%, 1%, 2%, and 5%) and 4 out of 36 isolates (two Gram positive and two Gram negative bacteria) were selected for further identification. 16S rRNA gene sequencing revealed that the isolates are related to Bacillus velezensis, Bacillus flexus, Pseudomonas brenneri and Pseudomonas azotoforman. Oil degrading potential of these bacteria was characterized by GC-MS analysis of degradation of oil components in crude oil as well as engine oil. We found that one (2, 6, 10, 14-Tetramethylpentadecane) out of 42 components in the crude oil was fully eliminated and the other oil components were reduced. In addition, 26 out of 42 oil components in the engine oil, were fully eliminated and the rest were amended. Taken together, these studies identify that B. velezensis, B. flexus, P. brenneri and P. azotoforman have high oil degrading potential, which may be useful for degradation of oil pollutants and other commercial applications.

Neste estudo, bactérias degradadoras de óleo descobertas em peixes que vivem perto dos portos de petróleo em Karachi, no Paquistão, foram caracterizadas. As bactérias isoladas da pele, guelras e intestinos dos peixes podem consumir petróleo bruto como fonte de carbono e energia. No total, 36 isolados foram testados usando Agar Nutriente (NA) e meio MSA com diferentes concentrações de óleo bruto (0,2%, 0,5%, 0,7%, 1%, 2% e 5%) e 4 de 36 isolados (dois Gram positivos e duas bactérias Gram negativas) foram selecionadas para posterior identificação. O sequenciamento do gene 16S rRNA revelou que os isolados estão relacionados a Bacillus velezensis, Bacillus flexus, Pseudomonas brenneri e Pseudomonas azotoforman. O potencial de degradação do óleo dessas bactérias foi caracterizado pela análise de GC-MS da degradação dos componentes do óleo no óleo cru, bem como no óleo do motor. Descobrimos que um (2, 6, 10, 14-tetrametilpentadecano) de 42 componentes do óleo cru foi totalmente eliminado e os outros componentes do óleo foram reduzidos. Além disso, 26 dos 42 componentes do óleo do motor foram totalmente eliminados e o restante corrigido. Juntos, esses estudos identificam que B. velezensis, B. flexus, P. brenneri e P. azotoforman têm alto potencial de degradação de óleo, o que pode ser útil para a degradação de poluentes de óleo e outras aplicações comerciais.

Biodegradation of petroleum by bacteria isolated from fishes of Indian Ocean / Biodegradação do petróleo por bactérias isoladas de peixes do oceano Índico

In this study, oil degrading bacteria discovered from fish living near the oil ports at Karachi in Pakistan were characterized. The bacteria isolated from skin, gills, and gut in fish could consume crude oil as a source of carbon and energy. Total 36 isolates were tested using Nutrient Agar (NA) and MSA media with different crude oil concentrations (0.2%, 0.5%, 0.7%, 1%, 2%, and 5%) and 4 out of 36 isolates (two Gram positive and two Gram negative bacteria) were selected for further identification. 16S rRNA gene sequencing revealed that the isolates are related to Bacillus velezensis, Bacillus flexus, Pseudomonas brenneri and Pseudomonas azotoforman. Oil degrading potential of these bacteria was characterized by GC-MS analysis of degradation of oil components in crude oil as well as engine oil. We found that one (2, 6, 10, 14-Tetramethylpentadecane) out of 42 components in the crude oil was fully eliminated and the other oil components were reduced. In addition, 26 out of 42 oil components in the engine oil, were fully eliminated and the rest were amended. Taken together, these studies identify that B. velezensis, B. flexus, P. brenneri and P. azotoforman have high oil degrading potential, which may be useful for degradation of oil pollutants and other commercial applications.

Neste estudo, bactérias degradadoras de óleo descobertas em peixes que vivem perto dos portos de petróleo em Karachi, no Paquistão, foram caracterizadas. As bactérias isoladas da pele, guelras e intestinos dos peixes podem consumir petróleo bruto como fonte de carbono e energia. No total, 36 isolados foram testados usando Agar Nutriente (NA) e meio MSA com diferentes concentrações de óleo bruto (0,2%, 0,5%, 0,7%, 1%, 2% e 5%) e 4 de 36 isolados (dois Gram positivos e duas bactérias Gram negativas) foram selecionadas para posterior identificação. O sequenciamento do gene 16S rRNA revelou que os isolados estão relacionados a Bacillus velezensis, Bacillus flexus, Pseudomonas brenneri e Pseudomonas azotoforman. O potencial de degradação do óleo dessas bactérias foi caracterizado pela análise de GC-MS da degradação dos componentes do óleo no óleo cru, bem como no óleo do motor. Descobrimos que um (2, 6, 10, 14-tetrametilpentadecano) de 42 componentes do óleo cru foi totalmente eliminado e os outros componentes do óleo foram reduzidos. Além disso, 26 dos 42 componentes do óleo do motor foram totalmente eliminados e o restante corrigido. Juntos, esses estudos identificam que B. velezensis, B. flexus, P. brenneri e P. azotoforman têm alto potencial de degradação de óleo, o que pode ser útil para a degradação de poluentes de óleo e outras aplicações comerciais.

