Daily Activity Patterns of Two Co-Occurring Tropical Satyrine Butterflies

Adult males and females of many insect species are expected to adjust their daily activity pattern in order to avoid stressful climatic conditions and increase the chances to encounter sexual partners. Using scan sampling methods associated with focal individual observations it was found that two satyrine butterflies of similar size and morphology, Hermeuptychia hermes (Fabricius) (Leptidoptera: Nymphalidae) and Paryphthimoides phronius (Godart), show completely different daily activity patterns on forest edges in southeastern Brazil. Hermeuptychia hermes presents one abundance peak in the morning and another in the late afternoon, while P. phronius abundance peaks in the mid-day, remaining stable until 1700 h. This difference is probably due to the occurrence of territorial behavior in the later species. The beginning of territorial defense by P. phronius males coincided with the time of new-born female activity. However, newly hatched females were not sexually receptive. The afternoon territoriality in male P. phronius may be in part related to mate acquisition. However, why the abundance of H. hermes decreases when the abundance of P. phronius increases is less clear

Molecular Binding Mechanism of TtgR Repressor to Antibiotics and Antimicrobials

A disturbing phenomenon in contemporary medicine is the prevalence of multidrug-resistant pathogenic bacteria. Efflux pumps contribute strongly to this antimicrobial drug resistance, which leads to the subsequent failure of clinical treatments. The TtgR protein of Pseudomonas putida is a HTH-type transcriptional repressor that controls expression of the TtgABC efflux pump, which is the main contributor to resistance against several antimicrobials and toxic compounds in this microbe. One of the main strategies to modulate the bacterial resistance is the rational modification of the ligand binding target site. We report the design and characterization of four mutants-TtgRS77A, TtgRE78A, TtgRN110A and TtgRH114A - at the active ligand binding site. The biophysical characterization of the mutants, in the presence and in the absence of different antimicrobials, revealed that TtgRN110A is the variant with highest thermal stability, under any of the experimental conditions tested. EMSA experiments also showed a different dissociation pattern from the operator for TtgRN110A, in the presence of several antimicrobials, making it a key residue in the TtgR protein repression mechanism of the TtgABC efflux pump. We found that TtgRE78A stability is the most affected upon effector binding. We also probe that one mutation at the C-terminal half of helix-α4, TtgRS77A, provokes a severe protein structure distortion, demonstrating the important role of this residue in the overall protein structure and on the ligand binding site. The data provide new information and deepen the understanding of the TtgR-effector binding mechanism and consequently the TtgABC efflux pump regulation mechanism in Pseudomonas putida.This work was supported by Spanish Ministry of Economy and Competitiveness, National programme for Recruitment and Incorporation of Human Resources, Subprogramme: Ramon y Cajal RYC-2009-04570 and grant P11-CVI-7391 from Junta de Andalucía and EFDR (European Regional Development Fund)

A Versatile ΦC31 Based Reporter System for Measuring AP-1 and Nrf2 Signaling in Drosophila and in Tissue Culture

This paper describes the construction and characterization of a system of transcriptional reporter genes for monitoring the activity of signaling pathways and gene regulation mechanisms in intact Drosophila, dissected tissues or cultured cells. Transgenic integration of the reporters into the Drosophila germline was performed in a site-directed manner, using ΦC31 integrase. This strategy avoids variable position effects and assures low base level activity and high signal responsiveness. Defined integration sites furthermore enable the experimenter to compare the activity of different reporters in one organism. The reporter constructs have a modular design to facilitate the combination of promoter elements (synthetic transcription factor binding sites or natural regulatory sequences), reporter genes (eGFP, or DsRed.T4), and genomic integration sites. The system was used to analyze and compare the activity and signal response profiles of two stress inducible transcription factors, AP-1 and Nrf2. To complement the transgenic reporter fly lines, tissue culture assays were developed in which the same synthetic ARE and TRE elements control the expression of firefly luciferase

Ultraviolet Extinction and Visible Transparency by Ivy Nanoparticles

Though much research has been conducted for nanoparticles, naturally occurring nanoparticles have not yet been well explored for their diverse properties and potential applications. This paper reports the optical absorption and scattering properties of nanoparticles secreted by English ivy. Both experimental and theoretical studies have been conducted. Strong ultraviolet extinction and excellent visible transparency are observed, compared to the inorganic TiO2 and ZnO nanoparticles at similar concentrations. The contributions of absorption and scattering to the total extinction are quantified by simulation of the Mie scattering theory

