Increased vitamin supplement to sows, piglets and finishers and the effect in productivity.

With still limited information on vitamin requirements and considering that many commercial practices adopt dietary vitamin levels above the values suggested by nutritional tables, this study aimed to assess the effect of administering vitamin supplementation to sows in gestation and lactation and to their litters on the reproductive performance and body condition of the sows and on the performance and immune profile of the litters until slaughter. The trial was split into two phases. The first phase used 104 sows, assigned to be randomized to blocks according to parity, submitted until 21 days of lactation to two treatments: control-standard (standard levels of vitamins) and test-elevated (elevated levels of vitamins). Each sow and its respective farrow were considered an experimental unit. The sows underwent evaluations of body condition score, back fat thickness and reproductive performance. In the second phase, 60 barrows and 60 gilts at 21 days of age and mean initial weight of 5.33 ± 1.5 kg until slaughter at 164 days of age. The piglets were assigned to randomized blocks according to the weight and sex of the animals in a 2 × 2 factorial model, with 10 replicates per treatment, where a pen with three animals represented the experimental unit. Following the same treatments of the first phase, the piglets were evaluated for daily weight gain, daily feed intake, feed conversion, mortality rate and humoral immune response. Vitamin supplementation had no positive effects on the reproductive parameters or body composition of sows. However, it positively impacted the performance of the litters in the early nursery stage, but did not lead to superior effects on the immune responses to vaccination against circovirus or mycoplasma.

Tissue-specific profiling reveals modulation of cellular and mitochondrial oxidative stress in normal- and low-birthweight piglets throughout the peri-weaning period.

Weaning is known to induce important nutritional and energetic stress in piglets. Low-birthweight (LBW) piglets, now frequently observed in swine production, are more likely to be affected. The weaning period is also associated with dysfunctional immune responses, uncontrolled inflammation and oxidative stress conditions that are recognized risk factors for infections and diseases. Mounting evidence indicates that mitochondria, the main cellular sources of energy in the form of adenosine 5' triphosphate (ATP) and primary sites of reactive oxygen species production, are related to immunity, inflammation and bacterial pathogenesis. However, no information is currently available regarding the link between mitochondrial energy production and oxidative stress in weaned piglets. The objective of this study was to characterize markers of cellular and mitochondrial energy metabolism and oxidative status in both normal-birthweight (NBW) and LBW piglets throughout the peri-weaning period. To conduct the study, 30 multiparous sows were inseminated and litters were standardized to 12 piglets. All the piglets were weighted at day 1 and 120 piglets were selected and assigned to 1 of 2 experimental groups: NBW (n = 60, mean weight of 1.73 ± 0.01 kg) and LBW piglets weighing less than 1.2 kg (n = 60, 1.01 ± 0.01 kg). Then, 10 piglets from each group were selected at 14, 21 (weaning), 23, 25, 29 and 35 days of age to collect plasma and organ (liver, intestine and kidney) samples. Analysis revealed that ATP concentrations were lower in liver of piglets after weaning than during lactation (P < 0.05) thus suggesting a significant impact of weaning stress on mitochondrial energy production. Oxidative damage to DNA (8-hydroxy-2'-deoxyguanosine, 8-OHdG) and proteins (carbonyls) measured in plasma increased after weaning and this coincides with a rise in enzymatic antioxidant activity of glutathione peroxidase (GPx) and superoxide dismutase (SOD) (P < 0.05). Mitochondrial activities of both GPx and SOD are also significantly higher (P < 0.05) in kidney of piglets after weaning. Additionally, oxidative damage to macromolecules is more important in LBW piglets as measured concentrations of 8-OHdG and protein carbonyls are significantly higher (P < 0.05) in plasma and liver samples, respectively, than for NBW piglets. These results provide novel information about the nature, intensity and duration of weaning stress by revealing that weaning induces mitochondrial dysfunction and cellular oxidative stress conditions which last for at least 2 weeks and more severely impact smaller piglets.

The SIGMA rat brain templates and atlases for multimodal MRI data analysis and visualization.