Effect of calcium on Pseudomonas aeruginasa and Bacillus cereus metabolites / Efeito do cálcio nos metabólitos de Pseudomonas aeruginasa e Bacillus cereus

The effects of Calcium (Ca+2) on virulence and some parameters should be analyzed in this study. Pseudomonas aeruginosa Gram (-) and Bacillus cereus Gram (+) were used. Both bacteria are soil bacteria. In this study; the effect of Ca+2 on protease, amylase, LasB elastolytic assay, H2O2, pyorubin and biofilm on metabolites of these bacteria were investigated during 24 hour time. In this study, the effect of Ca+2 on the production of some secondary metabolites on P. aeruginosa and B. cereus was investigated and presented for the first time by us.

Os efeitos do cálcio (Ca+2) na virulência e alguns parâmetros devem ser analisados neste estudo. Pseudomonas aeruginosa Gram (-) e Bacillus cereus Gram (+) foram usados. Ambas as bactérias são bactérias do solo. Neste estudo, o efeito do Ca+2 sobre a protease, amilase, ensaio elastolítico LasB, H2O2, piorubina e biofilme nos metabólitos dessas bactérias foram investigados durante 24 horas. Neste estudo, o efeito do Ca+2 na produção de alguns metabólitos secundários em P. aeruginosa e B. cereus foi investigado e apresentado pela primeira vez por nós.

Endophytic bacteria Bacillus safensis and Pseudomonas hibiscicola and their ability to increase rice seedling growth

Endophytic bacteria Bacillus safensis RS95 and Pseudomonas hibiscicola RS121 were evaluated for their ability to promote the growth of rice seedlings and produce indole-acetic acid (IAA) and siderophores and to solubilize phosphates. 'Guri' rice seeds were immersed in bacterial endophyte cell suspensions (separated and two-strain mixed), as well as in Escherichia coli DH5α, phosphate-buffered saline (PBS) and water treatments (negative controls). Seeds were sown on agar-water in Petri plates placed vertically at an angle of 65°. The ability of plant growth-promoting endophytic bacteria (PGPEB) to produce IAA and siderophores was determined by Salkowski colorimetric and chrome azurol S (CAS) assays, respectively. Mineral phosphate solubilization activity was calculated by inoculating the endophytes onto medium containing insoluble phosphate. PGPEB showed a positive effect on the growth of rice seedlings, causing a mean growth of shoots and primary-roots of 60 and 67%, respectively. Bacterial strains also showed positive traits for IAA and siderophore production, as well as phosphate-solubilization activity

Producción de plásticos biodegradables a partir de bacterias de hábitats salinos aisladas de la Laguna de Ayarza / Production of biodegradable plastics from saline habitats bacteria isolated from Laguna de Ayarza

La contaminación por plásticos petroquímicos es una grave amenaza para el medio ambiente que requiere im-plementar alternativas como los bioplásticos para lograr un desarrollo sostenible. Los polihidroxialcanoatos (PHA) son polímeros utilizados para la producción de plásticos biodegradables y que han llamado la atención como sustitutos de los plásticos de base fósil. Sin embargo, el costo de producción de los PHA constituye una barrera para su producción industrial a gran escala. Las de bacterias de hábitats salinos son microorganismos prometedores para la síntesis de PHA debido a sus características tales como altos requisitos de salinidad que previenen la contaminación microbiana, la alta presión osmótica intracelular que permite una fácil lisis celular para purificar los PHA y la capacidad para usar un amplio espectro de sustratos. La presente investigación planteó determinar las cepas nativas de bacterias halófilas y halotolerantes de la Laguna de Ayarza capaces de producir PHA, establecer la capacidad que tienen de utilizar residuos agrícolas para la producción de PHA y determinar su eficiencia. Esto se logró a través de la inoculación de las cepas productoras de PHA en medios de fermentación con pulpa de café, cáscaras de plátanos y salvado de trigo lo que permitió determinar las cepas más eficientes. Se encontró que las bacterias productoras de PHA pertenecen a las especies: Alcaligenes faecalis, Bacillus idriensis, Bacillus megaterium, Exiguobacterium acetylicum, E. aurantiacum, Pseudomonas cuatrocienegasensis y Sta-phylococcus capitis y que las cepas AP21-14, AP21-10 y AP21-03 mostraron los mejores resultados que podrían ser prometedores para la producción a nivel industrial.

