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61.
César Fernández-de-las-Pe?as Domingo Palacios-Ce?a Jaime Salom-Moreno Ana López-de-Andres Valentín Hernández-Barrera Isabel Jiménez-Trujillo Rodrigo Jiménez-García Carmen Gallardo-Pino María S. García-Gómez-de-las-Heras Pilar Carrasco-Garrido 《PloS one》2014,9(10)
Introduction
Information on temporal trends can identify groups of people at risk for any particular condition; however information on temporal trends on migraine headache at population levels is scarce. Our aim was to estimate the time trends in the prevalence of migraine from 2003 to 2012 in Spain.Methods
A population-based national study was conducted. We analyzed data using individualized information taken from national surveys conducted in 2003/4, 2006/7, 2009/10 and 2011/12. A total of 94,158 Spanish adults participated. We considered the presence of self-rated and diagnosed migraine, and we analyzed socio-demographic features, lifestyle habits, self-rated health status, and comorbid diseases using logistic regressions.Results
The prevalence of migraine increased from 6.54% in 2003 to 9.69% in 2012 with significant time trends (adj. OR 1.65; 95%CI 1.50–1.81). The probability of women of suffering migraine was 3 times higher than for men (adj.OR 3.08; 2.82–3.37). There was a declining trend in migraine prevalence as age increased (adj.OR 0.42; 0.35–0.51). Demographic variables associated with migraine were lower educational level (adj.OR 1.32; 1.13–1.54) and not being an immigrant (adj.OR 1.37; 1.15–1.64). A worse self-reported health status was related to higher prevalence of migraine (adj.OR 2.83; 2.59–3.09). The prevalence of migraine also increased as the number of comorbid conditions increased (adj.OR 2.42; 2.05–2.86).Conclusion
The prevalence of migraine has increased in the first decade of the 21st century in Spain. Migraine was associated with being female, mid-age, low educational level, not being an immigrant, worse self-rated health status and presence of comorbid conditions. 相似文献62.
63.
Balearic lizards use chemical cues from a complex deceptive mimicry to capture attracted pollinators
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Ana Pérez‐Cembranos Valentín Pérez‐Mellado William E. Cooper 《Ethology : formerly Zeitschrift fur Tierpsychologie》2018,124(4):260-268
Deceptive flowers from several plant species emit odors that mimic oviposition cues and attract female insects seeking for a laying site. Helicodiceros muscivorus is a species that emits an odor mimicking the foul smell of rotting meat and thereby attracts blowflies that usually oviposit on carcasses but are deceived into pollinating the plant. Thus, H. muscivorus is a striking case of pollination by brood‐site deception. The Balearic lizard, Podarcis lilfordi, exhibits remarkable interactions with dead horse arum. Balearic lizards, which sometimes forage on carcasses, are attracted to blooming dead horse arum. We showed experimentally that P. lilfordi can detect chemical cues from carcasses on cotton swabs and exhibits elevated tongue‐flick rates to carcass chemical cues compared to control stimuli. Lizards also detected and located hidden carcasses using only airborne chemical cues. The responses of lizards to chemical cues from the spadix of blooming dead horse arum were qualitatively and quantitatively similar to those to carcass odors. Therefore, the decay‐like odor that attracts blowflies for the plant's benefit also attracts lizards. This attraction may initially have been somewhat favorable for lizards that eat blowflies, but slightly unfavorable for plants because the lizards ate some pollinators. We suggest that lizards attracted by odor may have learned later to use the plant for thermoregulation and then consume its fruits, making the association more positive for lizards and benefitted arum by seed dispersal. 相似文献
64.
Quido A. Valent Jelle Zaal Frits K. de Graaf Bauke Oudega 《Molecular microbiology》1995,16(6):1243-1257
The subcellular localization of the K88 usher FaeD was studied in Escherichia coli whole ceils by using iso-pycnic sucrose density gradient centrifugation of isolated membranes, the detergents Triton X-100 and sodium lauryl sarcosinate and immunoblotting with a specific FaeD antiserum. Cells containing the complete K88 operon, as well as cells containing the sub-cloned faeD gene in various expression vectors, were used. Most of the FaeD was present in the outer membranes in a detergent-resistant form. Agglutination experiments with E coli cells expressing FaeD confirmed an outer membrane localization and indicated the presence of FaeD at the cell surface. Automated Edman degradation indicated that the mature FaeD contained 777 amino acid residues and confirmed that FaeD is synthesized with a rather long signal sequence of 35 amino acid residues. Twelve different FaeD–PhoA fusion proteins were prepared and characterized by nucleotide sequencing and immuno-blotting. Most of these fusion sites were located in the amino-terminal and carboxyl-terminal regions of FaeD. Six amino-terminal fusion proteins were soluble proteins in the peripiasm, whereas the other fusion proteins were associated with the outer membrane. The protease accessibility of FaeD and of the six outer membrane-bound FaeD–PhoA fusion proteins was studied using whole cells, cells with permeabilized outer membranes, and isolated membranes. Collagenase H, kallikrein, trypsin and proteinase K were used. Based on the results of these experiments and computer predictions, a model for the membrane topology of FaeD was developed in which FaeD contains a large central domain containing 24 membrane-spanning segments and two relatively large periplasmic regions, at the amino-terminal and carboxyl-terminal end of the protein, respectively. 相似文献
65.
