Beyond 5G Fronthaul Based on FSO Using Spread Spectrum Codes and Graphene Modulators.

High data rate coverage, security, and energy efficiency will play a key role in the continued performance scaling of next-generation mobile systems. Dense, small mobile cells based on a novel network architecture are part of the answer. Motivated by the recent mounting interest in free-space optical (FSO) technologies, this paper addresses a novel mobile fronthaul network architecture based on FSO, spread spectrum codes, and graphene modulators for the creation of dense small cells. The network uses an energy-efficient graphene modulator to send data bits to be coded with spread codes for achieving higher security before their transmission to remote units via high-speed FSO transmitters. Analytical results show the new fronthaul mobile network can accommodate up to 32 remote antennas under error-free transmissions with forward error correction. Furthermore, the modulator is optimized to provide maximum efficiency in terms of energy consumption per bit. The optimization procedure is carried out by optimizing both the amount of graphene used on the ring resonator and the modulator's design. The optimized graphene modulator is used in the new fronthaul network and requires as low as 4.6 fJ/bit while enabling high-speed performance up to 42.6 GHz and remarkably using one-quarter of graphene only.

Sequential Sampling Plans for Thrips (Thysanoptera: Thripidae) in Soybean Crops With Insecticide Applications Using Tractor or Airplane.

Sampling plans are an essential part of integrated pest management programs. Sequential sampling plans enable rapid and low-cost assessment of pest densities. Thrips are emerging pests in soybean crops, and the main method used in pest control is chemical. In soybean crops, insecticides are applied mainly using tractors or airplanes. Thus, this work aimed to determine sequential sampling plans for thrips in soybean crops with insecticide applications using a tractor or airplane. Data were collected in 56 soybean fields, and each field was 20 ha. Sampling plans were determined and validated. The lower (m0) and upper (m1) limits of the sequential sampling plans were: m0 = 1.72 and m1 = 3.43 (by tractor applications) and, m0 = 2.27 and m1 = 4.53 thrips. sample-1 (by airplane applications). The slope (S) and the lower (h0) and upper (h1) intercepts of the sequential sampling plans were: S = 2.42, h0 = -5.79, and h1 = 5.79 (by tractor applications) and, S = 3.19, h0 = -6.83, and h1 = 6.83 (by airplane applications). Sequential sampling plans allowed for correct decisions to be made in all situations using a maximum of 10 samples. The sequential plan reduced the sampling effort by over 87% compared to conventional sampling plans. Therefore, these control decision-making systems have proven feasible and advantageous for implementing integrated pest management programs for controlling thrips species in soybean crops.

A long noncoding RNA promotes parasite differentiation in African trypanosomes.

The parasite Trypanosoma brucei causes African sleeping sickness that is fatal to patients if untreated. Parasite differentiation from a replicative slender form into a quiescent stumpy form promotes host survival and parasite transmission. Long noncoding RNAs (lncRNAs) are known to regulate cell differentiation in other eukaryotes. To determine whether lncRNAs are also involved in parasite differentiation, we used RNA sequencing to survey the T. brucei genome, identifying 1428 previously uncharacterized lncRNA genes. We find that grumpy lncRNA is a key regulator that promotes parasite differentiation into the quiescent stumpy form. This function is promoted by a small nucleolar RNA encoded within the grumpy lncRNA. snoGRUMPY binds to messenger RNAs of at least two stumpy regulatory genes, promoting their expression. grumpy overexpression reduces parasitemia in infected mice. Our analyses suggest that T. brucei lncRNAs modulate parasite-host interactions and provide a mechanism by which grumpy regulates cell differentiation in trypanosomes.

Identification and Semi-quantification of Protozoa from the Digestive System Microbiota of the Lobster Cockroach Nauphoeta cinerea Oliver, 1789 (Insecta:Blattaria).

