Introdução: Pneumonia hospitalar é a mais fatal das infecções hospitalares, com taxas de mortalidade de 30 a 60%. Estima-se que 15% de todas as mortes associadas à hospitalização estejam diretamente ...relacionadas a pneumonias hospitalares. O SENTRY é um estudo de vigilância de resistência a antimicrobianos envolvendo centros médicos em todo o mundo. Objetivo: Avaliar a sensibilidade a antimicrobianos de bactérias isoladas no trato respiratório baixo de pacientes com pneumonia internados em hospitais brasileiros. Material e métodos: Foram avaliadas 525 amostras bacterianas de 11 hospitais brasileiros, como parte do programa SENTRY. Os isolados foram testados por microdiluição em caldo contra um grande número de antimicrobianos. Resultados: As cinco espécies mais freqüentes foram (n/%): Pseudomonas aeruginosa (158/30,1%), Staphylococcus aureus (103/19,6%), Acinetobacter spp. (68/13,0%), Klebsiella spp. (50/9,5%), e Enterobacter spp. (44/8,4%). Essas cinco espécies representam mais de 80% de toda a amostragem. A P. aeruginosa apresentou altas taxas de resistência à maioria dos antimicrobianos testados. As maiores taxas de sensibilidade foram apresentadas por piperacilina/tazobactam (71,5%) e meropenem (69,0%). Os compostos com maior atividade in vitro contra Acinetobacter spp. foram imipenem e meropenem (80,9% de sensibilidade) seguido pela tetraciclina (63,2%). A sensibilidade das amostras de Klebsiella spp. foi muito baixa. MICs > ou = 2mig/mL para ceftriaxona ou ceftazidima, indicando produção de ESBL, foram encontrados em 36,0% das amostras. Os antimicrobianos mais ativos contra Klebsiella spp. foram os carbapenens (100% de sensibilidade) e as quinolonas (92,0% de sensibilidade). Ceftriaxona foi ativa contra somente 56,8% das amostras de Enterobacter spp. (MIC50, 1mig/mL), enquanto a cefepima foi ativa contra 88,6% destes isolados (MIC50, <= 0,12mig/mL). A resistência à oxacilina foi detectada em 43,7% dos isolados de S. aureus. As drogas mais ativas contra essa espécie foram: vancomicina, teicoplanina, quinupristin-dalfopristin e linezolida. Conclusões: Os resultados do presente estudo mostraram alta prevalência de Acinetobacter spp. e altas taxas de resistência entre bacilos gram-negativos quando comparados com resultados de estudos norte-americanos e europeus.
Machado-Joseph's disease is caused by a CAG trinucleotide repeat expansion that is translated into an abnormally long polyglutamine tract in the protein ataxin-3. Except for the polyglutamine region, ...proteins associated with polyglutamine diseases are unrelated, and for all of these diseases aggregates containing these proteins are the major components of the nuclear proteinaceous deposits found in the brain. Aggregates of the expanded proteins display amyloid-like morphological and biophysical properties.
Human ataxin-3 containing a non-pathological number of glutamine residues (14Q), as well as its
Caenorhabditis elegans (1Q) orthologue, showed a high tendency towards self-interaction and aggregation, under near-physiological conditions. In order to understand the discrete steps in the assembly process leading to ataxin-3 oligomerization, we have separated chromatographically high molecular mass oligomers as well as medium mass multimers of non-expanded ataxin-3. We show that: (a) oligomerization occurs independently of the poly(Q)-repeat and it is accompanied by an increase in β-structure; and (b) the first intermediate in the oligomerization pathway is a Josephin domain-mediated dimer of ataxin-3. Furthermore, non-expanded ataxin-3 oligomers are recognized by a specific antibody that targets a conformational epitope present in soluble cytotoxic species found in the fibrillization pathway of expanded polyglutamine proteins and other amyloid-forming proteins. Imaging of the oligomeric forms of the non-pathological protein using electron microscopy reveals globular particles, as well as short chains of such particles that likely mimic the initial stages in the fibrillogenesis pathway occurring in the polyglutamine-expanded protein. Thus, they constitute potential targets for therapeutic approaches in Machado-Joseph's disease, as well as valuable diagnostic markers in disease settings.
Objectives: To analyze the antimicrobial susceptibility of
Acinetobacter spp. isolates collected from Latin American medical centers as part of the SENTRY Antimicrobial Surveillance Program and also ...to evaluate the dissemination of multi-drug resistant
Acinetobacter spp. strains in the region.
