Molecular approaches to malaria and Babesisosis diagnosis

The development of additional methods for detecting and identifuing Babesia and Plasmodium infections may be useful in disease monitoring, management and control efforts. To preliminarily evaluate sunthetic peptide-based serodiagnosis, a hydrophilic sequence (DDESEFDKEK)was selected from published BabR gene of B. bovis. Immunization of rabbits and cattle with the hemocyanin-conjugated peptide elicited antibody responses that specifically detected both P. falciparum and B. bovis antigens by immunofluorescence and Western blots. Using a dot-ELISA with this peptide, antisera from immunized and naturally-infected cattle, and immunized rodents, were specifically detected. Reactivity was weak and correlated with peptide immunization or infection. DNA-based detection using repetitive DNA was species-specific in dot-blot formats for B. bovis DNA, and in both dot-blot and in situ formats for P. falciparum; a streamlined enzymelinked synthetic DNA assay for P. falciparum detected 30 parasites/mm(cúbicos) from patient blood using either colorimetric (2-15 h color development) or chemiluminescent detection (0.5-6-min. exposures). Serodiagnostic and DNA hybridization methods may be complementary in the respective detection of both chronic and acute infections. However, recent improvements in the polymerase chain reaction (PCR) make feasible a more sensitive and uniform approach to the diagnosis of these and other infectious disease complexes, with appropriate primers and processing methods. An analysis of ribosomal DNA genes of Plasmodium and Toxoplasma identified Apicomplexa-conserved sequence regions. Specific and distinctive PCR profiles were obtained for primers spanning the internal transcribed spacer locus for each of several Plasmodium and Babesia species.

Differential lectin labelling of circulating hemocytes from Biomphalaria glabrata and Biomphalaria tenagophila resistant or susceptible to Schistosoma mansoni infection

Lectins/carbohydrate binding can be involved in the Schistosoma mansoni recognition and activation of the Biomphalaria hemocytes. Therefore, expression of lectin ligands on Biomphalaria hemocytes would be associated with snail resistance against S. mansoni infection. To test this hypothesis, circulating hemocytes were isolated from B. glabrata BH (snail strain highy susceptible to S. mansoni), B. tenagophila Cabo Frio (moderate susceptibility), and B. tenagophila Taim (completely resistant strains), labelled with FITC conjugated lectins (ConA, PNA, SBA, and WGA) and analyzed under fluorescence microscopy. The results demonstrated that although lectin-labelled hemocytes were detected in hemolymph of all snail species tested, circulating hemocytes from both strains of B. tenagophila showed a larger number of lectin-labelled cells than B. glabrata. Moreover, most of circulating hemocytes of B. tenagophila were intensively labelled by lectins PNA-FITC and WGA-FITC, while in B. glabrata small hemocytes were labeled mainly by ConA. Upon S. mansoni infection, lectin-labelled hemocytes almost disappeared from the hemolymph of Taim and accumulated in B. glabrata BH. The role of lectins/carbohydrate binding in resistance of B. tengophila infection to S. mansoni is still not fully understood, but the data suggest that there may be a correlation to its presence with susceptibility or resistance to the parasite.

Development of Schistosoma mansoni worms in mice analyzed by bright field and confocal microscopy

The blood flukes of mammals (Digenea: Schistosomatidae) are among trematodes unique whose adult worms have separeted sexes which are dissimilar in appearance. The developmental features, growth and organogenesis of Schistosoma mansoni were studied in Swiss Webster mice by a digital system for image analysis and confocal microscopy. Data so far obtained showed two phases with significative morphological changes at 3-4 weeks post-infection, and a gradual similar development onwards in the reproductive system and tegument. Our male-dependent phase demonstrated that mating occurs before sexual maturing. At week three, the majority of male worms (59%) had formed the gynaecophoric canal although testicular lobes and tegumental tubercles were absent. By this time, 33% females had an incipient ovary (without cellular differentiation). At week four, 77.2% males presented testicular lobes with few germinative cells while 26% had developing tegumental tubercles. The immature ovary was observed in 69% females. Suckers followed different pattern of growth between male and females. The size of oral and ventral suckers from six-week-old male worms grew abruptly (3.0 fold) more than that of three-week-old. In female worms, maximum growth was attained at week four, reducing in size thereafter. From sixth week onwards, all specimens showed the fully developed reproductive system. Probably, these features are morphological traits which schistosome has experienced from hermaphrodite to dioecy.

