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1.
J Alzheimers Dis Rep ; 7(1): 613-625, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37483326

RESUMEN

Background: Alzheimer's disease (AD) has several risk factors. APOE4 is the main one, and it has been suggested that there may be a synergy between it and BCHE-K as a risk factor. Objective: To investigate the association between APOE4 and BCHE-K as a risk factor for AD. Methods: We searched PubMed, Web of Science, Embase, and Scopus on August 8, 2021 for studies that analyzed the association of APOE4 and BCHE-K with AD. The random effect model was performed in meta-analysis according to age group. A chi-square was performed with the meta-analysis data to verify if the effect found is not associated only with the E4 allele. Results: Twenty-one studies with 6,853 subjects (3,528 AD and 3,325 Controls) were included in the meta-analysis. The quality of the evidence is moderate. There is a positive E4-K association for subjects with AD as shown by the odds ratio of 3.43. The chi-square meta test, which measures the probability that the E4-K association is due to chance, has an odds ratio of 6.155, indicating that the E4-K association is not a random event. The odds ratio of an E4-K association in subjects with AD increases to OR 4.46 for the 65- to 75-year-old group and OR 4.15 for subjects older than 75 years. The probability that the E4-K association is due to chance is ruled out by chi-square meta test values of OR 8.638 and OR 9.558. Conclusion: The synergy between APOE4 and BCHE-K is a risk factor for late-onset AD.

2.
Neotrop Entomol ; 50(4): 515-523, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33846963

RESUMEN

The insect/plant interaction is known to be a trigger for diversification and even speciation. Experimental analyses on fitness traits and phenotypic variation using alternative host sites have been performed to understand the process of diversification relative to insect/plant interactions. For cactophilic species of Drosophila, the speciation process is considered an adaptive radiation in response to the exploration of species of the Cactaceae as breeding and feeding sites. In this work, we analyzed life history and morphological traits in individuals from two phyletic lineages (Evolutionarily Significant Units ESU) of the cactophilic species Drosophila meridionalis (Wasserman 1962) (Diptera: Drosophilidae) raised from media prepare. The characters analyzed corresponded to viability, developmental time, and four morphological measurements. The experiments were performed in a semi-natural medium prepared with fermenting tissues of the natural hosts, Cereus hildmaniannus and Opuntia monacantha. Viability, development time, and three morphological measurements were influenced by lineage, suggesting differentiation between the lineages. However, in O. monacantha, the mean viability was greater (~15%) and development time was longer (~336 h) than in C. hildmaniannus (~11% and ~301 h, respectively). Only the developmental time was significantly affected by the host cactus. In general, ESU group A had better values than ESU group BC for the evaluated traits. This finding suggested differentiation between the two lineages and different plastic responsiveness to the contrasting environments of the hosts, and that C. hildmaniannus may be a relatively stressful environment for the larvae, as for other Drosophila species.


Asunto(s)
Cactaceae , Drosophila , Filogenia , Animales , Drosophila/clasificación , Fenotipo
3.
Rev. bras. entomol ; 59(4): 337-342, Oct.-Dec. 2015. tab, graf
Artículo en Inglés | LILACS | ID: lil-769919

RESUMEN

ABSTRACT The population dynamics of a species tends to change from the core to the periphery of its distribution. Therefore, one could expect peripheral populations to be subject to a higher level of stress than more central populations (the center–periphery hypothesis) and consequently should present a higher level of fluctuating asymmetry. To test these predictions we study asymmetry in wing shape of five populations of Drosophila antonietae collected throughout the distribution of the species using fluctuating asymmetry as a proxy for developmental instability. More specifically, we addressed the following questions: (1) what types of asymmetry occur in populations of D. antonietae? (2) Does the level of fluctuating asymmetry vary among populations? (3) Does peripheral populations have a higher fluctuating asymmetry level than central populations? We used 12 anatomical landmarks to quantify patterns of asymmetry in wing shape in five populations of D. antonietae within the framework of geometric morphometrics. Net asymmetry – a composite measure of directional asymmetry + fluctuating asymmetry – varied significantly among populations. However, once net asymmetry of each population is decomposed into directional asymmetry and fluctuating asymmetry, most of the variation in asymmetry was explained by directional asymmetry alone, suggesting that populations of D. antonietae have the same magnitude of fluctuating asymmetry throughout the geographical distribution of the species. We hypothesize that larval development in rotting cladodes might play an important role in explaining our results. In addition, our study underscores the importance of understanding the interplay between the biology of a species and its geographical patterns of asymmetry.

4.
Zoolog Sci ; 32(2): 141-50, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25826062

RESUMEN

Drosoph1la ornatifrons of the guarani group (Diptera: Drosophilidae) is found mainly in humid areas of the Atlantic Forest biome, especially in the southern region of Brazil. Historical and contemporary fragmentation events influenced species diversity and distribution in this biome, although the role of paleoclimatic and paleogeographic events remain to be verified. The objective of the present study was to evaluate the demographic structure of D. ornatifrons from collection sites that are remnants of Atlantic Forest in southern Brazil, in order to contribute to the understanding of the processes that affected the patterns of genetic variability in this species. To achieve this goal, we sequenced 51 individuals from nine localities and 64 individuals from six localities for the mitochondrial genes Cytochrome Oxidase I and II, respectively. Our results indicate that D. ornatifrons may have experienced a demographic expansion event from the southernmost locations of its distribution, most likely from those located next to the coast and in fragments of Atlantic Forest inserted in the Pampa biome (South 2 group), towards the interior (South 1 group). This expansion probably started after the last glacial maximum, between 20,000 and 18,000 years ago, and was intensified near the Pleistocene-Holocene transition, around 12,000 years ago, when temperature started to rise. In this work we discuss how the haplotypes found barriers to gene flow and dispersal, influenced by the biogeographic pattern of Atlantic Forest.


Asunto(s)
Evolución Biológica , Drosophila/clasificación , Drosophila/genética , Bosques , 7-Alcoxicumarina O-Dealquilasa , Animales , Brasil , Complejo IV de Transporte de Electrones/genética , Complejo IV de Transporte de Electrones/metabolismo , Regulación Enzimológica de la Expresión Génica/fisiología , Variación Genética , Haplotipos , Filogeografía
5.
Protein Pept Lett ; 13(1): 83-9, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16454675

RESUMEN

The present work reports the characterization of Fastuosain, a novel cysteine protease of 25kDa, purified from the unripe fruits of Bromelia fastuosa, a wild South American Bromeliaceae. Proteolytic activity, measured using casein and synthetic substrates, was dependent on the presence of thiol reagents, having maximum activity at pH 7.0. The present work reports cDNA cloning of Fastuosain; cDNA was amplified by PCR using specific primers. The product was 1096pb long. Mature fastuosain has 217 residues, and with the proregion has a total length of 324 residues. Its primary sequence showed high homology with ananain(74%), stem bromelain (66%) and papain (44%).


Asunto(s)
Bromelia/enzimología , Cisteína Endopeptidasas/farmacología , Secuencia de Aminoácidos , Secuencia de Bases , Cromatografía por Intercambio Iónico , Clonación Molecular , Cisteína Endopeptidasas/química , Cisteína Endopeptidasas/genética , Cisteína Endopeptidasas/aislamiento & purificación , Cartilla de ADN , ADN Complementario , Electroforesis en Gel de Poliacrilamida , Datos de Secuencia Molecular , Homología de Secuencia de Aminoácido
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