Preclinical imaging studies offer a unique access to the rat brain, allowing investigations that go beyond what is possible in human studies. Unfortunately, these techniques still suffer from a lack of dedicated and standardized neuroimaging tools, namely brain templates and descriptive atlases. Here, we present two rat brain MRI templates and their associated gray matter, white matter and cerebrospinal fluid probability maps, generated from ex vivo [Formula: see text]-weighted images (90 µm isotropic resolution) and in vivo T2-weighted images (150 µm isotropic resolution). In association with these templates, we also provide both anatomical and functional 3D brain atlases, respectively derived from the merging of the Waxholm and Tohoku atlases, and analysis of resting-state functional MRI data. Finally, we propose a complete set of preclinical MRI reference resources, compatible with common neuroimaging software, for the investigation of rat brain structures and functions.

Dynamics of clonal and plasmid backgrounds of Enterobacteriaceae producing acquired AmpC in Portuguese clinical settings over time.

OBJECTIVES: The objective of this work was to provide detailed molecular data on clinically acquired AmpC (qAmpC)-producing Enterobacteriaceae from two different periods (2002-2008 and 2010-2013) in order to clarify the contribution of clonal and plasmid genetic platforms for the current epidemiological scenario concerning extended-spectrum beta-lactams resistance. METHODS: We analysed 1246 Enterobacteriaceae non-susceptible to third-generation cephalosporins from two hospitals and one community laboratory between 2010 and 2013. Bacterial identification, antibiotic susceptibility, identification of qAmpC and plasmid-mediated quinolone resistance genes, clonal (pulsed-field gel electrophoresis (PFGE), Multilocus sequence typing (MLST)) and plasmid (S1-/I-CeuI-PFGE, replicon typing, hybridization) analysis were performed by standard methods. Whole-genome sequencing (WGS) was performed in two ST11-Klebsiella pneumoniae isolates harbouring DHA-1. RESULTS: The occurrence of qAmpC was lower (2.6%) than that observed in a previous survey (7.4%), and varied slightly over time. Isolates produced DHA-1 (53%), CMY-2 (44%) or DHA-6 (3%), but significant epidemiological changes were observed in the two surveys. While DHA-1 persisted in different institutions by selection of a worldwide epidemic IncR plasmid in an ST11 harbouring KL105, CMY-2 rates increased over time linked to IncI1 plasmids (instead of IncK or IncA/C2) in multiple Escherichia coli clones. CONCLUSIONS: The higher frequency of DHA-1 qAmpC in these species contrasts with the scenario in most European countries. Furthermore, the different genetic backgrounds associated with either extended-spectrum ß-lactamases (ESBLs) or acquired AmpC ß-lactamases (qAmpC) in our country might have contributed to their differential expansion.

Caracterização dos fatores de produção e uso de modelos matemáticos para estimar sua influência sobre o consumo diário de ração e a conversão alimentar de suínos nas fases de crescimento e terminação / Characterization of production factors and use of mathematical models to estimate their influence on daily feed intake and feed conversion ratio of grow-finishing pigs

O objetivo deste estudo foi identificar e quantificar os fatores de produção presentes em granjas de crescimento e terminação (CT) de suínos, em um sistema cooperativo do estado do Paraná, Brasil, e determinar a influência desses fatores no consumo diário de ração (CDR) e na conversão alimentar (CA). Foram avaliados, entre os anos de 2010 e 2013, os históricos produtivos de 538 lotes de engorda, alojados em 175 granjas comerciais, totalizando aproximadamente 404.000 animais. Foram considerados 40 fatores de produção, relacionados ao manejo, à sanidade, às instalações e aos equipamentos, à nutrição, à genética e ao ambiente. Em baias com menos de 20 suínos, o CDR diminuiu (P<0,05) e a CA melhorou (P<0,01). Nas baias com comedouros basculantes (lineares), o CDR reduziu (P<0,01) e a CA melhorou (P=0,001). Em baias com lâmina d'água, o CDR aumentou (P<0,01) e a CA piorou (P<0,01). Lotes formados apenas por fêmeas apresentaram menor CDR (P<0,001) e melhor CA (P<0,001), quando comparados aos lotes mistos. As variáveis selecionadas para os modelos finais explicaram cerca de 25% e 46% da variância total para CDR e para a CA, respectivamente. Os modelos constituem um instrumento de auxílio efetivo para tomadas de decisões técnicas dentro do setor suinícola.(AU)

