Luciferase isozymes from the Brazilian Aspisoma lineatum (Lampyridae) firefly: origin of efficient pH-sensitive lantern luciferases from fat body pH-insensitive ancestors.

Firefly luciferases usually emit green-yellow bioluminescence at physiological pH values. However, under acidic conditions, in the presence of heavy metals and, at high temperatures they emit red bioluminescence. To understand the structural origin of bioluminescence colors and pH-sensitivity, about 20 firefly luciferases have been cloned, sequenced and investigated. The proton and metal-binding site responsible for pH- and metal sensitivity in firefly luciferases was shown to involve the residues H310, E311 and E354 in firefly luciferases. However, it is still unclear how and why pH-sensitivity arose and evolved in firefly luciferases. Here, we cloned and characterized two novel luciferase cDNAs from the fat body and lanterns of the Brazilian firefly Aspisoma lineatum. The larval fat body isozyme (AL2) has 545 residues, and displays very slow luminescence kinetics and a pH-insensitive spectrum. The adult lantern isozyme (AL1) has 548 residues, displays flash-like kinetics and pH and metal sensitive bioluminescence spectra, and is at least 10 times catalytically more efficient than AL2. Thermostability and CD studies showed that AL2 is much more stable and rigid than the AL1 isozyme. Multialignment and modelling studies show that the E310Q substitution (E310 in AL2 and Q310 in AL1) may have been critical for the origin of pH-sensitivity in firefly luciferases. The results indicate that the lantern efficient flash-emitting pH-sensitive luciferases arose from less efficient glow-type pH-insensitive luciferases found in the fat body of ancestral larval fireflies by enzyme structure flexibilization and substitution at position 310.

Ineffectiveness of information and access to health services: vulnerability to human papillomavirus.

AIM: To examine situations of vulnerability to human papillomavirus in the social representations of young women. BACKGROUND: Human papillomavirus is one of the most frequent sexually transmitted infections among women and constitutes a serious health problem among youth. This problem is embedded in psychosocial issues that promote situations of vulnerability and affect attitudes and behaviour in relation to prevention. METHODS: Qualitative study based on the theory of social representations, conducted among 64 female students in a high school in the city of Rio de Janeiro, Brazil. The study used personal semi-structured interviews, with a lexical analysis by Alceste 2010 software. FINDINGS: The inefficacy of information on the human papillomavirus pointed out individual and social vulnerabilities, and showed relationships between the difficulty of access and the perception of low quality in public health services, which also promotes institutional vulnerability. DISCUSSION: The representation of vulnerability to human papillomavirus infection is associated, not only with individual behaviours related to sexuality and gender identity but also to social and institutional conditions involving insufficient information and low quality of and ineffective access to public health services. CONCLUSION: Situations of vulnerability of young women to human papillomavirus infection influence ways of thinking and acting, when they generate feelings and behaviours that put them at risk. The social representations provided knowledge about how the participants appropriated consensual and reified universes in relation to vulnerability, influencing care and awareness of prevention. IMPLICATION FOR NURSING AND HEALTH POLICY: Situations of vulnerability, whether individual, social or institutional, warrant the attention of nurses and should be prioritized as public health policy goals to reduce the number of cases of human papillomavirus infection among younger women.

Both serotonergic and noradrenergic systems modulate the development of tolerance to chronic stress in rats with lesions of the serotonergic neurons of the median raphe nucleus.

Acute exposure to stress induces significant behavioural changes, while repeated exposure to the same stressor leads to the development of tolerance to stress. The development of tolerance appears to involve the serotonergic projections from the Median Raphe Nucleus (MnRN) to the dorsal Hippocampus (dH), since rats with lesions of this pathway does not develop tolerance to stress. Previous data from our laboratory showed that treatment with imipramine, a serotonin (5-HT) and noradrenaline (NA) reuptake inhibitor, lead to the development of tolerance. However, it remains to be elucidated whether such tolerance involves the participation of the noradrenergic system, apart from the serotonergic projections. Therefore, the aim of this work was to investigate the behavioural and neurochemical effects of chronic treatment with desipramine (NA reuptake inhibitor) or fluoxetine (5-HT reuptake inhibitor) in chronically stressed rats with lesions of the serotonergic neurons of the MnRN. Male Wistar rats with or without lesion in the MnRN were submitted or not to acute (2 h) or chronic restraint (2 h/seven days) stress and tested in the elevated pus maze (EPM). Treatment with fluoxetine, desipramine (10 mg/kg) or saline was performed twice daily (12-12 h interval), for 7 consecutive days. EPM test was conducted 24 h after the treatment. Fluoxetine attenuated the anxiogenic-induced effect of lesion in chronically restrained rats, without changing serotonin and noradrenaline levels in the hippocampus of lesioned rats. A similar profile was also observed after treatment with desipramine. These results suggest that both the serotonergic and the noradrenergic systems are involved in the development of tolerance to chronic stress. Additionally, the integrity of the serotonergic pathway of the MnRN-dH is not essential for the anxiolytic-like effects of these drugs.

