Abstract INTRODUCTION In recent decades, the prevalence of carbapenem-resistant Acinetobacter isolates has increased, and the production of oxacillinase (OXA)-type carbapenemases is the main mechanism underlying resistance. We evaluated OXA production from 114 Acinetobacter isolates collected between March and December 2013 from different clinical specimens of patients in two hospitals (Hospital 1 [n = 61] and Hospital 2 [n = 53]) located in Niterói, Rio de Janeiro, Brazil. We also evaluated the genetic diversity of OXA-producing isolates. METHODS All the isolates were identified through the automated system Vitek II and matrix-assisted laser desorption ionization-time of flight mass spectrometry MALDI-TOF MS as belonging to the A. baumannii-A. calcoaceticuscomplex. Antimicrobial susceptibility profiles were verified through agar diffusion tests. The presence of OXA-encoding genes was confirmed by PCR. The genetic diversity of isolates positive for carbapenemase production was analyzed through pulsed-field gel electrophoresis. RESULTS There was a high rate of resistance to carbapenems in the isolates (imipenem: 96%; meropenem: 92%) from both hospitals. Moreover, a high percentage (95.6%) of OXA-23-positive isolates was observed for both hospitals, indicating that this was the main mechanism of carbapenem-resistance among the studied population. In addition, most isolates (96.5%) were positive for bla OXA-51. A high genetic diversity and a few major genotypes were found among the OXA-23-positive isolates analyzed. Only intra-hospital dissemination was observed. CONCLUSIONS The elevated dissemination of bla OXA-23-like observed among Acinetobacter isolates from both the studied hospitals highlights the need for continuous epidemiological surveillance in these institutions.

Abstract Purpose: To evaluate whether combining hypothermia and remote ischemic preconditioning (RIPC) results in protection from ischemia-reperfusion (IR). Methods: Thirty-two Wistar rats underwent right nephrectomy and were randomly assigned to four experimental protocols on the left kidney: warm ischemia (group 1), cold ischemia (group 2), RIPC followed by warm ischemia (group 3), and RIPC followed by cold ischemia (group 4). After 240 minutes of reperfusion, histological changes in the left kidney, as well as lipid peroxidation and antioxidant enzyme activity, were analyzed. The right kidney was used as the control. Serum creatinine was collected before and after the procedures. Results: RIPC combined with hypothermia during IR experiments revealed no differences on interventional groups regarding histological changes (p=0.722). Oxidative stress showed no significant variations among the groups. Lower serum creatinine at the end of the procedure was seen in animals exposed to hypothermia (p<0.001). Conclusions: Combination of RIPC and local hypothermia provides no renal protection in IR injury. Hypothermia preserves renal function during ischemic events. Furthermore, RIPC followed by warm IR did not show benefits compared to warm IR alone or controls in our experimental protocol.

Abstract Purpose: To evaluate whether their combination was more effective than either alone in decreasing renal damage due to ischemia/reperfusion (I/R) injury in rats. Methods: Thirty-two Wistar rats were assigned to four groups. Following right nephrectomy, their left kidneys were subjected to warm ischemia (IR), cold ischemia (TH+IR), intraperitoneal injection of 10 mg/kg melatonin (MEL+IR), or injection of 10 mg/kg melatonin followed by cold ischemia (MEL+TH+IR). Eight randomly assigned right kidneys constituted the control group. After 240 min of reperfusion, left nephrectomy was performed for histopathological evaluation, lipid peroxidation, and measurement of antioxidant enzyme activity. Serum was collected to measure urea and creatinine concentrations. Results: Histopathological damage induced by ischemia and reperfusion was more attenuated in the MEL+TH+IR group than in the MEL+IR and TH+IR groups (p<0.037). Superoxide dismutase activity was significantly higher (p<0.029) and creatinine (p<0.001) and urea (p<0.001) concentrations were significantly lower in the MEL+TH+IR group than in the MEL+IR and TH+IR groups. Conclusion: The combination of melatonin (MEL) and topical hypothermia (TH) better protects against renal I/R injury than does MEL or TH alone.

