469 research outputs found

    Fractal spectra in generalized Fibonacci one-dimensional magnonic quasicrystals

    Get PDF
    AbstractIn this work we carry out a theoretical analysis of the spectra of magnons in quasiperiodic magnonic crystals arranged in accordance with generalized Fibonacci sequences in the exchange regime, by using a model based on a transfer-matrix method together random-phase approximation (RPA). The generalized Fibonacci sequences are characterized by an irrational parameter σ(p,q), which rules the physical properties of the system. We discussed the magnonic fractal spectra for first three generalizations, i.e., silver, bronze and nickel mean. By varying the generation number, we have found that the fragmentation process of allowed bands makes possible the emergence of new allowed magnonic bulk bands in spectra regions that were magnonic band gaps before, such as which occurs in doped semiconductor devices. This interesting property arises in one-dimensional magnonic quasicrystals fabricated in accordance to quasiperiodic sequences, without the need to introduce some deferent atomic layer or defect in the system. We also make a qualitative and quantitative investigations on these magnonic spectra by analyzing the distribution and magnitude of allowed bulk bands in function of the generalized Fibonacci number Fn and as well as how they scale as a function of the number of generations of the sequences, respectively

    On the Potential of the Excluded Volume and Auto-Correlation as Neuromorphometric Descriptors

    Full text link
    This work investigates at what degree two neuromorphometric measurements, namely the autocorrelation and the excluded volume of a neuronal cell can influence the characterization and classification of such a type of cells. While the autocorrelation function presents good potential for quantifying the dendrite-dendrite connectivity of cells in mosaic tilings, the excluded volume, i.e. the amount of the surround space which is geometrically not accessible to an axon or dendrite, provides a complementary characterization of the cell connectivity. The potential of such approaches is illustrated with respect to real neuronal cells.Comment: 15 pages, 6 figure

    Aplicando uma nova versão brasileira do UPSIT no Brasil

    Get PDF
    Standardized olfactory tests are now available to quantitatively assess disorders of olfaction. A Brazilian-Portuguese version of the University of Pennsylvania Smell Identification Test (UPSIT) is currently being developed specifically for the Brazilian population. The most recent Brazilian-Portuguese version of the UPSIT (UPSIT-Br2) was administered to 88 Brazilian subjects who had no history of neurological or otorhinolaryngological disease. UPSIT-Br2 scores decreased with age, were lower in men than in women, and were lower in subjects with lower income. The degree to which the poorer performance of subjects with lower socio-economic status reflects lack of familiarity with test items is not known. Although this version of the UPSIT provides a sensitive and useful test of smell function for the Brazilian population, a revision of some test items is needed to achieve comparable norms to those found using the North American UPSIT in the United States.Testes padronizados já estão disponíveis para testagem do olfato e uma versão em Português esta sendo desenvolvida para o University of Pennsylvania Smell Identification Test (UPSIT), especificamente para a população brasileira. A versão mais recente deste teste (chamada UPSIT-Br2) foi aplicada a 88 sujeitos brasileiros que não tinham história de qualquer problema neurológico ou otorrinolaringológico. Compatível com dados prévios da literatura, a performance no UPSIT-Br2 decaiu com a idade e foi inferior no genero masculino. Os resultados foram mais baixos em participantes de menor nível sócio-econômico e a relação deste achado com a falta de familiaridade para com os itens do teste não é conhecida. Apesar desta versão do UPSIT poder ser útil para o teste da função olfativa da população brasileira, a revisão de alguns itens se faz necessária para alcançar valores comparáveis aos dados normativos norte-americanos.Reta Lila Weston Trust for Medical Researc

    Digestible lysine effects on gene expression by Japanese quails in the pre-laying phase

