Klebsiella pneumoniae is an important opportunistic pathogen that commonly causes nosocomial infections and contributes to substantial morbidity and mortality. We sought to investigate the antibiotic resistance profile, pathogenic potential and the clonal relationships between K. pneumoniae (n = 25) isolated from patients and sources at a tertiary care hospital’s intensive care units (ICUs) in the northern region of Brazil. Most of K. pneumoniae isolates (n = 21, 84%) were classified as multidrug resistant (MDR) with high-level resistance to β-lactams, aminoglycosides, quinolones, tigecycline, and colistin. All the 25 isolates presented extended-spectrum beta-lactamase-producing (ESBL), including carbapenemase producers, and carried the blaKPC (100%), blaTEM (100%), blaSHV variants (n = 24, 96%), blaOXA-1 group (n = 21, 84%) and blaCTX-M-1 group (n = 18, 72%) genes. The K2 serotype was found in 4% (n = 1) of the isolates, and the K1 was not detected. The virulence-associated genes found among the 25 isolates were mrkD (n = 24, 96%), fimH-1 (n = 22, 88%), entB (100%), iutA (n = 10, 40%), ybtS (n = 15, 60%). The genes related with efflux pumps and outer membrane porins found were AcrAB (100%), tolC (n = 24, 96%), mdtK (n = 22, 88%), OmpK35 (n = 15, 60%), and OmpK36 (n = 7, 28%). ERIC-PCR was employed to determine the clonal relationship between the different isolated strains. The obtained ERIC-PCR patterns revealed that the similarity between isolates was above 70%. To determine the sequence types (STs) a multilocus sequence typing (MLST) assay was used. The results indicated the presence of high-risk international clones among the isolates. In our study, the wide variety of MDR K. pneumoniae harboring β-lactams and virulence genes strongly suggest a necessity for the implementation of effective strategies to prevent and control the spread of antibiotic resistant infections.

Serratia marcescens has emerged as an important opportunistic pathogen responsible for nosocomial and severe infections. Here, we determined phenotypic and molecular characteristics of 54 S. marcescens isolates obtained from patient samples from intensive-care-unit (ICU) and neonatal intensive-care-unit (NIUC) of a Brazilian tertiary hospital. All isolates were resistant to beta-lactam group antibiotics, and 92.6% (50/54) were not susceptible to tigecycline. Furthermore, 96.3% showed intrinsic resistance to polymyxin E (colistin), a last-resort antibiotic for the treatment of infections caused by MDR (multidrug-resistant) Gram-negative bacteria. In contrast, high susceptibility to other antibiotics such as fluoroquinolones (81.5%), and to aminoglycosides (as gentamicin 81.5%, and amikacin 85.2%) was found. Of all isolates, 24.1% were classified as MDR. The presence of resistance and virulence genes were examined by PCR and sequencing. All isolates carried KPC-carbapenemase (bla KPC) and extended spectrum beta-lactamase bla TEM genes, 14.8% carried bla OXA−1 , and 16.7% carried bla CTX−M−1group genes, suggesting that bacterial resistance to β-lactam antibiotics found may be associated with these genes. The genes SdeB/HasF and SdeY/HasF that are associated with efflux pump mediated drug extrusion to fluoroquinolones and tigecycline, respectively, were found in 88.9%. The aac(6)-Ib-cr variant gene that can simultaneously induce resistance to aminoglycoside and fluoroquinolone was present in 24.1% of the isolates. Notably, the virulence genes to (i) pore-forming toxin (ShlA); (ii) phospholipase with hemolytic and cytolytic activities (PhlA); (iii) flagellar transcriptional regulator (FlhD); and (iv) positive regulator of prodigiosin and serratamolide production (PigP) were present in 98.2%. The genetic relationship among the isolates determined by ERIC-PCR demonstrated that the vast majority of isolates were grouped in a single cluster with 86.4% genetic similarity. In addition, many isolates showed 100% genetic similarity to each other, suggesting that the S. marcescens that circulate in this ICU are closely related. Our results suggest that the antimicrobial resistance to many drugs

The objective of this study was to evaluate, in greenhouse, the response of the lettuce cultivar 'Vera', with respect to the marketable shoot dry matter production and macronutrient accumulation, as a function of the application of different doses of nitrogen (N) and a potassium silicate-based leaf fertilizer. The lettuce was cultivated from August 10, 2012 (sowing) to October 16, 2012 (harvest). The experimental design was completely randomized with three replicates, referring to nine treatments, resulting from the combination between top-dressing doses of N (9, 54, 90, 126 and 171 kg ha-1) and Si/K2O (1.15, 6.90, 11.50, 16.10 and 21.85 kg ha-1), using the Plan Puebla III experimental matrix, and a control treatment without fertigation. Drip fertigation was used for the application of the doses. The highest doses of N and Si/K2O resulted in the highest marketable shoot dry matter production and highest leaf accumulation of magnesium, calcium, potassium and phosphorus.