An Outbreak of Dengue Fever in St. Croix (US Virgin Islands), 2005

BACKGROUND: Periodic outbreaks of dengue fever occur in the United States Virgin Islands. In June 2005, an outbreak of dengue virus (DENV) serotype-2 with cases of dengue hemorrhagic fever (DHF) was detected in St. Croix, US Virgin Islands. The objective of this report is to describe this outbreak of DENV-2 and the findings of a case-control study examining risk factors for DHF. METHODOLOGY/PRINCIPAL FINDINGS: This is the largest dengue outbreak ever recorded in St. Croix, with 331 suspected dengue cases reported island-wide during 2005 (62.2 cases/10,000 population); 54% were hospitalized, 21% had at least one hemorrhagic manifestation, 28% had thrombocytopenia, 5% had DHF and 1 patient died. Eighty-nine laboratory-positive hospitalized patients were identified. Of these, there were 15 (17%) who met the WHO criteria for DHF (cases) and 74 (83%) who did not (controls). The only variable significantly associated with DHF on bivariate or multivariable analysis was age, with an adjusted odds ratio (95% confidence interval) of 1.033 (1.003,1.064). CONCLUSIONS/SIGNIFICANCE: During this outbreak of DENV-2, a high proportion of cases developed DHF and increasing age was significantly associated with DHF

A equipe de enfermagem e a comunicação com o paciente traqueostomizado

OBJETIVO: identificar as percepções da equipe de enfermagem acerca da importância da comunicação no cuidado ao paciente traqueostomizado, de modo a auxiliá-lo na sua recuperação. MÉTODOS: estudo de abordagem quantitativa e qualitativa. A amostra do estudo foi constituída por 51 integrantes da equipe de enfermagem (auxiliares de enfermagem, técnicos e enfermeiros), das Clínicas Médica Feminina e Masculina, Centro de Terapia Semi-Intensiva e Intensiva Adulto, e Neurocirurgia, de um hospital de ensino em Curitiba/PR. As informações foram coletadas por meio de questionário com questões fechadas e abertas. Na associação entre variáveis quantitativas foram considerados o teste Qui-Quadrado, valores de p < 0,05 indicaram significância estatística, os dados qualitativos foram submetidos à proposta de análise de conteúdo. RESULTADOS: os dados mostram que os participantes têm vivências variadas em sua área de atuação e constatam na sua prática cotidiana a necessidade e a importância da interação com o paciente traqueostomizado para sua recuperação. Os resultados apontam que os Auxiliares e Técnicos, desenvolvem mais orientações do que o enfermeiro (p=0,028). CONCLUSÃO: evidenciou-se no estudo que na impossibilidade de comunicação verbal pelo paciente, os participantes do estudo se utilizam de estratégias diferenciadas de comunicação, como gestos, sinalização e comunicação escrita

Effect of Acute Exposure to Moderate Altitude on Muscle Power: Hypobaric Hypoxia vs. Normobaric Hypoxia

When ascending to a higher altitude, changes in air density and oxygen levels affect the way in which explosive actions are executed. This study was designed to compare the effects of acute exposure to real or simulated moderate hypoxia on the dynamics of the force-velocity relationship observed in bench press exercise. Twenty-eight combat sports athletes were assigned to two groups and assessed on two separate occasions: G1 (n = 17) in conditions of normoxia (N1) and hypobaric hypoxia (HH) and G2 (n = 11) in conditions of normoxia (N2) and normobaric hypoxia (NH). Individual and complete force-velocity relationships in bench press were determined on each assessment day. For each exercise repetition, we obtained the mean and peak velocity and power shown by the athletes. Maximum power (Pmax) was recorded as the highest Pmean obtained across the complete force-velocity curve. Our findings indicate a significantly higher absolute load linked to Pmax (~3%) and maximal strength (1RM) (~6%) in G1 attributable to the climb to altitude (P<0.05). We also observed a stimulating effect of natural hypoxia on Pmean and Ppeak in the middle-high part of the curve (≥60 kg; P<0.01) and a 7.8% mean increase in barbell displacement velocity (P<0.001). No changes in any of the variables examined were observed in G2. According to these data, we can state that acute exposure to natural moderate altitude as opposed to simulated normobaric hypoxia leads to gains in 1RM, movement velocity and power during the execution of a force-velocity curve in bench press.This study has been supported by a Grant from the Ministry of education, culture and Sport of Spain, Reference 14/UPB10/07