Aaron M. Shew Lawton L. Nalley Diana M. Danforth Bruce L. Dixon Rodolfo M. Nayga Jr Anne‐Cecile Delwaide Barbara Valent 《Plant biotechnology journal》2016,14(1):4-7
India has more than 215 million food‐insecure people, many of whom are farmers. Genetically modified (GM) crops have the potential to alleviate this problem by increasing food supplies and strengthening farmer livelihoods. For this to occur, two factors are critical: (i) a change in the regulatory status of GM crops, and (ii) consumer acceptance of GM foods. There are generally two classifications of GM crops based on how they are bred: cisgenically bred, containing only DNA sequences from sexually compatible organisms; and transgenically bred, including DNA sequences from sexually incompatible organisms. Consumers may view cisgenic foods as more natural than those produced via transgenesis, thus influencing consumer acceptance. This premise was the catalyst for our study—would Indian consumers accept cisgenically bred rice and if so, how would they value cisgenics compared to conventionally bred rice, GM‐labelled rice and ‘no fungicide’ rice? In this willingness‐to‐pay study, respondents did not view cisgenic and GM rice differently. However, participants were willing‐to‐pay a premium for any aforementioned rice with a ‘no fungicide’ attribute, which cisgenics and GM could provide. Although not significantly different (P = 0.16), 76% and 73% of respondents stated a willingness‐to‐consume GM and cisgenic foods, respectively. 相似文献
66.
Barbara S. Valent Alan G. Darvill Michael McNeil Børre K. Robertsen Peter Albersheim 《Carbohydrate research》1980,79(2):165-192
This paper describes a new glycosyl-sequencing method. This method was made possible by the ability to fractionate complex mixtures of peralkylated oligosaccharides by reversed-phase, high-pressure liquid chromatography. The fractionation ability of the reversed-phase system allows the isolation and subsequent unambiguous identification by g.l.c.-m.s. of disaccharides, almost all trisaccharides, and, in some cases, tetrasaccharides generated by successive partial acid hydrolysis, reduction, and ethylation of a permethylated, complex carbohydrate. As these small oligosaccharides overlap within the unhydrolyzed, complex carbohydrate, the oligosaccharide sequences may be pieced together, and, with the glycosyl-linkage composition of the intact complex carbohydrate, can be used to determine the glycosyl sequence of the complex carbohydrate. The details of the sequencing method are illustrated by the elucidation of the glycosyl sequences of three complex carbohydrates. These examples demonstrate the wide variety of complex carbohydrates whose structures can be ascertained by the new sequencing technique. Two of the examples are the commercially available polysaccharides, lichenan and xanthan, whose structures have already been reported. The other example is a nonasaccharide derived from xyloglucan, a structural polymer of plant cell-walls. The glycosyl residues of the complex carbohydrates studied include hexosyl, deoxyhexosyl, pentosyl, glycosyluronic, and pyruvic acetal-substituted hexosyl residues. It will be demonstrated that the new glycosyl-sequencing technique is not compromise by the presence, in the carbohydrate to be analyzed, of glycosyl linkages possessing very different acid labilities. Two major advantages of this sequencing technique are that it is relatively rapid and that it requires only milligram quantities of carbohydrate. 相似文献
67.
William E. Cooper Jr Valentín Pérez‐Mellado 《Biological journal of the Linnean Society. Linnean Society of London》2012,107(2):254-268
Island tameness (reduced escape behaviour on islands where prey have experienced prolonged relaxation of predation pressure) is known in several taxa, although the relationships between recent predation pressure and escape on islands are poorly known. We investigated escape by numerous populations exposed to differing predation pressure of two sister species of Podarcis lizards in the Balearic Islands. Our main findings are that flight initiation distance was greater in Podarcis pityusensis than Podarcis lilfordi and increased as predation pressure increased in P. pityusensis. Island tameness led to extinction of P. lilfordi on Menorca and Mallorca following anthropogenic introduction of predators; this species is extant only on nearby islets. The lack of relationship between recent predation pressure and flight initiation distance in P. lilfordi indicates that the historically acquired deficit in the ability to adjust escape behaviour to predation pressure still exists. Podarcis pityusensis, which was exposed to greater natural predation pressure before human introduction of predators, survives on Ibiza and Formentera, as well as on islets. Retention of the ability to respond to predation pressure is consistent with our finding that flight initiation distance increases as predation pressure increases among current populations. © 2012 The Linnean Society of London, Biological Journal of the Linnean Society, 2012, ?? , ??–??. 相似文献
68.
