9 research outputs found
Energy partition and methane production in sheep fed with Andropogon Gayanus hays in three different ages
Foi realizado estudo para descrever a partição da energia e produção de metano por ovinos alimentados com fenos do capim Andropogon gayanus colhidos aos 56, 84 e 112 dias de crescimento. Utilizou-se a metodologia da calorimetria indireta para mensuração das perdas de energia e para a determinação da energia digestível (ED), metabolizável (EM) e líquida (EL). O delineamento experimental foi inteiramente casualizado, sendo constituído de três tratamentos e seis repetições. As médias foram comparadas pelo teste Studant-Newman- Keuls (SNK) ao nível de 5% de significância. O feno, cujo material foi colhido aos 56 dias, resultou em maior (P<0,05) consumo de energia digestível (CED) em relação aos materiais fenados com 84 e 112 dias de rebrote.
As perdas diárias de energia através da urina, do metano e do incremento calórico não apresentaram diferença (P>0,05) entre os tratamentos. O feno contendo material colhido aos 56 dias apresentou valor de digestibilidade aparente da energia bruta (DAEB) superior (P0,05) entre si.
O feno colhido as 56 dias apresentou maior valor de energia digestível e energia metabolizavél em relação aos demais fenos que não diferiram entre si (P>0,05). A produção de metano não variou (P>0,05) entre os tratamentos estudados.A study was conducted to describe the energy partition and methane production by sheep fed grass hay of Andropogon gayanus harvested at 56, 84 and 112 days of growth. We used the methodology of indirect calorimetry to measure energy losses and to determine the digestible energy (DE), metabolizable (ME) and liquid (EL). The experimental design was completely randomized, consisting of three treatments and six replications.
Means were compared by Studant -Newman -Keuls (SNK) test at 5 % significance level. Hays was collected at 56 days, resulted in higher (P < 0.05) digestible energy intake (DEI) in relation to hays 84 and 112 days of regrowth.
The daily energy losses through urine, methane and heat increment did not differ (P> 0.05) between treatments.
Hay containing material collected at 56 days showed apparent digestibility of the gross energy value higher ( P < 0.5) to the other treatments did not differ ( P> 0.05 ) between them. Hay harvested the 56 days had higher digestible energy and metabolizable energy value compared to other hays that did not differ (P> 0.05). The methane production did not change (P> 0.05) between the treatments.Facultad de Ciencias Agrarias y Forestale
Energy partition and methane production in sheep fed with Andropogon Gayanus hays in three different ages
Foi realizado estudo para descrever a partição da energia e produção de metano por ovinos alimentados com fenos do capim Andropogon gayanus colhidos aos 56, 84 e 112 dias de crescimento. Utilizou-se a metodologia da calorimetria indireta para mensuração das perdas de energia e para a determinação da energia digestível (ED), metabolizável (EM) e líquida (EL). O delineamento experimental foi inteiramente casualizado, sendo constituído de três tratamentos e seis repetições. As médias foram comparadas pelo teste Studant-Newman- Keuls (SNK) ao nível de 5% de significância. O feno, cujo material foi colhido aos 56 dias, resultou em maior (P<0,05) consumo de energia digestível (CED) em relação aos materiais fenados com 84 e 112 dias de rebrote.
As perdas diárias de energia através da urina, do metano e do incremento calórico não apresentaram diferença (P>0,05) entre os tratamentos. O feno contendo material colhido aos 56 dias apresentou valor de digestibilidade aparente da energia bruta (DAEB) superior (P0,05) entre si.
O feno colhido as 56 dias apresentou maior valor de energia digestível e energia metabolizavél em relação aos demais fenos que não diferiram entre si (P>0,05). A produção de metano não variou (P>0,05) entre os tratamentos estudados.A study was conducted to describe the energy partition and methane production by sheep fed grass hay of Andropogon gayanus harvested at 56, 84 and 112 days of growth. We used the methodology of indirect calorimetry to measure energy losses and to determine the digestible energy (DE), metabolizable (ME) and liquid (EL). The experimental design was completely randomized, consisting of three treatments and six replications.
Means were compared by Studant -Newman -Keuls (SNK) test at 5 % significance level. Hays was collected at 56 days, resulted in higher (P < 0.05) digestible energy intake (DEI) in relation to hays 84 and 112 days of regrowth.
The daily energy losses through urine, methane and heat increment did not differ (P> 0.05) between treatments.
