Pimenta pseudocaryophyllus inhibits virulence factors and promotes metabolic changes in Candidayeast

IntroductionThis is the first study to examine the in vitrosusceptibility and the expression of virulence factors in Candida species in the presence of Pimenta pseudocaryophyllus (Gomes) L.R. Landrum (Myrtaceae), a Brazilian plant known as paucravo. Additionally, the mechanisms of action of the crude ethanol extract and the ethyl acetate and aqueous fractions of this plant were investigated.MethodsThe in vitro susceptibility of Candida was tested using the broth microdilution method, whereas an XTT reduction assay was used for biofilms. Adherence was determined by counting the number of yeast cells that adhered to 100 oral epithelial cells, and hyphal formation was verified in the hyphal induction medium M199. Flow cytometry with propidium iodide and FUN-1 was performed to assess the mechanism of action.ResultsThe results revealed that the crude ethanol extract and the ethyl acetate and aqueous fractions of P. pseudocaryophyllusinhibited the growth of Candida isolates at a minimal inhibitory concentration (MIC) ranging from 64 to 256µg/mL, whereas the 50% sessile minimal inhibitory concentration (SMIC50) ranged from 512 to >1,024µg/mL. Adherence and hyphal formation were significantly reduced in the presence of the crude ethanol extract and both fractions. Although cell membrane injury was detected, the predominant mechanism of action appeared to be the alteration of yeast metabolism, as demonstrated by flow cytometry.ConclusionsOur results indicated that antifungal activity reduced the expression of virulence factors in yeast via the alteration of yeast metabolism, suggesting that the crude extract of P. pseudocaryophyllus and its fractions may contain novel antifungal agents.

Nanocomposite polymer beads for cell detection

Circulating tumor cells (CTCs) may induce metastases when detached from the primary tumor. The numbers of these cells in blood offers a valuable prognostic indication. Magnetoresistive sensing is an attractive option for CTC counting. In this technique, cells are labeled with nancomposite polymer beads that provide the magnetic signal. Bead properties such as size and magnetic content must be optimized in order to be used as a detection tool in a magnetoresistive platform. Another important component of the platform is the magnet required for proper sensing. Both components are addressed in this work. Nanocomposite polymer beads were produced by nano-emulsion and membrane emulsification. Formulations of the oil phase comprising a mixture of aromatic monomers and iron oxide were employed. The effect of emulsifier (surfactant) concentration on bead size was studied. Formulations of polydimethilsiloxane (PDMS) with different viscosities were also prepared with nano-emulsion method resulting in colloidal beads. Polycaprolactone (PCL) beads were also synthetized by the membrane emulsification method. The beads were characterized by different techiques such as dynamic light scattering (DLS), thermogravimetric analysis (TGA) and scanning electron microscopy (SEM). Additionally, the magnet dimensions of the platform designed to detect CTCs were optimized through a COMSOL multiphysics simulation.

Life cycle of Trypanosoma cruzi (y strain) in mice

Since 1958, we have studied experimental Chagas' disease (CD) by subcutaneous inoculation of 1,000 blood forms of Trypanosoma cruzi (Y strain) in Balb/C. mice. Evolution of parasitemia remained constant, beginning on the 5th and 6th day of the disease, increasing progressively, achieving a maximum on about the 30th day. After another month, only a few forms were present, and they disappeared from the circulation after the third month, as determined from direct examination of slides and the use of a Neubauer Counting Chamber. These events coincided with the appearance of amastigote nests in the tissues (especially the cardiac ones), starting the first week, and following the Gauss parasitemia curve, but they were not in parallel until the chronic stage. In 1997, we began to note the following changes: Parasites appeared in the circulation during the first week and disappeared starting on the 7th day, and there was a coincident absence of the amastigote nests in the tissues. A careful study verified that young forms in the evolutionary cycle of T. cruzi (epi + amastigotes) began to appear alongside the trypomastigotes in the circulation on the 5th and 7th post-inoculation day. At the same time, rounded, oval, and spindle shapes were seen circulating through the capillaries and sinusoids of the tissues, principally of the hematopoietic organs. Stasis occurs because the diameter of the circulating parasites is greater than the vessels, and this makes them more visible. Examination of the sternal bone marrow revealed young cells with elongated forms and others truncated in the shape of a "C" occupying the internal surface of the blood cells that had empty central portions (erythrocytes?). We hypothesize that there could be a loss of virulence or mutation of the Y strain of Trypanosoma cruzi.

