Abstract INTRODUCTION: Coagulase-negative staphylococci (CoNS) are a frequent cause of bacteremia, especially in neonates. The major virulence determinant in CoNS is the ability to produce biofilms, which is conferred by the icaADBC genes. This study aimed to assess different methods for the detection of biofilm formation in 176 CoNS isolates from blood cultures of newborns. METHODS: The presence of the icaACD genes was assessed by polymerase chain reaction (PCR), and biofilm formation was assessed on congo red agar (CRA), by the tube method (TM), and on tissue culture plates (TCP). RESULTS: Of the 176 CoNS isolates, 30.1% expressed icaACD and 11.4% expressed icaAD. The CRA assay and TM showed that 42% and 38.6% of the isolates were biofilm producing, respectively. On TCP, 40.9% of the isolates produced biofilms; 21% were weakly adherent and 19.9% were strongly adherent. When compared to the gold standard technique (PCR), the CRAassay showed 79% sensitivity and 84% specificity (kappa = 0.64), TM showed 78% sensitivity and 89% specificity (kappa = 0.68), and TCP showed 99% sensitivity and 100% specificity (kappa = 0.99). CONCLUSIONS: In this study, ~42% of CoNS isolates produced biofilms, and the presence of icaACD was associated with a greater capacity to form biofilms. Compared to the other phenotypic methodologies, TCP is an ideal procedure for routine laboratory use.

Abstract Objectives A single-blinded, randomized, parallel clinical trial evaluated the use of 37% carbamide peroxide (CP) on bleaching effectiveness and tooth sensitivity reported by patients undergoing in-office tooth bleaching, in comparison with the results of using 35% hydrogen peroxide. Material and Methods Forty patients were allocated to receive two sessions of in-office tooth bleaching using either 35% hydrogen peroxide (HP) or 37% CP. Each patient’s sensitivity level was evaluated during and up to 24 h after bleaching. The effectiveness of the bleaching procedures was evaluated with a spectrophotometer one week after each session and 30 days after the last session. The impact of tooth bleaching on the patients’ perceptions regarding smile changes, in addition to the bleaching procedures and their results, were also recorded. Absolute and relative sensitivity risks were calculated. Data on sensitivity level were analyzed using the Mann-Whitney or T-test, and data from the color evaluation were subjected to 2-way repeated measures ANOVA. Results The use of CP reduced the risk and level of tooth sensitivity to values close to zero, whereas the difference between the bleaching agents disappeared after 24 h. An increased bleaching effect was observed for HP, mainly due to an improved reduction of redness and yellowness. Participants perceived improved tooth bleaching for HP and reduced sensitivity for CP, but no differences regarding the comfort of the techniques were noted. Conclusions In our study, 37% CP resulted in reduced tooth sensitivity but decreased the tooth bleaching effectiveness. However, both bleaching agents resulted in high levels of patient satisfaction.

Abstract The treatment of infections caused by resistant microorganisms represents a big challenge in healthcare due to limited treatment options. For this reason, the discovery of new active substances which are able to perform innovative and selective actions is of great impact nowadays. Statins and triazenes (TZC) have consolidated as a promising class of compounds, characterized by the expressive biological activity, especially antimicrobial activities. The aim of this study was to assess the in vitro synergistic antibacterial effect of the association of statins and a new TZC complex {[1-(4-bromophenyl)-3-phenyltriazene N 3-oxide-κ 2 N 1,O 4](dimethylbenzylamine-κ 2 C 1,N 4)palladium(II)} (Pd(DMBA)LBr) against American Type Culture Collection (ATCC) strains and clinical isolates. The complex and the statins showed bacterial activity of all tested strains and clinical isolates, evidencing that TZC complexion with metals can be promising. Simvastatin showed synergy when associated to the complex (FICI≤0.5), being the minimum inhibitory concentration (MIC) of 16 µg mL-1 found in 6 samples. Thus, it is possible to infer that the association between Pd(DMBA)LBr and simvastatin consists of an alternative to increase the pontential of these compounds, since statins have low toxicity.

Abstract INTRODUCTION: The rapid global spread of carbapenem-resistant Enterobacteriaceae (CRE) is a threat to the health system. METHODS: We evaluated the antimicrobial susceptibility profiles of 70 CRE isolated in a tertiary hospital in Brazil between August and December 2015, and determined their resistance mechanisms. RESULTS: The most prevalent microorganism was Klebsiella pneumoniae (95.7%); it showed high-level resistance to carbapenems (>98%), with sensitivity to colistin (91.4%) and amikacin (98.6%). The bla KPC gene was detected in 80% of the CRE isolates. CONCLUSIONS: Evaluation of bacterial resistance contributes to an appropriate treatment, and the reduction of morbimortality and dissemination of resistance.