INTRODUCTION: The lobster cockroach Nauphoeta cinerea (N. cinerea) is indicated as a promising non-mammalian model, because it presents behavioral and biochemical alterations also observed in conventional models. In this research, we identified and characterized the distribution of protozoa that inhabit the digestive system (DS) of N. cinerea cockroaches. METHODS: The adult specimens of N. cinerea used in this study (n = 32) were obtained at the Federal University of Santa Maria, dissected and had their visceral contents observed in bright-field microscopy without staining and after application of lugol, Ziehl-Neelsen staining, EA36 trichrome and simulated dark-field microscopy with application of nankin ink. The presence of protozoa in different portions of the DS was semi-quantified by a system of crosses (+). RESULTS: The main taxa observed were: amoebas (Archaemebae:Entamoebida), gregarins (Apicomplexa:Eugregarinide), coccidia (Apicomplexa:Eucoccidiorida), kinetoplastids (Kinetoplastea:Kinetoplastida) and oxymonads (Preaxostyla:Oxymonadida). The highest prevalence of amoebas and gregarines was observed in the medial portion of the DS, while for the other groups, this was seen in the final portion, and in the case of coccidia, such prevalence was specially evidenced by the alcohol-acid coloration. In the present work, the great biological diversity that exists in the microbiota of the digestive system of Nauphoeta cinerea was demonstrated, being possible to find several pathogenic species for humans such as Entamoeba histolytica/dispar/moshkovskii, Cryptosporidium sp. and Cyclospora cayetanensis. There is still a lot to know about the interactions between endocommensal protozoa and their respective invertebrate hosts, so the best way to clarify such relationships is through molecular and genetic test.

Evaluation of anaesthetic depth and cardiopulmonary effects of propofol infusion rate in Sapajus apella previously chemically contained with dextroketamine-midazolam.

BACKGROUND: This study evaluated the cardiopulmonary effects and anaesthetic depth induced by a propofol infusion rate of 0.8 mg/kg/min in monkeys (Sapajus apella). MATERIALS AND METHODS: Five capuchin monkeys received dextroketamine-midazolam intramuscularly. After a maximum duration of 5 min, the values of the physiological parameters were recorded, and a venous catheter was placed. After recovery from chemical restraint, the animals were anaesthetized with propofol intravenously, which was maintained for 1 h. Physiological parameters, anaesthetic depth, the time and quality of anaesthetic recovery were evaluated. RESULTS: Heart and respiratory rates, systolic blood pressure and rectal temperature during propofol infusion were lower than those during anaesthesia induction with dextroketamine-midazolam. Unconsciousness, muscle relaxation and lack of response to tail clamping were observed during propofol infusion. No animals showed excitement or vocalization during anaesthetic recovery. CONCLUSION: Propofol infusion rate of 0.8 mg/kg/min promoted surgical general anaesthesia, with transient hypotension, which showed excellent anaesthetic recovery.

Hematological reference values and animal welfare parameters of BALB/C-FMABC (Mus musculus) inoculated with Ehrlich tumor kept in the vivarium at ABC Medical School.

BACKGROUND: Biochemical and hematological parameters are important tools for assessing the physiological profile of vital organs, and can be recorded to create reference values used for clinical diagnosis of diseases. Many research laboratories lack the means to establish their own set of reference parameters for use in their research, and while there are articles in the literature that discuss laboratory parameters for healthy BALB/c mice, few studies address the evaluation of these parameters in pathological situations, such as in mice inoculated with Ehrlich tumor. METHOD: BALB/c-FMABC mice previously inoculated with Ehrlich tumor were maintained under appropriate conditions. Blood samples were taken for analysis of hematological parameters using automated and semi-automated equipment to create a set of the animal welfare parameters for evaluation. RESULT: Results were obtained for all the hematological parameters for all groups analyzed. These showed: statistically significant differences between the initial and final tumor weight; comparable initial tumour volume and weight; an increase in leukocytes in the 7-day group with a characteristic predominance of lymphocytes and neutrophils; statistically significant changes in RDW in the 21-day group and in the welfare parameters in the 28-day group. CONCLUSION: The study successfully defined and established reference values for hematological and welfare parameters for all groups analyzed.

