Emergence of clonal complex 5 (CC5) methicillin-resistant Staphylococcus aureus (MRSA) isolates susceptible to trimethoprim-sulfamethoxazole in a Brazilian hospital

In this study, genotyping techniques including staphylococcal chromosomal cassette mec (SCCmec) typing, pulsed-field gel electrophoresis (PFGE), multilocus sequence typing (MLST) and restriction-modification tests were used to compare the molecular characteristics of methicillin-resistant Staphylococcus aureus (MRSA) isolates recovered at two times within a 10-year interval (1998 and 2008) from a tertiary Brazilian hospital. In addition, the antimicrobial susceptibility profiles were analyzed. All 48 MRSA isolates from 1998 and 85.7% from 2008 (48/56 isolates) displayed multidrug-resistance phenotypes and SCCmec III. All but one of the 13 representative SCCmec III isolates belonged to CC8 and had PFGE patterns similar to that of the BMB9393 strain (Brazilian epidemic clone of MRSA; BEC). In 2008, we found an increased susceptibility to rifampicin and chloramphenicol among the SCCmec III isolates. In addition, we detected the entrance of diverse international MRSA lineages susceptible to trimethoprim-sulfamethoxazole (SXT), almost all belonging to CC5. These non-SCCmec III isolates were related to the USA 300 (ST8-SCCmec IV; PFGE-type B), USA 800 (ST5-SCCmec IV; subtype D1), USA 100 (ST5-SCCmec II; subtype D2), and EMRSA-3/Cordobes (ST5-SCCmec I, type C) clones. To the best of our knowledge, this is the first report of the emergence of isolates genetically related to the EMRSA-3/Cordobes clone in southeast Brazil. In this regard, these isolates were the most common non-SCCmec III MRSA in our institution, accounting for 8.9% of all isolates recovered in 2008. Thus, despite the supremacy of BEC isolates in our country, significant changes may occur in local MRSA epidemiology, with possible consequences for the rationality of MRSA empiric therapy.

Identificação botânica e química de espécies vegetais de uso popular no Rio Grande do Norte, Brasil / Botanical and chemical identification of plant species of popular use in Rio Grande do Norte, Brazil

Plantas medicinais são utilizadas mundialmente como uma das principais formas de cuidado primário de saúde. No entanto, a literatura indica que muitas espécies podem apresentar composição química variável, toxicidade ou difícil identificação. O objetivo do presente estudo foi obter critérios úteis para o controle de qualidade farmacognóstico das principais espécies vegetais de uso popular no estado do Rio Grande do Norte, utilizando metodologias de análise botânica (morfodiagnose macro e microscópica) e química (triagem fitoquímica e cromatografia em camada delgada), evitando assim adulterações ou uso inadequado dessas plantas medicinais no estado. No total, sete espécies foram analisadas Acmella oleracea, Chenopodium ambrosioides, Lippia alba, Mentha piperita, Ocimum gratissimum, Peumus boldus e Rosmarinus officinalis. Diversos marcadores botânicos e fitoquímicos foram identificados, contribuindo dessa forma para a correta identificação destas espécies de plantas medicinais importantes no estado do Rio Grande do Norte.

Medicinal plants are worldwide used as one of the main forms of primary healthcare. However, the literature indicates that many species may have variable chemical composition, toxicity, or even difficult identification. The aim of this study was to obtain useful criteria for pharmacognostic quality control of the main plant species of popular use in the state of Rio Grande do Norte, using methods of botanical (macro and microscopic morphodiagnosis) and chemical (phytochemical screening and thin-layer chromatography) analysis, thus preventing adulteration or inappropriate use of these medicinal plants in the state. In total, seven species were analyzed Acmella oleracea, Chenopodium ambrosioides, Lippia alba, Mentha piperita, Ocimum gratissimum, Peumus boldus and Rosmarinus officinalis. Several botanical and phytochemical markers were identified, thereby contributing to the correct identification of these important medicinal plant species in the state of Rio Grande do Norte.