Hay containing material collected at 56 days showed apparent digestibility of the gross energy value higher ( P < 0.5) to the other treatments did not differ ( P> 0.05 ) between them. Hay harvested the 56 days had higher digestible energy and metabolizable energy value compared to other hays that did not differ (P> 0.05). The methane production did not change (P> 0.05) between the treatments.Facultad de Ciencias Agrarias y Forestale
An emerging clone, KPC-2-producing Klebsiella pneumoniae ST16, associated with high mortality rates in a CC258 endemic setting
Background
Carbapenemase-producing K. pneumoniae have become a global priority, not least in low-middle income countries. Here, we report the emergence and clinical impact of a novel KPC-K. pneumoniae ST16 clone in a Clonal Complex (CC)258 endemic setting.
Methods
In a teaching Brazilian hospital, a retrospective cohort of adult KPC-KP bloodstream infections (BSI) cases (January 2014 to December 2016) was established to study the molecular epidemiology and its impact on outcome (30-day all-cause mortality). KPC-KP isolates were MLST-typed. Survival analysis between ST/CC groups and risk factors for fatal outcome (logistic regression) were evaluated. Representative isolates underwent whole genome sequencing (WGS), and had their virulence tested in a Galleria larvae model.
Results
One hundred sixty-five unique KPC-KP BSI cases were identified. CC258 was predominant (66%), followed by ST16 (12%). The overall 30-day mortality rate was 60%; in contrast, 95% of ST16 cases were fatal. Patient’s severity scores were high and baseline clinical variables were not statistically different across ST’s. In multivariate analysis, ST16 (OR 21.4; CI95% 2.3-202.8; p=0,008) and septic shock (OR 11.9; CI95% 4.2-34.1; p<0,001) were independent risk factors for fatal outcome. ST16 clone carried up to 14 resistance genes, including blaKPC-2 in an IncFIBpQIL plasmid, KL51 capsule and Yersiniabactin virulence determinants. ST16 clone was highly pathogenic in the larvae model.
Conclusions
Mortality rates were high in this KPC-KP BSI cohort, where CC258 is endemic. An emerging ST16 clone was associated with high mortality. Our results suggest that even in endemic settings, highly virulent clones can rapidly emerge demanding constant monitoring
Drug resistance, AmpC-β-lactamase and extended-spectrum β-lactamase-producing Enterobacteriaceae isolated from fish and shrimp
Comparison of the Virulence Potential of Acinetobacter Strains from Clinical and Environmental Sources
Several Acinetobacter strains have utility for biotechnology applications, yet some are opportunistic pathogens. We compared strains of seven Acinetobacter species (baumannii, Ab; calcoaceticus, Ac; guillouiae, Ag; haemolyticus, Ah; lwoffii, Al; junii, Aj; and venetianus, Av-RAG-1) for their potential virulence attributes, including proliferation in mammalian cell conditions, haemolytic/cytolytic activity, ability to elicit inflammatory signals, and antibiotic susceptibility. Only Ah grew at 102 and 104 bacteria/well in mammalian cell culture medium at 37°C. However, co-culture with colonic epithelial cells (HT29) improved growth of all bacterial strains, except Av-RAG-1. Cytotoxicity of Ab and Ah toward HT29 was at least double that of other test bacteria. These effects included bacterial adherence, loss of metabolism, substrate detachment, and cytolysis. Only Ab and Ah exhibited resistance to killing by macrophage-like J774A.1 cells. Haemolytic activity of Ah and Av-RAG-1 was strong, but undetectable for other strains. When killed with an antibiotic, Ab, Ah, Aj and Av-RAG-1 induced 3 to 9-fold elevated HT29 interleukin (IL)-8 levels. However, none of the strains altered levels of J774A.1 pro-inflammatory cytokines (IL-1β, IL-6 and tumor necrosis factor-α). Antibiotic susceptibility profiling showed that Ab, Ag and Aj were viable at low concentrations of some antibiotics. All strains were positive for virulence factor genes ompA and epsA, and negative for mutations in gyrA and parC genes that convey fluoroquinolone resistance. The data demonstrate that Av-RAG-1, Ag and Al lack some potentially harmful characteristics compared to other Acinetobacter strains tested, but the biotechnology candidate Av-RAG-1 should be scrutinized further prior to widespread use
Diversity of metallo-β-lactamase-encoding genes found in distinct species of Acinetobacter isolated from the Brazilian Amazon Region