Methods: A total of 826 isolates of
Acinetobacter spp. from multiple infection sites were collected from January 1997 to December 2001 in ten medical centers and susceptibility tested to >25 selected agents by broth microdilution. Multi-drug resistant
Acinetobacter spp. isolates were molecular typed.
Results: Resistance rates to carbapenems varied significantly among countries. A continued annual increase occurred in the Argentinean medical centers. In contrast, carbapenem resistance was rare in Chilean centers, and decreased significantly in the Brazilian institutions.
Acinetobacter spp. isolates recovered from lower respiratory tract and bloodstream infections were associated with lower antimicrobial susceptibility rates. Resistance rates to imipenem were higher among isolates collected from intensive care units (13.5%) than among isolates from other units. A major ribogroup pattern (521-1) was detected among eight
Acinetobacter spp. strains isolated from three distinct Latin American countries.
Conclusions: This study found that antimicrobial resistance is still a major issue among
Acinetobacter spp. isolates collected from some Latin American countries. The dissemination of a major bacterial cluster in different regions reinforces the importance of longitudinal surveillance programs, such as SENTRY, as valuable tools for monitoring antimicrobial susceptibility rates and guiding local interventions.
L’encéphalite de Rasmussen (ER), caractérisée par une atteinte corticale inflammatoire chronique et atrophiante, n’est qu’exceptionnellement décrite chez l’adulte.
Nous rapportons le cas d’un patient ...de 41ans, sans antécédent, ayant débuté une épilepsie 3ans auparavant avec des crises partielles simples sensitivo-motrices hémicorporelles droites et phasiques avec manque du mot, et parfois généralisation secondaire. Par la suite, plusieurs états de mal épileptique, partiels et généralisés, ont nécessité une majoration des traitements antiépileptiques. On individualise une lésion fronto-insulaire gauche cortico-sous-corticale hypoT1 et hyperT2 avec atrophie corticale progressive en regard sur les IRM cérébrales itératives. Le TEP scanner cérébral objective un hypométabolisme en regard de la lésion. Des décharges infracliniques frontotemporales gauches subintrantes ont été enregistrées à l’EEG. La ponction lombaire met en évidence 5 éléments lymphocytaires par mm3 et une hyperprotéinorachie à 0,54g/L. Le bilan infectieux et les anticorps antineuronaux dans le sang et le LCR sont négatifs. Il n’y a pas d’argument pour un néoplasie sous-jacent sur le scanner thoraco-abdomino-pelvien ou le TEP scanner corps entier. Enfin, la biopsie de la lésion cérébrale est en faveur d’un infiltrat lymphocytaire T CD3+ et CD8+ prédominant dans la substance grise avec des nodules de neuronophagie.
L’ER est une maladie classiquement infantile. Plusieurs cas de début tardif ont été décrits dans la littérature, avec une présentation clinique différente : déficit neurologique, notamment moteur, moins fréquent et évolution plus lente. L’identification de cette encéphalite auto-immune nous a conduit à initier une corticothérapie et une immunosuppression par mycophénolate mofétil.
L’existence d’une encéphalite focale atrophiante à l’âge adulte responsable d’une épilepsie partielle pharmacorésistante doit faire évoquer le diagnostic, bien que rare, d’ER de début tardif.
The principal aim of this study was to evaluate the genomic diversity among the imipenem-nonsusceptible Acinetobacter spp. (INSA) collected from the Latin American medical centers within the SENTRY ...Antimicrobial Surveillance Program. The INSA isolates were collected from patients with bloodstream infections, who were hospitalized in seven Latin American countries between 1997 and 1999. For epidemiologic comparison, 20 carbapenem-susceptible Acinetobacter spp. (CSA) isolates were collected in the same period of time from the respective medical centers. A total of 23 Acinetobacter spp. isolates exhibiting imipenem MIC values of >/=8 microg/ml were typed by ribotyping, an automated molecular method. The isolates showing an identical ribogroup were also typed by pulsed-field gel electrophoresis (PFGE). The antimicrobial susceptibility to various antimicrobial agents was evaluated using a reference broth microdilution technique. Among the INSA isolates, 13 distinct ribogroups were observed, whereas 16 ribogroups were detected among the CSA. Nearly 57% of the INSA belonged to only four ribogroups. Identical ribogroups and PFGE patterns were observed among INSA and CSA isolates collected from medical centers located in different countries (Brazil and Argentina). Our results showed: (1) a higher genomic variability among the CSA; (2) presence of epidemic clones among INSA isolates encountered in Latin American medical centers; and (3) spread of INSA and CSA epidemic clones between Latin American countries.
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