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1.
Environ Pollut ; 347: 123689, 2024 Apr 15.
Article in English | MEDLINE | ID: mdl-38460587

ABSTRACT

Ulva spp. are tolerant to salinity variations and exhibit easy acclimation, playing an essential role in the depollution of aquatic ecosystems precisely due to their high efficiency in absorbing and accumulating nutrients. For this reason, Ulva spp. becomes an attractive solution for recovering areas that suffer the impacts of problems such as the eutrophication of anthropogenic origin. In addition to being a promising alternative for the blue bioeconomy, it can contribute to the sustainability of economic activities in coastal areas. Therefore, the present study aimed to develop and elucidate the behavior of Ulva ohnoi using predictive surface response models. The algae were grown under different concentrations of nutrient and salinity levels, as predicted by the experimental design, and it was evaluated according to the potential of the biomass to absorb the nutrients, as well as its photosynthetic performance and biochemical parameters. Our study confirmed the high efficiency and preference of Ulva ohnoi in the absorption of nitrogen dissolved in the medium in the form of NH4+ and that salinity is an essential factor in the dynamics and speed of ammonium absorption. The absorption of orthophosphate by U. ohnoi is reverted to the culture medium when subjected to long-term cultivation. This process was more intense because of low salinity, even at conditions of availability of the compound. The 3D-models of response surfaces elucidate the behavior of Ulva ohnoi, attributing a correlation between nutrient availability and salinity and the biological behavior of the species. In view of what is exposed by these models, as well as the effects of saline distribution along the Lagoon, the following regions of the lagoon are suggested: Center-North, Center and South - as potential areas for the implementation of bioremediation projects with Ulva ohnoi.


Subject(s)
Ecosystem , Ulva , Biodegradation, Environmental , Photosynthesis , Biomass
2.
Front Cell Infect Microbiol ; 13: 1247329, 2023.
Article in English | MEDLINE | ID: mdl-37780856

ABSTRACT

RNA-binding proteins (RBPs) are essential for regulating RNA metabolism, stability, and translation within cells. Recent studies have shown that RBPs are not restricted to intracellular functions and can be found in extracellular vesicles (EVs) in different mammalian cells. EVs released by fungi contain a variety of proteins involved in RNA metabolism. These include RNA helicases, which play essential roles in RNA synthesis, folding, and degradation. Aminoacyl-tRNA synthetases, responsible for acetylating tRNA molecules, are also enriched in EVs, suggesting a possible link between these enzymes and tRNA fragments detected in EVs. Proteins with canonical RNA-binding domains interact with proteins and RNA, such as the RNA Recognition Motif (RRM), Zinc finger, and hnRNP K-homology (KH) domains. Polyadenylate-binding protein (PABP) plays a critical role in the regulation of gene expression by binding the poly(A) tail of messenger RNA (mRNA) and facilitating its translation, stability, and localization, making it a key factor in post-transcriptional control of gene expression. The presence of proteins related to the RNA life cycle in EVs from different fungal species suggests a conserved mechanism of EV cargo packing. Various models have been proposed for selecting RNA molecules for release into EVs. Still, the actual loading processes are unknown, and further molecular characterization of these proteins may provide insight into the mechanism of RNA sorting into EVs. This work reviews the current knowledge of RBPs and proteins related to RNA metabolism in EVs derived from distinct fungi species, and presents an analysis of proteomic datasets through GO term and orthology analysis, Our investigation identified orthologous proteins in fungal EVs on different fungal species.


Subject(s)
Extracellular Vesicles , RNA , Animals , RNA/analysis , Proteomics , RNA, Messenger/metabolism , Extracellular Vesicles/metabolism , RNA-Binding Proteins/metabolism , Mammals/genetics
3.
Biomedicines ; 11(6)2023 May 24.
Article in English | MEDLINE | ID: mdl-37371610

ABSTRACT

Klebsiella pneumoniae is a nosocomial pathogen and an important propagator of multidrug-resistant (MDR) and extensively drug-resistant (XDR) strains. Like other Gram-negative bacteria, they secrete outer membrane vesicles (OMVs) that distribute virulence and resistance factors. Here, we subjected a K. pneumoniae-XDR to subinhibitory concentrations of meropenem, amikacin, polymyxin B, and a combination of these agents to evaluate changes in the protein cargo of OMVs through liquid chromatography-tandem mass spectrometry (LC-MS/MS). Genome sequencing of the clinical isolate K. pneumoniae strain HCD1 (KpHCD1) revealed the presence of 41 resistance genes and 159 virulence factors. We identified 64 proteins in KpHCD1-OMVs modulated with different antibiotic treatments involved in processing genetic information, environmental information, cell envelope formation, energy metabolism, and drug resistance. The OMV proteome expression profile suggests that OMVs may be associated with pathogenicity, survival, stress response, and resistance dissemination.

