Application of polyurethane-based devices as sorption-desorption phases for microextraction analysis - The all-in-one microextraction concept.

In this work, polyurethane-based (PU) devices having cylindrical geometry soaked with suitable organic solvents are proposed for microextraction analysis. This novel analytical approach (PU microextraction; PUµE) operates under the floating sampling technology for extraction, followed by mechanical compression using a manual syringe for back-extraction. To test the performance of the PUµE method, two series of priority contaminants were used as model compounds (group #1: metalaxyl-M, penconazole and tebuconazole; group #2: atrazine, terbuthylazine, alachlor and benzo[a]pyrene) and extracted from aqueous samples followed by gas chromatography-mass spectrometry (GC-MS) analysis. The preparation of the PUµE devices and the device handling procedures are described. Also, the optimization experiments as well as the application of the new method to real matrices are discussed. Assays performed on 25mL water samples spiked at trace levels yielded average recoveries ranging from (50.1±6.7) % to (93.3±1.6) %, under optimized experimental conditions. The analytical performance showed good detection limits (0.01-0.50µg/L) and linear dynamic ranges (0.1-50.0µg/L) with acceptable determination coefficients (r2>0.9937). Excellent repeatability was also achieved in both intraday (RSD<3.5%) and inter-day (RSD<7.0%) experiments. With standard addition quantification, the proposed analytical approach revealed good sensitivity and selectivity at trace levels with absence of matrix effects for environmental water and wine samples. The PUµE technique is simple, cost-effective and very easy to apply, using an all-in-one microextraction concept.

Isolation and Characterization of Madariaga Virus from a Horse in Paraíba State, Brazil.

Madariaga virus (MADV), the new species designation for the South American isolates of eastern equine encephalitis virus (EEEV), is genetically divergent and substantially different in ecology and pathogenesis from North American EEEV strains. We isolated and characterized a MADV isolate obtained from a horse in Brazil. Our results support previous phylogenetic studies showing there are three genetically distinct MADV lineages. The MADV isolate from Paraíba State belongs to the South American lineage III and is closely related to Peruvian, Colombian and Venezuelan isolates.

Genetic divergence of sugarcane varieties collected in the region of Lavras, Minas Gerais, Brazil.

Genetic diversity among local accessions and varieties subsidize plant breeding programs, allowing the utilization of existing variability in plants that have already adapted to local climate conditions. An alternative to studying genetic variability is the study of diversity. The aim of this research was to study genetic diversity among sugarcane accessions and varieties used for the production of craft-distilled cachaça (distilled sugarcane alcohol) in the region of Lavras, Minas Gerais, Brazil. Using a one-way design, an experiment was conducted in the municipality of Perdões, Minas Gerais to evaluate 35 regional accessions derived from germplasm collection expeditions and four varieties. Using morphological descriptions of 46 multicategorical sugarcane characteristics, dissimilarity and Tocher cluster method analyses were performed. Based on the results, it was concluded that genetic diversity exists among the accessions evaluated for the target traits.

Do morphological and physiological characteristics of males of the dragonfly Macrothemis imitans determine the winner of territorial contests?

Males of many animal species show intraspecific disputes for mating territories that range from displays without physical contact to physical fights with risk of injury. This variation motivated the proposition of different models that suggest possible rules used by rivals to decide the contest winner. To evaluate those models, it is necessary to identify how males behave during the fight and the individual attributes that determine their fighting ability (resource holding potential). For this, males of the dragonfly Macrothemis imitans (Karsch) (Odonata: Libellulidae) were used to evaluate two hypotheses conditioned on the occurrence of physical contact during the fight: if the contests occur with physical contact, features related to size should determine male resource holding potential, and if males do not exhibit physical contact during the contests, features that confer greater endurance should determine resource holding potential. To assess these hypotheses, we collected males that had ownership of territories (resident males) and males that occupied the territory after we removed the resident males (substitute males). After the capture, the resident and substitute males were transferred to the laboratory for measurements of wing area, dry weight, thoracic muscle mass, and fat content. The results showed that resident males do not differ in any measured trait from substitutes. Because the fights occur with physical contact, it is intriguing that resident males do not possess higher fighting capacity than intruders. Perhaps physical contact does not incur high costs during the fight, and other asymmetries, such as motivation associated with prior residency of the disputed territory, determine the contest winner.