The aim of this study was to identify and quantify the production factors present in growing and finishing (GF) pig farms partners of a cooperative in Paraná State, Brazil, and to determine the influence of these factors on daily feed intake (DFI) and the feed conversion ratio (FCR). From 2010 to 2013, the historical production of 538 batches of fattening pigs in 175 commercial farms were analyzed, in an amount approximately 404,000 animals. A total of 40 production factors regarding the management, sanity, plant and equipment, nutrition, genetics and environment were taken into consideration. Pens with less than 20 pigs resulted in a reduction in DFI (P<0.05) and an improved FCR (P<0.01). In pens that used linear dump feeders, the DFI was less (P<0.01) and the FCR was better (P=0.001). Pens with shallow pools had higher DFI (P<0.01) and worse FCR (P<0.01). Batches of females had lower DFI (P<0.001) and better FCR (P<0.001) compared to mixed-sex batches. The factors used for the final models explained the 25% and 46% of the total variance for the DFI and FCR, respectively. The models consist in effective aid instruments for technical decision making in the swine industry.(AU)

Lipocalin-2 regulates adult neurogenesis and contextual discriminative behaviours.

In the adult mammalian brain, newborn granule cells are continuously integrated into hippocampal circuits, and the fine-tuning of this process is important for hippocampal function. Thus, the identification of factors that control adult neural stem cells (NSCs) maintenance, differentiation and integration is essential. Here we show that the deletion of the iron trafficking protein lipocalin-2 (LCN2) induces deficits in NSCs proliferation and commitment, with impact on the hippocampal-dependent contextual fear discriminative task. Mice deficient in LCN2 present an increase in the NSCs population, as a consequence of a G0/G1 cell cycle arrest induced by increased endogenous oxidative stress. Of notice, supplementation with the iron-chelating agent deferoxamine rescues NSCs oxidative stress, promotes cell cycle progression and improves contextual fear conditioning. LCN2 is, therefore, a novel key modulator of neurogenesis that, through iron, controls NSCs cell cycle progression and death, self-renewal, proliferation and differentiation and, ultimately, hippocampal function.

The dynamics of stress: a longitudinal MRI study of rat brain structure and connectome.

Stress is a well-established trigger for a number of neuropsychiatric disorders, as it alters both structure and function of several brain regions and its networks. Herein, we conduct a longitudinal neuroimaging study to assess how a chronic unpredictable stress protocol impacts the structure of the rat brain and its functional connectome in both high and low responders to stress. Our results reveal the changes that stress triggers in the brain, with structural atrophy affecting key regions such as the prelimbic, cingulate, insular and retrosplenial, somatosensory, motor, auditory and perirhinal/entorhinal cortices, the hippocampus, the dorsomedial striatum, nucleus accumbens, the septum, the bed nucleus of the stria terminalis, the thalamus and several brain stem nuclei. These structural changes are associated with increasing functional connectivity within a network composed by these regions. Moreover, using a clustering based on endocrine and behavioural outcomes, animals were classified as high and low responders to stress. We reveal that susceptible animals (high responders) develop local atrophy of the ventral tegmental area and an increase in functional connectivity between this area and the thalamus, further spreading to other areas that link the cognitive system with the fight-or-flight system. Through a longitudinal approach we were able to establish two distinct patterns, with functional changes occurring during the exposure to stress, but with an inflection point after the first week of stress when more prominent changes were seen. Finally, our study revealed differences in functional connectivity in a brainstem-limbic network that distinguishes resistant and susceptible responders before any exposure to stress, providing the first potential imaging-based predictive biomarkers of an individual's resilience/vulnerability to stressful conditions.