Behavioral sensitization induced by dorsal periaqueductal gray electrical stimulation is counteracted by NK1 receptor antagonism in the ventral hippocampus and central nucleus of the amygdala.

A single threatening experience may change the behavior of an animal in a long-lasting way and elicit generalized behavioral responses to a novel threatening situation that is unrelated to the original aversive experience. Electrical stimulation (ES) of the dorsal periaqueductal gray (dPAG) produces a range of defensive reactions, characterized by freezing, escape, and post-stimulation freezing (PSF). The latter reflects the processing of ascending aversive information to prosencephalic structures, including the central nucleus of the amygdala (CeA), which allows the animal to evaluate the consequences of the aversive situation. This process is modulated by substance P (SP) and its preferred receptor, neurokinin 1 (NK1). The ventral hippocampus (VH) has been associated with the processing of aversive information and expression of emotional reactions with negative valence, but the participation of the VH in the expression of these defensive responses has not been investigated. The VH is rich in NK1 receptor expression and has a high density of SP-containing fibers. The present study examined the role of NK1 receptors in the VH in the expression of defensive responses and behavioral sensitization that were induced by dPAG-ES. Rats were implanted with an electrode in the dPAG for ES, and a cannula was implanted in the VH or CeA for injections of vehicle (phosphate-buffered saline) or the NK1 receptor antagonist spantide (100 pmol/0.2 µL. Spantide reduced the duration of PSF that was evoked by dPAG-ES, without changing the aversive freezing or escape thresholds. One and 7 days later, exploratory behavior was evaluated in independent groups of rats in the elevated plus maze (EPM). dPAG-ES in rats that received vehicle caused higher aversion to the open arms of the EPM compared with rats that did not receive dPAG stimulation at both time intervals. Injections of spantide in the VH or CeA prevented the proaversive effects of dPAG-ES in the EPM only 1 day later. These findings suggest that NK1 receptors are activated in both the VH and CeA during the processing of aversive information that derives from dPAG-ES. As previously shown for the CeA, SP/NK1 receptors in the VH are recruited during PSF that is evoked by dPAG-ES, suggesting that a 24-h time window is susceptible to interventions with NK1 antagonists that block the passage of aversive information from the dPAG to higher brain areas.

Inhibition of substance P-induced defensive behavior via neurokinin-1 receptor antagonism in the central and medial but not basolateral nuclei of the amygdala in male Wistar rats.

RATIONALE: The production of unconditioned defensive behaviors has been related to the amygdala, a key component of the encephalic aversion system. Microinjection of the neuropeptide substance P (SP) in the amygdala elicits defensive behaviors via the activation of type 1 neurokinin (NK-1) receptors. However, no studies have investigated whether intra-amygdala SP/NK-1 mechanisms can elicit other types of defensive responses, such as antinociception and ultrasonic vocalizations (USVs). METHODS: The present study investigated the effects of SP-induced activation of the neurokininergic system in three main nuclei of the amygdala-basolateral (BLA), central (CeA), and medial (MeA) nuclei-in rats that were subjected to the elevated plus maze (EPM), tail-flick test, and USV recording. The effects of SP in these amygdaloid nuclei were challenged with combined injections of the NK-1 receptor antagonist spantide. RESULTS: The present study showed that SP injections in the CeA and MeA but not BLA exerted anxiogenic-like effects. In contrast to the CeA, the anxiogenic-like effects of SP in the MeA were not dependent on NK-1 mechanisms. In the tail-flick test, SP microinjections produced antinociceptive effects only in the MeA through NK-1 receptor activation. No USV emissions were detected after the SP microinjections. CONCLUSIONS: The present study showed that NK-1 receptors in the CeA and MeA but not BLA are involved in defensive reactions to conditions of fear. The present results may provide a better understanding of the neurochemical mediation of fear states.

Microbiological Quality Assessment by PCR and Its Antibiotic Susceptibility in Mangrove Crabs (Ucides cordatus) from Guanabara Bay, Rio de Janeiro, Brazil.