Impact of coagulation in the development of thromboembolic events in patients with spinal cord injury.

STUDY DESIGN: Although the knowledge described about risk factors and venous thromboembolism (VT) in the general population, the impact of these factors in the development of thromboembolic events in patients with spinal injury (SI) caused by spinal cord injury (SCI) is poorly understood. OBJECTIVE: Evaluate the impact of risk factors in the development of thromboembolic events in patients with SCI. SETTING: Brazil, São Paulo. METHODS: Observational, prospective and cross-study. Eligible patients (n=100) had SI by SCI, >18 years. The degree of motor and sensory lesion was evaluated based on American Spinal Injury Association (ASIA) Impairment Scale (AIS). Blood samples were collected for coagulation exams, hemogram, laboratory and biochemical analyses. Ultrasonography analyzes were performed from deep and superficial venous systems of lower limbs. Quantitative real-time PCR experiments were performed in order to investigate mutations in the prothrombin (G20210A) and Leiden factor V (G1691A) genes. RESULTS: The main finding of this study was the higher occurrence of deep venous thrombosis (DVT) in patients with Leiden factor V and hyperhomocysteinemia. There was no association between SI for DVT, VT and thrombophilia. Also, there was no relation between lupus anticoagulant and anti-cardiolipin. CONCLUSION: There is an important difference in the incidence of DVT in patients with SI by acute and chronic SCI. Therefore, the conduct of the investigation for thrombophilia should be based on clinical factors, risk factors for DVT and family history of thrombosis.

Recent advances in Schistosoma genomics.

Schistosome research has entered the genomic era with the publications reporting the Schistosoma mansoni and Schistosoma japonicum genomes. Schistosome genomics is motivated by the need for new control tools. However, much can also be learned about the biology of Schistosoma, which is a tractable experimental model. In this article, we review the recent achievements in the field of schistosome research and discuss future perspectives on genomics and how it can be integrated in a usable format, on the genetic mapping and how it has improved the genome assembly and provided new research approaches, on how epigenetics provides interesting insights into the biology of the species and on new functional genomics tools that will contribute to the understanding of the function of genes, many of which are parasite- or taxon specific.

Phenotypic screen of early-developing larvae of the blood fluke, schistosoma mansoni, using RNA interference.

RNA interference (RNAi) represents the only method currently available for manipulating gene-specific expression in Schistosoma spp., although application of this technology as a functional genomic profiling tool has yet to be explored. In the present study 32 genes, including antioxidants, transcription factors, cell signaling molecules and metabolic enzymes, were selected to determine if gene knockdown by RNAi was associated with morphologically definable phenotypic changes in early intramolluscan larval development. Transcript selection was based on their high expression in in vitro cultured S. mansoni primary sporocysts and/or their potential involvement in developmental processes. Miracidia were allowed to transform to sporocysts in the presence of synthesized double-stranded RNAs (dsRNAs) and cultivated for 7 days, during which time developing larvae were closely observed for phenotypic changes including failure/delay in transformation, loss of motility, altered growth and death. Of the phenotypes evaluated, only one was consistently detected; namely a reduction in sporocyst size based on length measurements. The size-reducing phenotype was observed in 11 of the 33 (33%) dsRNA treatment groups, and of these 11 phenotype-associated genes (superoxide dismutase, Smad1, RHO2, Smad2, Cav2A, ring box, GST26, calcineurin B, Smad4, lactate dehydrogenase and EF1alpha), only 6 demonstrated a significant and consistent knockdown of specific transcript expression. Unexpectedly one phenotype-linked gene, superoxide dismutase (SOD), was highly induced ( approximately 1600-fold) upon dsRNA exposure. Variation in dsRNA-mediated silencing effects also was evident in the group of sporocysts that lacked any definable phenotype. Out of 22 nonphenotype-expressing dsRNA treatments (myosin, PKCB, HEXBP, calcium channel, Sma2, RHO1, PKC receptor, DHHC, PepcK, calreticulin, calpain, Smeg, 14.3.3, K5, SPO1, SmZF1, fibrillarin, GST28, GPx, TPx1, TPx2 and TPx2/TPx1), 12 were assessed for the transcript levels. Of those, 6 genes exhibited consistent reductions in steady-state transcript levels, while expression level for the rest remained unchanged. Results demonstrate that the efficacy of dsRNA-treatment in producing consistent phenotypic changes and/or altered gene expression levels in S. mansoni sporocysts is highly dependent on the selected gene (or the specific dsRNA sequence used) and the timing of evaluation after treatment. Although RNAi holds great promise as a functional genomics tool for larval schistosomes, our finding of potential off-target or nonspecific effects of some dsRNA treatments and variable efficiencies in specific gene knockdown indicate a critical need for gene-specific testing and optimization as an essential part of experimental design, execution and data interpretation.