Genotyping of methicillin-resistant Staphylococcus aureus isolates obtained in the Northeast region of Brazil

Methicillin-resistant Staphylococcus aureus (MRSA) is a major agent of hospital infections worldwide. In Brazil, a multiresistant MRSA lineage (ST239-SCCmecIIIA), the so-called Brazilian epidemic clone (BEC), has predominated in all regions. However, an increase in nosocomial infections caused by non-multiresistant MRSA clones has recently been observed. In the present study, 45 clinical isolates of MRSA obtained from a university hospital located in Natal city, Brazil, were identified by standard laboratory methods and molecularly characterized using staphylococcal chromosome cassette mec (SCCmec) typing and pulsed-field gel electrophoresis. Antimicrobial susceptibility testing was carried out using CLSI methods. The MRSA isolates studied displayed a total of 8 different pulsed-field gel electrophoresis patterns (types A to H) with predominance (73 percent) of pattern A (BEC-related). However, MRSA harboring SCCmec type IV were also identified, 3 (7 percent) of which were genetically related to the pediatric clone - USA800 (ST5-SCCmecIV). In addition, we found a considerable genetic diversity within BEC isolates. MRSA displaying SCCmecIV are frequently susceptible to the majority of non-β-lactam antibiotics. However, emergence of multiresistant variants of USA800 was detected.

The first report in Brazil of severe infection caused by community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA)

Community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) is an emergent pathogen in Brazil. However, there are no data on the prevalence of CA-MRSA. We report here the first well-characterized case of severe life-threatening CA-MRSA infection in a child living in Rio de Janeiro city. The patient had many complications including hematogenous osteomyelitis and involvement of multiple sites requiring drainage of soft-tissue abscess, and pleural and pericardial empyema. The MRSA isolates recovered were genotyped using PFGE, SCCmec typing and multilocus sequence typing. Disk diffusion tests were performed following Clinical and Laboratory Standards Institute recommendations. In addition, the presence of Panton-Valentine leukocidin (PVL) was assessed by PCR amplification, using specific primers for lukF-pv (encoding for the F subunit of the PVL). The bacterial isolates were related to the ST30-SCCmecIV lineage (Oceania Southwest Pacific clone), a PVL producer CA-MRSA previously detected in Porto Alegre, RS, Brazil. Also, the isolates analyzed were susceptible to all non-â-lactam antibiotics tested. The present report demonstrates that disseminated CA-MRSA disease is also occurring in Rio de Janeiro. Thus, the empirical treatment of moderate or severe infections suspected of being associated with CA-MRSA needs to be reviewed in order to allow prompt initiation of an effective therapy that also covers these microorganisms.

Changes in the biogenic amine content of the prefrontal cortex, amygdala, dorsal hippocampus, and nucleus accumbens of rats submitted to single and repeated sessions of the elevated plus-maze test

It has been demonstrated that exposure to a variety of stressful experiences enhances fearful reactions when behavior is tested in current animal models of anxiety. Until now, no study has examined the neurochemical changes during the test and retest sessions of rats submitted to the elevated plus maze (EPM). The present study uses a new approach (HPLC) by looking at the changes in dopamine and serotonin levels in the prefrontal cortex, amygdala, dorsal hippocampus, and nucleus accumbens in animals upon single or double exposure to the EPM (one-trial tolerance). The study involved two experiments: i) saline or midazolam (0.5 mg/kg) before the first trial, and ii) saline or midazolam before the second trial. For the biochemical analysis a control group injected with saline and not tested in the EPM was included. Stressful stimuli in the EPM were able to elicit one-trial tolerance to midazolam on re-exposure (61.01 percent). Significant decreases in serotonin contents occurred in the prefrontal cortex (38.74 percent), amygdala (78.96 percent), dorsal hippocampus (70.33 percent), and nucleus accumbens (73.58 percent) of the animals tested in the EPM (P < 0.05 in all cases in relation to controls not exposed to the EPM). A significant decrease in dopamine content was also observed in the amygdala (54.74 percent, P < 0.05). These changes were maintained across trials. There was no change in the turnover rates of these monoamines. We suggest that exposure to the EPM causes reduced monoaminergic neurotransmission activity in limbic structures, which appears to underlie the "one-trial tolerance" phenomenon.