Pollution by petrochemical plastics is a serious threat to the environment that requires the implementation of al-ternatives such as bioplastics to achieve sustainable development. Polyhydroxyalkanoates (PHAs) are polymers used for the production of biodegradable plastics and have drawn attention as substitutes for fossil-based plastics. However, the cost of producing PHAs constitutes a barrier to their large-scale industrial production. Bacteria from saline environments bacteria are promising microorganisms for PHA synthesis due to their characteristics such as high salinity requirements that prevent microbial contamination, high intracellular osmotic pressure that allows easy cell lysis to purify PHAs, and the ability to use a broad spectrum of substrates. This research project aimed to determine the native strains of halophilic and halotolerant bacteria from Laguna de Ayarza capable of producing PHA, establish their ability to use agricultural residues for the production of PHA, and determine their efficiency. This was achieved through the inoculation of the PHA-producing strains in fermentation media with coffee pulp, banana peels and wheat bran, which allowed determining the most efficient strains. It was found that the PHA-producing bacteria belong to the species: Alcaligenes faecalis, Bacillus idriensis, Bacillus mega-terium, Exiguobacterium acetylicum, E. aurantiacum, Pseudomonas cuatrocienegasensis and Staphylococcus capitis and that the strains AP21-14, AP21-10 and AP21-03 showed the best results that could be promising for production at an industrial level.

Biomineralization of lithium nanoparticles by Li-resistant Pseudomonas rodhesiae isolated from the Atacama salt flat

BACKGROUND: The Atacama salt flat is located in northern Chile, at 2300 m above sea level, and has a high concentration of lithium, being one of the main extraction sites in the world. The effect of lithium on microorganism communities inhabiting environments with high concentrations of this metal has been scarcely studied. A few works have studied the microorganisms present in lithium-rich salt flats (Uyuni and Hombre Muerto in Bolivia and Argentina, respectively). Nanocrystals formation through biological mineralization has been described as an alternative for microorganisms living in metal-rich environments to cope with metal ions. However, bacterial lithium biomineralization of lithium nanostructures has not been published to date. In the present work, we studied lithium-rich soils of the Atacama salt flat and reported for the first time the biological synthesis of Li nanoparticles. RESULTS: Bacterial communities were evaluated and a high abundance of Cellulomonas, Arcticibacter, Mucilaginibacter, and Pseudomonas were determined. Three lithium resistant strains corresponding to Pseudomonas rodhesiae, Planomicrobium koreense, and Pseudomonas sp. were isolated (MIC > 700 mM). High levels of S2− were detected in the headspace of P. rodhesiae and Pseudomonas sp. cultures exposed to cysteine. Accordingly, biomineralization of lithium sulfide-containing nanomaterials was determined in P. rodhesiae exposed to lithium salts and cysteine. Transmission electron microscopy (TEM) analysis of ultrathin sections of P. rodhesiae cells biomineralizing lithium revealed the presence of nanometric materials. Lithium sulfide-containing nanomaterials were purified, and their size and shape determined by dynamic light scattering and TEM. Spherical nanoparticles with an average size < 40 nm and a hydro-dynamic size ~ 44.62 nm were determined. CONCLUSIONS: We characterized the bacterial communities inhabiting Li-rich extreme environments and reported for the first time the biomineralization of Li-containing nanomaterials by Li-resistant bacteria. The biosynthesis method described in this report could be used to recover lithium from waste batteries and thus provide a solution to the accumulation of batteries.

Susceptibilidad antimicrobiana en Pseudomona spp, en el Hospital General Docente Cuenca-Ecuador / Antimicrobial susceptibility in Pseudomona spp, in the General Teaching Hospital Cuenca-Ecuador / Suscetibilidade antimicrobiana em Pseudomona spp, no Hospital Geral Escola Cuenca-Ecuador

La Pseudomona aeruginosa es un patógeno nosocomial por excelencia; la aparición de cepas multidrogoresistentes (MDR) y extremodrogoresistentes (XDR) cada vez es más frecuente y genera gran preocupación; el uso indiscriminado de antibióticos ha ocasionado esta situación. El objetivo de este estudio fue conocer los diferentes perfiles de resistencia que presentan los aislados objetos de estudio según su procedencia, ya sea a nivel intrahospitalario o de origen comunitario además de caracterizar los principales mecanismos de resistencia y antibiotipos. La presente investigación fue de tipo documental, descriptiva, de corte transversal, para lo cual se utilizó los datos acumulados de susceptibilidad reportados por el departamento de microbiología del Hospital General Docente durante el enero de 2015 hasta diciembre de 2019. Se encontró que en este hospital existe una mayor prevalencia de resistencia a aminoglucósidos (20-25%), fluoroquinolonas (22-25%) y carbapenémicos (19-21%); siendo P. aeruginosa la especie más prevalente. Respecto al tipo de carbapenemasas que son las de interés clínico por su limitante opción terapéutica, se identificó una cepa con fenotipo compatible con metalobetalamasa, se presume que el mecanismo de resistencia predominante fue impermeabilidad. No se identificaron cepas PDR, pero el 21,6% se mostraron con un perfil MDR, aisladas principalmente en los servicios hospitalarios al igual que las cepas XDR.