Use of ractopamine during compensatory gain of finishing pigs on carcass and meat performance and quality / Uso de ractopamina durante ganho compensatório de suínos em terminação sobre o desempenho e a qualidade da carcaça e de carne

The objective of this study was to evaluate the effects of compensatory gain associated with the use of 10ppm ractopamine after a period of feed restriction in finishing pigs on performance, carcass and meat quality. Twenty castrated males and 20 females, at 110 days of age and 66.137±6.13kg live weight, were submitted to four treatments using a 2 x 2 factorial design (fed ad libitum or with 20% restriction between 0(21 days of age and fed with or without 10ppm ractopamine for 22(42 days of experimentation), with 10 replicates (animals). There was no interaction between the factors for any of the evaluated parameters. Animals treated with ractopamine presented better weight gain (1.083 versus 1.259kg), feed conversion (2.910 versus 2.577), warm and cold carcass weight (86.08 versus 89.00 and 83.46 versus 87.20kg, respectively), loin depth (63.02 versus 68.40mm), loin eye area (41.43 versus 46.59mm2) and muscle fiber diameter (27.48 versus 35.85µm). Animals submitted to feed restriction followed by ad libitum feed presented compensatory gain without losses to carcass and meat characteristics, but with a reduction in the ethereal extract (2.19 versus 1.64%) and lower water loss due to thawing in the meat (11.35 versus 9.42%). The effects of compensatory gain after food restriction and ractopamine are independent of the parameters evaluated.(AU)

Objetivou-se avaliar os efeitos do ganho compensatório associado ao uso de 10ppm de ractopamina após um período de restrição alimentar, em suínos em terminação, sobre características de desempenho, carcaça e qualidade de carne. Foram utilizados 20 machos castrados e 20 fêmeas, com 110 dias de idade e 66,137±6,13kg de peso vivo, submetidos a quatro tratamentos, fatorial 2 x 2 (alimentação à vontade ou com 20% de restrição entre zero e 21 dias de experimentação; e alimentação à vontade, sem ou com 10ppm de ractopamina, durante 22 a 42 dias de experimentação), com 10 repetições, sendo o animal a repetição. Não houve interação entre os fatores para nenhum dos parâmetros avaliados. Animais tratados com ractopamina apresentaram melhor ganho de peso (1,083 versus 1,259kg), conversão alimentar (2,910 versus 2,577), peso da carcaça quente e fria (86,08 versus 89,00 e 83,46 versus 87,20kg, respectivamente), profundidade do lombo (63,02 versus 68,40mm), área de olho de lombo (41,43 versus 46,59mm2) e diâmetro de fibras musculares (27,48 versus 35,85µm). Animais submetidos à restrição alimentar seguida de arraçoamento ad libitum apresentaram ganho compensatório sem prejuízos às características de carcaça e à carne, mas com redução do extrato etéreo (2,19 versus 1,64%) e menor perda de água por descongelamento na carne (11,35 versus 9,42%) Os efeitos do ganho compensatório após a restrição alimentar e da ractopamina mostram-se independentes sobre os parâmetros avaliados.(AU)

Different Escherichia coli B2-ST131 clades (B and C) producing extended-spectrum ß-lactamases (ESBL) colonizing residents of Portuguese nursing homes.

ESBL-producing Enterobacteriaceae and particularly Escherichia coli ST131 isolates producing CTX-M enzymes are commonly found colonizing the intestine of nursing home (NH) residents, but ST131 subclonal structure has been scarcely explored in this vulnerable population. Our goal was to perform a pilot study to assess the faecal carriage rate and epidemiological features of ESBL- and/or carbapenemase-producing Enterobacteriaceae (ESBL-E and CPE, respectively) among NH residents. For this purpose, faecal samples from residents at 4 different NHs in the North of Portugal (representing 9·5% of the residents' population, July 2014) were screened for ESBL-E and/or CPE by phenotypic and genotypic methods. Clonal structure and plasmid typing of ESBL-producing E. coli (ESBL-Ec) was performed by PCR and sequencing. Four ESBL-Ec isolates (2 CTX-M-15/2 CTX-M-14) were found in 20% of the samples, all belonging to the pandemic clonal lineage B2-ST131-O25b:H4. Two different clades were identified, the C2/H30-Rx-virotype C producing CTX-M-15 and an atypical B/H22-like-virotype D5 (producing CTX-M-14 and fluoroquinolone-resistant), firstly described in Portugal. This pilot study highlights the role of NH residents as a source of different ST131 clades, besides emphasizing the importance of E. coli B2-ST131 subtyping in different clinical settings, and understanding the transmission dynamics of the different variants.