4.
Arq. ciências saúde UNIPAR ; 27(5): 2967-2980, 2023.
Article in English | LILACS-Express | LILACS | ID: biblio-1435096

ABSTRACT

The study analyzed the profile of Canicross practitioners in Brazil. A semi- structured questionnaire consisting of 33 questions was used: seven related to the handler and 26 to the dogs. Results: Of the total handlers, 53.3% are women, 64% have practiced the sport for at least 5 years and 52.3% trained with a personal trainer. Of the dogs, 62.6% were females, 60% were between one and four years old and the Mixed Breeds were the majority with 34.6%; as for the health of the animals, 80% of the handlers stated that they did not carry out veterinary monitoring aiming at the Canicross. 6.6% of the animals had sports-related injuries and 80% of these cases received veterinary treatment. It was clear that handlers know strategies to prevent and / or treat injuries caused by the sport, however this is not reflected in dogs. The unprecedented nature of the work will help handlers, veterinarians and sports lovers to draw up protocols so that dogs can practice Canicross safely.


O estudo analisou o perfil dos praticantes de Canicross no Brasil. Foi utili- zado um questionário semiestruturado composto por 33 questões, sendo sete relacionadas ao condutor e 26 aos cães. Resultados: Do total de manipuladores, 53,3% são mulheres, 64% praticam o esporte há pelo menos 5 anos e 52,3% treinam com personal trainer. Dos cães, 62,6% eram fêmeas, 60% tinham entre um e quatro anos e os sem raça definida eram a maioria com 34,6%; quanto à saúde dos animais, 80% dos tratadores afirmaram não realizar acompanhamento veterinário visando o Canicross. 6,6% dos animais tiveram lesões esportivas e 80% desses casos receberam tratamento veterinário. Ficou claro que os tratadores conhecem estratégias para prevenir e/ou tratar lesões causadas pelo esporte, porém isso não se reflete nos cães. O caráter inédito do trabalho ajudará tratadores, veterinários e esportistas a traçarem protocolos para que os cães possam praticar Cani- cross com segurança.


El estudio analizó el perfil de los practicantes de Canicross en Brasil. Se utilizó un cuestionario semiestructurado compuesto por 33 preguntas, siendo siete relaci- onadas con el conductor y 26 con los perros. Resultados: Del total de manejadores, 53,3% son mu-lheres, 64% practican el deporte hace por lo menos 5 años y 52,3% entrenan con trai-ner personal. De los perros, 62,6% eran hembras, 60% tenían entre uno y cuatro años y los sin raza definida eran la mayoría con 34,6%; en cuanto a la salud de los animales, 80% de los manejadores afirmaron no realizar acompañamiento veterinario con vistas al Canicross. El 6,6% de los animales presentaron lesiones deportivas y el 80% de estos casos recibieron tratamiento veterinario. Quedó claro que los cuidadores conocen estra- tegias para prevenir y/o tratar lesiones causadas por el deporte, sin embargo esto no se refleja en los perros. El carácter inédito del trabajo aju-dará a cuidadores, veterinarios y deportistas a trazar protocolos para que los perros puedan practicar Canicross con segu- ridad.

5.
JACS Au ; 2(6): 1306-1312, 2022 Jun 27.
Article in English | MEDLINE | ID: mdl-35783170

ABSTRACT

We report improvement in the perovskite solar cell efficiency and stability after passivation with an organic molecule decorated with two anilinium cations. We compare this salt with its neutral analog and found that the change in the electron density distribution upon protonation and the presence of the halide anion are key to explaining the better passivation ability of the salt. In addition, we show that the counteranion has a significant impact on the performance of the device.