Pseudomonas aeruginosa is a nosocomial pathogen par excellence; the appearance of multidrug resistant (MDR) and extreme drug resistant (XDR) strains is becoming more frequent and is causing great concern; the indiscriminate use of antibiotics has caused this situation. The objective of this study was to know the different resistance profiles presented by the isolated objects of study according to their origin, either at the intrahospital level or of community origin, in addition to characterizing the main resistance mechanisms and antibiotypes. The present investigation was of a documentary, descriptive, cross-sectional type, for which the accumulated susceptibility data reported by the microbiology department of the General Teaching Hospital from January 2015 to December 2019 was used. It was found that in this hospital there is a higher prevalence of resistance to aminoglycosides (20-25%), fluoroquinolones (22-25%) and carbapenems (19-21%); being P. aeruginosa the most prevalent species. Regarding the type of carbapenemases that are of clinical interest due to their limiting therapeutic option, a strain with a phenotype compatible with metallobetalamase was identified, it is presumed that the predominant resistance mechanism was impermeability. No PDR strains were identified, but 21.6% were shown with an MDR profile, isolated mainly in hospital services as well as the XDR strains.

Pseudomonas aeruginosa é um patógeno nosocomial por excelência; o aparecimento de cepas multirresistentes (MDR) e extremamente resistentes aos medicamentos (XDR) está se tornando mais frequente e causando grande preocupação; o uso indiscriminado de antibióticos tem causado essa situação. O objetivo deste estudo foi conhecer os diferentes perfis de resistência apresentados pelos objetos isolados de estudo de acordo com sua origem, seja em nível intra-hospitalar ou de origem comunitária, além de caracterizar os principais mecanismos de resistência e antibióticos. A presente investigação foi do tipo documental, descritiva, transversal, para a qual foram utilizados os dados de suscetibilidade acumulada reportados pelo departamento de microbiologia do Hospital Geral Universitário no período de janeiro de 2015 a dezembro de 2019. Verificou-se que neste hospital há maior prevalência de resistência aos aminoglicosídeos (20-25%), fluoroquinolonas (22-25%) e carbapenêmicos (19-21%); sendo P. aeruginosa a espécie mais prevalente. Em relação aos tipos de carbapenemases de interesse clínico devido à sua opção terapêutica limitante, foi identificada uma cepa com fenótipo compatível com metalobetalamase, presume-se que o mecanismo de resistência predominante foi a impermeabilidade. Nenhuma cepa PDR foi identificada, mas 21,6% mostraram ter um perfil MDR, isolado principalmente em serviços hospitalares, bem como as cepas XDR.

Calidad microbiológica del aire en un Centro Comunitario de Salud Familiar de Talcahuano, Región del Biobío, Chile / Microbiological air quality in a Community Family Health Center of Talcahuano, Biobío Region, Chile

INTRODUCCIÓN: La calidad del aire en centros de salud es fundamental para resguardar la salud de las personas. En Chile, los Centros Comunitarios de Salud Familiar (CECOSF) son lugares de gran concurrencia de personas, favoreciendo la diseminación de microorganismos. OBJETIVO: Evaluar la calidad microbiológica del aire al interior del CECOSF-Centinela en Talcahuano, Región del Biobío. METODOLOGÍA: Se tomó muestras de aire en seis salas del CECOSF, quincenalmente, entre julio de 2018 y junio de 2019, con el equipo MAS-100 NT, empleando agar tripticasa y agar Sabouraud. Diferentes morfotipos de bacterias y hongos fueron identificados mediante RPC. RESULTADOS: Los recuentos de bacterias y hongos variaron entre 9,1 × 101 - 2,4 × 103 ufc/m3 y 10 - 1,5 × 102 ufc/m3, respectivamente. El aire de la sala de espera presentó los recuentos más altos, tanto para bacterias como hongos (P < 0,05). Se identificó Staphylococcus, Enterococcus, Pseudomonas, Acinetobacter, destacando las especies Staphylococcus aureus y Pseudomonas oryzihabitans, microrganismo este último, descrito actualmente como patógeno nosocomial. Entre los hongos se identificó Aspergillus, Meyerozyma y Rhodotorula. CONCLUSIÓN: Las muestras de aire del CECOSF-Centinela presentan microrganismos de importancia en salud humana. De ahí la necesidad de formular programas de monitoreo más regulares para controlar la calidad del aire al interior de estos establecimientos.