Interference of blood storage containing K2EDTA and K3EDTA anticoagulants in the automated analysis of the hemogram / Interferência da estocagem de sangue contendo os anticoagulantes K2EDTA e K3EDTA na análise automatizada do hemograma

ABSTRACT Introduction: The present work evaluated the possible alterations in different hemogram parameters as: total erythrocyte count, hematocrit, leukocyte, and platelet count, against different times of sample storage at refrigerated and room temperature towards the effects of anticoagulants that can affect the variation of laboratory results. Objective: Compare variations in automated hemogram analysis, with blood collected in tubes containing dipotassium ethylenediaminetetraacetic acid (K2EDTA) and tripotassium ethylenediaminetetraacetic acid (K3EDTA). Material and methods: A comparative study was carried out on differential leukocyte count and absolute leukocyte count, hemoglobin determination and red blood cell count and platelet count. Therefore, it researches the anticoagulant that brings less interferences in hemogram analysis according to storage, at temperatures from 2°C to 8°C and 25°C (room temperature), and the time window between collection and analysis (4, 6, and 8 hours). These determinations were carried out after homogenization from five to eight inversions using the automated device Sysmex XN-1000TM. Eighteen biological samples of venous blood were collected, used as control, from patients aged 18 and over that did not have any hematologic disease. Results: The results were evaluated through descriptive statistical analysis, and comparison of mean values through the analysis of variance (Anova). In accordance with the results presented, there were not changes in the parameters by refrigerating the sample in the period of 8 hours, except for the platelet count, presenting oscillations when stored under refrigeration from 2°C to 8°C. Conclusion: At room temperature, the parameters mean corpuscular volume (MCV), mean corpuscular hemoglobin concentration (MCHC), and hematocrit presented significant statistical differences.

RESUMEN Introducción: Este trabajo evaluó los posibles cambios en diferentes parámetros del hemograma, como conteo de eritrocitos totales, leucocitos, hematocrito y plaquetas, con respecto a diferentes tiempos de almacenamiento de la muestra en ambiente refrigerado y temperatura ambiente en cuanto a los efectos de los anticoagulantes, que pueden afectar los resultados del análisis de laboratorio. Objetivo: Comparar los cambios presentes en el análisis del hemograma automatizado, recogido en tubos que contienen ácido etilendiaminotetraacético dipotásico (K2EDTA) y tripotásico (K3EDTA). Material y método: Estudio comparativo realizado para conteo diferencial/absoluto de leucocitos, determinación de hemoglobina y conteo de eritrocitos y plaquetas, a fin de investigar el anticoagulante que trae menos interferencia en el análisis del hemograma según su almacenamiento - temperatura de 2°C a 8°C y 25°C (temperatura ambiente) y ventana de tiempo entre recuento y análisis de 4, 6, y 8 horas. Se realizaron las determinaciones luego de homogeneizar las muestras con cinco a ocho inversiones en el analizador automatizado Sysmex XN-1000TM. Dieciocho muestras de sangre venosa de pacientes mayores de 18 años, sin enfermedades hematológicas, fueron recogidas y usadas como control. Resultados: Se evaluaron los resultados mediante un análisis descriptivo, con comparación de medias por análisis de la varianza (Anova). De acuerdo con los resultados, no hubo cambios en los parámetros enfriándose la muestra en el período de 8 horas, a excepción del recuento de plaquetas, que presentó oscilaciones bajo refrigeración (2°C-8°C). Conclusión: A temperatura ambiente, los parámetros volumen corpuscular medio (VCM), concentración de hemoglobina corpuscular media (CHCM) y hematocrito presentan diferencia estadísticamente significativa.