6.
Acta Crystallogr C Struct Chem ; 78(Pt 6): 332-337, 2022 Jun 01.
Article in English | MEDLINE | ID: mdl-35662132

ABSTRACT

The cocrystal hexamethylenetetramine-tridecanedioic acid (1/1) (HMT-C13), C6H12N4·C13H24O4, was investigated by single-crystal X-ray diffraction techniques at several temperatures during cooling and heating processes. Our results show the formation of two crystalline phases, separated by a large temperature phase co-existence between 290 and 340 K. Phase I, stable above 341 K, presents an orthorhombic structure described in the space group Bmmb, with one N4(CH2)6·C13H22O4 adduct in its asymmetric unit. Phase II, stable below 290 K, presents a monoclinic symmetry described by the space group P21/c, with two N4(CH2)6·C13H22O4 adducts in its asymmetric unit. The phase co-existence is observed both upon cooling and heating, and seems to be related to a complex domain-growth dynamic within the crystal.

7.
Pesqui. vet. bras ; 42: e06990, 2022. tab, ilus
Article in English | LILACS, VETINDEX | ID: biblio-1365240

ABSTRACT

The current techniques used in the disinfection of reused poultry litter, such as lime addition, windrowing and plastic cover on the surface, do not guarantee the elimination of pathogenic microorganisms, causing damage to the environment and animal health. Gram negative bacteria, i.e., Salmonella and Escherichia coli, can be transmitted from one batch to another through reused litter, causing health damage to broilers and humans that consume food contaminated by these agents. Our study assessed the effectiveness of the methods plastic cover on the surface (PCS) and plastic cover on the surface with ammonia gas injection (PCSAI) in the control of Gram negative bacteria. The results obtained, both in laboratory conditions (Experiment 1) and in the field (Experiment 2), demonstrate that the method PCSAI with 0.22% ammonia gas had a significant reduction (P<0.05) of Gram negative bacteria in the period of 48 hours This new methodology for disinfecting poultry litter will allow its reuse in a practical and safe way, improving the preservation of the environment, of the health of broilers and consumers of poultry products.


O reaproveitamento de camas aviárias na criação de frangos de corte é uma prática muito utilizada no Brasil. Essa prática reduz custos de produção e contribui na conservação do meio ambiente. As técnicas atuais utilizadas na desinfecção de camas aviárias reaproveitadas, como adição de cal, enleiramento e lona na superfície, não garantem a eliminação de microrganismos patogênicos porque não geram quantidade suficiente de amônia. O gás amônia, em concentrações elevadas, tem efeito biocida. Bactérias Gram negativas, como as Salmonelas e Escherichia coli, podem ser transmitidas de um lote para outro através do reaproveitamento da cama, ocasionando prejuízos para a saúde das aves e dos humanos que consomem alimentos contaminados por estes agentes. Este trabalho avaliou a eficácia do método lona na superfície com injeção de gás amônia no controle de microrganismos Gram negativos. Os resultados obtidos demostraram que esse método controlou os microrganismos Gram negativos num período de 48 horas em camas de frangos de corte reaproveitadas. Assim, essa nova metodologia de desinfecção de camas de aviário permitirá sua reutilização de forma prática e segura, melhorando a saúde das aves e dos consumidores dos produtos avícolas.


Subject(s)
Animals , Poultry/microbiology , Chickens , Disinfection/methods , Ammonia/therapeutic use , Gram-Negative Bacteria
8.
Article in English | LILACS-Express | LILACS, VETINDEX | ID: biblio-1487698

ABSTRACT

ABSTRACT: The current techniques used in the disinfection of reused poultry litter, such as lime addition, windrowing and plastic cover on the surface, do not guarantee the elimination of pathogenic microorganisms, causing damage to the environment and animal health. Gram negative bacteria, i.e., Salmonella and Escherichia coli, can be transmitted from one batch to another through reused litter, causing health damage to broilers and humans that consume food contaminated by these agents. Our study assessed the effectiveness of the methods plastic cover on the surface (PCS) and plastic cover on the surface with ammonia gas injection (PCSAI) in the control of Gram negative bacteria. The results obtained, both in laboratory conditions (Experiment 1) and in the field (Experiment 2), demonstrate that the method PCSAI with 0.22% ammonia gas had a significant reduction (P 0.05) of Gram negative bacteria in the period of 48 hours This new methodology for disinfecting poultry litter will allow its reuse in a practical and safe way, improving the preservation of the environment, of the health of broilers and consumers of poultry products.