    Get PDF
    This study aimed to determine the effects of digestible lysine levels in the diets of Japanese quail (Coturnix coturnix japonica) on performance, blood parameters and the expression of insulin-like growth factor I, and growth hormone receptor (GHR), apolipoprotein A-I (APOA-I), acetyl-CoA-carboxylase (ACC), and fatty acid synthase (FAS) genes. A total of 288 seven-day-old female Japanese quails were randomly assigned to one of three diets that contained 0.8%, 1.10%, or 1.40% digestible lysine. The birds were slaughtered at 42 days old, and relative gene expression was evaluated in the liver by qRT-PCR using the 2-ΔCT method. Lysine supplementation had no effect on weight gain and feed conversion. Abdominal fat was lower in birds supplemented with 0.8% digestible lysine than those supplemented with 1.10% and 1.40%. Increased total cholesterol and triglycerides were elevated in quails that received supplementation of 1.10% digestible lysine compared with the other diets. High density lipoproteins were decreased in birds that received 0.8% digestible lysine. Quails fed with 1.40% digestible lysine had greater expression of GHR and APOA-I than quails fed diets with 0.8 and 1.10% (P <0.05). The greatest expressions of ACC and FAS were observed in the liver of quails fed with 0.8% digestible lysine. The current results suggest that lysine supplementation in the pre-laying phase allows birds to deposit muscle mass to reach the optimal conformation and body fatness that provides an energetic reserve for the productive phase by modulating the expression of genes related to growth and lipid metabolism. Keywords: Coturnix coturnix japonica, growth, growth hormone, lipid synthesis, lipid metabolis

    Synthesis, surface active and antimicrobial properties of new alkyl 2,6-dideoxy-L-arabino-hexopyranosides

    Get PDF
    Synthesis of alkyl 2,6-dideoxy-L-arabino-hexopyranosides was accomplished by the reaction of 1,5-anhydro-2,6-dideoxy-L-arabino-hex-1-enitol with fatty alcohols in dichloromethane, catalyzed by triphenylphosphine hydrobromide. Reaction with octanol and dodecanol gave the corresponding α-glycosides in 50% and 42% yield, the β-glycosides in 20% and 21% yield and the α-anomer of the Ferrier product in 10% and 9% yield, respectively.Deacetylation of the α-/β-glycosides with sodium methoxide in methanol afforded the amphiphilic L-arabino-hexopyranosides in 94–99% yield. The surface tension at the air–water interface of the octyl L-glycosides and of the dodecyl α-L-glycoside aqueous solutions at 35 °C was measured with a du Noüy ring tensiometer and surface properties such as critical micelle concentration (CMC), relative surface excess, molecular area at the interface and Gibbs micellization free energy were evaluated. The stereochemistry of the hexopyranoside ring in unimers and aggregates is correlated to the hydrophobicity and packing efficiency on the air–water interface. The antibacterial and antifungal activities of the surface-active glycosides were evaluated using the paper disk diffusion method. The dodecyl α-L-arabino-hexopyranoside was quite active over Bacillus cereus and Bacillus subtilis, while low activity was found for this glycoside over Enterococcus faecalis and Listeria monocytogenes. The octyl glycosides tested showed low activity over almost all the above-mentioned bacteria, and also over the fungus Candida albicans. No inhibition of Salmonella enteritidis and of the filamentous fungus Aspergillus niger was detected for any of the compounds tested.info:eu-repo/semantics/publishedVersio

    Analysis Of The Ergosterol Biosynthesis Pathway Cloning, Molecular Characterization And Phylogeny Of Lanosterol 14 α-demethylase (erg11) Gene Of Moniliophthora Perniciosa

