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The genus Agave sensu lato contains ca. 211 described species, many of which are considered keystone species because of their ecological dominance and the quantity of resources they provide with their massive, nectar-rich inflorescences. The large diversity of Agave species has been hypothesized as being related to their reproductive strategy (predominantly monocarpic) and diverse pollinators (e.g., bats, hummingbirds, hawkmoths). In particular, Agave species provide resources that a few genera of nectar feeding bats from the subfamily Glosophaginae are dependent upon. To explore a possible coevolutionary relationship between Agave and the bat species that pollinate them, we calibrated molecular phylogenies of both groups and looked for a correlation in their dates of divergence. One coding and two non-coding regions of the chloroplast genome were sequenced from 49 species of the Agavoideae (Asparagaceae), and the mitochondrial gene Cyt-b and nuclear coding gene RAG2 were either sequenced or obtained from gene bank for 120 Phyllostomid bats. Results from the analyses indicate that Agave sensu lato is a young genus (estimated crown age 2.7-8.5/stem age 4.6-12.3 Ma), with an increasing diversification rate, and the highest speciation rate among Agavoideae's clades. The origin of the Glossophaginae bats (stem age 20.3-23.5 Ma) occurred prior to the stem age of Agave sensu lato, while the origin of the current pollinators of Agave species, members of the genera Glossophaga, Leptonycteris, Anoura, Choeronyscus, Musonycteris and Choeronycteris, was estimated to be around 6.3-16.2 Ma, overlapping with the stem age of Agave sensu lato, supporting the hypothesis of diffuse coevolution.

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Type 1 diabetes mellitus (T1DM) is a disorder resulting from chronic autoimmune destruction of insulin-producing pancreatic ß-cells, lack of insulin production and hyperglycaemia. The aim of this study was to evaluate the hypothesis that streptozotocin-diabetic mice treated with Saccharomyces boulardii THT 500101 strain present improvement of glucose and triglycerides metabolism, reduction of liver inflammation concomitant with a beneficial impact in the gut microbiota profile. C57BL/6 male mice were randomly assigned into three groups: Control, Diabetes, Diabetes+Probiotic, and were euthanised 8 weeks after probiotic chronic administration. Mice submitted to treatment presented reduced glycemia in comparison with the diabetic group, which was correlated with an increase in C-peptide level and in hepatic glycogen content. Fat metabolism was significantly altered in streptozotocin-induced diabetic group, and S. boulardii treatment regulated it, leading to a decrease in serum triglycerides secretion, increase in hepatic triglycerides storage and modulation of inflammatory profile. The phenotypic changes seen from chronic S. boulardii treatment were found to be broadly associated with the changes in microbioma of diabetic animals, with increased proportion in Bacteroidetes, Firmicutes and Deferribacteres, and a decreased proportion of Proteobacteria and Verrucomicrobia phylum. Thus, the data presented here show up a novel potential therapeutic role of S. boulardii for the treatment and attenuation of diabetes-induced complications.

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BACKGROUND: The Meridional Hospital Liver transplant unit is the only one active in all Espírito Santo State, Brazil, since 2004. OBJECTIVE: The aim is to analyze data of the first 250 transplants performed by the team. METHODS: This retrospective study reviewed files from patients transplanted in the Meridional Hospital from January 2005 to December 2015. RESULTS: There were 250 liver transplants in 236 patients and 14 retransplants. 72.4% were male recipients, with average age of 51.1 years (1-70 years), and the main etiology was alcoholic cirrhosis (33.6% of the cases). Surgical reintervention occurred in 58 patients (include retransplantations) during the same hospitalization, with revision of homeostasis and retransplant as main indications. In the retransplant group, 73.3% of patients died within 2 months. Thrombosis of the hepatic artery was responsible for 40% of the indications for retransplant. The average time between first and second transplant was 223 days (median 14 days). Currently 152 of 236 patients are living, with 1-year life expectancy of approximately 71%. The mortality peak occurred from the immediate postoperative period to 2 months post-transplant (63.8% of the deaths). 32% of subjects did not need intraoperative blood transfusion. The average time of intensive care unit stay was of 8.52 days, and overall hospital stay was 21.7 (median 15 days). CONCLUSION: Despite the logistic difficulties and lack of donors our unit, keep in advance with survival comparable to other national centers (68% to 74% in 1-year).