Offshore work and the work of nurses on board: an integrative review

OBJECTIVETo know the production of theoretical approaches on issues related to offshore work and the work of offshore nurses.METHODIntegrative literature review conducted in the databases of LILACS, BDENF, MEDLINE, SciELO and Index PSI.RESULTSWe selected 33 studies published in national and international journals between 1997 and 2014. The thematic analysis corpus resulted in four central themes: offshore work environment; amid work adversities, an escape; structuring of offshore health and safety services; in search of safe practices.CONCLUSIONThis study contributes to the offshore work of nurses in relation to the nature of work, acting amid adversities and the restless search for safe practices in the open sea.

Metabolic responses of guava trees irrigated withdifferent N and K levels in São Francisco Valley

The guava (Psidium guajava L.) cv. Paluma has been cultivated in São Francisco Valley, Northeastern of Brazil, for in natura consumption and processing purposes. In spite of its importance, there are few scientific knowledge regarding guava physiology, nutrition, irrigation and fertigation. The objective of this work was to evaluate the effect of weather conditions and different concentrations of N and K applied by fertigation in foliar contents of reducing sugars, total soluble sugars, starch, sucrose, amino acids, and proteins. The field experiment was carried out at Bebedouro Experimental Field and the biochemical evaluations at the Laboratory of Seed and Plant Physiology, both located at Embrapa Semi-Árido, Petrolina-PE. The doses of 200 g N and 100 g K2O; 400 g N and 200 g K2O; 600 g N and 300 g K2O; and 800 g N and 400 g K2O per plant were applied in an experiment field. The experimental design was totally randomized blocks, with four treatments and five blocks. The weather conditions influenced the plant photosynthesis, which affects the plants metabolism. Guava presented specific responses to N and K fertigation for each parameter evaluated. The weather conditions during the evaluation period influenced guava responses to N and K fertigation.

Hardcopy quality parameters to ensure structures detection at digital mammography

Objective To develop procedures to ensure consistency of printing quality of digital images, by means of hardcopy quantitative analysis based on a standard image. Materials and Methods Characteristics of mammography DI-ML and general purpose DI-HL films were studied through the QC-Test utilizing different processing techniques in a FujiFilm®-DryPix4000 printer. A software was developed for sensitometric evaluation, generating a digital image including a gray scale and a bar pattern to evaluate contrast and spatial resolution. Results Mammography films showed maximum optical density of 4.11 and general purpose films, 3.22. The digital image was developed with a 33-step wedge scale and a high-contrast bar pattern (1 to 30 lp/cm) for spatial resolution evaluation. Conclusion Mammographic films presented higher values for maximum optical density and contrast resolution as compared with general purpose films. The utilized digital processing technique could only change the image pixels matrix values and did not affect the printing standard. The proposed digital image standard allows greater control of the relationship between pixels values and optical density obtained in the analysis of films quality and printing systems.

Construction and application of a portable microcontrolled turbidimeter for the in situ determination of sulfate

This study reports on the construction of a turbidimeter employing light emitting diodes as radiation source at a wavelength of 405 nm, a photodiode as detector, a temperature sensor and a microcontroller used for data acquisition and processing. The turbidimeter was applied to determine sulfate concentrations in natural water employing barium chloride as reagent. Potential interferences and recovery studies were performed and an interference of 3.5 % and a recovery between 97.8 and 108 % were estimated. The analytical performance of in situ turbidimeter for the determination of sulfate was evaluated and compared with two commercial spectrophotometers and a good agreement was obtained.

Augmented reality systems for weed economic thresholds applications

The augmented reality (AR) technology has applications in many fields as diverse as aeronautics, tourism, medicine, and education. In this review are summarized the current status of AR and it is proposed a new application of it in weed science. The basic algorithmic elements for AR implementation are already available to develop applications in the area of weed economic thresholds. These include algorithms for image recognition to identify and quantify weeds by species and software for herbicide selection based on weed density. Likewise, all hardware necessary for AR implementation in weed science are available at an affordable price for the user. Thus, the authors propose weed science can take a leading role integrating AR systems into weed economic thresholds software, thus, providing better opportunities for science and computer-based weed control decisions.