    Get PDF
    The phytopathogenic fungus Moniliophthora perniciosa (Stahel) Aime & Philips-Mora, causal agent of witches’ broom disease of cocoa, causes countless damage to cocoa production in Brazil. Molecular studies have attempted to identify genes that play important roles in fungal survival and virulence. In this study, sequences deposited in the M. perniciosa Genome Sequencing Project database were analyzed to identify potential biological targets. For the first time, the ergosterol biosynthetic pathway in M. perniciosa was studied and the lanosterol 14α-demethylase gene (ERG11) that encodes the main enzyme of this pathway and is a target for fungicides was cloned, characterized molecularly and its phylogeny analyzed.ERG11 genomic DNA and cDNA were characterized and sequence analysis of the ERG11 protein identified highly conserved domains typical of this enzyme, such as SRS1, SRS4, EXXR and the heme-binding region (HBR). Comparison of the protein sequences and phylogenetic analysis revealed that the M. perniciosa enzyme was most closely related to that of Coprinopsis cinerea.374683693Aime, M.C., Phillips-Mora, W., The causal agents of witches’ broom and frost pod rot of cacao (chocolate, Theobroma cacao) from a new lineage of Marasmiaceae (2005) Mycologia, 97, pp. 1012-1022Albertini, C., Thebaud, G., Fournier, E., Leroux, P., Eburicol 14α-demethylase gene (CYP51) polymorphism and speciation in Botrytis cinerea (2002) Mycol Res, 106, pp. 1171-1178Altschul, S.F., Gish, W., Miller, W., Myersewand Lipman, D.J., Basic local alignment search tool (1990) J Mol Biol, 215, pp. 403-410Bak, S., Kahn, R.A., Oisen, C.E., Halkier, B.A., Cloning and expression in Escherichia coli of the obtusifoliol 14α-demethylase of Sorghum bicolor (L.) Moench, a cytochrome P450 orthologous to the sterol 14α demethylases (CYP51) from fungi and mammals (1997) Plant J, 11, pp. 191-201Barrett-Bee, K., Dixon, G., Ergosterol biosynthesis inhibition: A target for antifungal agents (1995) Acta Biochim Pol, 42, pp. 465-480Bellamine, A., Mangla, A.T., Nes, W.D., Waterman, M.R., Characterization and catalytic properties of the sterol 14α-demethylase from Mycobacterium tuberculosis (1999) Proc Natl Acad Sci USA, 96, pp. 8937-8942Butler, G., Rasmussen, M.D., Lin, M.F., Santos, M.A., Sakthikumar, S., Munro, C.A., Rheinbay, E., Reedy, J.L., Evolution of pathogenicity and sexual reproduction in eight Candida genomes (2009) Nature, 459, pp. 657-662Carrillo-Muñoz, A.J., Giusiano, G., Ezkurra, P.A., Quindós, G., Antifungal agents: Mode of action in yeast cells (2006) Rev Esp Quim, 19, pp. 130-139Ceita, G.O., Macedo, J.N., Santos, T.B., Alemanno, L., Gesteira, A.S., Micheli, F., Mariano, A.C., Meinhardt, L.W., Involvement of calcium oxalate degradation during programmed cell death in Theobroma cacao tissues triggered by the hemibiotrophic fungus Moniliophthora perniciosa (2007) Plant Sci, 173, pp. 106-117D’souza, C.A., Kronstad, J.W., Taylor, G., Warren, R., Yuen, M., Hu, G., Jung, W.H., Tangen, K., Genome variation in Cryptococcus gattii, an emerging pathogen of immunocompetent hosts (2011) MBio, 2, pp. e00342-e00410Délye, C., Laigret, F., Corio-Costet, M.F., Cloning and sequence analysis of the eburicol 14α-demethylase gene of the obligate biotrophic grape powdery mildew fungus (1997) Gene, 195, pp. 29-33Dujon, B., Sherman, D., Fischer, G., Durrens, P., Casaregola, S., Lafontaine, I., De Montigny, J., Talla, E., Genome evolution in yeasts (2004) Nature, 430, pp. 35-44Evans, H.C., Cacao diseases - The trilogy revisited (2007) Phytopathology, 97, pp. 1640-1643Felsenstein, J., Confidence limits on phylogenies: An approach using the bootstrap (1985) Evolution, 39, pp. 