Avaliações da relação fósforo: flúor em suplementos minerais para bovinos comercializados na região nordeste do Paraná / Relation phosphorus: fluorine evaluations in mineral supplements for cattle commercialized in the northeast of the State of Paraná / Avaluaciones de la relación fosforo: fluor encontrados en suplementos minerales para vacunos, comercializados en la región noreste del estado de Paraná

Foram quantificados os teores de fósforo (P) e flúor (F) em doze diferentes amostras de suplementos minerais para bovinos, mais comercializados na região Nordeste do Estado do Paraná. Para a determinação do fósforo foi utilizado espectrofotômetro de colorimetria com região UV visível e, para a determinação do flúor, utilizou-se eletrodo de íon específico para o elemento e potenciômetro com escala em milivolts. Os resultados mostraram altos teores de flúor em duas amostras, e diferentes alterações na relação P:F, com variadas concentrações dos elementos, principalmente do fósforo, possibilitando a conclusão de que quase todas as formulações caracterizaram-se como incorretas pelas informações prestadas nos rótulos dos fabricantes e, irregulares na relação P:F calculada, quando comparada aos limites estabelecidos pela normatização em vigor no País.

We quantifi ed the contents of phosphorus (P) and fl uorine (F) in twelve mineral brands of supplements for cattle, more commercialized in the region northeast of the state of Paraná. For the phosphorus's determination was utilized spectrofotometry and for fl uorine was utilized equipment with specifi c ion and scale in milivolts. The results showed high contents of fl uorine in two samples, and alterations in the relation P: F, with varied concentrations of both elements, mainly of the phosphorus. The authors concluded that almost all formulations were incorrect according to the information from the manufactures' labels and, irregular in the relation P: F calculated, when compared to the limits established by Brazilian Government rules.

Fueron cuantifi cadas las concentraciones de Fósforo (P) y Fluor (f) en doce diferentes muestras de Suplementos Minerales para vacunos, entre los mas comercializados en la región noreste del Estado del Paraná. Para la determinación del Fosforo, fue utilizado un Espectofotómetro de Colormetria con región UV visible, y para la determinación del Fluor un electrodo de Ion Específi co para este elemento, aliado a un Potenciometro con lectura de variables en Milivolts. Los resultados mostraron altos porcentajes de Fluor en dos de las muestras, y en las otras, variadas alteraciones en la relación P:F, con diferentes concentraciones de estos elementos, principalmente del Fosforo. Esto posibilita la conclusión de que casi todas las formulaciones se caracterizaron como incorrectas por las informaciones que son apresentadas en las etiquetas de los fabricantes, ademas de irregulares na relación P:F calculada, en comparación con los límites establecidos por las Normas vigentes en el Brazil.

Modulation of fibronectin expression in the central nervous system of Lewis rats with experimental autoimmune encephalomyelitis

Fibronectin (FN), a large family of plasma and extracellular matrix (ECM) glycoproteins, plays an important role in leukocyte migration. In normal central nervous system (CNS), a fine and delicate mesh of FN is virtually restricted to the basal membrane of cerebral blood vessels and to the glial limitans externa. Experimental autoimmune encephalomyelitis (EAE), an inflammatory CNS demyelinating disease, was induced in Lewis rats with a spinal cord homogenate. During the preclinical phase and the onset of the disease, marked immunolabelling was observed on the endothelial luminal surface and basal lamina of spinal cord and brainstem microvasculature. In the paralytic phase, a discrete labelling was evident in blood vessels of spinal cord and brainstem associated or not with an inflammatory infiltrate. Conversely, intense immunolabelling was present in cerebral and cerebellar blood vessels, which were still free from inflammatory cuffs. Shortly after clinical recovery minimal labelling was observed in a few blood vessels. Brainstem and spinal cord returned to normal, but numerous inflammatory foci and demyelination were still evident near the ventricle walls, in the cerebral cortex and in the cerebellum. Intense expression of FN in brain vessels ascending from the spinal cord towards the encephalon preceded the appearance of inflammatory cells but faded away after the establishment of the inflammatory cuff. These results indicate an important role for FN in the pathogenesis of CNS inflammatory demyelinating events occurring during EAE