RESUMO Introdução: O presente trabalho avaliou as possíveis alterações em diferentes parâmetros do hemograma, como contagem de eritrócitos totais, leucócitos, hematócrito e plaquetas, em relação a diferentes tempos de armazenamento da amostra em ambiente refrigerado e em temperatura ambiente quanto aos efeitos dos anticoagulantes, que podem afetar a variabilidade de seus resultados laboratoriais. Objetivo: Comparar as variações presentes na análise do hemograma automatizado, colhido nos tubos contendo ácido etilenodiamino tetra-acético dipotássico (K2EDTA) e tripotássico (K3EDTA). Material e métodos: Estudo comparativo realizado para contagem diferencial/absoluta dos leucócitos, determinação de hemoglobina e contagem de hemácias e plaquetas, com o intuito de investigar o anticoagulante que traz menos interferentes na análise do hemograma de acordo com sua estocagem - temperatura de 2°C a 8°C e 25°C (temperatura ambiente) e janela de tempo entre a coleta e a análise de 4, 6 e 8 horas. Essas determinações foram realizadas após homogeneização de cinco a oito inversões pelo aparelho automatizado Sysmex XN-1000TM. Dezoito amostras biológicas de sangue venoso de pacientes com idade superior a 18 anos, sem doenças hematológicas, foram coletadas e utilizadas como controle. Resultados: Os resultados foram avaliados por meio de uma análise estatística descritiva, com comparação de médias através da análise de variância (Anova). De acordo com os resultados apresentados, não ocorreram alterações nos parâmetros ao refrigerar a amostra no período de 8 horas, com exceção da contagem de plaquetas, que apresentou oscilações quando armazenadas sob refrigeração de 2°C a 8°C. Conclusão: Na temperatura ambiente, os parâmetros volume corpuscular médio (VCM), concentração de hemoglobina corpuscular média (CHCM) e hematócrito apresentaram diferença estatística significante.

Myocardial Perfusion by Coronary Computed Tomography in the Evaluation of Myocardial Ischemia: Simultaneous Stress Protocol with SPECT / Perfusão Miocárdica por Angiotomografia de Coronárias na Avaliação da Isquemia Miocárdica: Protocolo de Estresse Simultâneo com SPECT

Abstract Background: Functional assessment to rule out myocardial ischemia using coronary computed tomography angiography (CCTA) is extremely important and data on the Brazilian population are still limited. Objective: To assess the diagnostic performance of myocardial perfusion by CCTA in the detection of severe obstructive coronary artery disease (CAD) compared with single-photon emission computerized tomography (SPECT). To analyze the importance of anatomical knowledge to understand the presence of myocardial perfusion defects on SPECT imaging that is not identified on computed tomography (CT) scan. Method: A total of 35 patients were evaluated by a simultaneous pharmacologic stress protocol. Fisher's exact test was used to compare proportions. The patients were grouped according to the presence or absence of significant CAD. The area under the ROC curve was used to identify the diagnostic performance of CCTA and SPECT in perfusion assessment. P < 0.05 values were considered statistically significant. Results: For detection of obstructive CAD, CT myocardial perfusion analysis yielded an area under the ROC curve of 0.84 [a 95% confidence interval (CI95%): 0.67-0.94, p < 0.001]. SPECT myocardial perfusion imaging, on the other hand, showed an AUC of 0.58 (95% CI 0.40 - 0.74, p < 0.001). In this study, false-positive results with SPECT are described. Conclusion: Myocardial perfusion analysis by CTA displays satisfactory results compared to SPECT in the detection of obstructive CAD. CCTA can rule out false-positive results of SPECT.