Elucidating constraints for differentiation of major human Klebsiella pneumoniae clones using MALDI-TOF MS.

The establishment of matrix-assisted laser desorption time-of-flight mass spectrometry (MALDI-TOF MS) in routine microbial identification boosted many developments towards high-throughput applications, including bacterial typing. However, results are still controversial for different bacterial species. We aim to evaluate the suitability of MALDI-TOF MS for typing clinically relevant multidrug resistant (MDR) Klebsiella pneumoniae subsp. pneumoniae clones using routine conditions and a previously validated chemometric analysis workflow. Mass spectra of 83 K. pneumoniae clinical isolates representing major human MDR clones [11 sequence types (STs), 22 PFGE-types] recovered in Portugal and Spain during outbreaks and non-outbreak situations (2003-2012) were obtained from cell extracts (CE) and intact cells (IC), and analysed with different chemometric tools. We observed a highly consistent peak pattern among isolates from different clones either with CE or IC, suggesting a high degree of conservation of biomolecules analysed (a large part corresponding to ribosomal proteins). Moreover, the low degree of agreement between MALDI-TOF MS and other methods (from 34.9 % to 43.4 % of correct assignments for CE and from 40.8 % to 70.1 % for IC) corroborates the low discriminatory potential of the technique at infraspecies level. Our results suggest a low discriminatory power of MALDI-TOF MS for clinically relevant MDR K. pneumoniae clones and highlight the need of developing tools for high-resolution typing in this species.

[Single-family rooms for neonatal intensive care units impacts on preterm newborns, families, and health-care staff. A systematic literature review]. / Les chambres familiales en néonatologie : effets sur le nouveau-né prématuré, ses parents et l'équipe soignante. Revue systématique de la littérature.

The quality of the environment is an essential point in the care of preterm newborns. The design of neonatal intensive care units (NICUs) (open-bay, single-patient room, single-family room) directly affects both the preterm newborns and their caregivers (parents, healthcare staff). The aim of this systematic review was to evaluate the impact of single-family rooms on the preterm newborn, its parents, and the staff. Single-family rooms improve outcome for the preterm newborn, with increasing parental involvement and better control of the environment (fewer inappropriate stimulations such as high levels of noise and illumination). This kind of NICU design also improves parental and staff satisfaction.

Atypical epidemiology of CTX-M-15 among Enterobacteriaceae from a high diversity of non-clinical niches in Angola.