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Experimental studies have reported that aerobic exercise after asthma induction reduces lung inflammation and remodeling. Nevertheless, no experimental study has analyzed whether regular/moderate aerobic training before the induction of allergic asthma may prevent these inflammatory and remodeling processes. For this purpose, BALB/c mice (n = 96) were assigned into non-trained and trained groups. Trained animals ran on a motorized treadmill at moderate intensity, 30 min/day, 3 times/week, for 8 weeks, and were further randomized into subgroups to undergo ovalbumin sensitization and challenge or receive saline using the same protocol. Aerobic training continued until the last challenge. Twenty-four hours after challenge, compared to non-trained animals, trained mice exhibited: (a) increased systolic output and left ventricular mass on echocardiography; (b) improved lung mechanics; (c) decreased smooth muscle actin expression and collagen fiber content in airways and lung parenchyma; (d) decreased transforming growth factor (TGF)-ß levels in bronchoalveolar lavage fluid (BALF) and blood; (e) increased interferon (IFN)-γ in BALF and interleukin (IL)-10 in blood; and (f) decreased IL-4 and IL-13 in BALF. In conclusion, regular/moderate aerobic training prior to allergic asthma induction reduced inflammation and remodeling, perhaps through increased IL-10 and IFN-γ in tandem with decreased Th2 cytokines.

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BACKGROUND AND OBJECTIVE: Protease activated receptor type 1 (PAR1 ) seems to play a role in periodontal repair, while PAR2 is associated with periodontal inflammation. As diabetes is a known risk factor for periodontal disease, the aim of this study was to evaluate the influence of type 2 diabetes on PAR1 and PAR2 mRNA expression in the gingival crevicular fluid of patients with chronic periodontitis before and after non-surgical periodontal treatment. MATERIAL AND METHODS: Gingival crevicular fluid samples and clinical parameters consisting of measuring probing depth, clinical attachment level, bleeding on probing and plaque index were collected from systemically healthy patients and patients with type 2 diabetes and chronic periodontitis, at baseline and after non-surgical periodontal therapy. PAR1 and PAR2 , as well as the presence of the proteases RgpB gingipain and neutrophil proteinase-3 were assessed by quantitative polymerase chain reaction in the gingival crevicular fluid. RESULTS: The periodontal clinical parameters significantly improved after periodontal therapy (p < 0.01). Diabetes led to increased expression of PAR1 in gingival crevicular fluid, and in the presence of chronic periodontitis, it significantly decreased the expression of PAR1 and PAR2 (p < 0.05). Moreover, non-surgical periodontal treatment in diabetics resulted in increased expression of PAR1 and PAR2 (p < 0.05), and decreased expression of RgpB gingipain and proteinase-3 (p < 0.05). CONCLUSION: The present data demonstrated that diabetes was associated with an altered expression of PAR1 and PAR2 in the gingival crevicular fluid cells of subjects with chronic periodontitis. Future studies are necessary to elucidate the effects of PAR1 upregulation in periodontally healthy sites and PAR2 downregulation in chronic periodontitis sites on the increased susceptibility and severity of periodontitis in diabetes.

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ABSTRACTIn this study, ethanol-water extracts of pequi fruit peel were fractionated in order to identify and quantify the major antioxidant present in it. The fractions were subjected to liquid-liquid phase extraction and silica-gel column chromatography, and antioxidant activity was monitored using the 2,2-diphenyl-1-picrylhydrazyl radical-scavenging assay. The purity of the fractions was evaluated using thin-layer chromatography and high-performance liquid chromatography (HPLC). The substance with antioxidant property was identified through the analysis in a liquid chromatography-mass spectroscopy fragmentation and was quantified using HPLC. After the Silica-gel fractionation, it was identified a fraction with high antioxidant activity and purity, which contained gallic acid as the main compound. The gallic acid was found at the amount of 26.54 ± 1.13 mg/g of the dry mass of the pequi fruit peel. Because the quantifications were performed using crude ethanol-water extract, it was suspected that gallic acid was present in a free form. Thus, pequi fruit peel may serve as an attractive alternative of feedstock for natural antioxidant production. Moreover, the results obtained in this study emphasize the value of the pequi plant, and suggests improved opportunities for families that use this fruit`s products.