Resumo Fundamento: A avaliação funcional para descartar a isquemia miocárdica utilizando a angiotomografia computadorizada (angio-TC) de coronárias é de extrema importância e dados na população brasileira ainda são escassos. Objetivo: Avaliar o desempenho diagnóstico da perfusão miocárdica pela angio-TC de coronárias na detecção de doença arterial coronariana (DAC) obstrutiva significativa em comparação com a tomografia computadorizada por emissão de fóton único (SPECT; do inglês, single photon emission computerized tomography). Analisar a importância do conhecimento anatômico para entender a presença de defeito de perfusão miocárdica pela SPECT que não é identificado pela tomografia computadorizada (TC). Método: Trinta e cinco pacientes foram avaliados por um protocolo de estresse farmacológico simultâneo. O teste exato de Fisher foi utilizado para comparação entre as proporções. Os pacientes foram agrupados de acordo com a presença ou não de DAC significativa. A área sob a curva foi utilizada para identificar o desempenho diagnóstico da avaliação da perfusão pela angio-TC de coronárias e pela SPECT. Os valores de p < 0,05 foram considerados estatisticamente significativos. Resultados: Para detecção de DAC obstrutiva a avaliação da perfusão miocárdica pela TC teve uma área sob a curva de 0,84 [intervalo de confiança de 95% (IC95%): 0,67 a 0,94, p < 0,001]. Já o estudo da perfusão miocárdica pela SPECT foi de 0,58 (IC95%: 0,40 a 0,74, p < 0,001). Neste estudo, foram descritos falso-positivos pela SPECT. Conclusão: A avaliação da perfusão miocárdica pela angio-TC apresenta resultados satisfatórios em comparação com os da SPECT na detecção de DAC obstrutiva. A angio-TC de coronárias tem capacidade de afastar falso-positivos da SPECT.

Myocardial Perfusion by Coronary Computed Tomography in the Evaluation of Myocardial Ischemia: Simultaneous Stress Protocol with SPECT.

BACKGROUND: Functional assessment to rule out myocardial ischemia using coronary computed tomography angiography (CCTA) is extremely important and data on the Brazilian population are still limited. OBJECTIVE: To assess the diagnostic performance of myocardial perfusion by CCTA in the detection of severe obstructive coronary artery disease (CAD) compared with single-photon emission computerized tomography (SPECT). To analyze the importance of anatomical knowledge to understand the presence of myocardial perfusion defects on SPECT imaging that is not identified on computed tomography (CT) scan. METHOD: A total of 35 patients were evaluated by a simultaneous pharmacologic stress protocol. Fisher's exact test was used to compare proportions. The patients were grouped according to the presence or absence of significant CAD. The area under the ROC curve was used to identify the diagnostic performance of CCTA and SPECT in perfusion assessment. P < 0.05 values were considered statistically significant. RESULTS: For detection of obstructive CAD, CT myocardial perfusion analysis yielded an area under the ROC curve of 0.84 [a 95% confidence interval (CI95%): 0.67-0.94, p < 0.001]. SPECT myocardial perfusion imaging, on the other hand, showed an AUC of 0.58 (95% CI 0.40 - 0.74, p < 0.001). In this study, false-positive results with SPECT are described. CONCLUSION: Myocardial perfusion analysis by CTA displays satisfactory results compared to SPECT in the detection of obstructive CAD. CCTA can rule out false-positive results of SPECT.

γδ-T cells promote IFN-γ-dependent Plasmodium pathogenesis upon liver-stage infection.

Cerebral malaria (CM) is a major cause of death due to Plasmodium infection. Both parasite and host factors contribute to the onset of CM, but the precise cellular and molecular mechanisms that contribute to its pathogenesis remain poorly characterized. Unlike conventional αß-T cells, previous studies on murine γδ-T cells failed to identify a nonredundant role for this T cell subset in experimental cerebral malaria (ECM). Here we show that mice lacking γδ-T cells are resistant to ECM when infected with Plasmodium berghei ANKA sporozoites, the liver-infective form of the parasite and the natural route of infection, in contrast with their susceptible phenotype if challenged with P. berghei ANKA-infected red blood cells that bypass the liver stage of infection. Strikingly, the presence of γδ-T cells enhanced the expression of Plasmodium immunogenic factors and exacerbated subsequent systemic and brain-infiltrating inflammatory αß-T cell responses. These phenomena were dependent on the proinflammatory cytokine IFN-γ, which was required during liver stage for modulation of the parasite transcriptome, as well as for downstream immune-mediated pathology. Our work reveals an unanticipated critical role of γδ-T cells in the development of ECM upon Plasmodium liver-stage infection.