Invasive infections caused by Candida spp. are increasing worldwide and are becoming an important cause of morbidity and mortality in immunocompromised patients. A large number of manifestations of candidiasis are associated with the formation of biofilms on inert or biological surfaces. Candida spp. biofilms are recalcitrant to treatment with conventional antifungal therapies. The aim of this study was dual 1) to determine the prevalence of biofilm producers among clinical isolates from catheter (16 C. albicans ) and blood culture (2 C. albicans and 30 C. tropicalis), and 2) to determine the activity of amphotericin B and anidulafungin against C. albicans and C. tropicalis biofilms of 24 and 48 hours of maturation. Biofilms were developed using a 96-well microtitre plate model and production and activity of antifungal agents against biofilms were determined by the tetrazolium (XTT) reduction assay. Of catheter and blood isolates, 62.5 and 56.25%, respectively, produced biofilms. By species, 68.42% of C. albicans and 53.33% of C. tropicalis were biofilm producers. C. albicans biofilms showed more resistance to amphotericin B and anidulafungin than their planktonic counterparts. Complete killing of biofilms was never achieved, even at the highest concentrations of the drugs tested. Anidulafungin displayed more activity than amphotericin B against C. albicans biofilms of 24 hours of maturation (GM MIC 0.354 vs. 0.686 microg/ml), but against C. tropicalis biofilms amphotericin B was more active (GM MIC 11.285 vs. 0.476 microg/ml). In contrast, against biofilms with 48 hours maturation, amphotericin B was more active against both species. 相似文献
69.
Gérald Larrouy-Maumus Henrieta ?kovierová Rabeb Dhouib Shiva Kumar Angala Sophie Zuberogoitia Ha Pham Anne Drumond Villela Katarina Miku?ová Audrey Noguera Martine Gilleron Lucia Valentínová Jana Korduláková Patrick. J. Brennan Germain Puzo Jér?me Nigou Mary Jackson 《The Journal of biological chemistry》2012,287(47):39933-39941
The biosynthesis of the major cell envelope glycoconjugates of Mycobacterium tuberculosis is topologically split across the plasma membrane, yet nothing is known of the transporters required for the translocation of lipid-linked sugar donors and oligosaccharide intermediates from the cytoplasmic to the periplasmic side of the membrane in mycobacteria. One of the mechanisms used by prokaryotes to translocate lipid-linked phosphate sugars across the plasma membrane relies on translocases that share resemblance with small multidrug resistance transporters. The presence of an small multidrug resistance-like gene, Rv3789, located immediately upstream from dprE1/dprE2 responsible for the formation of decaprenyl-monophosphoryl-β-d-arabinose (DPA) in the genome of M. tuberculosis led us to investigate its potential involvement in the formation of the major arabinosylated glycopolymers, lipoarabinomannan (LAM) and arabinogalactan (AG). Disruption of the ortholog of Rv3789 in Mycobacterium smegmatis resulted in a reduction of the arabinose content of both AG and LAM that accompanied the accumulation of DPA in the mutant cells. Interestingly, AG and LAM synthesis was restored in the mutant not only upon expression of Rv3789 but also upon that of the undecaprenyl phosphate aminoarabinose flippase arnE/F genes from Escherichia coli. A bacterial two-hybrid system further indicated that Rv3789 interacts in vivo with the galactosyltransferase that initiates the elongation of the galactan domain of AG. Biochemical and genetic evidence is thus consistent with Rv3789 belonging to an AG biosynthetic complex, where its role is to reorient DPA to the periplasm, allowing this arabinose donor to then be used in the buildup of the arabinan domains of AG and LAM. 相似文献
70.
Cagnacci F Bolzoni L Rosà R Carpi G Hauffe HC Valent M Tagliapietra V Kazimirova M Koci J Stanko M Lukan M Henttonen H Rizzoli A 《International journal for parasitology》2012,42(4):365-372
Tick borne encephalitis (TBE) is endemic to eastern and central Europe with broad temporal and spatial variation in infection risk. Although many studies have focused on understanding the environmental and socio-economic factors affecting exposure of humans to TBE, comparatively little research has been devoted to assessing the underlying ecological mechanisms of TBE occurrence in enzootic cycles, and therefore TBE hazard. The aim of this study was to evaluate the effect of the main ungulate tick hosts on the pattern of tick infestation in rodents and TBE occurrence in rodents and questing adult ticks. In this empirical study, we considered three areas where endemic human TBE occurs and three control sites having no reported human TBE cases. In these six sites located in Italy and Slovakia, we assessed deer density using the pellet group count-plot sampling technique, collected questing ticks, live-trapped rodents (primarily Apodemus flavicollis and Myodes glareolus) and counted ticks feeding on rodents. Both rodents and questing ticks were screened for TBE infection. TBE infection in ticks and rodents was positively associated with the number of co-feeding ticks on rodents and negatively correlated with deer density. We hypothesise that the negative relationship between deer density and TBE occurrence on a local scale (defined by the minimum overlapping area of host species) could be attributed to deer (incompetent hosts) diverting questing ticks from rodents (competent hosts), know as the 'dilution effect hypothesis'. We observed that, after an initial increase, the number of ticks feeding on rodents reached a peak for an intermediate value of estimated deer density and then decreased. Therefore, while at a regional scale, tick host availability has already been shown to be directly correlated with TBE distribution, our results suggest that the interactions between deer, rodents and ticks are much more complex on a local scale, supporting the possibility of a dilution effect for TBE. 相似文献