RESUMO: O reaproveitamento de camas aviárias na criação de frangos de corte é uma prática muito utilizada no Brasil. Essa prática reduz custos de produção e contribui na conservação do meio ambiente. As técnicas atuais utilizadas na desinfecção de camas aviárias reaproveitadas, como adição de cal, enleiramento e lona na superfície, não garantem a eliminação de microrganismos patogênicos porque não geram quantidade suficiente de amônia. O gás amônia, em concentrações elevadas, tem efeito biocida. Bactérias Gram negativas, como as Salmonelas e Escherichia coli, podem ser transmitidas de um lote para outro através do reaproveitamento da cama, ocasionando prejuízos para a saúde das aves e dos humanos que consomem alimentos contaminados por estes agentes. Este trabalho avaliou a eficácia do método lona na superfície com injeção de gás amônia no controle de microrganismos Gram negativos. Os resultados obtidos demostraram que esse método controlou os microrganismos Gram negativos num período de 48 horas em camas de frangos de corte reaproveitadas. Assim, essa nova metodologia de desinfecção de camas de aviário permitirá sua reutilização de forma prática e segura, melhorando a saúde das aves e dos consumidores dos produtos avícolas.

9.
REVISA (Online) ; 11(2): 220-231, 2022.
Article in Portuguese | LILACS | ID: biblio-1379418

ABSTRACT

Objetivo: avaliar o efeito da capacitação em primeiros socorros sobre o conhecimento dos professores e agentes de uma unidade escolar. Método: pesquisa quantitativa com delineamento quaseexperimental do tipo pré e pós-teste. A população foi constituída por professores e agentes escolares de uma instituição de ensino no interior do Estado de São Paulo. A coleta de dados foi entre os meses de março e abril de 2022, aplicando-se dois instrumentos: Caracterização sociodemográfica/laboral e questionário de avaliação do conhecimento sobre primeiros socorros. Para analisar os dados empregou-se estatística descritiva, teste de Shapiro Wilk e de Wilcoxon. Resultados: Predominou o gênero feminino (66,7%), média de idade de 43 anos e 66,7% eram casados. 88,9% não participaram de disciplinas em primeiros socorros na formação e 94,5% afirmaram ter presenciado situações acidentes na unidade escolar. Houve aumento no número de acertos das questões relativas a primeiros socorros e melhora em relação aos conceitos (excelente, bom, regular e ruim), com aumento na pontuação do pré-teste para o pós-teste em 3,51 pontos e com a comparação significativa (p<0,001). Conclusão: Os achados mostram que após a aplicação da capacitação em primeiros socorros com professores e os agentes escolares houve aumento de conhecimento, competências e habilidades para atuação na unidade escolar estudada


Objective: to evaluate the effect of training in first aid on the knowledge of teachers and agents of a school unit. Method: quantitative research with a quasi-experimental design of the pre- and post-test type. The population consisted of teachers and school agents from an educational institution in the interior of the State of São Paulo. Data collection took place between March and April 2022, applying two instruments: Sociodemographic/labor characterization and a questionnaire to assess knowledge about first aid. Descriptive statistics, Shapiro Wilk and Wilcoxon tests were used to analyze the data. Results: The female gender predominated (66.7%), mean age was 43 years and 66.7% were married. 88.9% did not participate in first aid courses in training and 94.5% said they had witnessed accident situations at the school unit. There was an increase in the number of correct answers in the questions related to first aid and an improvement in relation to the concepts (excellent, good, fair and bad), with an increase in the pre-test to the post-test by 3.51 points and with the comparison significant (p<0.001). Conclusion: The findings show that after the application of training in first aid with teachers and school agents, there was an increase in knowledge, skills and abilities to work in the school unit studied.