Cardiac magnetic resonance and amyloidosis: review / Ressonância magnética cardíaca e amiloidose: revisão

Amyloidosis is a disease caused by extracellular deposition of insoluble protein fibrils, that results in changes in tissue architecture and consequently modification of the organ structure. Cardiac involvement is common in amyloidosis. Two major types of systemic amyloidosis affect the myocardium ­ immunoglobulin light chain and transthyretin amyloidosis ­ each leading to different prognosis. Early detection and diagnosis of cardiac amyloidosis are the main objectives in the assessment of the disease. New techniques of magnetic resonance imaging have minimized the need for biopsies for the diagnosis. Late gadolinium enhancement technique, and more recently T1 mapping, have allowed a simplified evaluation of amyloid deposits and extracellular volume. The aim of this review was to describe basic concepts and updates of the use of magnetic resonance imaging for the diagnosis amyloidosis and evaluation of its severity

Purpuriocillium lilacinum infection in captive loggerhead sea turtle hatchlings.

This paper reports a case of Purpureocillium lilacinum infection in seven loggerhead sea turtle (Caretta caretta) hatchlings kept in an aquarium under inadequate condition. The fungus was isolated from skin and pulmonary lesions. Metilene blue and NaCl solutions, Schinus terebinthifolius and eucalyptus essential oils Minimum Inhibitory Concentrations were determined indicating new possibilities for treatment.

Therapeutic Doses of Eltrombopag do not Inhibit Hepatic BCRP in Healthy Volunteers: Intravenous Ceftriaxone as a Model.

PURPOSE: Ceftriaxone elimination occurs through breast cancer resistance transporter (BCRP) and multidrug resistance-associated protein 2 (MRP-2) which are expressed on the canalicular membrane of hepatocytes. Eltrombopag, a thrombopoetin receptor agonist used in the treatment of immune thrombocytopenic purpura, is reported in in vitro studies as an inhibitor of intestinal BCRP but not an inhibitor of hepatic BCRP. Thus, the present study evaluates the effect of therapeutic doses of eltrombopag on the clinical pharmacokinetics of intravenous ceftriaxone. METHODS: Healthy adult (n=12) were treated with oral doses of eltrombopag (0, 25 or 50 mg) 28 and 4 h prior to intravenous ceftriaxone administration (1g). Serial blood samples were collected up to 48 h after ceftriaxone administration and plasma samples were analysed by LC-MS/MS using 50 µL aliquots (total concentration) and 100 µL (unbound concentration). RESULTS: A method to analyze total and unbound ceftriaxone in plasma using LC-MS/MS was developed and validated with linearity from 1 to 200 µg/mL. Both methods are sensitive, precise and accurate with coefficients of variation less than 15% in the study of inter- and intra-assay precision and accuracy. Ceftriaxone pharmacokinetics in healthy adults were described using a bicompartmental model, with a mean clearance of 0.96 L/h (CI95% 0.71-1.20) and AUC0-∞of 1106 mg.h/mL (CI95% 811-1400) for volunteers that received only ceftriaxone; clearance of 0.95 L/h (CI95% 0.77-1.13) and AUC0-∞ of 1083 mg.h/mL (CI95% 876-1290) for volunteers that received ceftriaxone plus 25 mg of eltrombopag and clearance of 0.96 L/h (CI95% 0.74-1.19) and AUC0-∞ of 1072 mg.h/mL (CI95% 872-1273) for volunteers that received ceftriaxone plus 50 mg of eltrombopag. CONCLUSIONS: The results do not support the existence of a clinical pharmacokinetic drug interaction involving hepatic BCRP in human subjects receiving intravenous ceftriaxone and oral eltrombopag. This article is open to POST-PUBLICATION REVIEW. Registered readers (see "For Readers") may comment by clicking on ABSTRACT on the issue's contents page.