The bacteriological quality of crabs from three different mangroves (Itaóca, Suruí, and Piedade) from Rio de Janeiro state, Brazil, was investigated using conventional and molecular methods. The results revealed high counts for total coliforms in meat and hepatopancreas samples. PCR analyses identified 25 Escherichia coli colonies in the Itaóca, Piedade, and Suruí samples, detecting 13 enterotoxigenic colonies and 9 enteroaggregative colonies. Respectively, 12, 11, and 21 Vibrio parahaemolyticus strains were detected in the Itaóca, Piedade, and Suruí samples. Two V. cholerae strains were detected in the Piedade samples. The E. coli strains isolated in the present study showed resistance to gentamicin. E. coli strains from the Piedade samples showed 33% resistance to chloramphenicol and the strains also showed multiresistance to several antimicrobial agents with a MAR index ranging from 0.12 to 0.31. Vibrio strains from Piedade, Itaóca, and Suruí showed 86%, 78%, and 85% resistance, respectively, to ampicillin. The isolated Vibrio strains showed multiresistance to several antimicrobial agents, with a MAR index ranging from 0.12 to 0.25. The presence of these organisms in crab meat is an indication of microbial contamination, which may pose health risks to consumers when improperly cooked.

Tolerance to repeated stress in rats with lesions of the serotoninergic neurons of the Median Raphe Nucleus and chronically treated with imipramine.

Repeated exposure to aversive events leads to the development of tolerance to stress, which involves the serotonergic pathway originated in the Median Raphe Nucleus (MnRN) to the Dorsal Hippocampus (DH). However, it is not clear whether these lesion-induced deficits can be attenuated by treatment with antidepressants. Therefore, the aim of this work was to investigate the effects of chronic treatment with Imipramine (IMI) in rats with lesions in the MnRN and exposed to restraint stress. Male Wistar rats with or without neurochemical lesions of the MnRN serotonergic neurons with the neurotoxin 5,7-DHT were submitted to acute (2h) or chronic restraint (2h/day/seven consecutive days) and treated with saline (1 ml/kg) or imipramine (15 mg/kg) via intraperitoneal twice a day during the same period. In acutely restrained rats, stress occurred on the last day of treatment. Test in the elevated plus maze (EPM) was performed 24h later. After EPM test, animals were sacrificed and had their brains removed. Dorsal hippocampus and striatum were dissected and the levels of 5-HT and 5-hydroxy-indoleacetic acid (5-HIAA) measured by HPLC analysis. Our results showed that in control rats exposure to acute restraint stress decreased exploration of the open and enclose arms of the EPM, an effect that was attenuated by imipramine. In rats with 5,7-DHT lesions, acute restraint did not change the exploration of the EPM, independently of the treatment. On the other hand, when chronically restrained, saline treated rat with 5,7-DHT lesion showed a reduced exploration of the open arms of the EPM. This effect was attenuated by simultaneous treatment with imipramine. HPLC analysis showed significantly decreases on 5-HT and 5-HIAA levels in the hippocampus, but not in the striatum. These later results confirm that 5,7-DHT lesions of the MnRN had significant impact on the serotonergic projections to the dorsal hippocampus which seems to be essential for the development of tolerance to repeated stress in the absence of any pharmacological treatment.

A high efficient protocol for soybean root transformation by Agrobacterium rhizogenes and most stable reference genes for RT-qPCR analysis.

KEY MESSAGE: A 55% transformation efficiency was obtained by our optimized protocol; and we showed that GmELF1 - ß and GmELF1 - α are the most stable reference genes for expression analyses under this specific condition. Gene functional analyses are essential to the validation of results obtained from in silico and/or gene-prospecting studies. Genetic transformation methods that yield tissues of transient expression quickly have been of considerable interest to researchers. Agrobacterium rhizogenes-mediated transformation methods, which are employed to generate plants with transformed roots, have proven useful for the study of stress caused by root phytopathogens via gene overexpression and/or silencing. While some protocols have been adapted to soybean plants, transformation efficiencies remain limited; thus, few viable plants are available for performing bioassays. Furthermore, mRNA analyses that employ reverse transcription quantitative polymerase chain reactions (RT-qPCR) require the use of reference genes with stable expression levels across different organs, development steps and treatments. In the present study, an A. rhizogenes-mediated soybean root transformation approach was optimized. The method delivers significantly higher transformation efficiency levels and rates of transformed plant recovery, thus enhancing studies of soybean abiotic conditions or interactions between phytopathogens, such as nematodes. A 55% transformation efficiency was obtained following the addition of an acclimation step that involves hydroponics and different selection processes. The present study also validated the reference genes GmELF1-ß and GmELF1-α as the most stable to be used in RT-qPCR analysis in composite plants, mainly under nematode infection.

Proximal tibia fracture in a patient with incomplete spinal cord injury associated with robotic treadmill training.