Objetivo: evaluar el efecto de la formación en primeros auxilios en el conocimiento de docentes y agentes de una unidad escolar. Método: investigación cuantitativa con un diseño cuasi-experimental del tipo pre y post test. La población estuvo compuesta por docentes y agentes escolares de una institución educativa del interior del Estado de São Paulo. La recolección de datos ocurrió entre marzo y abril de 2022, aplicándose dos instrumentos: Caracterización sociodemográfica/laboral y un cuestionario para evaluar conocimientos sobre primeros auxilios. Se utilizó estadística descriptiva, pruebas de Shapiro Wilk y Wilcoxon para analizar los datos. Resultados: Predominó el sexo femenino (66,7%), la edad media fue de 43 años y el 66,7% estaban casados. El 88,9% no participó de cursos de primeros auxilios en formación y el 94,5% dijo haber presenciado situaciones de accidentes en la unidad escolar. Hubo un aumento en el número de respuestas correctas para las preguntas relacionadas con primeros auxilios y una mejora en relación a los conceptos (excelente, bueno, regular y malo), con un aumento en el puntaje del pre-test para el post-test en 3.51 puntos y con la comparación significativa (p<0,001). Conclusión: Los hallazgos muestran que luego de la aplicación de la formación en primeros auxilios con los docentes y agentes escolares, hubo un incremento en los conocimientos y habilidades y destrezas para el trabajo en la unidad escolar estudiada.


Subject(s)
First Aid , Schools , Nursing , Emergency Medical Services
10.
Antibiotics (Basel) ; 10(11)2021 Nov 18.
Article in English | MEDLINE | ID: mdl-34827347

ABSTRACT

The genus Herbaspirillum is widely studied for its ability to associate with grasses and to perform biological nitrogen fixation. However, the bacteria of the Herbaspirillum genus have frequently been isolated from clinical samples. Understanding the genomic characteristics that allow these bacteria to switch environments and become able to colonize human hosts is essential for monitoring emerging pathogens and predicting outbreaks. In this work, we describe the sequencing, assembly, and annotation of the genome of H. frisingense AU14559 isolated from the sputum of patients with cystic fibrosis, and its comparison with the genomes of the uropathogenic strain VT-16-41 and the environmental strains GSF30, BH-1, IAC152, and SG826. The genes responsible for biological nitrogen fixation were absent from all strains except for GSF30. On the other hand, genes encoding virulence and host interaction factors were mostly shared with environmental strains. We also identified a large set of intrinsic antibiotic resistance genes that were shared across all strains. Unlike other strains, in addition to unique genomic islands, AU14559 has a mutation that renders the biosynthesis of rhamnose and its incorporation into the exopolysaccharide unfeasible. These data suggest that H. frisingense has characteristics that provide it with the metabolic diversity needed to infect and colonize human hosts.

11.
Dalton Trans ; 50(36): 12430-12434, 2021 Sep 21.
Article in English | MEDLINE | ID: mdl-34545875

ABSTRACT

We report the unique heterobimetallic dodecanuclear oxamate-based {CoII6CuII6} nanowheel obtained using an environmentally friendly synthetic protocol. The effective Hamiltonian methodology employed herein allows the rationalisation of magnetic isotropic or anisotropic metal clusters, being a significant advance for future studies of exciting properties only observed at low and ultralow temperatures.

12.
Mar Environ Res ; 169: 105394, 2021 Jul.
Article in English | MEDLINE | ID: mdl-34166865

ABSTRACT

Given the ecological and biogeochemical importance of rhodolith beds, it is necessary to investigate how future environmental conditions will affect these organisms. We investigated the impacts of increased nutrient concentrations, acidification, and marine heatwaves on the performance of the rhodolith-forming species Lithothamnion crispatum in a short-term experiment, including the recovery of individuals after stressor removal. Furthermore, we developed an ecological niche model to establish which environmental conditions determine its current distribution along the Brazilian coast and to project responses to future climate scenarios. Although L. crispatum suffered a reduction in photosynthetic performance when exposed to stressors, they returned to pre-experiment values following the return of individuals to control conditions. The model showed that the most important variables in explaining the current distribution of L. crispatum on the Brazilian coast were maximum nitrate and temperature. In future ocean conditions, the model predicted a range expansion of habitat suitability for this species of approximately 58.5% under RCP 8.5. Physiological responses to experimental future environmental conditions corroborated model predictions of the expansion of this species' habitat suitability in the future. This study, therefore, demonstrates the benefits of applying combined approaches to examine potential species responses to climate-change drivers from multiple angles.