BACKGROUND: Indoor air quality in health centers is essential to protect the health of people. In Chile, the Community Family Health Centers (CECOSF) are places with large attendance of people, favoring the dissemination of microorganisms, and there are no reports of the microbial air loading these health centers. AIM: To evaluate the microbiological indoor air quality in CECOSF-Centinela in Talcahuano, Biobío Region. METHODS: Air samples were taken in 6 rooms of the CECOSF, every 15 days between July 2018 and June 2019, with the MAS-100 NT equipment using trypticase and Sabouraud agars. Different morphotypes of bacteria and fungi were identified by PCR. Results: The bacterial and fungal counts varied between 9.1 × 101 - 2.4 × 103 cfu/m3 and 10 - 1.5 × 102 cfu/m3, respectively. The air in the waiting room presented the highest counts, both for bacteria and fungi (P < 0.05). Staphylococcus, Enterococcus, Pseudomonas, Acinetobacter were identified, highlighting the species Staphylococcus aureus and Pseudomonas oryzihabitans, the latter described as a nosocomial pathogen. Among the fungi, Aspergillus, Meyerozyma and Rhodotorula were identified. CONCLUSION: The indoor air of the CECOSF-Centinela presents microorganisms of importance in human health. Therefore, it is necessary to formulate more regular monitoring programs for the control of air quality inside these health centers.

Caracterización molecular de carbapenemasas en el Perú durante el 2019 / Molecular characterization of carbapenemases in Peru during 2019

RESUMEN La resistencia a los carbapenémicos es un problema de salud pública. Este estudio presenta la identificación de enzimas carbapenemasas en Enterobacteriaceae, Pseudomonas spp. y Acinetobacter spp. presentes en cepas de 30 instituciones prestadoras de servicios de salud del Perú como parte del proceso de control de calidad en diagnósticos. La confirmación fenotípica e identificación enzimática se realizó utilizando la prueba de Blue CARBA y la prueba de sinergia con discos de ácido fenilborónico y ácido etilendiaminotetraacético/ácido mercaptoacético de sodio. Se identificaron 185 cepas con carbapenemasas: 78 en Enterobacteriaceae, 61 en P. aeruginosa y 46 en Acinetobacter spp. Los tipos de carbapenemasas identificadas fueron: blaKPC, blaNDM, blaIMP, blaVIM, blaOXA-23, blaOXA-24, blaOXA-51 y la coproducción de blaVIM/IMP. Es importante reforzar la promoción del uso racional de antimicrobianos y la vigilancia epidemiológica en los nosocomios del país.

ABSTRACT Resistance to carbapenems is a public health problem. This study presents the identification of carbapenemase enzymes in Enterobacteriaceae, Pseudomonas spp. and Acinetobacter spp. present in strains from 30 institutions that provide health services in Peru as part of the quality control process in diagnoses. Phenotypic confirmation and enzymatic identification were performed using the Blue CARBA test and the synergy test with phenylboronic acid and ethylenediaminetetraacetic acid/sodium mercaptoacetic acid discs. 185 strains with carbapenemases were identified: 78 in Enterobacteriaceae, 61 in P. aeruginosa and 46 in Acinetobacter spp. The types of carbapenemases identified were: blaKPC, blaNDM, blaIMP, blaVIM, blaOXA-23, blaOXA-24, blaOXA-51 and the blaVIM/IMP co-production. It is important to strengthen the promotion of the rational use of antimicrobials and epidemiological surveillance in the country's hospitals.

Caracterización molecular de carbapenemasas en el Perú durante el 2019 / Molecular characterization of carbapenemases in Peru during 2019

RESUMEN La resistencia a los carbapenémicos es un problema de salud pública. Este estudio presenta la identificación de enzimas carbapenemasas en Enterobacteriaceae, Pseudomonas spp. y Acinetobacter spp. presentes en cepas de 30 instituciones prestadoras de servicios de salud del Perú como parte del proceso de control de calidad en diagnósticos. La confirmación fenotípica e identificación enzimática se realizó utilizando la prueba de Blue CARBA y la prueba de sinergia con discos de ácido fenilborónico y ácido etilendiaminotetraacético/ácido mercaptoacético de sodio. Se identificaron 185 cepas con carbapenemasas: 78 en Enterobacteriaceae, 61 en P. aeruginosa y 46 en Acinetobacter spp. Los tipos de carbapenemasas identificadas fueron: blaKPC, blaNDM, blaIMP, blaVIM, blaOXA-23, blaOXA-24, blaOXA-51 y la coproducción de blaVIM/IMP. Es importante reforzar la promoción del uso racional de antimicrobianos y la vigilancia epidemiológica en los nosocomios del país.