Introducing mapping standards in the quality assessment of buildings extracted from very high resolution satellite imagery

Many municipal activities require updated large-scale maps that include both topographic and thematic information. For this purpose, the efficient use of very high spatial resolution (VHR) satellite imagery suggests the development of approaches that enable a timely discrimination, counting and delineation of urban elements according to legal technical specifications and quality standards. Therefore, the nature of this data source and expanding range of applications calls for objective methods and quantitative metrics to assess the quality of the extracted information which go beyond traditional thematic accuracy alone. The present work concerns the development and testing of a new approach for using technical mapping standards in the quality assessment of buildings automatically extracted from VHR satellite imagery. Feature extraction software was employed to map buildings present in a pansharpened QuickBird image of Lisbon. Quality assessment was exhaustive and involved comparisons of extracted features against a reference data set, introducing cartographic constraints from scales 1:1000, 1:5000, and 1:10,000. The spatial data quality elements subject to evaluation were: thematic (attribute) accuracy, completeness, and geometric quality assessed based on planimetric deviation from the reference map. Tests were developed and metrics analyzed considering thresholds and standards for the large mapping scales most frequently used by municipalities. Results show that values for completeness varied with mapping scales and were only slightly superior for scale 1:10,000. Concerning the geometric quality, a large percentage of extracted features met the strict topographic standards of planimetric deviation for scale 1:10,000, while no buildings were compliant with the specification for scale 1:1000.

Search for massive supersymmetric particles decaying to many jets using the ATLAS detector in pp collisions at s√=8TeV

Results of a search for decays of massive particles to fully hadronic final states are presented. This search uses 20.3 fb−1 of data collected by the ATLAS detector in s√=8TeV proton--proton collisions at the LHC. Signatures based on high jet multiplicities without requirements on the missing transverse momentum are used to search for R-parity-violating supersymmetric gluino pair production with subsequent decays to quarks. The analysis is performed using a requirement on the number of jets, in combination with separate requirements on the number of b-tagged jets, as well as a topological observable formed from the scalar sum of the mass values of large-radius jets in the event. Results are interpreted in the context of all possible branching ratios of direct gluino decays to various quark flavors. No significant deviation is observed from the expected Standard Model backgrounds estimated using jet-counting as well as data-driven templates of the total-jet-mass spectra. Gluino pair decays to ten or more quarks via intermediate neutralinos are excluded for a gluino with mass mg~<1TeV for a neutralino mass mχ~01=500GeV. Direct gluino decays to six quarks are excluded for mg~<917GeV for light-flavor final states, and results for various flavor hypotheses are presented.

Relacionamentos em MMORPGs: online e offline

Dissertação de mestrado em Comunicação, Arte e Cultura

Monitorização do risco de dificuldades de aprendizagem específicas na leitura de alunos do 2.º ao 4.ºano no contexto do modelo de resposta à intervenção

Dissertação de mestrado em Educação Especial (área de especialização em Dificuldades de Aprendizagem Específicas)

Influence of oxygen conditions on bacterial interactions within biofilms related with cystic fibrosis

Dissertação de mestrado em Bioengineering

Contribuição para o melhoramento da gestão operacional de uma linha de fabrico de garrafas de gás

Dissertação de mestrado integrado em Engenharia e Gestão Industrial

Characterization of microbial populations in a wastewater treatment plant focusing on Staphylococcus aureus and Pseudomonas aeruginosa