Subject(s)
Ecosystem , Rhodophyta , Brazil , Climate Change , Humans , Temperature
13.
Poult Sci ; 100(1): 314-318, 2021 Jan.
Article in English | MEDLINE | ID: mdl-33357695

ABSTRACT

A new poultry litter disinfection methodology against pathogenic Salmonella spp. serovars using gaseous ammonia is proposed in this study. In the laboratory, the poultry litter was disposed into plastic containers and experimentally contaminated with 3 Salmonella spp. serovars separately. Positive and negative control groups were tested. With a system of hoses, 1% gaseous ammonia was injected into the containers in cycles for 48 h. Samples of the poultry litter were collected and submitted to bacteriological analysis. For the second part, we selected a broiler poultry farm with positive litters for Salmonella heidelberg in 2 houses. The littler was treated by gaseous ammonia in a concentration of 2,411 ppm and wrapped with a plastic cover for 48 h during the sanitary break. After the treatment, a new broiler batch was housedand swab samples were collected in the 25-day-old. After the action of the gaseous compound, there was no reisolation of the serovars, and the batches housed on the ammonia-treated litter no longer showed positive results for Salmonella. The total elimination of the pathogenic microorganisms by the new method suggests that the controlled use of ammonia gas in poultry litter may represent a viable disinfection technique.


Subject(s)
Ammonia , Animal Husbandry , Disinfection , Floors and Floorcoverings , Poultry , Salmonella Infections, Animal , Ammonia/pharmacology , Animal Husbandry/methods , Animals , Disinfection/methods , Poultry/microbiology , Salmonella , Salmonella Infections, Animal/prevention & control
14.
Funct Plant Biol ; 48(7): 666-682, 2021 06.
Article in English | MEDLINE | ID: mdl-33256895

ABSTRACT

Previously regarded as an intriguing photosynthetic curiosity, the occurrence of C4 and Crassulacean acid metabolism (CAM) photosynthesis within a single organism has recently emerged as a source of information for future biotechnological use. Among C4/CAM facultative species, Portulaca oleracea L. has been used as a model for biochemical and gene expression analysis of C4/CAM under field and laboratory conditions. In the present work, we focussed on developing molecular tools to facilitate functional genomics studies in this species, from the optimisation of RNA isolation protocols to a method for stable genetic transformation. Eleven variations of RNA extraction procedures were tested and compared for RNA quantity and quality. Also, 7 sample sets comprising total RNA from hormonal and abiotic stress treatments, distinct plant organs, leaf developmental stages, and subspecies were used to select, among 12 reference genes, the most stable reference genes for RT-qPCR analysis of each experimental condition. Furthermore, different explant sources, Agrobacterium tumefaciens strains, and regeneration and antibiotic selection media were tested in various combinations to optimise a protocol for stable genetic transformation of P. oleracea. Altogether, we provide essential tools for functional gene analysis in the context of C4/CAM photosynthesis, including an efficient RNA isolation method, preferred reference genes for RT-qPCR normalisation for a range of experimental conditions, and a protocol to produce P. oleracea stable transformants using A. tumefaciens.


Subject(s)
Portulaca , Carbon Dioxide , Crassulacean Acid Metabolism , Genomics , Photosynthesis/genetics , Portulaca/genetics
15.
Inorg Chem ; 59(18): 12983-12987, 2020 Sep 21.
Article in English | MEDLINE | ID: mdl-32897061

ABSTRACT

Two air-stable, isostructural, mononuclear six-coordinate manganese(II) and cobalt(II) oxamate complexes, [M(4-HOpa)2(H2O)2] [4-HOpa = N-4-hydroxyphenyloxamate; M= Mn2+ (1) or Co2+ (2)], exhibit field-induced slow magnetic relaxation. A bottleneck process is observed throughout the temperature range of 2-20 K for 1, while for 2, it dominates only at low temperatures (2-4 K). Additionally, the Raman process [n = 6.9(2)] is responsible for an increase in the relaxation time at higher temperatures to 2.