ABSTRACT Resistance to carbapenems is a public health problem. This study presents the identification of carbapenemase enzymes in Enterobacteriaceae, Pseudomonas spp. and Acinetobacter spp. present in strains from 30 institutions that provide health services in Peru as part of the quality control process in diagnoses. Phenotypic confirmation and enzymatic identification were performed using the Blue CARBA test and the synergy test with phenylboronic acid and ethylenediaminetetraacetic acid/sodium mercaptoacetic acid discs. 185 strains with carbapenemases were identified: 78 in Enterobacteriaceae, 61 in P. aeruginosa and 46 in Acinetobacter spp. The types of carbapenemases identified were: blaKPC, blaNDM, blaIMP, blaVIM, blaOXA-23, blaOXA-24, blaOXA-51 and the blaVIM/IMP co-production. It is important to strengthen the promotion of the rational use of antimicrobials and epidemiological surveillance in the country's hospitals.

Fascitis necrotizante / Necrotizing Fasciitis

RESUMEN Introducción: La fascitis necrotizante tiene origen polimicrobiano, se caracteriza por necrosis extensa acompañada de formación gaseosa en el tejido subcutáneo y fascia superficial. Objetivo: Describir el manejo terapéutico exitoso de dos casos afectos de fascitis necrotizante. Caso clínico: Dos pacientes tratados en el Hospital General Docente "Abel Santamaría Cuadrado", mujeres de la tercera y cuarta década de la vida, con área extensa de celulitis y necrosis de progreso rápido, necesidad de tratamiento quirúrgico y cultivos positivos de Pseudomona y Escherichia coli respectivamente, con repercusión clínica sistémica. Conclusiones: La fascitis necrotizante es una enfermedad de ascenso rápido y etiología variada, que pone en riesgo la vida del paciente, el diagnóstico debe sospecharse tempranamente ofreciendo intervención oportuna y agresiva, el manejo debe ser multidisciplinario(AU)

ABSTRACT Introduction: Necrotizing fasciitis has a polymicrobial origin. It is characterized by extensive necrosis accompanied by gas formation in the subcutaneous tissue and superficial fascia. Objective: To describe the successful therapeutic management of two cases with necrotizing fasciitis. Clinical case: Two patients treated at Abel Santamaría Cuadrado General Teaching Hospital, women at the third and fourth decades of life, with extensive area of cellulitis and rapidly progressing necrosis, need for surgical treatment and positive cultures of Pseudomonas and Escherichia coli, respectively, with systemic clinical repercussions. Conclusions: Necrotizing fasciitis is a disease of rapid progression and varied etiology, which puts the patient's life at risk; the diagnosis must be suspected early, offering timely and aggressive intervention, and management must be multidisciplinary(AU)

Colistina en el tratamiento de infecciones por pseudomonas aeruginosa y acinetobacter baumannii extensivamente resistentes (XDR) en un hospital de tercer nivel / Colistin-based treatment for extensively drug resistant (XDR) Pseudomonas aeruginosa and Acinetobacter baumannii infection at a third level hospital

Resumen Objetivo: Describir la respuesta clínica y mortalidad general de Colistina en infecciones por Pseudomonas XDR y Acinetobacter XDR en el Hospital Nacional Arzobispo Loayza in Lima, Peru. Métodos: Estudio observacional, descriptivo y retrospectivo. Se incluyeron los registros de pacientes > 18 años, desde junio del 2014 a junio del 2016, que tuvieron infección por Pseudomonas XDR o Acinetobacter XDR confirmada por cultivo, y que recibieron colistina. Se realizó análisis univariado de las características generales de los pacientes; un análisis bivariado con test de Chi2 , t-student o ANOVA según corresponda, y además se describió los factores asociados a mortalidad. Resultados. Se incluyeron 56 registros de pacientes, la mediana de la edad fue 46,5 [31,5 a 63,5]. El 48,2% tuvo un cultivo positivo para Pseudomonas XDR y el 51,8% para Acinetobacter XDR. La respuesta clínica favorable fue 85,7% a los 15 días y de 78,6% a los 30 días. La mortalidad intrahospitalaria a los 30 días fue 21,4%, la mortalidad en UCI fue de 30,8% y la nefrotoxicidad fue de 5,4%. Conclusiones. Colistina combinada con otro antimicrobiano tuvo una respuesta clínica favorable en infección por Pseudomonas XDR o Acinetobacter XDR.