Abstract Purpose: Topical hypothermia and local ischemic preconditioning have been shown to reduce renal ischemia-reperfusion (I/R) injury individually. We examined whether combination of both strategies lessens renal I/R injury. Methods: Post right nephrectomy, 40 male Wistar rats were randomly assigned to five experimental protocols performed in the left kidney: topical hypothermia without ischemia (TH), warm ischemia (IR), ischemic preconditioning followed by warm ischemia (IPC+IR), cold ischemia (TH+IR), and ischemic preconditioning followed by cold ischemia (IPC+TH+IR). Eight randomly assigned right kidneys constituted the control group. After 240 min of reperfusion, the left kidney was retrieved to evaluate histological changes, lipid peroxidation and antioxidant enzymes activity. Serum was collected to evaluate urea and creatinine. Results: IPC+TH+IR group revealed no difference to any other group subjected to ischemia in relation to histological changes, lipid peroxidation and antioxidant enzymes activity. Creatinine was lower in IPC+TH+IR group compared with IPC+IR, but showed no difference compared to TH+IR group. Conclusions: Combination of local ischemic preconditioning (IPC) and topical hypothermia conferred no protection in renal I/R injury. Moreover, local IPC solely followed by warm ischemia impaired renal function more than warm ischemia alone.

RESUMO Contexto As complicações inerentes de cirrose incluem a desnutrição proteico-calórica e deficiências de micronutrientes. Alterações no paladar são prejudiciais para o estado nutricional e o mecanismo para explicar essas mudanças não é bem documentada nos pacientes cirróticos. Objetivo Avaliar as papilas gustativas de ratos cirróticos. Métodos Foram avaliados 14 ratos Wistar machos. Após 16 semanas, o fígado foi removido para diagnosticar histologicamente cirrose, e o sangue foi colhido para efetuar testes de integridade hepática. A língua foi removida para exame histológico e imuno-histoquímica utilizando anticorpos contra o gene da proteína PGP 9.5 e os receptores de sabor doce T1R2 e T1R3. As alterações morfológicas foram determinadas por microscopia eletrônica de varredura e os níveis de zinco no soro foram medidos. Resultados Os animais cirróticos, em relação aos animais controle, apresentaram deficiência de zinco significativa. Em ambos os grupos, houve imunorreatividade positiva para o tipo II e células III e receptores T1R2. Os animais cirróticos não tinham imunoreactividade para receptores T1R3. Microscopia eletrônica de varredura do grupo cirrótico revelou um afilamento uniforme das papilas gustativas. Conclusão O modelo de cirrose experimental imitou os parâmetros bioquímicos e histológicos de cirrose humana, portanto, permitindo um estudo das papilas gustativas e paladar.

ABSTRACT Background The inherent complications of cirrhosis include protein-calorie malnutrition and micronutrient deficiencies.Changes in taste are detrimental to the nutritional status, and the mechanism to explain these changes is not well documented in the cirrhotic patients. Objective To evaluate the taste buds of cirrhotic rats. Methods Fourteen male Wistar rats were evaluated. After 16 weeks, the liver was removed to histologically diagnose cirrhosis, and blood was collected to perform liver integrity tests. The tongue was removed for histological examination and immunohistochemistry using antibodies against protein gene product PGP 9.5 and the sweet taste receptors T1R2 and T1R3. Morphological changes were determined by scanning electron microscopy. Serum zinc levels were measured. Results The cirrhotic animals, but not the control animals, exhibited zinc deficiency. In both groups, there was positive immunoreactivity for type II and III cells and T1R2 receptors. The cirrhotic animals had no immunoreactivity for T1R3 receptors. Scanning electron microscopy analysis of the cirrhotic group revealed a uniform tapering of the gustatory papillae. Conclusion In conclusion the experimental cirrhosis model mimicked the biochemical and histological parameters of human cirrhosis, therefore enabling a study of the gustatory papillae and taste buds.