16.
Dalton Trans ; 49(45): 16106-16124, 2020 Nov 25.
Article in English | MEDLINE | ID: mdl-32749440

ABSTRACT

Implementing additional optical (luminescent) properties into the well-known class of single-molecule magnets (SMMs) is considered as a promising route toward obtaining the next generation of optomagnetic materials for quantum information storage and computing. Herein, we report a joint optical and magneto-structural study for the two novel series of lanthanide(iii) complexes of general formula Bu4N[LnIII(HL)4(dmso)]·nH2O where H2L = N-(4-Xphenyl)oxamic acid with X = Cl and n = 2 [Ln = Eu (1_Cl), Gd (2_Cl), Dy (3_Cl), and Tb (4_Cl)] and X = F and n = 3 [Ln = Eu (1_F), Gd (2_F), Dy (3_F), and Tb (4_F)]. All these compounds are mononuclear species with each lanthanide(iii) cation in a low-symmetry nine-coordinate environment (LnO9) which is constituted by four didentate monoprotonated oxamate groups and one dmso molecule. Magnetic measurements show the occurrence of field-induced SMM behavior for the Gd3+ (2_Cl and 2_F), Dy3+ (3_Cl and 3_F), and Tb3+ complexes (4_Cl and 4_F). Solid-state photophysical measurements for the Eu3+ (1_Cl and 1_F) and Tb3+ complexes (4_Cl and 4_F) reveal that both monoprotonated chloro- and fluoro-substituted phenyl(oxamate) ligands are able to sensitize the lanthanide(iii)-based luminescence in the visible region, through an energy transfer process ("antenna effect"), as supported by theoretical calculations for Eu3+ compounds. In particular, 1_Cl and 1_F present a quantum efficiency of approximately 50%, being potentially suitable as efficient light conversion molecular devices (LCMDs).

17.
NAR Genom Bioinform ; 2(3): lqaa055, 2020 Sep.
Article in English | MEDLINE | ID: mdl-33575606

ABSTRACT

Bacterial resistance to antibiotics is a global public health problem. Its association with bloodstream infections is even more severe and may easily evolve to sepsis. To improve our response to these bacteria, it is essential to gather thorough knowledge on the main pathogens along with the main mechanisms of resistance they carry. In this paper, we performed a large meta-analysis of 3872 bacterial genomes isolated from blood samples, from which we identified 71 745 antibiotic resistance genes (ARGs). Taxonomic analysis showed that Proteobacteria and Firmicutes phyla, and the species Klebsiella pneumoniae and Staphylococcus aureus were the most represented. Comparison of ARGs with the Resfams database showed that the main mechanism of antibiotic resistance is mediated by efflux pumps. Clustering analysis between resistome of blood and soil-isolated bacteria showed that there is low identity between transport and efflux proteins between bacteria from these environments. Furthermore, a correlation analysis among all features showed that K. pneumoniae and S. aureus formed two well-defined clusters related to the resistance mechanisms, proteins and antibiotics. A retrospective analysis has shown that the average number of ARGs per genome has gradually increased. The results demonstrate the importance of comprehensive studies to understand the antibiotic resistance phenomenon.

18.
BMC Genomics ; 20(1): 630, 2019 Aug 02.
Article in English | MEDLINE | ID: mdl-31375067

ABSTRACT

BACKGROUND: Herbaspirillum seropedicae is an environmental ß-proteobacterium that is capable of promoting the growth of economically relevant plants through biological nitrogen fixation and phytohormone production. However, strains of H. seropedicae have been isolated from immunocompromised patients and associated with human infections and deaths. In this work, we sequenced the genomes of two clinical strains of H. seropedicae, AU14040 and AU13965, and compared them with the genomes of strains described as having an environmental origin. RESULTS: Both genomes were closed, indicating a single circular chromosome; however, strain AU13965 also carried a plasmid of 42,977 bp, the first described in the genus Herbaspirillum. Genome comparison revealed that the clinical strains lost the gene sets related to biological nitrogen fixation (nif) and the type 3 secretion system (T3SS), which has been described to be essential for interactions with plants. Comparison of the pan-genomes of clinical and environmental strains revealed different sets of accessorial genes. However, antimicrobial resistance genes were found in the same proportion in all analyzed genomes. The clinical strains also acquired new genes and genomic islands that may be related to host interactions. Among the acquired islands was a cluster of genes related to lipopolysaccharide (LPS) biosynthesis. Although highly conserved in environmental strains, the LPS biosynthesis genes in the two clinical strains presented unique and non-orthologous genes within the genus Herbaspirillum. Furthermore, the AU14040 strain cluster contained the neuABC genes, which are responsible for sialic acid (Neu5Ac) biosynthesis, indicating that this bacterium could add it to its lipopolysaccharide. The Neu5Ac-linked LPS could increase the bacterial resilience in the host aiding in the evasion of the immune system. CONCLUSIONS: Our findings suggest that the lifestyle transition from environment to opportunist led to the loss and acquisition of specific genes allowing adaptations to colonize and survive in new hosts. It is possible that these substitutions may be the starting point for interactions with new hosts.