783-791Formighieri, E.F., Tiburcio, R.A., Armas, E.D., Medrano, F.J., Shimo, H., Carels, N., GóEs Neto, A., Sardinha-Pinto, N., The mitochondrial genome of the phytopathogenic basidiomycete Moniliophthora perniciosa is 109 kb in size and contains a stable integrated plasmid (2008) Mycol Res, 112, pp. 1136-1152Gasteiger, E., Hoogland, C., Gattiker, A., Duvaud, S., Wilkins, M.R., Appel, R.D., Bairoch, A., Protein identification and analysis tools on the ExPASy Server (2005) The Proteomics and Protocols Handbook, pp. 571-607. , In: Walker JM, Humana Press, TotowaGoffeau, A., Barrell, B.G., Bussey, H., Davis, R.W., Dujon, B., Feldmann, H., Galibert, F., Johnston, M., Life with 6000 genes (1996) Science, 265, pp. 2077-2082Griffith, G.W., Bravo-Velasquez, E., Wilson, F.J., Lewis, D.M., Hedger, J.N., Autecology and evolution of the witches’ broom pathogen (Crinipellis perniciosa) of cocoa (1994) The Ecology of Plant Pathogens, pp. 245-265. , In: Blakeman JP and Williamson B, CAB International, WallingfordGriffith, G.W., Nicholson, J., Neinninger, A., Birch, R., Witches’ brooms and frosty pods: Two major pathogens of cacao (2003) New Zeal J Bot, 41, pp. 423-435Hall, T.A., BioEdit: A user-friendly biological sequence alignment editor and analysis program for Windows 95/98/NT (1999) Nucleic Acids Res, 41, pp. 95-98Hof, H., Critical annotations to the use of azole antifungals for plant protection (2001) Antimicrob Agents Chemother, 45, pp. 2987-2990Jackson, C.J., Lamb, D.C., Marczylo, T.H., Parker, J.E., Manning, N.L., Kelly, D.E., Kelly, S.L., Conservation and cloning of CYP51: A sterol 14α-demethylase from Mycobacterium smegmatis (2003) Biochem Biophys Res Commun, 301, pp. 558-563James, T.Y., Kauff, F., Schoch, C.L., Matheny, P.B., Hofstetter, V., Cox, C.J., Celio, G., Miadlikowska, J., Reconstructing the early evolution of Fungi using a six-gene phylogeny (2006) Nature, 19, pp. 818-822Jones, T., Federspiel, N.A., Chibana, H., Dungan, J., Kalman, S., Magee, B.B., Newport, G., Magee, P.T., The diploid genome sequence of Candida albicans (2004) Proc Natl Acad Sci USA, 101, pp. 7329-7334Kairuz, P.B., Zuber, J.P., Jaunin, P., Buchman, T.G., Bille, J., Rossier, M., Rapid detection and identification of Candida albicans and Torulopsis (Candida) glabrata in clinical specimens by species-specific nested PCR amplification of a cytochrome P-450 lanosterol-α-demethylase (L1A1) gene fragment (1994) J Clin Microbiol, 32, pp. 1902-1907Kalb, V.F., Woods, C.W., Turi, T.G., Dey, C.R., Sutter, T.R., Loper, J.C., Primary structure of the P450 lanosterol demethylase gene from Saccharomyces cerevisiae (1987) DNA, 6, pp. 529-537Kall, L., Krogh, A., Sonnhammer, E.L., Advantages of combined transmembrane topology and signal peptide prediction- the Phobius web server (2007) Nucleic Acids Res 35:429-, p. 432Kim, D., Lim, Y.R., Ohk, S.O., Kim, B.J., Chun, Y.J., Functional expression and characterization of CYP51 from dandruffcausing Malassezia globosa (2011) FEMS Yeast Res, 11, pp. 80-87Lai, M.H., Kirsch, D.R., Nucleotide sequence of cytochrome P450 L1A1 (lanosterol 14α-demethylase) from Candida albicans (1989) Nucleic Acids Res, 17, p. 804Lamb, D.C., Kelly, D.E., Manning, N.M., Hollomon, D.W., Kelly, S.L., Expression, purification, reconstitution and inhibition of Ustilago maydis sterol 14α-demethylase (CYP 51P450) (1998) FEMS Microbiol Lett, 169, pp. 369-373Lee, C.H., Hsu, K.H., Wang, S.Y., Chang, T.T., Chu, F.H., Shaw, J.F., Cloning and characterization of the lanosterol 14α-demethylase gene from Antrodia cinnamomea (2010) J Agr Food Chem, 58, pp. 4800-4807Lees, N.D., Skaggs, B., Kirsch DR and BirdM(1995) Cloning of the late genes in the ergosterol biosynthetic pathway of Saccharomyces cerevisiae - A review