Effects of sample re-sequencing and trimming on the quality and size of assembled consensus sequences.

The production of nucleic acid sequences by automatic DNA sequencer machines is always associated with some base-calling errors. In order to produce a high-quality DNA sequence from a molecule of interest, researchers normally sequence the same sample many times. Considering base-calling errors as rare events, re-sequencing the same molecule and assembling the reads produced are frequently thought to be a good way to generate reliable sequences. However, a relevant question on this issue is: how many times the sample needs to be re-sequenced to minimize costs and achieve a high-fidelity sequence? We examined how both the number of re-sequenced reads and PHRED trimming parameters affect the accuracy and size of final consensus sequences. Hundreds of single-pool reaction pUC18 reads were generated and assembled into consensus sequences with CAP3 software. Using local alignment against the published pUC18 cloning vector sequence, the position and number of errors in the consensus were identified and stored in MySQL databases. Stringent PHRED trimming parameters proved to be efficient for the reduction of errors; however, this procedure also decreased consensus size. Moreover, re-sequencing did not have a clear effect on the removal of consensus errors, although it was able to slightly increase consensus.

Thrombocytopenia in patients with dengue virus infection in the Brazilian Amazon.

Thrombocytopenia may be occasionally observed in dengue fever (DF) but is a constant feature and one of the diagnostic criteria of dengue hemorrhagic fever (DHF). Its clinical presentation and relevance is still poorly described in the literature. Patients with fever and bleeding were referred to a tertiary care center in Manaus, in the Western Brazilian Amazon during the outbreak of dengue in 2001. They were hospitalized for clinical observation and supportive care. Platelet counts were performed on admission and throughout the hospitalization. Only patients with a serological confirmation or viral isolation of the dengue virus were included. One hundred and seventy eight patients were enrolled in the study (118 with DF and 60 with DHF). There was no association between the presence of active bleeding and the degree of thrombocytopenia on admission (P = 0.302). A positive tourniquet test, hematemesis and ecchymoses were more frequent in DHF patients (P < 0.05). Patients with DHF had lower platelet counts than patients with DF (P < 0.001). There was a positive correlation between platelet counts and plasma albumin levels (r = 0.217; P = 0.016) and a negative correlation with ALT values (r = -0.3; P = 0.001). Clinical manifestations of thrombocytopenia are not related only to the number of peripheral platelets in dengue infection, but its recovery is associated with clinical improvement. The level of platelets correlates with the vascular leakage of proteins and liver damage.

Effects of sample re-sequencing and trimming on the quality and size of assembled consensus sequences

The production of nucleic acid sequences by automatic DNA sequencer machines is always associated with some base-calling errors. In order to produce a high-quality DNA sequence from a molecule of interest, researchers normally sequence the same sample many times. Considering base-calling errors as rare events, re-sequencing the same molecule and assembling the reads produced are frequently thought to be a good way to generate reliable sequences. However, a relevant question on this issue is: how many times the sample needs to be re-sequenced to minimize costs and achieve a high-fidelity sequence? We examined how both the number of re-sequenced reads and PHRED trimming parameters affect the accuracy and size of final consensus sequences. Hundreds of single-pool reaction pUC18 reads were generated and assembled into consensus sequences with CAP3 software. Using local alignment against the published pUC18 cloning vector sequence, the position and number of errors in the consensus were identified and stored in MySQL databases. Stringent PHRED trimming parameters proved to be efficient for the reduction of errors; however, this procedure also decreased consensus size. Moreover, re-sequencing did not have a clear effect on the removal of consensus errors, although it was able to slightly increase consensus.