OBJECTIVES: The objective of this study was to investigate the distribution and molecular epidemiology of ESBLs, acquired AmpCs and carbapenemases in Enterobacteriaceae from non-clinical niches in Angola, an under-researched sub-Saharan country. METHODS: Eighty-one samples were recovered from healthy persons (n = 18), healthy animals (n = 33) and their environments (n = 10) or aquatic settings (n = 20) in south Angola (2013). Samples were plated onto CHROMagar™ Orientation with/without antibiotics. Standard methods were used for bacterial identification, characterization of bla genes, antibiotic susceptibility testing and conjugation assays. Clonal analysis (XbaI-PFGE, MLST and Escherichia coli phylogroups), location of bla and plasmid characterization (S1-PFGE, I-CeuI-PFGE, replicon typing and hybridization) were also performed. RESULTS: ESBLs (almost exclusively CTX-M-15, 98%) were detected in 21% (45/216) of the isolates, recovered from diverse non-clinical niches and belonging to different Enterobacteriaceae species (mainly E. coli). Acquired AmpCs or carbapenemases were not found. The pandemic B2-ST131 E. coli clone was not identified, but some widespread clonal complexes (CCs) from A (CC10 and CC168), B1 (CC156) or D (CC38) phylogroups were detected. blaCTX-M-15 was variably identified on typeable (29%; 100-335 kb; IncFII, IncFIIK6, IncHI2 and IncY) or non-typeable (16%; 70-330 kb) plasmids or on the chromosome (14%), while for 41% of the isolates its specific location was not determined. CONCLUSIONS: This study reports, for the first time in Angola, an unexpected high occurrence of CTX-M-15 in diverse non-clinical niches and Enterobacteriaceae species, and uncovers novel plasmid replicons in under-researched geographical regions. The diffusion of blaCTX-M-15 through such a high diversity of genetic backgrounds (clones, typeable/non-typeable plasmids and genetic environments) unveils an extraordinary ability for blaCTX-M-15 acquisition and mobilization favoured by unrecognized ecological factors.

Factors affecting the daily feed intake and feed conversion ratio of pigs in grow-finishing units: the case of a company.

BACKGROUND: The aim of this study was to use mathematical modeling to identify and quantify the main factors that affect daily feed intake (DFI) and feed conversion ratio (FCR) in grow-finishing (GF) pig units. We evaluated the production records of 93 GF farms between 2010 and 2013, linked to a company, working in a cooperative system, located in western Paraná State, Brazil. A total of 683 batches, consisting of approximately 495,000 animals, were used. Forty production factors related to the management, health, plant and equipment, nutrition, genetics and environment were considered. The number of pigs per pen, type of feeder, origin and sex (the last two variables were combined in the models) of the animals and initial and final body weights were included in the final models to predict DFI and FCR (dependent variables). Additionally, the duration of the GF phase was included for the parameter FCR. All factors included in the final models had significant effects for both dependent variables. RESULTS: There was a reduction in DFI (0.04 kg) (P < 0.001) and an improvement in FCR (6.0 points) (P < 0.001) in batches from pens with less than 20 animals compared with batches from pens with more than 20 animals. In barns with "other" feeder types (mostly the linear dump type) different of conical semiautomatic feeder, a reduction of DFI (0.03 kg) (P < 0.05) and improved FCR (3.0 points) (P < 0.05) were observed. Batches of barrows from units specialized for producing piglets (SPU) had higher DFI (approximately 0.02 kg) (P < 0.01) than batches of females and batches of mixed animals from SPU, and batches of mixed animals from farms not specialized for piglet production (farrow-to-finish farms). Batches of females from SPU and mixed batches from SPU had better FCR (5.0 and 3.0 points respectively) (P < 0.001 and P < 0.001, respectively) than batches of piglets originating from farrow-to-finish farms. The variables selected for the final models explained approximately 50 and 64 % of the total variance in DFI and FCR, respectively. CONCLUSIONS: The models are tools for the interpretation of the factors related to the evaluated parameters, aiding in the identification of critical aspects of production. The main parameters affecting DFI and FCR in this company during the GF period were the number of pigs per pen, the type of feeder used and the combination origin-sex of the animals.

[Takotsubo cardiomyopathy in an adolescent girl]. / Cardiomyopathie de type tako-tsubo chez une adolescente.

We report the case of a 14-year-old girl who presented with symptoms of left ventricular systolic failure following the rupture of a cerebellar arteriovenous malformation. Takotsubo cardiomyopathy needs to be recognized by pediatricians because the triggering factors, such as physical or emotional stress, are common during childhood. Echocardiography showed a typical dyskinesia of the left ventricular apical or midventricular segments with a hyperkinetic basal region. Symptomatic treatment may be necessary in cases of hypotension, arrhythmias, or acute heart failure. As the prognosis is generally good, reassuring information can be given and cardiologic investigations limited.

MALDI-TOF mass spectrometry as a tool for the discrimination of high-risk Escherichia coli clones from phylogenetic groups B2 (ST131) and D (ST69, ST405, ST393).