Effect of CYP2D6 Poor Metabolizer Phenotype on Stereoselective Nebivolol Pharmacokinetics.

BACKGROUND: Nebivolol is a drug available as a racemate of d-nebivolol (SRRR) and lnebivolol (RSSS). In human liver microsomes, CYP2D6 mainly catalyses the metabolism of lnebivolol, while CYP2C19 catalyses the metabolism of d-nebivolol. Nebivolol stereoselective pharmacokinetics has been described only for extensive metabolizers (EM). OBJECTIVE: To describe the stereoseletive nebivolol pharmacokinetics in CYP2D6 poor metabolizers (PM) and to assess whether the phenotype has an impact on nebivolol pharmacokinetics. METHODS: Three healthy volunteers PM phenotyped (ratios of 20.1, 220 and 244 for the 8 h urinary excretion of metoprolol/alfa-hydroxymetoprolol) received a single oral dose of racemic nebivolol and sequential blood samples were collected between zero (predose) and 48 h. RESULTS: The obtained data were compared to 22 EM subjects with normal kidney function enrolled in our previous study. For both isomers, Cmax, Tmax and AUC0-48 were significantly greater in the PM group compared to the EMs (p = 0.006 - 0.001). For d-nebivolol, Cmax, Tmax and AUC0-48 were, on average, 5.9, 2.7 and 15.0 larger in PMs. The corresponding values for l-nebivolol were 4.4, 2.7 and 17.5. CONCLUSION: The decline in plasma concentration of both nebivolol isomers in PM phenotypes, especially those with MR of 220 and 244, which indicate minimal or absent CYP2D6 activity, points to alternative mechanisms for nebivolol elimination. Collectively, our results are the first to show the significant impact of CYP2D6 PM phenotype on the metabolic disposition and in vivo exposure to both nebivolol isomers.

Distribution of species and antimicrobial resistance among enterococci isolated from the fecal microbiota of captive blue-fronted parrot (Amazona aestiva) in Rio de Janeiro, Brazil.

Enterococcal strains recovered from fecal samples of captive blue-fronted parrots (Amazona aestiva) assisted at two wild animal screening centers in Rio de Janeiro, Brazil, were identified as Enterococcus hirae (the predominant species; 75.3%), followed by Enterococcus faecalis (17.3%), Enterococcus casseliflavus (4.8%), Enterococcus gallinarum (1.7%), and Enterococcus hermanniensis (0.9%). All strains were susceptible to linezolid and teicoplanin. Rates of nonsusceptibility (including resistant and intermediate categories) to other 16 antimicrobials tested varied from 69.3% to 0.4%, A considerable proportion (48.0%) of the strains was multidrug-resistant and diverse genetic determinants associated with antimicrobial resistance were identified. Tetracycline-resistant strains carried the tet(M) and/or tet(L) genes. Macrolides resistance was associated with the erm(B), erm(A) and mefA genes, while 43.2% of the isolates were negative for the investigated genes. High-level resistance to gentamicin associated with the aac(6')-le-aph(2″)-la gene was detected in one E. faecalis strain. The two strains presenting high-level resistance to streptomycin were negative for the ant(6')-Ia, ant(3')-Ia, ant(9')-Ia and ant(9')-Ib genes. The vat(D) gene was found in all the 47 quinupristin/dalfopristin resistant strains identified as non-E. faecalis. Analysis of PFGE profiles of E. hirae strains after restriction with SmaI demonstrated the occurrence of five clonal groups. The predominant E. hirae clone was distributed among birds in the two institutions, suggesting that this clone was well adapted to the host and environments investigated. The four clonal groups identified among E. faecalis were composed by small numbers of strains and, generally, restricted to birds in the same sector. The occurrence of enterococcal strains exhibiting antimicrobial resistance traits and carrying genetic determinants that represent potential threats to the health of both humans and animals, in the intestinal microbiota of A. aestiva, highlights the need for additional monitoring studies to elucidate the population structure and the dynamics of transmission of these microorganisms among animals, humans and the environment.