RESUMOExtratos hidroetanólicos da casca do fruto do pequi foram fracionados a fim de identificar e quantificar o principal antioxidante presente. Frações do extrato foram submetidas ao particionamento líquido-líquido e fracionamento em coluna de sílica gel. As atividades antioxidantes das frações foram monitoradas usando ensaio de redução do radical 2,2-difenil-1-picrilhidrazila e a pureza das frações foi avaliada em cromatografia de camada delgada e cromatografia líquida de alta eficiência (CLAE). A substância com propriedades antioxidantes foi identificada através da análise em sistema de cromatografia líquida associada à espectrometria de massas e foi quantificada em HPLC. Após o fracionamento identificou-se uma fração com alta atividade antioxidante e pureza, contendo ácido gálico como o composto principal. Ácido gálico foi encontrado em concentrações de 26,54 ± 1,13 mg/g de massa seca. Devido às quantificações terem sido realizadas no extrato hidroetanólico bruto, acredita-se que o ácido gálico esteja presente na forma livre. Assim, a casca do fruto pequi pode servir como interessante alternativa de matéria prima para a produção desse antioxidante natural. Além disso, esse resultado enfatiza o valor da planta do pequi e sugere oportunidades para as famílias que utilizam produtos de pequi.

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OBJECTIVE: 1) To determine factors affecting adenosine deaminase (ADA) levels in pleural fluid (PF), and 2) to establish the optimal ADA cut-off level for a Brazilian population. DESIGN: ADA levels in PF of 309 patients were analysed to investigate pleural effusion. All patients were evaluated for age, sex and presence of tuberculosis (TB) based on a positive pleural biopsy. Differences in ADA levels between groups were analysed using Kruskal-Wallis one-way analysis of variance. Logistic regression analysis was also carried out to predict the occurrence of TB. ADA cut-off levels were selected using the receiver operating characteristic (ROC) curve. RESULTS: The mean PF ADA level was significantly higher in the tuberculous pleural group than in non-tuberculous pleural patients (63.3 ± 29 IU/l vs. 19 ± 31 IU/l, P < 0.001). There was a significant correlation between PF ADA levels and age: for patients aged ⩾45 years, the ROC curve for ADA had an area under the curve of 0.91. An ADA level of 29 IU/l resulted in a sensitivity of 88.6% and specificity of 91.5%. CONCLUSIONS: There is a significant negative correlation between PF ADA level and age. The use of a lower ADA cut-off reduces the number of false-negative results.

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BACKGROUND AND PURPOSE: Prostaglandin (PG) D(2) has emerged as a key mediator of allergic inflammatory pathologies and, particularly, PGD(2) induces leukotriene (LT) C(4) secretion from eosinophils. Here, we have characterized how PGD(2) signals to induce LTC(4) synthesis in eosinophils. EXPERIMENTAL APPROACH: Antagonists and agonists of DP(1) and DP(2) prostanoid receptors were used in a model of PGD(2) -induced eosinophilic inflammation in vivo and with PGD(2) -stimulated human eosinophils in vitro, to identify PGD(2) receptor(s) mediating LTC(4) secretion. The signalling pathways involved were also investigated. KEY RESULTS: In vivo and in vitro assays with receptor antagonists showed that PGD(2) -triggered cysteinyl-LT (cysLT) secretion depends on the activation of both DP(1) and DP(2) receptors. DP(1) and DP(2) receptor agonists elicited cysLTs production only after simultaneous activation of both receptors. In eosinophils, LTC(4) synthesis, but not LTC(4) transport/export, was activated by PGD(2) receptor stimulation, and lipid bodies (lipid droplets) were the intracellular compartments of DP(1) /DP(2) receptor-driven LTC(4) synthesis. Although not sufficient to trigger LTC(4) synthesis by itself, DP(1) receptor activation, signalling through protein kinase A, did activate the biogenesis of eosinophil lipid bodies, a process crucial for PGD(2) -induced LTC(4) synthesis. Similarly, concurrent DP(2) receptor activation used Pertussis toxin-sensitive and calcium-dependent signalling pathways to achieve effective PGD(2) -induced LTC(4) synthesis. CONCLUSIONS AND IMPLICATIONS: Based on pivotal roles of cysLTs in allergic inflammatory pathogenesis and the collaborative interaction between PGD(2) receptors described here, our data suggest that both DP(1) and DP(2) receptor antagonists might be attractive candidates for anti-allergic therapies.