Reliable, quick and low-cost methods are needed for the early detection of multidrug-resistant and highly virulent high-risk B2 and D Escherichia coli clones or clonal complexes (HiRCC). Matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI-TOF MS) seems to have a good discriminatory potential at different subspecies levels, but it was never evaluated for the discrimination of E. coli clones. We assessed the potential of MALDI-TOF MS coupled to multivariate data analysis to discriminate representative E. coli B2 and D HiRCC. Seventy-three E. coli isolates from B2 (including ST131 and B2 non-ST131 clones) and D (ST69, ST393, ST405) with variable pulsed-field gel electrophoresis (PFGE) patterns, origins and dates (1980-2010) were tested. MS spectra were acquired from independent extracts obtained from different plate cultures in two different Microflex LT MALDI-TOF devices (Bruker) after a standard extraction procedure. MALDI-TOF MS fingerprinting analysis revealed a good discriminatory ability between the four HiRCC analysed (ST131, ST69, ST405, ST393) and between B2 ST131 and other B2 non-ST131 isolates. Clusters defined by MALDI-TOF MS were consistent with the clonal complexes assigned by multilocus sequence typing (MLST), although differences were detected regarding the composition of clusters obtained by the comparison of PFGE profiles. We demonstrate, for the first time, that characteristic mass fingerprints of different E. coli HiRCC are sufficiently discriminatory and robust to enable their differentiation by MALDI-TOF MS, which might represent a promising tool for the optimisation of infection control, individual patient management and large-scale epidemiological studies of public health relevance. The good correlation between phenotypic and genotypic features further corroborates phylogenetic relationships delineated by MLST.

Long-term dissemination of acquired AmpC ß-lactamases among Klebsiella spp. and Escherichia coli in Portuguese clinical settings.

We investigated the occurrence, diversity and molecular epidemiology of genes coding for acquired AmpC ß-lactamases (qAmpC) among clinical isolates of Enterobacteriaceae lacking inducible chromosomal AmpCs in Portugal. A total of 675 isolates non-susceptible to broad-spectrum cephalosporins obtained from four hospitals and three community laboratories during a 7-year period (2002-2008) were analysed. The presence of genes coding for qAmpC was investigated by phenotypic criteria, polymerase chain reaction (PCR) and sequencing. Bacterial identification, antibiotic susceptibility testing, conjugation assays and clonal analysis were performed by standard procedures. The presence of bla(qAmpC) genes was detected in 50 % (50/100; 41 Klebsiella pneumoniae, 5 Escherichia coli, 4 Klebsiella oxytoca) of the presumptive qAmpC producers. DHA-1, detected in those species, was the most prevalent qAmpC (94 %, 47/50), being identified since 2003 and throughout the studied period in different institutions. Despite the high clonal diversity observed, three DHA-1-producing Klebsiella spp. clones were more frequently identified. CMY-2 (6 %, 3/50) was observed in B1-E. coli clones. Conjugative transfer was only observed in one (2 %) CMY-2-producing isolate. Most qAmpC producers (94 %, 47/50) co-expressed SHV-type and/or OXA-1 or CTX-M-32 extended-spectrum ß-lactamases (ESBLs). To the authors' knowledge, this is the first description of the molecular epidemiology and the long-term dissemination of qAmpC-producing Enterobacteriaceae in Portuguese clinical settings, highlighting an evolution towards a more complex epidemiological situation regarding cephalosporin resistance in Portugal.

Spread of an OmpK36-modified ST15 Klebsiella pneumoniae variant during an outbreak involving multiple carbapenem-resistant Enterobacteriaceae species and clones.