Abstract Objective: To describe the clinical response and overall mortality of Colistin in infections by Pseudomonas XDR and Acinetobacter XDR at the Hospital Nacional Arzobispo Loayza in Lima, Peru. Methods: Observational, descriptive, retrospective study. Records of all patients > 18 years old, from June 2014 to June 2016, who had infection by Pseudomonas XDR or Acinetobacter XDR confirmed by culture, and who received colistin, were included. A univariate analysis of the general characteristics of the patients was performed; a bivariate analysis with a Chi2, t-student or ANOVA test as appropriate, and the factors associated with mortality were also determined. Results: 56 patient records were included; the median age was 46,5 [31,5 to 63,5]. The Culture was positive for Pseudomonas XDR in 48,2% and for Acinetobacter XDR in 51,8%. The favorable clinical response was 85,7% at 15 days and 78,6% at 30 days. In-hospital mortality at 30 days was 21,4%, ICU mortality was 30,8% and nephrotoxicity was 5,4%. Conclusions: Colistin combined with another antimicrobial had a favorable clinical response in infection with Pseudomonas XDR and Acinetobacter XDR.

Detection of carbapenem hydrolyzing enzyme and extendedspectrum beta-lactamase in clinical isolates of Enterobacteriaceae and Pseudomonaceae / Detecção de enzimas hidrolizantes de carbapenemas e beta-lactamases de espectro estendido em isolados clínicos de Enterobacteriaceae e Pseudomonaceae

Objective: Characterize isolates of enterobacterias and pseudomonas based on their resistance to the antibiotics. Methods: This study was conducted with 44 samples from various species from the Enterobacteriaceae and Pseudomonaceae family and they were submitted to the Modified Hodge Test and Extended Spectrum Beta-Lactamase (ESBL) test. Results: From the 44 analyzed samples nine produced ESBL and ten produced some kind of carbapenemase. Conclusion: In total, 38,6% of the samples showed an increased in the incidence of this resistance in the last few years given that before 2001 there was not a single carbapenemase described. This fact alarms patients immunosuppressed or hospitalized since they colonize our digestive tract and can cause an infection given the opportunity.

Objetivo: Caracterizar isolados de enterobactérias e pseudomonas em relação a sua resistência aos antimicrobianos. Métodos: O estudo foi realizado com 44 amostras de várias espécies das famílias Enterobacteriaceae e Pseudomonaceae, as quais foram submetidas aos testes de Hodge Modificado e Beta-Lactamase de Espectro Estendido (ESBL). Resultados: Das 44 amostras analisadas nove são produtoras de ESBL e dez são produtoras de carbapenemase. Conclusão: No total, 38,6% das amostras apresentaram algum tipo de resistência às ESBL e carbapenemases, e esse número mostra um aumento na incidência dessas resistências nos últimos anos já que, antes de 2001, não haviam sido descritas as enzimas car­­­ba­­­penemases. Esse fato é alarmante para pacientes imunossuprimidos ou hospitalizados uma vez que as enterobactérias colonizam nosso trato digestivo e podem causar uma infecção se dada a oportunidade.

Neonatal infection and passive acquisition of serum total IgG and reactive with Streptococcus B, anti-LPS of Klebsiella spp and Pseudomonas spp antibodies in twins

SUMMARY OBJECTIVE To describe the concentration of total and specific IgG antibodies anti-Streptococcus B, anti-lipopolysaccharide of Klebsiella spp, and anti-lipopolysaccharide of Pseudomonas spp in the umbilical cord of newborn(NB) twins and to analyze the association between neonatal infection and antibody concentration in the umbilical cord blood. METHODS A prospective cross-sectional study of a cohort of NB twins admitted during the period of 20 months. Patients with malformations and mothers with infection were excluded. Variables analyzed: gestational age(GA); birth weight(BW); antibody concentrations in umbilical cord blood; infection episodes. We used the paired Student t-test, Spearman correlation, and generalized estimation equation. RESULTS 57 pairs of twins were included, 4 excluded, making the sample of 110 newborns. GA=36±1.65weeks and BW=2304.8±460g(mean±SD). Antibody concentrations in twins(mean±SD): total IgG=835.71±190.73mg/dL, anti-StreptococcusB IgG=250.66±295.1 AU/mL, anti-lipopolysaccharide of Pseudomonas spp IgG=280.04±498.66 AU/mL and anti-lipopolysaccharide of Klebsiella spp IgG=504.75±933.93 AU/mL. There was a positive correlation between maternal antibody levels and those observed in newborns(p <0.005). The transplacental transfer of maternal total IgG and anti-LPS Pseudomonas IgG antibodies was significantly lower at NB GA <34 weeks(p <0.05). Five newborns were diagnosed with an infection. Infants with infection had significantly lower total IgG concentration(p <0.05). CONCLUSION This study showed a positive correlation between maternal and newborn antibodies levels. In infants younger than 34 weeks there is less transfer of total IgG and anti-LPS Pseudomonas IgG. The highest incidence of infection in the newborn group who had significantly lower total IgG serum antibodies reinforces the importance of anti-infectious protection afforded by passive immunity transferred from the mother.