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O objetivo deste trabalho foi analisar a sensibilidade antimicrobiana in vitro de cepas de Staphylococcus aureusisoladas de tetos de vacas e mãos de retireiros, além de verificar o polimorfismo entre elas pela técnica de PCR-RAPD. Os testes foram realizados pela técnica de difusão em discos e, após a extração do material genético foram desenvolvidas as técnicas de PCR e RAPD, usando para isso 40 iniciadores diferentes. A análise do polimorfismo foi realizada empregando-se o programa de taxonomia numérica NTSYS. As sensibilidades dos antimicrobianos nas cepas obtidas de tetos de vacas foram 4% para a penicilina, 88% para a tetraciclina, 92% para a gentamicina, 96% para a vancomicina e 100% ao cloranfenicol. Para as cepas provenientes das mãos de retireiros, os resultados de sensibilidade foram zero para a penicilina, 70% para a tetraciclina e 90% para a vancomicina e 100% para os antimicrobianos gentamicina e cloranfenicol. A realização do E-teste indicou uma concentração inibitória mínima (CIM) maior que 256 mg/mL para as cepas resistentes ao antimicrobiano vancomicina. Os estudos permitiram detectar a resistência dos S. aureus mediante o uso dos antimicrobianos testados e determinar a diversidade genética entre as cepas de estafilococos devido à presença de muitas bandas polimórficas encontradas em todos os iniciadores.

The aim of this study was to analyze in vitro antimicrobial susceptibility of Staphylococcus aureus strains isolated from teats of cow udders and milking workers' hands as well as to verify polymorphism among them by using RAPD-PCR technique. Tests were conducted by disk diffusion technique and after the collection of the genetic material PCR and RAPD techniques were performed with the use of 40 different initiators. The analysis of polymorphism was conducted by using the NTSYS program of numerical taxonomy. The susceptibility of antimicrobials in the strains collected from teats of cow udders was 4% to penicillin, 88% to tetracycline, 92% to gentamicine, 96% to vancomycin and 100% to chloranfenicol. As for the strains collected from milking workers' hands, susceptibility results were 0% to penicillin, 70% to tetracycline and 90% to vancomycin and 100% to gentamicine and chloranfenicol antimicrobials. E-test showed minimum inhibitory concentration (MIC) greater than 256 ?g/mL to strains resistant to the antimicrobial vancomycin. The studies made it possible to detect S. aureus resistance upon the use of the tested antimicrobials and to determine the genetic diversity found among strains of staphylococcus due to the presence of many polymorphic bands found in all initiators.

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ABSTRACT The aim of this study was to analyze in vitro antimicrobial susceptibility of Staphylococcus aureus strains isolated from teats of cow udders and milking workers hands as well as to verify polymorphism among them by using RAPD-PCR technique. Tests were conducted by disk diffusion technique and after the collection of the genetic material PCR and RAPD techniques were performed with the use of 40 different initiators. The analysis of polymorphism was conducted by using the NTSYS program of numerical taxonomy. The susceptibility of antimicrobials in the strains collected from teats of cow udders was 4% to penicillin, 88% to tetracycline, 92% to gentamicine, 96% to vancomycin and 100% to chloranfenicol. As for the strains collected from milking workers hands, susceptibility results were 0% to penicillin, 70% to tetracycline and 90% to vancomycin and 100% to gentamicine and chloranfenicol antimicrobials. E-test showed minimum inhibitory concentration (MIC) greater than 256 ?g/mL to strains resistant to the antimicrobial vancomycin. The studies made it possible to detect S. aureus resistance upon the use of the tested antimicrobials and to determine the genetic diversity found among strains of staphylococcus due to the presence of many polymorphic bands found in all initiators.