STUDY DESIGN: One case report of proximal tibia fracture in a patient with incomplete spinal cord injury (SCI) associated with robotic treadmill training. OBJECTIVE: To raise the awareness that bone densitometry may be recommended before starting the robotic treadmill therapy, as well as the active vigilance of symptoms after therapy. SETTING: Institute of Physical and Rehabilitation Medicine, Lucy Montoro Institute for Rehabilitation, Hospital das Clínicas, School of Medicine, University of São Paulo, São Paulo, Brazil. CASE REPORT: The patient, female gender, with a fracture of vertebra T12 and arthrodesis from T9 to L1 (American Spinal Injury Association Classification (ASIA-C)). Training on Lokomat consisted of five 30-min weekly sessions, under the supervision of a qualified professional. At the beginning of the 19th session, the patient complained of pain in the anterior region of the left knee. Lokomat and any other body support therapy were discontinued. Magnetic resonance imaging (MRI) evidenced a transverse, oblique, metaphyseal proximal anterior and medial tibial fracture. CONCLUSION: Fractures are among the chronic complications of a SCI, affecting 34% and many times arising from minimal traumas. Lokomat resembles physiological walking, and more studies show its benefits. Many studies encourage the use of robotic devices for the rehabilitation of lower limbs, but there are still several unanswered questions. However, there are not enough studies to show whether there is a higher risk of fracture incidence in patients with osteopenia or osteoporosis who trained on the Lokomat.

Dorsal periaqueductal gray post-stimulation freezing is counteracted by neurokinin-1 receptor antagonism in the central nucleus of the amygdala in rats.

Electrical stimulation of the dorsal periaqueductal gray (dPAG) in rats generates defensive responses that are characterized by freezing and escape behaviors, followed by post-stimulation freezing that resembles symptoms of panic attacks. dPAG post-stimulation freezing involves the processing of ascending aversive information to prosencephalic centers, including the amygdala, which allows the animal to evaluate the consequences of stressful situations. The basolateral nucleus of the amygdala (BLA) is thought to act as a filter for innate and learned aversive information that is transmitted to higher structures. The central (CeA) and medial (MeA) nuclei of the amygdala constitute an output for the expression of fear reactions through projections to limbic and brainstem regions. Neurokinin (NK) receptors are abundant in the CeA, MeA, and BLA, but their role in the expression of defensive responses and processing of aversive information that is evoked by electrical stimulation of the dPAG is still unclear. In the present study, we examined the role of NK1 receptors in these amygdala nuclei in the expression of defensive responses induced by electrical stimulation of the dPAG in rats and fear memory of this aversive stimulation. Rats were implanted with an electrode into the dPAG for electrical stimulation and one cannula in the CeA, MeA, or BLA for injections of vehicle (phosphate-buffered saline) or the NK1 receptor antagonist spantide (SPA; 100 pmol/0.2 µl). Injections of SPA into the CeA but not BLA or MeA reduced the duration of post-stimulation freezing evoked by electrical stimulation of the dPAG, without changing the aversive thresholds of freezing or escape. Twenty-four hours later, exploratory behavior was evaluated in the elevated plus maze test (EPM) in the CeA group of rats. Electrical stimulation of the dPAG rats that received vehicle exhibited higher aversion to the open arms of the EPM than sham rats that did not receive any dPAG stimulation. SPA injections into the CeA prevented the proaversive effects of electrical stimulation of the dPAG assessed in the EPM 24 h later. The present results suggest that neurokininergic modulation via NK1 receptors in the CeA but not BLA or MeA is involved in the processing of aversive information derived from dPAG stimulation. The long-lasting consequences of electrical stimulation of the dPAG may be prevented by NK1 receptor antagonism in the CeA.

Participation of NK1 receptors of the amygdala on the processing of different types of fear.