RESUMO OBJETIVOS Descrever o título de anticorpos IgG total e específico anti-Streptococcus B, anti-lipopolissacarídeos(LPS) de Klebsiella e Pseudomonas no cordão umbilical em gêmeos e analisar a possível associação entre os títulos desses anticorpos e a ocorrência de infecção. MÉTODOS Estudo prospectivo transversal de uma coorte de recém-nascidos (RN) gemelares em 20 meses. Excluídos: malformação, infecção congênita ou materna. Variáveis estudadas: idade gestacional(IG); peso de nascimento(PN); título de anticorpos e episódios de infecção. Foram utilizados testes t-Student pareado, correlação de Spearman e equações de estimação generalizadas. RESULTADOS Elegíveis 59 pares de gêmeos, excluídos 4 e incluídos 55 pares (n=110RN). A IG foi 36±1,65semanas e o PN foi 2304,8±460g (média±DP). Concentrações de anticorpos dos RN(média±DP): IgG total=835,71±190,73 mg/dL, IgG anti-Streptococcus B=295,1±250,66 UA/mL, IgG anti-LPS Pseudomonas=280,04±498,66 UA/mL e IgG anti-LPS Klebsiella=504,75± 933,93UA/mL. Houve correlação positiva entre níveis de anticorpos maternos e aqueles observados nos RN (p<0,005). A transferência transplacentária de anticorpos maternos IgG total e IgG anti-LPS Pseudomonas foi significativamente menor em RN IG < 34semanas (p<0,05). Foram diagnosticados 5 RN com infecção. Os RN que apresentaram infecção tinham concentração de IgG total significativamente menor (p<0,05). CONCLUSÕES Na população estudada existe correlação entre os anticorpos maternos e os níveis de anticorpos no RN. Nos gêmeos menores que 34 semanas há menor transferência de IgG total e IgG anti-LPS Pseudomonas. Nos RN com infecção a concentração de IgG total é significativamente menor, o que demonstra a maior vulnerabilidade e risco de infecção dessa população e a importância da imunidade passiva transferida pela placenta.

Utilization of agroindustrial byproducts for the production of lipase by a new strain of Pseudomonas sp / Utilização de subprodutos agroindustriais para a produção de lipase por uma nova cepa de Pseudomonas sp

This study aimed to evaluate the production of lipases by a new strain of Pseudomonas sp. using fermentation medium containing byproducts of poultry meat or soybean oil industry. The results indicate that chicken fat and soybean gum induced 48.3 U/mL and 93.3 of lipase activity, respectively. However, the higher lipase production was obtained when the crude lecithin gum was used, archiving 272.6 U/ml of activity after 24 hours. The partial biochemical characterization of the enzyme showed that the optimum reaction conditions were pH 9.0 and 35 °C. The enzyme was stable at temperatures between 25 to 75 °C and at pH from 6 to 9. The enzyme also showed good stability in organic solvents, such as acetronitrile, hexane, ethanol and isopropanol. This study indicates that the byproducts tested are promising for the production of lipase and can contribute to the reduction of enzymatic production costs on a large scale, increase the value of these byproducts and reduce potential environmental impacts caused by its accumulation in nature.(AU)

Este estudo teve como objetivo avaliar a produção de lipases por uma nova cepa de Pseudomonas sp. utilizando meio de fermentação contendo subprodutos de industrialização de carne de frango e óleo de soja. Os resultados indicaram que a gordura de frango e a goma de soja induziram 48,3 U/mL e 93,3 U/ml de atividade lipásica, respectivamente. No entanto, a produção de lipase mais elevada foi obtida quando a goma de lecitina bruta foi utilizada, induzindo 272,6 U/ml de atividade após 24 horas. A caracterização bioquímica parcial da enzima mostrou que as condições de reação ótimas foram de pH 9,0 e 35 °C. A enzima foi estável nas temperaturas entre 25 a 75 °C e pH de 6 a 9. A enzima mostrou boa estabilidade em solventes orgânicos, tais como acetonitrila, hexano, etanol e isopropanol. Este estudo indicou que os subprodutos testados são promissores para a produção de lipase e podem contribuir para a redução dos custos de produção enzimática em larga escala, aumentar o valor desses subprodutos e reduzir potenciais impactos ambientais causados por sua acumulação na natureza.(AU)