RESUMO O objetivo deste trabalho foi analisar a sensibilidade antimicrobiana in vitro de cepas de Staphylococcus aureusisoladas de tetos de vacas e mãos de retireiros, além de verificar o polimorfismo entre elas pela técnica de PCR-RAPD. Os testes foram realizados pela técnica de difusão em discos e, após a extração do material genético foram desenvolvidas as técnicas de PCR e RAPD, usando para isso 40 iniciadores diferentes. A análise do polimorfismo foi realizada empregando-se o programa de taxonomia numérica NTSYS. As sensibilidades dos antimicrobianos nas cepas obtidas de tetos de vacas foram 4% para a penicilina, 88% para a tetraciclina, 92% para a gentamicina, 96% para a vancomicina e 100% ao cloranfenicol. Para as cepas provenientes das mãos de retireiros, os resultados de sensibilidade foram zero para a penicilina, 70% para a tetraciclina e 90% para a vancomicina e 100% para os antimicrobianos gentamicina e cloranfenicol. A realização do E-teste indicou uma concentração inibitória mínima (CIM) maior que 256 mg/mL para as cepas resistentes ao antimicrobiano vancomicina. Os estudos permitiram detectar a resistência dos S. aureus mediante o uso dos antimicrobianos testados e determinar a diversidade genética entre as cepas de estafilococos devido à presença de muitas bandas polimórficas encontradas em todos os iniciadores.

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The effect of pH (from 4.8 to 9.8) on the production of pilosine and pilocarpine and on their partition between cell and medium was studied in two lineages (P and PP) of Pilocarpus microphyllus cell suspension cultures. Highest mass accumulation was observed at high pHs and both lineages produced pilocarpine while only lineage PP produced pilosine. Both alkaloids were released in the medium but higher accumulation occurred in the cells. The highest production of pilocarpine was at pH 8.8-9.8 in both cell lineages. Other imidazole alkaloids were also identified in both lineages. At all pHs tested, the pH in the media cultures tended to stabilize around 6 after 10-15 days of cultivation. NO3(-) and NH4+ variation in the media might partially explain the pH stabilization.

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ABSTRACT The aim of this work was to genetically characterize 1,073 isolates of B. thuringiensis, from three Brazilian collections UNESP/Jaboticabal, ESALQ/Piracicaba and EMBRAPA/Sete Lagoas with the main emphasis on the analysis of the cry1 gene types presented by these isolates. To achieve this purpose, oligonucleotide primers were designed based on 16 conserved and 4 unconserved regions of the corresponding sequences from each one of the 16 subclasses of the cry1 set of genes and used in PCR amplification assays. These sequences were amplified and the presence of amplicons for each subclass was evaluated in terms of percentage of gene type per bacterial collection. As a result, 55.7% of the isolates reacted to the primer Gral cry1, and the subclasses cry1Aa, cry1Ab, cry1Ac, cry1Ad, cry1Ae, cry1Af, cry1Ag, cry1Bf, cry1Ca and cry1Fa were detected in high percentages among the isolates ranging from 43.4 to 54.9%. A subclass distribution was observed among the set of isolates from these collections, with the greater percentage of isolates harboring the cry1Ab (42.12%) and the lowest percentage for thecry1Db subclass (0.6%). The genetic variability of the analyzed bacterial collections seems to indicate the ESALQ/Piracicaba and the UNESP/Jaboticabal subsets as sources of promising isolates for the control of Lepidoptera pest insects. For the EMBRAPA/Sete Lagoas subset of isolates, in which the evaluated subclasses frequencies were considered low (below 20%), the cry1B was the most frequently observed gene type present in 38.5% of the isolates.