Abstract BACKGROUND: Although dermatophytes are considered the major cause of onychomycosis, many reports have incriminated non-dermatophyte moulds and yeasts in the disease’s etiology. Successive Trichosporon isolation from onychomycosis has led to the genus being suspected as a nail primary pathogen. OBJECTIVE: To determine the prevalence of Trichosporon isolation in onychomycosis patients who attended a mycology diagnostic service in Rio de Janeiro, Brazil, between January 2003 and December 2006. The study also includes a worldwide review on Trichosporon isolation prevalence in ungueal disease, emphasizing T. ovoides. METHODS: This retrospective study was conducted with the support of staff from the Mycology Laboratory at the Dermatological Service of Rio de Janeiro’s Santa Casa da Misericórdia (MLDS). RESULTS: Mycological analysis provided positive results equaling 47/5036 (0.93%) for Trichosporon spp.; obtained mainly as a single agent (72.35%), and from mixed cultures (27.65%; X2= 6.397; p= 0.018). The great majority belongs to the T. ovoides species (91.5%; n=43), obtained as a single isolate (74.41%; n= 32/43; X2 = 7.023; p= 0.014). CONCLUSIONS: Although T. ovoides is classically associated as an etiologic agent of white piedra, this study highlights its potential as a human nail disease pathogen. Our study opens doors for future epidemiologic and virulence factors aimed at determining whether T. ovoides is an important causative agent of onychomycosis in Brazil.

The isolation of mannitol-negative methicillin-resistant Staphylococcus aureus from nasal swabs is reported. Among the 59 isolates, 9 (15%) isolates were mannitol-negative; all of these isolates were categorized as staphylococcal cassette chromosome mec (SCCmec) type IVa. This report emphasizes that mannitol fermentation on mannitol salt agar should not be used as the sole criterion when screening nasal swab specimens for S. aureus.

INTRODUCTION: Acquired production of metallo-β-lactamases is an important mechanism of resistance in Pseudomonas aeruginosa. The objective of this study was to investigate the production of metallo-β-lactamase and the genetic diversity among ceftazidime-resistant P. aeruginosa isolates from State of Sergipe, Brazil. METHODS: Metallo-β-lactamase was investigated using the disk approximation test and polymerase chain reaction (PCR). Genetic diversity was evaluated by pulsed-field gel electrophoresis (PFGE). RESULTS: A total of 48 (51.6%) isolates were resistant to ceftazidime. Six (12.2%) of these were positive for metallo-β-lactamase production. Only two (4.1%) of the ceftazidime-resistant isolates carried the bla SPM-1 gene. CONCLUSIONS: Production of metallo-β-lactamases was not the main mechanism of resistance to ceftazidime and carbapenems among P. aeruginosa strains in Sergipe, Brazil.

Introduction  The ideal animal model for nerve regeneration studies is the object of controversy, because all models described by the literature have advantages and disadvantages. Objective  To describe the histologic and functional patterns of the mandibular branch of the facial nerve of Wistar rats to create a new experimental model of facial nerve regeneration. Methods  Forty-two male rats were submitted to a nerve conduction test of the mandibular branch to obtain the compound muscle action potential. Twelve of these rats had the mandibular branch surgically removed and submitted to histologic analysis (number, partial density, and axonal diameter) of the proximal and distal segments. Results  There was no statistically significant difference in the functional and histologic variables studied. Conclusion  These new histologic and functional standards of the mandibular branch of the facial nerve of rats establish an objective, easy, and greatly reproducible model for future facial nerve regeneration studies.