Produção e qualidade comercial de alface fertirrigada com nitrogênio e potássio em ambiente protegidoA adubação orgânica pode fornecer grande parte dos nutrientes necessários à cultura da alface. No entanto, a taxa de mineralização de nutrientes pode ser limitante à absorção, sendo que outras formas de adubação complementares com fertilizantes solúveis podem ser utilizadas, como a fertirrigação. O objetivo deste trabalho foi avaliar o efeito da fertirrigação por gotejamento, com nitrogênio e potássio, aliada à adubação de plantio, no crescimento da alface Vera, cultivada em ambiente protegido. O experimento foi realizado entre agosto e outubro de 2012 (inverno e primavera; 67 dias). O delineamento experimental foi inteiramente aleatorizado, com três repetições. Os tratamentos foram formados pela matriz Plan Puebla III, isto é, da combinação entre cinco doses de nitrogênio (N) (9; 54; 90; 126 e 171 kg ha -1 ) e cinco doses de potássio (1,15; 6,90; 11,50; 16,10 e 21,85 kg ha -1 ), além da testemunha, que não recebeu fertirrigação. Concluiuse que a fertirrigação pode ser utilizada para o crescimento da cultura mesmo com adubação orgânica de plantio. As maiores doses de N e de K 2 O resultaram no maior número de folhas comerciais por planta. Os aumentos das doses de N e de K 2 O promoveram incrementos da matéria fresca não comercial da parte aérea, sem prejuízo à qualidade comercial. Palavras Production and commercial quality of lettuce fertirrigated with nitrogen and potassium in greenhouseOrganic fertilization can provide most of the nutrients needed to grow lettuce crop. However, the rate of nutrient mineralization may be limiting to absorption, once complementary forms of fertilization with soluble fertilizers can be used, such as fertirrigation. The objective of this work was to evaluate the effect of the drip fertirrigation with nitrogen and potassium with organic fertilization in the production and commercial quality of the Vera lettuce cultivated in greenhouse. The cultivation period used for the experiment was between August and October 2012 (winter and spring; 67 days). The experimental design was completely randomized with three replications, in which ten treatments were evaluated, with nine of them formed by the Plan Puebla III matrix, that is, from the combination among five N (9, 54, 90, 126, and 171 kg ha -1 ) and five K doses (1. 15, 6.90, 11.50, 16.10, and 21.85 kg ha -1 ), applied in topdressing, and one of them as control, which did not receive fertirrigation. The best answer to the shoot commercial fresh mass took place with the maximum dose of Si and K 2 O and in the zero dose of N. The commercial leaf number per plant showed their higher values in the maximum doses of N and Si and K 2 O. The shoot noncommercial fresh mass increment, both with the increase in N doses and with the increase in Si and K 2 O doses, did not harm the commercial quality.

Background Swine production expanded in the last decades. Efforts have been made to improve meat production and to understand its relationship to pig gut microbiota. Copper (Cu) is a usual supplement to growth performance in animal production. Here, two performance studies were conducted to investigate the effects of three different sources of Cu on the microbiota of piglets. A total of 256 weaned piglets were randomly allocated into 4 treatments (10 replicates per treatment of 4 piglets per pen in Trial 1 and 8 replicates of 3 piglets per pen in Trial 2). Treatments included a control group (fed 10 mg/kg of Cu from CuSO4), a group fed at 160 mg/kg of Copper (II) sulfate (CuSO4) or tri-basic copper chloride (TBCC), and a group fed with Cu methionine hydroxy analogue chelated (Cu-MHAC) at 150, 80, and 50 mg/kg in Phases 1 (24–35 d), 2 (36–49 d), and 3 (50–70 d), respectively. At 70 d, the cecum luminal contents from one pig per pen were collected and polled for 16 S rRNA sequencing (V3/V4 regions). Parameters were analyzed in a completely randomized block design, in which each experiment was considered as a block. Results A total of 1337 Operational Taxonomic Units (OTUs) were identified. Dominance and Simpson ecological metrics were statistically different between control and treated groups (P < 0.10) showing that different Cu sources altered the gut microbiota composition with the proliferation of some bacteria that improve gut health. A high abundance of Prevotella was observed in all treatments while other genera were enriched and differentially modulated, according to the Cu source and dosage. The supplementation with Cu-MHAC can modify a group of bacteria involved in feed efficiency (FE) and short chain fatty acids (SCFA) production (Clostridium XIVa, Desulfovibrio, and Megasphera). These bacteria are also important players in the activation of ghrelin and growth hormones that were previously reported to correlate with Cu-MHAC supplementation. Conclusions These results indicated that some genera seem to be directly affected by the Cu source offered to the animals. TBCC and Cu-MHAC (even in low doses) can promote healthy modifications in the gut bacterial composition, being a promising source of supplementation for piglets.