Diversity of the ground-dwelling ant fauna (Hymenoptera: Formicidae) of a moist, montane forest of the semi-arid Brazilian Nordeste

Although the so called "green islands" of the semi-arid Brazilian "Nordeste" are economically, socially, and ecologically important, relatively little is known about their biodiversity. We present the results of the first survey of the ground-dwelling ant fauna of a secondary forest in the Serra de Baturité (4° 05’ - 4° 40’ S / 38° 30’ - 39° 10’ W), among the biggest of the moist, montane forests of the state of Ceará, Brazil. From February to March 2001, samples were taken every 50 m along twelve 200 m transects, each separated from the others by at least 50 m and cut on either side of a recreational trail. Where possible, two transects were cut from the same starting point on the trail, one on either side. At each sample site two methods were used, as recommended in the ALL protocol: a pitfall trap and the treatment of 1 m² of leaf litter with the Winkler extractor. The myrmecofauna of the Serra de Baturité is quite diverse: individuals from 72 species, 23 genera, and six subfamilies were collected. The observed patterns of specific richness show the same tendencies noted in other tropical regions, particularly the frequency of capture distribution with many rare and few abundant species. Differences with the Atlantic and Amazonian forests were also observed, especially the relative importance of the Ponerinae and Formicinae subfamilies, indicating a possible influence of the surrounding "caatinga" (savanna-like ecosystem) on the myrmecofauna of the moist, montane forest

Se presentan los resultados del primer inventario de la mirmecofauna del suelo en un parche de bosque montano húmedo del "Nordeste" semi-árido brasileño. Aunque estos parches o "islas verdes" son importantes económica, social, y ecológicamente, se conoce relativamente poco acerca de su biodiversidad. La investigación fue llevada a cabo en un bosque secundario en la Serra de Baturité, uno de los mayores del bosque montano húmedo del estado de Ceará, Brazil. La mirmecofauna de Serra de Baturité es muy diversa: encontramos individuos de 72 especies, 23 géneros y seis fsubfamilias. Los patrones de riqueza específica muestran las mismas tendencias de otras regiones tropicales, particularmente en la distribución de frecuencia de capturas, con muchas especies escasas y unas pocas especies abundantes. También hay diferencias con los bosques atlántico y amazónico, especialmente en cuanto a la importancia relativa de las subfamilias Ponerinae y Formicinae, lo que indica una posible influencia de la "caatinga" (ecosistema semejante a la sabana) cercana en la mirmecofauna del bosque montano húmedo

Diversity of the ground-dwelling ant fauna (Hymenoptera: Formicidae) of a moist, Montane forest of the semi-arid Brazilian "Nordeste".

Although the so called "green islands" of the semi-arid Brazilian "Nordeste" are economically, socially, and ecologically important. relatively little is known about their biodiversity. We present the results of the first survey of the ground-dwelling ant fauna of a secondary forest in the Serra de Baturité (4 degrees 05'-4 degrees 40' S / 38 degrees 30'-39 degrees 10' W), among the biggest of the moist, montane forests of the state of Ceará, Brazil. From February to March 2001, samples were taken every 50 m along twelve 200 m transects, each separated from the others by at least 50 m and cut on either side of a recreational trail. Where possible, two transects were cut from the same starting point on the trail, one on either side. At each sample site two methods were used, as recommended in the ALL. protocol: a pitfall trap and the treatment of 1 m2 of leaf litter with the Winkler extractor. The myrmecofauna of the Serra de Baturité is quite diverse: individuals from 72 species, 23 genera, and six subfamilies were collected. The observed patterns of specific richness show the same tendencies noted in other tropical regions, particularly the frequency of capture distribution with many rare and few abundant species. Differences with the Atlantic and Amazonian forests were also observed, especially the relative importance of the Ponerinac and Formicinae subfamilies, indicating a possible influence of the surrounding "caatinga" (savanna-like ecosystem) on the myrmecofauna of the moist, montane forest.