Abstract INTRODUCTION: In this study, we used phenotypic methods to screen carbapenem-resistant Enterobacteriaceae (CREs) and evaluated their antimicrobial sensitivity profile. METHODS: One hundred and seventy-eight CREs were isolated at a university hospital in south Brazil in a one-year period. Samples were assessed using disk diffusion tests with inhibitors of β-lactamases such as phenylboronic acid (AFB), cloxacillin (CLOXA), and ethylenediaminetetraacetic acid (EDTA). Strains with differences in zone diameters ≥ 5mm for disks supplemented or not were considered producers of carbapenemases. RESULTS: Klebsiella pneumoniae was the most prevalent CRE, which appeared in 80.3% cases (n = 143). Among clinical materials, the rectal swab was responsible for 43.4% of the isolations (n = 62), followed by urine (18.9%; n = 27). Among the CREs identified in this study, the growth of 56.7% (n = 101) isolates, which were putative producers of Klebsiella pneumoniae carbapenemase (KPC), were inhibited by AFB, whereas 7.3% (n = 13) isolates were inhibited by both AFB and CLOXA and were considered as putative producers of plasmid-mediated AmpC; approximately 3.4% (n = 6) were inhibited by EDTA, which possibly produced metallo-β-lactamase. Lastly, 32.6% (n = 58) cases showed negative results for AFB, CLOXA, and EDTA sensitivity, and represented another class of β-lactamases and/or mechanism of resistance. CONCLUSIONS: Phenotypic screening of CREs is important for clinical laboratories that monitor outbreaks of resistant microbes. Phenotypic tests that use carbapenemase inhibitors and enhancers such as AFB, CLOXA, and EDTA are necessary since they are good screening methods for the detection of carbapenemases.

RESUMO: O objetivo desse estudo foi avaliar as alterações sistêmicas e neurotóxicas promovidas pelo meloxicam, administrado por via epidural, em coelhos. Foram utilizados 12 coelhos adultos, quatro machos e oito fêmeas, pensando em média 1,9 ± 0,1kg. Os animais foram divididos equitativa e aleatoriamente em dois grupos, os quais receberam dose única de solução de NaCl 0,9% no volume de 0,3mL kg-1, por via epidural (grupo controle - GC) ou meloxicam (0,2mg kg-1) associado à solução de NaCl 0,9%, compondo um volume total de 0,3mL kg-1 (grupo meloxicam - GM). Avaliaram-se frequências cardíaca e respiratória, temperatura corporal e alterações neurológicas, antes da administração da anestesia (H0), uma, duas, três, seis, 12 e 24 horas após a punção epidural (H1, H2, H3, H6, H12 e H24, respectivamente) e a cada 24 horas após o H24, até o 10º dia após a punção epidural (D2, D3, D4, D5, D6, D7, D8, D9 e D10). Mensurou-se ainda a temperatura superficial da região lombossacra em H0, H1, H6, H12, H24, D5 e D10. Realizou-se eutanásia em três animais de cada grupo no 15o e no 30o dia após o início do experimento, para avaliação das possíveis lesões medulares. As variâncias observadas nos parâmetros fisiológicos não foram sugestivas de efeito adverso do meloxicam, pois estiveram dentro do padrão de referência e não houve alterações físicas ou comportamentais. O exame neurológico se mostrou semelhante entre os grupos, havendo diferença apenas entre a avaliação inicial e uma hora após a epidural em ambos os grupos. Na histopatologia não houve alterações no GM e apenas um animal do GC apresentou discreto infiltrado linfoplasmocitário. A administração epidural lombossacra de meloxicam, na dose de 0,2mg kg-1, não causa efeitos sistêmicos e neurotóxicos significativos, em coelhos.

ABSTRACT: The aim of this study was to assess systemic and neurotoxic changes following an epidural administration of meloxicamin to rabbits. Twelve adult rabbits four males and eight females; average mass, 1.9 ± 0.1kg were randomly divided into two groups: a control group (GC), which received a single dose of 0.9% NaCl epidurally in a volume of 0.3mL kg-1and a meloxicam group (GM), which received 0.2mg kg-1 meloxicam epidurally along with 0.9% NaCl in a total volume of 0.3mL kg-1. Heart rate, respiratory rate, body temperature, and neurological abnormalities were assessed prior to administration of anesthesia (H0), 1, 2, 3, 6, 12, and 24h following epidural puncture (H1, H2, H3, H6, H12, and H24, respectively), and every 24h afterward for 10 days after epidural puncture (D2, D3, D4, D5, D6, D7, D8, D9, and D10). The surface temperature of lumbosacral region was also measured at H0, H1, H6, H12, H24, D5 and D10. Three animals from each group were euthanized on days 15 and 30 after epidural puncture to assess possible spinal injuries. Variances observed in physiological parameters were not suggestive of adverse effects of meloxicam, as all were within the reference standards, and there were no physical or behavioral changes observed. Neurological function was similar between groups, with only difference between baseline values and values 1h after epidural administration in both groups. There were no histopathological changes in the GM group, and only one animal showed discrete lymphocytic infiltrate. Epidural lumbosacral administration of meloxicam at a dose of 0.2mg kg-1 caused no significant systemic or neurotoxic effects in rabbits.

Petrolisthes armatus (Gibbes, 1850) is a porcellanid crab with a wide geographical distribution. In the present study we analyzed variations in the abundance of P. armatus adults and larvae over an annual cycle in the Marapanim estuary of the Amazon coastal zone, in the northeastern portion of the state of Pará, Brazil. Particularly, we focused on the presence of ovigerous females and timing of larval release, with the aim of elucidating reproductive patterns in a tropical estuarine system. The mean density of P. armatus larvae (zoea I and II) correlated positively with the salinity of the shallow waters of the estuary, whereas the abundance of adults correlated with the salinity registered in water samples collected from the benthic environment. There was also a significant positive correlation between larval density (zoea I and II) and water temperature. Ovigerous females were captured throughout the study period, from August 2006 to July 2007, but were more abundant in June and less abundant during the rainy months, between February and May. Larvae were only present during the dry season and transition months (June to January), and were absent during the rainy season (February to May). Petrolisthes armatus reproduces throughout the year in the Marapanim estuary and all developmental stages of this species (zoeal stages I and II, megalopae and adults) are found in the estuary. The results indicate that the study area is an important environment for the reproduction of this decapod.