Evandro Chagas Institute, CAPES grants to APS and CSN (DS-CAPES), CNPq (grant to ACG - Process nº 305535/2014-5).Ministério da Saúde. Secretaria de Vigilância em Saúde. Instituto Evandro Chagas. Ananindeua, PA, Brasil.Universidade Federal de São Paulo. Instituto de Ciências Ambientais, Químicas e Farmacêuticas. Departamento de Ciências Biológicas. Setor de Biologia Molecular, Microbiologia e Imunologia. Diadema, SP, Brasil.Universidade Federal de São Paulo. Departamento de Medicina. Escola Paulista de Medicina. Laboratório Alerta. Disciplina de Infectologia. São Paulo, SP, Brasil.Universidade Federal de São Paulo. Departamento de Medicina. Escola Paulista de Medicina. Laboratório Alerta. Disciplina de Infectologia. São Paulo, SP, Brasil.Ministério da Saúde. Secretaria de Vigilância em Saúde. Instituto Evandro Chagas. Centro de Inovação Tecnológica. Ananindeua, PA, Brasil.Ministério da Saúde. Secretaria de Vigilância em Saúde. Instituto Evandro Chagas. Centro de Inovação Tecnológica. Ananindeua, PA, Brasil.Ministério da Saúde. Secretaria de Vigilância em Saúde. Instituto Evandro Chagas. Centro de Inovação Tecnológica. Ananindeua, PA, Brasil.Ministério da Saúde. Secretaria de Vigilância em Saúde. Instituto Evandro Chagas. Ananindeua, PA, Brasil.Ministério da Saúde. Secretaria de Vigilância em Saúde. Instituto Evandro Chagas. Ananindeua, PA, Brasil.Universidade Federal de São Paulo. Departamento de Medicina. Escola Paulista de Medicina. Laboratório Alerta. Disciplina de Infectologia. São Paulo, SP, Brasil.Hospital Fundação Santa Casa de Misericórdia do Pará. Belém, PA, Brasil.BACKGROUND: The multidrug resistance (MDR) phenotype is frequently observed in Acinetobacter baumannii, the most clinically relevant pathogenic species of its genus; recently, other species belonging to the A. calcoaceticus-A. baumannii complex have emerged as important MDR nosocomial pathogens.
OBJECTIVES: The present study aimed to verify the occurrence of metallo-β-lactamase genes among distinct Acinetobacter species in a hospital located in the Brazilian Amazon Region.
METHODS: Antimicrobial susceptibility profiles were determined by broth microdilution. The genetic relationships among these isolates were assessed by pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST). Pyrosequencing reads of plasmids carrying the bla NDM-1 gene were generated using the Ion Torrent™ platform sequencing.
FINDINGS: A total of six isolates carried bla NDM-1: A. baumannii (n = 2), A. nosocomialis (n = 3), and A. pittii (n = 1); three carried bla IMP-1: A. baumannii, A. nosocomialis, and A. bereziniae. Resistance to colistin was observed for an NDM-1-producing A. nosocomialis isolate. Diverse PFGE patterns and sequence types were found among A. nosocomialis and A. baumannii isolates. The bla NDM-1 sequence was inserted in a Tn125 transposon, while the bla IMP-1 was found as a gene cassette of the class 1 integron In86.
MAIN CONCLUSIONS: To the best of our knowledge, this is the first report describing the dissemination of bla NDM-1 among distinct Acinetobacter species recovered from the same hospital in South America
A new mutation in mgrb mediating polymyxin resistance in Klebsiella variicola
Polymyxin resistance is a public health concern – present in humans, animals and the environment – caused by chromosomal-encoding or plasmid-encoding mechanisms. Chromosomal alterations in MgrB are frequently detected in Klebsiella spp., but not yet reported and characterised in Klebsiella variicola (K. variicola). This study performed microbiological and genomic characterisation of three polymyxin-resistant K. variicola isolates (M14, M15 and M50) recovered from the microbiota of migratory birds in Brazil.
The isolates were submitted to SpeI-PFGE, broth microdilution and whole genome sequencing using Illumina MiSeq for analysis of genetic relatedness, sequence typing and detection of antimicrobial-resistance genes. K. variicola isolates belonged to two clones, and susceptibility tests showed resistance only for polymyxins. Sequences of chromosomal two-component systems (PmrAB, PhoPQ, RstAB, CrrAB) and MgrB were evaluated by blastN and blastP against a polymyxin-susceptible K. variicola (A58243), and mutations with biological effect were checked by the PROVEAN tool. K. variicola isolates belonged to two clones, and susceptibility tests showed resistance for polymyxins. In M14 and M15, phoQ deleterious mutations (D90N, I122S and G385S) were identified, while an mgrB variant containing a single deletion (C deletion on position 93) leading to the production of a non-functional protein was detected in M50. mgrB complementation studies showed restoration of polymyxin susceptibility (64 to ≤ 0.25 mg/L) as a wild-type mgrB was inserted into the mgrB-deficient M50.
This study confirmed the role of a non-functional mgrB variant in conferring polymyxin resistance, stressing the role of this regulator in K. variicola and drawing attention to novel polymyxin resistance mechanisms emerging in wildlife