We aim to characterise multiple ertapenem-resistant (ERT-R, n = 15) Enterobacteriaceae isolates identified as presumptive carbapenemase producers in a Portuguese hospital in a short period of time (March-July 2010). Antibiotic susceptibility patterns, ß-lactamases, genetic relatedness [pulsed-field gel electrophoresis (PFGE), multi-locus sequence typing (MLST)], plasmid content and major enterobacterial porins were investigated. Ertapenem resistance was associated with deficiencies in major porins and, in some cases, extended-spectrum ß-lactamase (ESBL) or AmpC ß-lactamase production among outbreak and non-outbreak clones. Most isolates (n = 8) corresponded to two ERT-R Klebsiella pneumoniae ST15 PFGE-types: (i) a sporadic variant (Kp-A-ERT, n = 1) presenting a premature stop codon in ompK36 and (ii) an epidemic variant (Kp-B-ERT, n = 7) exhibiting a new OmpK36 porin variant, which differed additionally in plasmid and antibiotic susceptibility profiles. ST14 (n = 1) and ST45 (n = 1) K. pneumoniae, ST131 (n = 1) and ST354 (n = 1) Escherichia coli, Enterobacter asburiae (n = 1), Enterobacter cloacae (n = 1) and Enterobacter aerogenes (n = 1) ERT-R clones were also sporadically detected. Porin changes in these isolates included non-sense mutations [ompK35, ompK36, ompF; minimum inhibitory concentration (MIC) = 4-32 mg/l], IS-mediated porin disruptions (ompK36, ompC; MIC = 12->32 mg/l) or alterations in the L3 loop (ompK36; MIC = 4-16 mg/l). We describe, for the first time in Portugal, the simultaneous emergence of multiple ERT-R Enterobacteriaceae species and clones in a short period of time. Moreover, our results support that a CTX-M-15-producing ST15 K. pneumoniae with an OmpK36-modified porin might successfully spread in the nosocomial setting.

Prevalence and spread of extended-spectrum beta-lactamase-producing Enterobacteriaceae in Europe.

Extended-spectrum beta-lactamases (ESBLs) represent a major threat among resistant bacterial isolates. The first types described were derivatives of the TEM-1, TEM-2 and SHV-1 enzymes during the 1980s in Europe, mainly in Klebsiella pneumoniae associated with nosocomial outbreaks. Nowadays, they are mostly found among Escherichia coli isolates in community-acquired infections, with an increasing occurrence of CTX-M enzymes. The prevalence of ESBLs in Europe is higher than in the USA but lower than in Asia and South America. However, important differences among European countries have been observed. Spread of mobile genetic elements, mainly epidemic plasmids, and the dispersion of specific clones have been responsible for the increase in ESBL-producing isolates, such as those with TEM-4, TEM-24, TEM-52, SHV-12, CTX-M-9, CTX-M-14, CTX-M-3, CTX-M-15 and CTX-M-32 enzymes.

Prevalence of DEA 1 canine blood group system in dogs (Canis familiaris, Linnaeus, 1758) reared in Brazil

Up to the present, the DEA 1 system has been regarded as the most important dog blood group as far as blood transfusion is concerned. It occurs because the DEA 1 system is highly antigenic and may elicit the production of alloantibodies in a DEA 1 negative recipient, following a transfusion with DEA 1 positive red cells. As a consequence, the recipient will develop a hemolytic transfusion reaction if it receives a second transfusion with DEA 1 type cells. The frequency of appearance of the DEA 1 system is well known in other countries but no information was available for dogs reared in Brazil. In the present experiment 150 dogs were typed, using specific reagents purchased from "The Immunohematology and Serology Laboratory" of Michigan State University, in order to clarify the prevalence of the DEA 1 system (1.1 and 1.2 subgroups) in pure breeds and mongrel dogs reared in Brazil and referred to the Veterinary Hospital of Sao Paulo State University. The results obtained showed a general prevalence of 91.3 per cent for the DEA 1 system, comprising 51.3 per cent of DEA 1.1 type dogs, while 40 per cent of the animals were positive for DEA 1.2 type. Only 8.7 per cent of tested dogs were negative for DEA 1 system. The prevalence found in this study for dogs reared in Brazil is higher than those ones, described by foreign authors, for dogs reared in other countries. Moreover, through a statistic study, it was found that the potential risk for the occurrence of a hemolytic transfusion reaction in a mongrel dog reared in Brazil is minimum