Lipids, 30, pp. 221-226Lepesheva, G.I., Waterman, M.R., Sterol 14α-demethylase cytochrome P450 (CYP51), a P450 in all biological kingdoms (2007) Biochim Biophys Acta, 3, pp. 467-477Luo, C.X., Schnabel, G., The cytochrome P450 lanosterol 14α-demethylase gene is a demethylation inhibitor fungicide resistance determinant in Monilia fructicola field isolates from Georgia (2008) Appl Environ Microb, 74, pp. 359-366Martin, F., Aerts, A., Ahrén, D., Brun, A., Danchin, E.G., Duchaussoy, F., Gibon, J., Pereda, V., The genome of Laccaria bicolor provides insights into mycorrhizal symbiosis (2008) Nature, 452, pp. 88-92McQuilken, M.P., Rudgard, S.A., Sensitivity of Crinipellis periciosa to two triazole fungicides in vitro and their effect on development of the fungus in cocoa (1988) Plant Pathol, 37, pp. 499-506Meinhardt, L.W., Bellato, C.M., Rincones, J., Azevedo, R.A., Cascardo, J.C.M., Pereira, G.A.G., In vitro production of biotrophic- like cultures of Crinipellis perniciosa, the causal agent of Witches’ broom disease of Theobroma cacao (2006) Curr Microbiol, 52, pp. 191-196Mellado, E., Guerra, T.M.D., Estrela, M.C., Tudela, J.L.R., Identification of two different 14α-sterol demethylase related genes (cyp51A and cyp51B) in Aspergillus fumigatus and other Aspergillus species (2001) J Clin Microbiol 39:2431-, p. 2438Mondego, J.M.C., Carazzolle, M.F., Costa, G.G.L., Formighieri, E.F., Parizzi, L.P., Rincones, J., Cotomacci, C., Carrer, H., A genome survey of Moniliophthora perniciosa gives new insights into Witches’ broom disease of cacao (2008) BMC Genomics, 9, pp. 1-25Morales, I.J., Vohra, P.K., Puri, V., Kottom, T.J., Limper, A.H., Thomas, C.F., Characterization of a lanosterol 14α demethylase from Pneumocystis carinii (2003) Am J Resp Cell Mol, 29, pp. 232-238Mota, S.G.R., Barros, T.F., Castilho, M.S., In vitro screening and chemometrics analysis on a series of azole derivativeswith fungicide activity against Moniliophthora perniciosa (2010) J Braz Chem Soc, 21, pp. 510-519Nierman, W.C., Pain, A., Anderson, M.J., Wortman, J.R., Kim, H.S., Arroyo, J., Berriman, M., Bermejo, C., Genomic sequence of the pathogenic and allergenic filamentous fungus Aspergillus fumigatus (2005) Nature, 438, pp. 1151-1156Page, R.D.M., TREEVIEW: An application to display phylogenetic trees on personal computers (1996) Comput Appl Biosci, 12, pp. 357-358Park, H.G., Lee, I.S., Chun, Y.J., Yun, C.H., Johnston, J.B., Montellano, P.R.O., Kim, D., Heterologous expression and characterization of the sterol 14α-demethylase CYP51F from Candida albicans (2011) Arch Biochem Biophys, 509, pp. 9-15Pereira, J.L., Ram, A., Figueiredo, J.M., Almeida, L.C.C., Primeira ocorrência de vassoura-de-bruxa na principal região produtora de cacau do Brasil (1989) Agrotrópica, 1, pp. 79-81Petersen, T.N., Brunak, S., Heijne, G., Nielsen, H., SignalIP 4.0: Discriminating signal peptides from transmembrane regions (2011) Nat Methods, 10, pp. 785-786Pietila, M.P., Vohra, P.K., Sanyat, B., Wengenack, N.L., Raghavakaimal, S., Thomas, C.F., Cloning and characterization of CYP51 from Mycobacterium avium (2006) Am J Resp Cell Mol, 35, pp. 236-240Pires, A.B.L., Gramacho, K.P., Silva, D.C., Góes-Neto, A., Silva, M.M., Muniz-Sobrinho, J.S., Porto, R.F., Cascardo, J.C.M., Early development of Moniliophthora perniciosa basidiomata and developmentally regulated genes (2009) BMC Microbiol, 9, p. e158Purdy, L.H., Schimidt, R.A., Status of cacao witches’ broom: Biology, epidemiology, and management (1996) Annu Rev Phytopathol, 34, pp. 573-594Raeder, U., Broda, P., Rapid preparation of DNA from filamentous fungi (1985) Lett Appl Microbiol, 1, pp. 17-20Revankar, S.G., Fu, J., Rinaldi, M.G., Kelly, S.L., Kelly, D.E., Lamb, D.C., Keller, S.M., Wickes, B.L., Cloning