Photodynamic DNA damage induced by phycocyanin and its repair in Saccharomyces cerevisiae

In the present study, we analyzed DNA damage induced by phycocyanin (PHY) in the presence of visible light (VL) using a set of repair endonucleases purified from Escherichia coli. We demonstrated that the profile of DNA damage induced by PHY is clearly different from that induced by molecules that exert deleterious effects on DNA involving solely singlet oxygen as reactive species. Most of PHY-induced lesions are single strand breaks and, to a lesser extent, base oxidized sites, which are recognized by Nth, Nfo and Fpg enzymes. High pressure liquid chromatography coupled to electrochemical detection revealed that PHY photosensitization did not induce 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodGuo) at detectable levels. DNA repair after PHY photosensitization was also investigated. Plasmid DNA damaged by PHY photosensitization was used to transform a series of Saccharomyces cerevisiae DNA repair mutants. The results revealed that plasmid survival was greatly reduced in rad14 mutants, while the ogg1 mutation did not modify the plasmid survival when compared to that in the wild type. Furthermore, plasmid survival in the ogg1 rad14 double mutant was not different from that in the rad14 single mutant. The results reported here indicate that lethal lesions induced by PHY plus VL are repaired differently by prokaryotic and eukaryotic cells. Morever, nucleotide excision repair seems to play a major role in the recognition and repair of these lesions in Saccharomyces cerevisiae.

Steps in the formation of neurites and synapses studied in cultured leech neurons

Leech neurons in culture have provided novel insights into the steps in the formation of neurite outgrowth patterns, target recognition and synapse formation. Identified adult neurons from the central nervous system of the leech can be removed individually and plated in culture under well-controlled conditions, where they retain their characteristic physiological properties, grow neurites and form specific chemical or electrical synapses. Different identified neurons develop distinctive outgrowth patterns that depend on their identities and on the molecular composition of the substrate. On native substrates, the patterns displayed by these neurons reproduce characteristics from the adult or the developing neurons. In addition, the substrate may induce selective directed growth between pairs of neurons that normally make contact in the ganglion. Upon contact, pairs of cultured leech neurons form chemical or electrical synapses, or both types depending on the neuronal identities. Anterograde and retrograde signals during membrane contact and synapse formation modify the distribution of synaptic terminals, calcium currents, and responses to 5-hydroxytryptamine.

The role of chemokines and chemokine receptors in eosinophil activation during inflammatory allergic reactions

Chemokines are important chemotactic cytokines that play a fundamental role in the trafficking of leukocytes to sites of inflammation. They are also potent cell-activating factors, inducing cytokine and histamine release and free radical production, a fact that makes them particularly important in the pathogenesis of allergic inflammation. The action of chemokines is regulated at the level of agonist production and processing as well as at the level of receptor expression and coupling. Therefore, an analysis of the ligands must necessarily consider receptors. Eosinophils are target cells involved in the allergic inflammatory response since they are able to release a wide variety of mediators including CC and CXC chemokines and express their receptors. These mediators could damage the airway epithelial cells and might be important to stimulate other cells inducing an amplification of the allergic response. This review focuses on recently emerging data pertaining to the importance of chemokines and chemokine receptors in promoting eosinophil activation and migration during the allergic inflammatory process. The analysis of the function of eosinophils and their chemokine receptors during allergic inflammation might be a good approach to understanding the determinants of asthma severity and to developing novel therapies.

A carbohydrate-based mechanism of species recognition in sea urchin fertilization

In the present review, we describe a systematic study of the sulfated polysaccharides from marine invertebrates, which led to the discovery of a carbohydrate-based mechanism of sperm-egg recognition during sea urchin fertilization. We have described unique polymers present in these organisms, especially sulfated fucose-rich compounds found in the egg jelly coat of sea urchins. The polysaccharides have simple, linear structures consisting of repeating units of oligosaccharides. They differ among the various species of sea urchins in specific patterns of sulfation and/or position of the glycosidic linkage within their repeating units. These polysaccharides show species specificity in inducing the acrosome reaction in sea urchin sperm, providing a clear-cut example of a signal transduction event regulated by sulfated polysaccharides. This distinct carbohydrate-mediated mechanism of sperm-egg recognition coexists with the bindin-protein system. Possibly, the genes involved in the biosynthesis of these sulfated fucans did not evolve in concordance with evolutionary distance but underwent a dramatic change near the tip of the Strongylocentrotid tree. Overall, we established a direct causal link between the molecular structure of a sulfated polysaccharide and a cellular physiological event - the induction of the sperm acrosome reaction in sea urchins. Small structural changes modulate an entire system of sperm-egg recognition and species-specific fertilization in sea urchins. We demonstrated that sulfated polysaccharides - in addition to their known function in cell proliferation, development, coagulation, and viral infection - mediate fertilization, and respond to evolutionary mechanisms that lead to species diversity.