Dissertação de mestrado em Bioengenharia

Procesos fotofísicos y fotoquímicos en sistemas organizados

Se estudiará el comportamiento de moléculas sonda aromáticas flourescentes en micelas inversas de AOT y BHDC y en soluciones de polielectrolitos y mezclas de polielectrolitos y detergentes. Se espera obtener información sobre la estructura de los sistemas microheterogéneos y cómo esta estructura afecta la formación de iones radicales obtenidos a partir de reacciones entre moléculas sonda y moléculas donoras o aceptoras de electrones. Las técnicas a emplear incluyen espectroscopía de absorción y emisión, láser flash fotólisis, flourescencia pulsada por láseres y time correlated single photon counting. Objetivos generales y específicos: 1. Fotofísica y fotoquímica en micelas inversas. 1.1. Exciplejos en micelas inversas. 1.2. Rendimientos de estados electrónicos triplete en micelas inversas. 1.3. Comportamiento de ftalocianinas y porfirinas en micelas inversas. 2. Soluciones de polielectrolitos y mezclas de polielectrolitos con detergentes. 2.1. Reacciones fotoinducidas. 2.2. Comportamiento de derivados de porfirinas y ftalocianinas. 3. Montaje de la técnica de Time Correlated Single Photn Counting. 4. Montaje de un equipo adicional de laser flash fotólisis. 5. Síntesis de derivados solubles en agua de porfirinas y ftalocianinas.

Disposición plasmática y residuos tisulares de marbofloxacina en truchas arco iris (oncorhynchus mykiss) en condiciones estivales e invernales. Plasmatic disposition and tissue residues of marbofloxacin in rainbow trouts (oncorhynchus mykiss) in summer and winter conditions

Los sistemas intensivos de producción, predisponen en los peces a la presentación de diversas enfermedades, lo que demanda el empleo de antimicrobianos para mantener la salud de los lotes de cultivo. En tal sentido es importante contar con información local en cuanto al comportamiento cinético a los efectos de determinar una adecuada dosificación de los antimicrobianos empleados y con esta información, establecer los periodos de resguardo necesarios para evitar la presencia violativa de estos fármacos en el animal destinado a consumo humano. En el presente proyecto se propone efectuar un estudio farmacocinético de concentraciones plasmáticas y tisulares alcanzadas y establecer los periodos de resguardo para marbofloxacina, antimicrobiano del cual no se tienen antecedentes regionales en cuanto a su disposición a diferentes temperaturas como las que condicionan las estaciones de verano e invierno, de marcada variación en la provincia, modificando la actividad metabólica de los peces. La concreción de este proyecto permitirá entregar conocimientos concretos y de aplicación directa en la cría intensiva de la trucha arco iris (Oncorhynchus mykiss) en diferentes condiciones ambientales, al contarse con la información necesaria para una adecuada dosificación y periodos de resguardo necesarios para evitar el residuo de este fármaco. Además, permitirá consolidar una línea de investigación dentro de la acuicultura muy poco desarrollada actualmente en el país. Intensive production systems predispose fishes to diverse diseases, which demands antimicrobial use for health maintenance in the lots of culture. In such sense it is important to have local information of the kinetic behavior to determine a suitable dosing of the antimicrobials employed, and on this information, to establish withdrawal periods to avoid the violative presence of these drugs in animals for human consumption. The present project will carry out a pharmacokinetic study of plasmatic and tissue concentrations to establish the withdrawal period for marbofloxacin, being known that temperature, modify the metabolic activity of the fish, and there are no local antecedents of disposition at different temperatures in summer and winter for this antimicrobial. The concretion of this project will allow to give concrete knowledge of direct application in intensive production of rainbow trout (Oncorhynchus mykiss), in different environmental conditions, counting with the necessary information for a suitable dosification and withdrawal periods to avoid residues of this drug. In addition, it will allow to consolidate an investigation line in acuiculture, not much developed in our country.