Subject(s)
Adaptation, Physiological/genetics , Environment , Genomics , Herbaspirillum/genetics , Herbaspirillum/physiology , Host-Pathogen Interactions/genetics , Evolution, Molecular , Genome, Bacterial/genetics , Genomic Islands/genetics , Herbaspirillum/metabolism , Humans , Lipopolysaccharides/biosynthesis , Phylogeny , Siderophores/biosynthesis , Species Specificity
19.
J Anim Physiol Anim Nutr (Berl) ; 103(3): 756-765, 2019 May.
Article in English | MEDLINE | ID: mdl-30761617

ABSTRACT

This study evaluated the antimicrobial effect of essential oils (EO) and organic acids (OA) against Salmonella Enteritidis in chicken feed and during an in vitro model that mimics the chicken digestive process. The minimal inhibitory concentration (MIC) of allyl isothiocyanate (AITC), carvacrol (CV), propionic acid (PROP) and caproic acid (CAP) were individually determined. Then, based on the MICs of each compound, combinations of EOs and/or OAs were tested to evaluate their synergic antimicrobial effect. The synergic effect of AITC and CAP was the most efficient against the bacterial strain tested. Commercial feed was inoculated with a 5-strain cocktail of S. Enteritidis and treated with different doses of AITC + CAP to evaluate their effect on the growth/survival of the pathogen. In addition, the simulated digestion model was used to access the antimicrobial effect of AITC + CAP added to the feed towards S. Enteritidis and Lactobacillus plantarum. Synergistic effect was found between AITC (0.065 mM) and CAP (17.5 mM) against S. Enteritidis in chicken feed, where S. Enteritidis was reduced to undetectable levels (<1.00 log CFU/g). AITC (1.95 mM) + CAP (45 mM) also decreased (p < 0.05) the population of S. Enteritidis in the simulated digestion, while the growth of L. plantarum was not affected. Therefore, the addition of AITC + CAP in feed might be a potential natural antimicrobial able to prevent economic losses caused for Salmonella in chicken.


Subject(s)
Animal Feed/microbiology , Anti-Infective Agents/pharmacology , Biological Products/pharmacology , Chickens , Digestion/physiology , Salmonella enteritidis/drug effects , Animals , Food Microbiology , Microbial Sensitivity Tests
20.
IEEE J Biomed Health Inform ; 23(6): 2220-2229, 2019 11.
Article in English | MEDLINE | ID: mdl-30452381

ABSTRACT

Content-based retrieval still remains one of the main problems with respect to controversies and challenges in digital healthcare over big data. To properly address this problem, there is a need for efficient computational techniques, especially in scenarios involving queries across multiple data repositories. In such scenarios, the common computational approach searches the repositories separately and combines the results into one final response, which slows down the process altogether. In order to improve the performance of queries in that kind of scenario, we present the Domain Index, a new category of index structures intended to efficiently query a data domain across multiple repositories, regardless of the repository to which the data belong. To evaluate our method, we carried out experiments involving content-based queries, namely range and k nearest neighbor (kNN) queries, 1) over real-world data from a public data set of mammograms, as well as 2) over synthetic data to perform scalability evaluations. The results show that images from any repository are seamlessly retrieved, sustaining performance gains of up to 53% in range queries and up to 81% in kNN queries. Regarding scalability, our proposal scaled well as we increased 1) the cardinality of data (up to 59% of gain) and 2) the number of queried repositories (up to 71% of gain). Hence, our method enables significant performance improvements, and should be of most importance for medical data repository maintainers and for physicians' IT support.


Subject(s)
Databases, Factual , Diagnostic Imaging , Information Storage and Retrieval/methods , Medical Informatics/methods , Algorithms , Big Data , Humans , Mammography
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