RESUMO O presente trabalho teve como objetivo caracterizar geneticamente 1.073 isolados de Bacillus thuringiensis, de três coleções brasileiras, provenientes da UNESP, Jaboticabal, da ESALQ/ Piracicaba e da EMBRAPA. Sete Lagoas, analisando os tipos de genes cry1 apresentados pelos isolados. Para isso, foram elaborados oligonucleotídeos iniciadores a partir de 16 regiões conservadas e 4 regiões não conservadas das seqüências de cada uma das 16 subclasses do gene cry1. Essas seqüências foram amplificadas por PCR e a presença de amplicons para cada subclasse foi calculada em porcentagem por gene e por coleção. Nessa análise, 55,7% dos isolados apresentaram amplificação para o gene cry1, e as subclassescry1Aa, cry1Ab, cry1Ac, cry1Ad, cry1Ae, cry1Af, cry1Ag, e cry1Bf, cry1Ca e cry1Fa estão presentes em alta proporção de isolados, variando de 43,4% a 54,9%. Verificou-se que existe uma distribuição das subclasses dentro do banco de isolados de B. thuringiensis em estudo, com maior porcentagem de isolados portadores dos genes cry1Ab (42,12%) e com menor porcentagem de representantes da subclasse cry1Db (0,6%). A variabilidade gênica, nas coleções analisadas, destaca as coleções de Jaboticabal e Piracicaba como fontes de isolados promissores para uso em programas de Controle Biológico de pragas da ordem Lepidoptera. A coleção de Sete Lagoas, na qual as freqüências das subclasses estudadas foram relativamente baixas (abaixo de 20%), destaca somente o gene cry1Ab, presente em 38,5% dos isolados desta coleção.

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Jaborandi (Pilocarpus microphyllus) is a species that naturally occurs in the North and Northeast of Brazil, whose leaves produce pilocarpine (an imidazole alkaloid that has been used to treat glaucoma and xerostomy), the biosynthesis of which is still uncertain. The aim of this work was to establish cell lineages and select them according to an alkaloid profile similar to the one from Jaborandi leaves. The induction of callus was done in different culture media and growth regulators. Calluses from primary cultures or those subcultured several times were used as explants for the obtainment of six cell lineages. Alkaloids content analyses and growth curves showed that lines obtained from primary cultures produced more alkaloids and a better development. Cell lines from 12 subcultures presented a decrease in pilocarpine and pilosine production. After 24 subcultures, the production of alkaloids remained constant. ESI-MS analysis showed that cell culture extracts have the same alkaloid composition as extracts made from leaves. The results indicate that cell suspensions can be used as a model to study the biosynthesis of the imidazole alkaloid in P. microphyllus.

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Acetylcholinesterase (AChE) plays a key role in cholinergic impulse transmission, and it is the target enzyme for organophosphorus and carbamate insecticides. Two genes, AceI and AceII, have been characterized from different insect species, and point mutations in either gene can lead to significant resistance to these classes of insecticides. In this report, we describe the partial characterization of the AceI gene from Lutzomyia longipalpis (Lutz & Neiva) (Diptera: Psychodidae), and we show that the possibility exists for the development of a resistant phenotype to organophosphates and carbamates in sand flies. Our results point to the presence of a single AceI gene in L. longipalpis (LlAce1) and that AChE activity is inhibited by organophosphorus at a concentration of 5 x 10(-5) M. Regarding insecticide resistance, analysis of the truncated LlAce1 cDNA suggests that a single missense mutation leading to a glycine-to-serine substitution at amino acid position 119 (G119S) may arise in L. longipalpis, similar to what has been detected in Anopheles gambiae s.s. Another missense mutation involved in resistant phenotypes, F331W, detected in Culex tritaeniorhynchus Giles, is less likely to occur in L. longipalpis, because it faces codon constraint in this sand fly species. Comparison of the three-dimensional structures of the deduced amino acid sequence of the truncated LLAChE1 with that of An. gambiae and Cx. tritaeniorhynchus also suggests that similar structural modifications due to the missense amino acid changes in the active site gorge are detected in all three insects.

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In a study of the phlebotomine sandflies (Diptera: Psychodidae) in a forest reserve in Recife, Pernambuco state, north-eastern Brazil, the sandflies landing on human bait between 1.00 and 1.42 h after sunset were collected weekly for 2 years. Although 10,287 sandflies of 10 Lutzomyia species were collected, almost all (96.5%) of the sandflies caught were Lu. umbratilis. This species and several others caught are potential vectors of some of the Leishmania parasites that cause human disease. The recorded landing rate for Lu. umbratilis peaked, at the high level of 333.3 flies/person-hour, during the collections made in May 2003.The relative rarity in the collections of males of some of the species caught probably indicates that these species do not lek on their bloodmeal sources. It is likely that the sizes of the local populations of species that are not very anthrophilic, such as Lu. flaviscutellata, are much larger than indicated by the collections made on human bait.