Expression of gelatinases A and B, stromelysin-3 and matrilysin genes in breast carcinomas: clinico-pathological correlations.

The purpose of this study was to investigate the association among matrix metalloproteinases (gelatinases A and B, stromelysin-3 (ST3) and matrilysin) mRNAs expressed in primary breast carcinomas and standard prognostic parameters and clinical outcome. mRNA levels were determined by Northern analysis in samples of 81 breast cancer patients (median follow-up, 40 months) and 27 samples of uninvolved adjacent breast tissue. Proteases were expressed by the majority of the tumors and normal breast tissues examined. ST3, gelatinase A and matrilysin mRNAs were more often expressed at high levels in carcinomatous than in normal breast tissues. Differences in the distribution of gelatinase B mRNA were not found. However, paired normal tissues generally produced weaker signals when compared to matched tumor samples. Univariate analysis showed no significant association of gelatinase A and matrilysin mRNAs with the classical prognostic markers (age, menopausal status, stage, size, nodal status, vascular infiltrate, necrosis, steroid receptors, metastasis and survival). Overexpression of ST3 was more frequently found in tumors of post-menopausal women (P < 0.022). Elevated expression of gel B mRNA was associated with the presence of vascular infiltrate (P < 0.026), necrosis (P < 0.039), PR negative tumors (P < 0.014) and inversely correlated to the number of survivors (P < 0.021). Multivariate analysis including 68 patients for whom all information was available indicated that neither stromelysin correlated significantly with pathological, clinical or biochemical features. High levels of gelatinase A and B mRNAs were inversely associated with the number of survivors. Our findings suggest that measurements of gelatinase A and B mRNAs expression in breast carcinoma may help to identify patients with an aggressive form of the disease.

Morte súbita de caprinos por enterotoxemia / Sudden death of goats due to enterotoxaemia

Descreve-se a ocorrência de morte súbita observada em uma criaçäo de caprinos. A maioria das mortes ocorreu sem qualquer manifestaçäo sintomática prévia; entretanto, em alguns casos observou-se incoordenaçäo motora, eliminaçäo de cíbalas envoltas em fragmentos de mucosa intestinal e diarréia. Nos momentos que antecediam à morte, alguns animais emitiam fortes berros. O isolamento de um bacilo anaeróbio, Gram-positivo e bioquimicamente identificado como Clostridium perfringens, foi possível a partir de amostras de materiais coletadas em diferentes porçöes dos intestinos, retículo e também da raçäo. Nos filtros obtidos dos conteúdos dos órgäos citados, evidenciou-se a presença, em alta dosagem, de uma toxina termolábil e letal para camundongos. A necrópsia, observaram-se compartimentos gástricos plenos de alimento e hemorragias na mucosa intestinal. Estas constataçöes, associadas aos resultados laboratoriais, possibilitaram concluir tratar-se de um quadro de enterotoxemia

Avaliaçäo do sistema de vigilância epidemiológica para a febre aftosa em Goiás no período 1980-1990 / Avaliation of epidemiologic surveillance service to the foot-and-mouth disease in Brazil from 1980 to 1990

Analisou-se o sistema de vigilância em Goiás, de 1980 a 1990, tendo como referência a febre aftosa. Avaliaram-se os aspectos origem das notificaçöes, tipo de diagnóstico, duraçäo dos focos, intervalo entre início e notificaçäo dos focos e primeira visita do veterinário. Verificaram-se tendência decrescente das notificaçöes, predomínio dos registros realizados pelos proprietários, baixo percentual de diagnóstico laboratorial e elevado intervalo entre o início dos focos, sua notificaçäo e assistência. Discutiu-se o modelo avaliado e sugeriu-se a incorporaçäo de outros indicadores (bioprodutivos, econômicos e demográficos) nos sistemas vigentes