Insights into molecular mechanisms regulating the activity of multidomain proteins in living cells using FRET-FLIM

FRET-FLIM, ENERGY TRANSFER, LIFETIME, DECAY ASSOCIATED SPECTRUM, DAS, KINASE, MAGUKS, SINGLE PHOTON COUNTING, PICOSECOND-TIME RESOLVED FLUORESCENCE SPECTROSCOPY, GFP, CFP, YFP, TOPAZ, NANOMETER, MICROSCOPY, LYMPHOCYTES, LCK, SAP97

Fractal Dimension in Quantifying Experimental-Pulmonary-Hypertension-Induced Cardiac Dysfunction in Rats

Abstract Background: Right-sided heart failure has high morbidity and mortality, and may be caused by pulmonary arterial hypertension. Fractal dimension is a differentiated and innovative method used in histological evaluations that allows the characterization of irregular and complex structures and the quantification of structural tissue changes. Objective: To assess the use of fractal dimension in cardiomyocytes of rats with monocrotaline-induced pulmonary arterial hypertension, in addition to providing histological and functional analysis. Methods: Male Wistar rats were divided into 2 groups: control (C; n = 8) and monocrotaline-induced pulmonary arterial hypertension (M; n = 8). Five weeks after pulmonary arterial hypertension induction with monocrotaline, echocardiography was performed and the animals were euthanized. The heart was dissected, the ventricles weighed to assess anatomical parameters, and histological slides were prepared and stained with hematoxylin/eosin for fractal dimension analysis, performed using box-counting method. Data normality was tested (Shapiro-Wilk test), and the groups were compared with non-paired Student t test or Mann Whitney test (p < 0.05). Results: Higher fractal dimension values were observed in group M as compared to group C (1.39 ± 0.05 vs. 1.37 ± 0.04; p < 0.05). Echocardiography showed lower pulmonary artery flow velocity, pulmonary acceleration time and ejection time values in group M, suggesting function worsening in those animals. Conclusion: The changes observed confirm pulmonary-arterial-hypertension-induced cardiac dysfunction, and point to fractal dimension as an effective method to evaluate cardiac morphological changes induced by ventricular dysfunction.