Anxiety and depression symptoms in recurrent painful renal lithiasis colic

Several studies have reported that symptoms of anxiety and depression are significantly associated with diseases characterized by painful crises. However, there is little information about the psychological aspects of recurrent painful episodes of renal stone disease. Our objective was to evaluate the association of symptoms of anxiety, depression and recurrent painful renal colic in a case-control study involving 64 subjects (32 cases/32 controls) matched for age and sex. Cases were outpatients with a confirmed diagnosis of nephrolithiasis as per their case history, physical examination, image examination and other laboratory exams. Patients had a history of at least two episodes within a 3-year period, and were currently in an intercrisis interval. The control group consisted of subjects seen at the Ophthalmology Outpatient Clinic of this University Hospital with only eye refraction symptoms, and no other associated disease. Symptoms of anxiety were evaluated by the State-Trait Anxiety Inventory and symptoms of depression by the Beck Depression Inventory. Statistically significant differences were observed between patients with nephrolithiasis and controls for anxiety state (P = 0.001), anxiety trait (P = 0.005) and symptoms of depression (odds ratio = 3.74; 95%CI = 1.31-10.62). The Beck Depression Inventory showed 34.5% of respondents with moderate and 6% with severe levels of depression. There was a significant linear correlation between symptoms of anxiety (P = 0.002) and depression (P < 0.001) and the number of recurrent colic episodes (anxiety-state: P = 0.016 and anxiety-trait: P < 0.001). These data suggest an association between recurrent renal colic and symptoms of both anxiety and depression.

Effect of image resolution manipulation in rearfoot angle measurements obtained with photogrammetry

The aim of this study was to investigate the influence of image resolution manipulation on the photogrammetric measurement of the rearfoot static angle. The study design was that of a reliability study. We evaluated 19 healthy young adults (11 females and 8 males). The photographs were taken at 1536 pixels in the greatest dimension, resized into four different resolutions (1200, 768, 600, 384 pixels) and analyzed by three equally trained examiners on a 96-pixels per inch (ppi) screen. An experienced physiotherapist marked the anatomic landmarks of rearfoot static angles on two occasions within a 1-week interval. Three different examiners had marked angles on digital pictures. The systematic error and the smallest detectable difference were calculated from the angle values between the image resolutions and times of evaluation. Different resolutions were compared by analysis of variance. Inter- and intra-examiner reliability was calculated by intra-class correlation coefficients (ICC). The rearfoot static angles obtained by the examiners in each resolution were not different (P > 0.05); however, the higher the image resolution the better the inter-examiner reliability. The intra-examiner reliability (within a 1-week interval) was considered to be unacceptable for all image resolutions (ICC range: 0.08-0.52). The whole body image of an adult with a minimum size of 768 pixels analyzed on a 96-ppi screen can provide very good inter-examiner reliability for photogrammetric measurements of rearfoot static angles (ICC range: 0.85-0.92), although the intra-examiner reliability within each resolution was not acceptable. Therefore, this method is not a proper tool for follow-up evaluations of patients within a therapeutic protocol.

Evaluation of Toll-like, chemokine, and integrin receptors on monocytes and neutrophils from peripheral blood of septic patients and their correlation with clinical outcomes

Recognition of pathogens is performed by specific receptors in cells of the innate immune system, which may undergo modulation during the continuum of clinical manifestations of sepsis. Monocytes and neutrophils play a key role in host defense by sensing and destroying microorganisms. This study aimed to evaluate the expression of CD14 receptors on monocytes; CD66b and CXCR2 receptors on neutrophils; and TLR2, TLR4, TLR5, TLR9, and CD11b receptors on both cell types of septic patients. Seventy-seven septic patients (SP) and 40 healthy volunteers (HV) were included in the study, and blood samples were collected on day zero (D0) and after 7 days of therapy (D7). Evaluation of the cellular receptors was carried out by flow cytometry. Expression of CD14 on monocytes and of CD11b and CXCR2 on neutrophils from SP was lower than that from HV. Conversely, expression of TLR5 on monocytes and neutrophils was higher in SP compared with HV. Expression of TLR2 on the surface of neutrophils and that of TLR5 on monocytes and neutrophils of SP was lower at D7 than at D0. In addition, SP who survived showed reduced expression of TLR2 and TLR4 on the surface of neutrophils at D7 compared to D0. Expression of CXCR2 for surviving patients was higher at follow-up compared to baseline. We conclude that expression of recognition and cell signaling receptors is differentially regulated between SP and HV depending on the receptor being evaluated.