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AIM: Auditory mid-latency response (MLR) has been studied in temporal lobe epileptic patients in order to evaluate the relationship between the different components of this evoked response and their probable generators in the most rostral part of auditory pathway. PATIENTS AND METHODS: MLR was studied in eight patients with temporal lobe epilepsy before lobectomy, and 1, 6 and 12 months after the surgical treatment, and eight healthy subjects matched for age and gender. Recording electrodes were placed in Cz, T3 and T4 according to the international 10-20 system. Comparisons were carried out in terms of peak to peak amplitude, latency and interpeak intervals of the main components (Mann-Whitney U test, Wilcoxon test). RESULTS: Epileptic patients showed statistically significant prolonged latency of all components, and increased Pa-Pb interpeak interval duration respect to control group. No significant variations were found in the amplitude of the studied components. There were no differences between left and right lobotomized patients. However, a marked tendency to the shortening of latency was observed in the left group after the surgical treatment. CONCLUSIONS: The differences between the pre-surgical records of patients and controls reflect an impaired activity in the generating areas for MLR components. There appears to be a trend to a different behaviour after right or left lobectomy, probably related to the extension of the removed tissue.

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AIMS: Given the diversity of criteria regarding the use of the midlatency auditory evoked potential (MLAEP) for diagnostic purposes, we carry out a review of the subject and highlight areas such as the generators of fundamental components, the conditions in which responses are obtained, factors that can modify results and the clinical uses that have been reported. DEVELOPMENT: There seems to be a strong tendency towards considering areas of the primary and secondary auditory cortex as generators of the response, with the subcortical structures playing a moderating role. Factors such as age, the method of stimulation used and the monitoring conditions can all exert an influence on the characteristics of this evoked response and modify its capacity for detection and repetition. Clinical uses of this potential range from the detection of the hearing threshold, monitoring the depth of anaesthesia, the functional evaluation of cochlear implants, and the diagnosis of neurological disorders, among others. CONCLUSIONS: MLAEP is a technique that is widely used in the study of the most rostral segments of the auditory pathway and this information complements that provided by short latency responses and increases the diagnostic sensitivity of auditory evoked potentials.

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Xylella fastidiosa is a xylem-dwelling, insect-transmitted, gamma-proteobacterium that causes diseases in many plants, including grapevine, citrus, periwinkle, almond, oleander, and coffee. X. fastidiosa has an unusually broad host range, has an extensive geographical distribution throughout the American continent, and induces diverse disease phenotypes. Previous molecular analyses indicated three distinct groups of X. fastidiosa isolates that were expected to be genetically divergent. Here we report the genome sequence of X. fastidiosa (Temecula strain), isolated from a naturally infected grapevine with Pierce's disease (PD) in a wine-grape-growing region of California. Comparative analyses with a previously sequenced X. fastidiosa strain responsible for citrus variegated chlorosis (CVC) revealed that 98% of the PD X. fastidiosa Temecula genes are shared with the CVC X. fastidiosa strain 9a5c genes. Furthermore, the average amino acid identity of the open reading frames in the strains is 95.7%. Genomic differences are limited to phage-associated chromosomal rearrangements and deletions that also account for the strain-specific genes present in each genome. Genomic islands, one in each genome, were identified, and their presence in other X. fastidiosa strains was analyzed. We conclude that these two organisms have identical metabolic functions and are likely to use a common set of genes in plant colonization and pathogenesis, permitting convergence of functional genomic strategies.

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PCR has been used to analyze the distribution of REP (Repetitive Extragenic Palindromic) and ERIC (Enterobacterial Repetitive Intergenic Consensus) sequences (rep-PCR) found within the genome of the bacterium Bacillus thuringiensis, with the purpose to analyze the genetic similarities among 56 subspecies samples and 95 field isolates. The PCR products were analyzed by EB-AGE (ethidium bromide-agarose electrophoresis) and then submitted to banding comparisons, based on the Phyllip software algorithm. When the banding similarities were considered for comparison purposes among all the strains, the phylogenic tree patterns varied according to the rep-PCR primers considered, but, from a broader point of view, the ERIC sequences produced better results, which, together with electron microscopy analysis of the released parasporal bodies and colony morphology characteristics, allowed to detect two possible new subspecies of B. thuringiensis

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