A ação dos gens gametofíticos com referência especial ao milho

1) The first part deals with the different processes which may complicate Mendelian segregation and which may be classified into three groups, according to BRIEGER (1937b) : a) Instability of genes, b) Abnormal segregation due to distur- bances during the meiotic divisions, c) obscured segregation, after a perfectly normal meiosis, caused by elimination or during the gonophase (gametophyte in higher plants), or during zygophase (sporophyte). Without entering into detail, it is emphasized that all the above mentioned complications in the segregation of some genes may be caused by the action of other genes. Thus in maize, the instability of the Al factor is observed only when the gene dt is presente in the homozygous conditions (RHOADES 1938). In another case, still under observation in Piracicaba, an instability is observed in Mirabilis with regard to two pairs of alleles both controlling flower color. Several cases are known, especially in corn, where recessive genes, when homozigous, affect the course of meiosis, causing asynapsis (asyndesis) (BEADLE AND MC CLINTOCK 1928, BEADLE 1930), sticky chromosomes (BEADLE 1932), supermunmerary divisions (BEADLE 1931). The most extreme case of an obscured segregatiou is represented by the action of the S factors in self stetrile plants. An additional proof of EAST AND MANGELSDORF (1925) genetic formula of self sterility has been contributed by the studies on Jinked factors in Nicotina (BRIEGER AND MANGELSDORF (1926) and Antirrhinum (BRIEGER 1930, 1935), In cases of a incomplete competition and selection between pollen tubes, studies of linked indicator-genes are indispensable in the genetic analysis, since it is impossible to analyse the factors for gametophyte competition by direct aproach. 2) The flower structure of corn is explained, and stated that the particularites of floral biology make maize an excellent object for the study of gametophyte factors. Since only one pollen tube per ovule may accomplish fertilization, the competition is always extremely strong, as compared with other species possessing multi-ovulate ovaries. The lenght of the silk permitts the study of pollen tube competitions over a varying distance. Finally the genetic analysis of grains characters (endosperm and aleoron) simpliflen the experimental work considerably, by allowing the accumulation of large numbers for statistical treatment. 3) The four methods for analyzing the naturing of pollen tube competition are discussed, following BRIEGER (1930). Of these the first three are: a) polinization with a small number of pollen grains, b) polinization at different times and c) cut- ting the style after the faster tubes have passe dand before the slower tubes have reached the point where the stigma will be cut. d) The fourth method, alteration of the distatice over which competition takes place, has been applied largely in corn. The basic conceptions underlying this process, are illustrated in Fig. 3. While BRINK (1925) and MANGELSDORF (1929) applied pollen at different levels on the silks, the remaining authors (JONES, 1922, MANGELSDORF 1929, BRIEGER, at al. 1938) have used a different process. The pollen was applied as usual, after removing the main part of the silks, but the ears were divided transversally into halves or quarters before counting. The experiments showed generally an increase in the intensity of competition when there was increase of the distance over which they had to travel. Only MANGELSDORF found an interesting exception. When the distance became extreme, the initially slower tubes seemed to become finally the faster ones. 4) Methods of genetic and statistical analysis are discussed, following chiefly BRIEGER (1937a and 1937b). A formula is given to determine the intensity of ellimination in three point experiments. 5) The few facts are cited which give some indication about the physiological mechanism of gametophyte competition. They are four in number a) the growth rate depends-only on the action of gametophyte factors; b) there is an interaction between the conductive tissue of the stigma or style and the pollen tubes, mainly in self-sterile plants; c) after self-pollination necrosis starts in the tissue of the stigma, in some orchids after F. MÜLLER (1867); d) in pollon mixtures there is an inhibitory interaction between two types of pollen and the female tissue; Gossypium according to BALLS (1911), KEARNEY 1923, 1928, KEARNEY AND HARRISON (1924). A more complete discussion is found in BRIEGER 1930). 6) A list of the gametophyte factors so far localized in corn is given. CHROMOSOME IV Ga 1 : MANGELSDORF AND JONES (1925), EMERSON 1934). Ga 4 : BRIEGER (1945b). Sp 1 : MANGELSDORF (1931), SINGLETON AND MANGELSDORF (1940), BRIEGER (1945a). CHROMOSOME V Ga 2 : BRIEGER (1937a). CHROMOSOME VI BRIEGER, TIDBURY AND TSENG (1938) found indications of a gametophyte factor altering the segregation of yellow endosperm y1. CHROMOSOME IX Ga 3 : BRIEGER, TIDBURY AND TSENG (1938). While the competition in these six cases is essentially determined by one pair of factors, the degree of elimination may be variable, as shown for Ga2 (BRIEGER, 1937), for Ga4 (BRIEGER 1945a) and for Spl (SINGLETON AND MANGELSDORF 1940, BRIEGER 1945b). The action of a gametophyte factor altering the segregation of waxy (perhaps Ga3) is increased by the presence of the sul factor which thus acts as a modifier (BRINCK AND BURNHAM 1927). A polyfactorial case of gametophyte competition has been found by JONES (1922) and analysed by DEMEREC (1929) in rice pop corn which rejects the pollen tubes of other types of corn. Preference for selfing or for brothers-sister mating and partial elimination of other pollen tubes has been described by BRIEGER (1936). 7) HARLAND'S (1943) very ingenious idea is discussed to use pollen tube factors in applied genetics in order to build up an obstacle to natural crossing as a consequence of the rapid pollen tube growth after selfing. Unfortunately, HARLAND could not obtain the experimental proof of the praticability of his idea, during his experiments on selection for minor modifiers for pollen tube grouth in cotton. In maize it should be possible to employ gametophyte factors to build up lines with preference for crossing, though the method should hardly be of any practical advantage.