and characterization of the lanosterol 14α-demethylase (ERG11) gene in Cryptococcus neoformans (2004) Biochem Biophys Res Commun, 324, pp. 719-728Rincones, J., Scarpari, L.M., Carazzolle, M.F., Mondego, J.M.C., Formighieri, E.F., Barau, J.G., Costa, G.G.L., Vilas-Boas, L.A., Differential gene expression between the biotrophic-like and saprotrophic mycelia of the witches’ broom pathogen Moniliophthora perniciosa (2008) Mol Plant Microbe Int, 21, pp. 891-908Rio, M.C.S., Oliveira, B.V., Tomazella, D.P.T., Silva, J.A.F., Pereira, G.A.G., Production of calcium oxalate crystals by the basidiomycete Moniliophthora perniciosa, the causal agent of witches’ broom disease of cacao (2008) Curr Microbiol, 56, pp. 363-370Rozman, D., Stromstedt, M., Tsui, L.C., Scherer, S.W., Waterman, M.R., Structure and mapping of the human lanosterol 14α-demethylase gene (CYP51) encoding the cytochrome P450 involved in cholesterol biosynthesis: Comparison of exon/intron organization with other mammalian and fungal CYP genes (1996) Genomics, 38, pp. 371-381Sheng, C., Miao, Z., Ji, H., Yao, J., Wang, W., Che, X., Dong, G., Zhang, W., Three-dimensional model of lanosterol 14α-demethylase from Cryptococcus neoformans: Active- site characterization and insights into azole binding (2009) Antimicrob Agents Chemother, 53, pp. 3487-3495Sigrist, C.J.A., Cerutti, L., Castro, E., Langendijk-Genevaux, P.S., Bulliard, V., Bairoch, A., Hulo, N., PROSITE, a protein domain database for functional characterization and annotation (2009) Nucleic Acids Res, 38, pp. 161-166Stajich, J.E., Wilke, S.K., Ahrén, D., Au, C.H., Birren, B.W., Borodovsky, M., Burns, C., Cheng, C.K., Insights into evolution of multicellular fungi from the assembled chromosomes of the mushroom Coprinopsis cinerea (Coprinus cinereus) (2010) Proc Natl Acad Sci USA, 107, pp. 11889-11894Stanke, M., Keller, O., Gunduz, I., Hayes, A., Waack, S., Morgenstern, B., AUGUSTUS: Ab initio prediction of alternative transcripts (2006) Nucleic Acids Res, 34, pp. 435-439Swofford, D.L., PAUP - Phylogenetic Analysis Using Parsimony (and other methods). Version 4.0b10 (2002) Sinauer Associates, , Sunderland, MATer-Hovhannisyan, V., Lomsadze, L., Chernoff, Y.O., Borodovsky, M., Gene prediction in novel fungal genomes using an ab initio algorithm with unsupervised training (2008) Genome Res, 18, pp. 1979-1990Thompson, J.D., Higgins, D.G., Gibson, T.J., CLUSTAL W: Improving the sensitivity of progressive multiple sequence alignment through sequence weighting, position specific gap penalties and weigh matrix choice (1994) Nucleic Acids Res, 22, pp. 4673-4680Veen, M., Lang, C., Interactions of the ergosterol biosynthetic pathway with other lipid pathways (2005) Biochem Soc Trans, 33, pp. 1178-1181Warrilow, A.G.S., Melo, N., Martel, C.M., Parker, J.E., Nes, W.D., Kelly, S.L., Kelly, D.E., Expression, purification and characterization of Aspergillus fumigatus sterol 14α demethylase (CYP51) isoenzymes A and B (2010) Antimicrob Agents Chemother, 54, pp. 4225-4234Waterman, M.R., Lepesheva, G.I., Sterol 14 _-demethylase, an abundant and essential mixed-function oxidase (2005) Biochem Biophys Res Commun, 338, pp. 418-422Wood, H.M., Dickinson, M.J., Lucas, J.A., Dyer, P.S., Cloning of the CYP51 gene from the eyespot pathogen Tapesia yallundae indicates that resistance to the DMI fungicide prochloraz is not related to sequence changes in the gene encoding the target site enzyme (2001) FEMS Microbiol Lett, 196, pp. 183-187Zhao, L., Liu, D., Zhang, Q., Zhang, S., Wan J and XiaoW(2007) Expression and homology modeling of sterol 14α-demethylase from Penicillium digitatium FEMS Microbiol Lett, 277, pp. 37-4
    • …
    corecore