The amygdala, medial hypothalamus, dorsal periaqueductal gray (dPAG), superior and inferior colliculus together constitutes the encephalic aversion system which has been considered the main neural substrate for the integration of unconditioned aversive behavioral states. Within the amygdala the basolateral nucleus (BLA) is thought to act as a filter for innate and learned aversive information to higher structures, whereas the central nucleus (CeA) is considered the main output for the expression of fear reactions through projections to limbic and brainstem regions. Although neurokinin (NK) receptors are abundant in the amygdala, their role in the processing and expression of fear is yet unclear. In this study, we examined the role of SP/NK1 receptor system of the CeA and BLA on the expression of defensive responses elaborated by Wistar rats submitted to elevated plus maze (EPM) and to electrical stimulation (ES) of the dPAG. For EPM test, cannulae were implanted in the CeA and BLA for injections of substance P (SP - 10 and 100pmol/0.2µL) and spantide (SPA - 10, 100 and 500pmol/0.2µL). For ES of dPAG, aversive thresholds for freezing and escape responses as well as post-stimulation freezing (PSF) were measured in rats treated with PBS and SPA (100pmol/0.2µL) in CeA. Injections of SP into the CeA, but not the BLA, produced anxiogenic-like effects in the EPM test. SPA injected into the CeA had no effect on the exploratory behavior of rats submitted to the EPM but blocked the effects of SP. The duration of dPAG-PSF was also reduced significantly following injection of SPA in CeA but had no effect on thresholds for freezing and escape responses. The EPM gives the animal a control over its environment i.e. the option to choose or not to enter into the open arm and dPAG-PSF is thought to reflect a period when the animal evaluates the significance of dPAG-evoked aversion once the unconditioned responses of freezing and escape were elicited. The data indicate that SP may be involved in mediating responses of the animal in only certain types of aversive behavior and suggests a differential participation of the NK1 receptors in the processing of distinct types of fear in the amygdala.

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.

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.

Restriction modification (RM) tests associated to additional molecular markers for screening prevalent MRSA clones in Brazil.

In this study, we associated the restriction modification (RM) tests to the polymerase chain reaction (PCR) detection of molecular markers (SCCmec III, seh, agr II-SCCmec IV, and lukSF) for revealing the main methicillin-resistant Staphylococcus aureus (MRSA) clones circulating in Brazil. This simple and rapid approach allowed a precise classification of the MRSA analyzed when compared with pulsed-field gel electrophoresis (PFGE) data.

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.

Evidence of ecotypic differentiation between populations of the tree species Parapiptadenia rigida due to flooding.

The tree species Parapiptadenia rigida, native to southern South America, is frequently used in reforestation of riverbanks in Brazil. This tree is also a source of gums, tannins and essential oils, and it has some medicinal uses. We investigated flooding tolerance and genetic diversity in two populations of P. rigida; one of them was naturally exposed to flooding. Plants derived from seeds collected from each population were submitted to variable periods of experimental waterlogging and submergence. Waterlogging promoted a decrease in biomass and structural adjustments, such as superficial roots with aerenchyma and hypertrophied lenticels, that contribute to increase atmospheric oxygen intake. Plants that were submerged had an even greater reduction in biomass and a high mortality rate (40%). The two populations varied significantly in their RAPD marker profiles, in their ability to produce aerenchyma when waterlogged and to survive when submerged, suggesting ecotypic differentiation between them. Hence, the seasonal flooding that has been challenging the tropical riparian forest appears to be genetically modifying the P. rigida populations exposed to it by selecting individuals with increased ability to live under this condition.

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.

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%) of pattern A (BEC-related). However, MRSA harboring SCCmec type IV were also identified, 3 (7%) 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-beta-lactam antibiotics. However, emergence of multiresistant variants of USA800 was detected.

The anterior cingulate cortex is a target structure for the anxiolytic-like effects of benzodiazepines assessed by repeated exposure to the elevated plus maze and Fos immunoreactivity.

Prior experience with the elevated plus maze (EPM) increases the avoidance of rodents to the open arms and impairs the anxiolytic-like effects of benzodiazepines on the traditional behaviors evaluated upon re-exposure to the maze, a phenomenon known as one-trial tolerance. Risk assessment behaviors are also sensitive to benzodiazepines. During re-exposure to the maze, these behaviors reinstate the information-processing initiated during the first experience, and the detection of danger generates stronger open-arm avoidance. The present study investigated whether the benzodiazepine midazolam alters risk assessment behaviors and Fos protein distribution associated with test and retest sessions in the EPM. Naive or maze-experienced Wistar rats received either saline or midazolam (0.5 mg/kg i.p.) and were subjected to the EPM. Midazolam caused the usual effects on exploratory behavior, increasing exploratory activity of naive rats in the open arms and producing no effects on these conventional measures in rats re-exposed to the maze. Risk assessment behaviors, however, were sensitive to the benzodiazepine during both sessions, indicating anxiolytic-like effects of the drug in both conditions. Fos immunohistochemistry showed that midazolam injections were associated with a distinct pattern of action when administered before the test or retest session, and the anterior cingulate cortex, area 1 (Cg1), was the only structure targeted by the benzodiazepine in both situations. Bilateral infusions of midazolam into the Cg1 replicated the behavioral effects of the drug injected systemically, suggesting that this area is critically involved in the anxiolytic-like effects of benzodiazepines, although the behavioral strategy adopted by the animals appears to depend on the previous knowledge of the threatening environment.

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.