PURPOSE:To design an animal model of ischemia-reperfusion (I/R) in kidneys and evaluate the role that predetermined ranges of local hypothermia plays on markers of stress-oxydative as well as on histologic sections. METHODS: Twenty eight male rats Wistar, under general anesthesia, undergone right nephrectomy (G0, control group) followed by left kidney ischemia during 40 min. Four temperatures groups were designed, with seven animals randomized for each group: normothermic (G1, ±37ºC), mild hypothermia (G2, 26ºC), moderate hypothermia (G3, 15ºC) and deep hypothermia (G4, 4ºC). Left kidney temperature was assessed with an intraparenchymal probe. Left nephrectomy was performed after 240 min of reperfusion. After I/R a blood sample was obtained for f2-IP. Half of each kidney was sent to pathological evaluation and half to analyze CAT, SOD, TBARS, NO3, NO2. RESULTS:Histopathology showed that all kidneys under I/R were significantly more injured than the G0 (p<0.001). TBARS had increased levels in all I/R groups compared with the G0 (p<0.001). CAT had a significant difference (p<0.03) between G1 and G4. Finally, no difference was found on SOD, NO3, NO2 nor on f2-IP. CONCLUSION: This model of I/R was efficient to produce oxidative-stress in the kidney, showing that 4ºC offered significant decrease in free radicals production, although tissue protection was not observed.

Tobacco farmers are routinely exposed to complex mixtures of inorganic and organic chemicals present in tobacco leaves. In this study, we examined the genotoxicity of tobacco leaves in the snail Helix aspersa as a measure of the risk to human health. DNA damage was evaluated using the micronucleus test and the Comet assay and the concentration of cytochrome P450 enzymes was estimated. Two groups of snails were studied: one fed on tobacco leaves and one fed on lettuce (Lactuca sativa L) leaves (control group). All of the snails received leaves (tobacco and lettuce leaves were the only food provided) and water ad libitum. Hemolymph cells were collected after 0, 24, 48 and 72 h. The Comet assay and micronucleus test showed that exposure to tobacco leaves for different periods of time caused significant DNA damage. Inhibition of cytochrome P450 enzymes occurred only in the tobacco group. Chemical analysis indicated the presence of the alkaloid nicotine, coumarins, saponins, flavonoids and various metals. These results show that tobacco leaves are genotoxic in H. aspersa and inhibit cytochrome P450 activity, probably through the action of the complex chemical mixture present in the plant.

INTRODUCTION: Acinetobacter spp. have emerged as notorious pathogens involved in healthcareassociated infections. Carbapenems are important antimicrobial agents for treating infections due to multidrug resistant Acinetobacter spp. Different mechanisms may confer resistance to these drugs in the genus, particularly production of class D carbapenemases. OXA-23-like family has been pointed out as one of the predominant carbapenamases among Acinetobacter. The present work aimed to investigate the occurrence of OXA-23-like carbapenemases among Acinetobacter isolates recovered from patients of a university hospital in Niterói, RJ, Brazil. METHODS: Antimicrobial susceptibility profiles were determined by disk-diffusion. Imipenem resistant isolates were submitted to Modified Hodge Test in order to screen for carbapenemase production, and later to polymerase chain reaction (PCR) to investigate the presence of blaOXA-23. RESULTS: Imipenem and meropenem resistance rates were 71.4% and 69.7%, respectively. The Modified Hodge Test revealed carbapenemase production among 76 (89.4%) of the 85 imipenem resistant isolates analyzed; according to PCR results, 81 isolates (95.4%) carried the blaOXA-23 gene. CONCLUSIONS: OXA-23-like enzymes may be an important mechanism of carbapenem resistance among isolates present in the hospital studied.

OBJECTIVES: This in vitro study evaluated the effectiveness of three carbamide peroxide concentrations used for tooth bleaching treatments. MATERIAL AND METHODS: Sixty bovine dental slabs (6x6x3 mm) were obtained, sequentially polished, submitted to artificial staining (baseline) and randomized into four groups (n=15), according to the bleaching agent concentration: distilled water (control), 10% (CP10), 16% (CP16) or 37% (CP37) carbamide peroxide. CP10 and CP16 were covered with 0.2 mL of the respective bleaching gels, which were applied on enamel surface for 4 h/day during two weeks. Samples of CP37 were covered with 0.2 mL of the bleaching gel for 20 min. The gel was light activated by two 40-s applications spaced by 10-min intervals. The gel was renewed and applied 3 times per clinical session. This cycle was repeated at 3 sessions with 5 days of interval between them. Tooth shade evaluations were done with a digital spectrophotometer at T0 (baseline), T1 (after 1-week of treatment) and T2 (1-week post-bleaching). Tooth shade means were statistically analyzed by Kruskal-Wallis and Friedman's tests and color parameters were analyzed by two-way ANOVA and Tukey's test (p<0.05). RESULTS: At T1 and T2 evaluations, tooth shade was significantly lighter than at baseline for all treatment groups, considering the color parameters ΔL*, Δa*, Δb*, ΔE* (p<0.001) or tooth shade means (p<0.001). CP37 group showed lower shade mean change than CP10 and CP16 at T1 (p<0.01), but this difference was not statistically significant at T2 (p>0.05). CONCLUSIONS: One week after the end of the treatment, all carbamide peroxide concentrations tested produced similar tooth color improvement.

OBJETIVO: A ventilação mecânica constitui um dos pilares terapêuticos da unidade de terapia intensiva, entretanto, deve-se avaliar os efeitos deletérios por ela ocasionados, logo objetivamos avaliar o estresse oxidativo de pacientes internados em unidade de terapia intensiva submetidos à ventilação mecânica invasiva. MÉTODOS: Estudo transversal onde foram incluídos 12 pacientes que estavam em ventilação mecânica invasiva. As coletas sanguíneas (3 mL) foram realizadas no primeiro e último dia em que o paciente estava submetido a ventilação mecânica invasiva e utilizou-se o plasma para avaliação das substâncias que reagem ao ácido tiobarbitúrico (TBARS) e os glóbulos vermelhos para dosagem de superóxido dismutase (SOD) e da catalase. RESULTADOS: Os pacientes apresentaram média de idade de 64,8±17,6 anos; volume corrente de 382±44,5 mL e APACHE II de 15±7. Quando comparado o TBARS inicial e ao final da ventilação houve diferença significativa (3,54±0,74 vs. 4,96±1,47; p=0,04). Em relação às enzimas antioxidantes não houve diferença. Observa-se correlação entre as variáveis PaO2/FiO2 e TBARS (r = 0,4); SOD e PaO2/FiO2 (r = 0,51) e SOD e APACHE II (r = 0,56). Quanto ao desfecho da internação, 6 pacientes foram a óbito. CONCLUSÃO: Pacientes submetidos à ventilação mecânica invasiva podem apresentar alteração do estado redox, marcado pelo aumento no TBARS e redução das enzimas antioxidantes.

OBJECTIVE: Mechanical ventilation is a mainstay of therapy in intensive care units; however, its deleterious effects need to be assessed. Therefore, we aimed to assess oxidative stress in patients admitted to an intensive care unit undergoing invasive mechanical ventilation. METHODS: This cross-sectional study included 12 invasive mechanical ventilation patients. Blood samples (3 mL) were collected on the first and last days on invasive mechanical ventilation. Thiobarbituric acid-reacting substances (TBARS) were assessed in plasma, and superoxide dismutase (SOD) and catalase (CAT) were assessed in erythrocytes. RESULTS: The mean age was 64.8 ± 17.6 years, the tidal volume (VT) 382 ± 44.5 mL, and the APACHE II score 15 ± 7. When initial and final TBARS were compared, a significant difference was identified (3.54 ± 0.74 vs. 4.96 ± 1.47, p = 0.04). Antioxidant enzymes showed no significant differences. Correlations between PaO2/FiO2 and TBARS (r = 0.4), SOD and PaO2/FiO2 (r = 0.51) and APACHE II and SOD (r = 0.56) were identified. Six patients died. CONCLUSION: Patients undergoing invasive mechanical ventilation can develop redox state changes, showing increased TBARS and reduced antioxidant enzymes.