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1.
Elio R.D. Castillo Dardo A. Martí Maximiliano M. Maronna María C. Scattolini Diogo C. Cabral‐de‐Mello María M. Cigliano 《Systematic Entomology》2019,44(1):61-74
In an attempt to unveil the origin of neo‐sex chromosomes in Ronderosia Cigliano grasshoppers, we performed a combined phylogenetic analysis based on morphological (external morphology and male genitalia) and molecular data (COI, COII, 16S and ITS2) to explore the chromosome evolution within the genus. We also analysed the distributional patterns of the various Ronderosia species and considered the possible role of chromosome rearrangements (CRs) in speciation processes within the genus in the light of ‘suppressed‐recombination’ models. We mapped the states of three chromosomal characters on the combined tree topology. The combined evidence supported Ronderosia as a monophyletic group. The cytogenetic analyses of the genus demonstrated the importance of rearranged karyotypes with single, complex and multiples neo‐sex chromosome determination systems in all species. The chromosome character optimisation suggests X‐autosome centric fusion as the mechanism responsible for neo‐sex chromosome formation in most Ronderosia species, except in R. dubia and R. bergii. Similar autosomes were involved in fusions with the ancestral X chromosome in Ronderosia, supporting previous hypotheses on the unique origin of X‐autosome fusion for the sex chromosome in the genus. As a source of chromosome variation, autosome‐autosome centric fusion played a secondary role in Ronderosia compared with other Dichroplini. Given the homogeneity in the morphological features, the sympatric distribution of closely related species and the intrinsic property of centric fusion as suppressors of the crossing over, we suggest that CRs may have played a key role during the speciation process within Ronderosia. 相似文献
2.
It has long been assumed that serial homologues are ancestrally similar—polysomerism resulting from a “duplication” or “repetition” of forms—and then often diverge—anisomerism, for example, as they become adapted to perform different tasks as is the case with the forelimb and hind limbs of humans. However, such an assumption, with crucial implications for comparative, evolutionary, and developmental biology, and for evolutionary developmental biology, has in general not really been tested by a broad analysis of the available empirical data. Perhaps not surprisingly, more recent anatomical comparisons, as well as molecular knowledge of how, for example, serial appendicular structures are patterned along with different anteroposterior regions of the body axis of bilateral animals, and how “homologous” patterning domains do not necessarily mark “homologous” morphological domains, are putting in question this paradigm. In fact, apart from showing that many so-called “serial homologues” might not be similar at all, recent works have shown that in at least some cases some “serial” structures are indeed more similar to each other in derived taxa than in phylogenetically more ancestral ones, as pointed out by authors such as Owen. In this article, we are taking a step back to question whether such assumptions are actually correct at all, in the first place. In particular, we review other cases of so-called “serial homologues” such as insect wings, arthropod walking appendages, Dipteran thoracic bristles, and the vertebrae, ribs, teeth, myomeres, feathers, and hairs of chordate animals. We show that: (a) there are almost never cases of true ancestral similarity; (b) in evolution, such structures—for example, vertebra—and/or their subparts—for example, “transverse processes”—many times display trends toward less similarity while in many others display trends toward more similarity, that is, one cannot say that there is a clear, overall trend to anisomerism. 相似文献
3.
Maria Ieda Siqueira Linhares Yoshito Eizuru Gildete Patriota de Andrade Ivailda Barbosa Fonseca Luiz Bezerra Carvalho Ivanildo Tenorio Moreira Yoichi Minamishima 《Microbiology and immunology》1994,38(6):475-478
The seroprevalence of human T cell leukemia virus type 1 (HTLV-1) infection was investigated in Brazilians (570): native inhabitants (298) and descendants from Japanese (272) living in Recife and its neighborhoods—North-east of Brazil. Furthermore, polytransfused renal transplanted patients (54) were also examined for the serological status to this virus. The seropositivity to HTLV-1, screened by enzyme-linked immunosorbent assay (ELISA), was low: 1.34% for the local population and 0.73% for the descendants from Japanese. However, the seropositivity for the renal transplanted patients was found to be 11.1%. This higher value suggests that this retrovirus infection seems to be of importance in this clinical condition. 相似文献
4.
Neuza Domingues André R. A. Marques Rita Diogo Almeida Calado Inês S. Ferreira Cristiano Ramos José Ramalho Maria I. L. Soares Telmo Pereira Luís Oliveira José R. Vicente Louise H. Wong Inês C. M. Simões Teresa M. V. D. Pinho e Melo Andrew Peden Cláudia Guimas Almeida Clare E. Futter Rosa Puertollano Winchil L. C. Vaz Otília V. Vieira 《Traffic (Copenhagen, Denmark)》2023,24(7):284-307
5.
Janaine Almeida Neto Daniel Amando Nery Katia Simoni Bezerra Lima Maria Eduarda Gomes da Cruz Silva Tarcísio Cícero de Lima Araújo Nathália Andrezza Carvalho de Souza Rodolfo Hideki Vicente Nishimura Camila de Souza Araújo Ana Paula de Oliveira Jackson Roberto Guedes da Silva Almeida Larissa Araújo Rolim 《化学与生物多样性》2023,20(3):e202201039
This article describes the phytochemical study of Cannabis sativa roots from northeastern Brazil. The dried plant material was pulverized and subjected to exhaustive maceration with ethanol at room temperature, obtaining the crude ethanolic extract (Cs-EEBR). The volatile compounds were analyzed by gas chromatography coupled with mass spectrometry (GC/MS), which allowed to identify 22 compounds by comparing the linear retention index (LRI), the similarity index (SI) and the fragmentation pattern of the constituents with the literature. By this technique the major compounds identified were: friedelan-3-one and β-sitosterol. In addition, two fractions were obtained from Cs-EEBR by classical column chromatography and preparative thin layer chromatography. These fractions were analyzed by NMR and IR and together with the mass spectrometry data allowed to identify the compounds: epifriedelanol, friedelan-3-one, β-sitosterol and stigmasterol. The study contributed to the phytochemical knowledge of Cannabis sativa, specifically the roots, as there are few reports on the chemical constituents of this part of the plant. 相似文献
6.
Pedro F. P. Brandão-Dias Daniel M. C. Hallack Elise D. Snyder Jennifer L. Tank Diogo Bolster Sabrina Volponi Arial J. Shogren Gary A. Lamberti Kyle Bibby Scott P. Egan 《Molecular ecology resources》2023,23(4):756-770
Environmental DNA (eDNA) analysis is a powerful tool for remote detection of target organisms. However, obtaining quantitative and longitudinal information from eDNA data is challenging, requiring a deep understanding of eDNA ecology. Notably, if the various size components of eDNA decay at different rates, and we can separate them within a sample, their changing proportions could be used to obtain longitudinal dynamics information on targets. To test this possibility, we conducted an aquatic mesocosm experiment in which we separated fish-derived eDNA components using sequential filtration to evaluate the decay rate and changing proportion of various eDNA particle sizes over time. We then fit four alternative mathematical decay models to the data, building towards a predictive framework to interpret eDNA data from various particle sizes. We found that medium-sized particles (1–10 μm) decayed more slowly than other size classes (i.e., <1 and > 10 μm), and thus made up an increasing proportion of eDNA particles over time. We also observed distinct eDNA particle size distribution (PSD) between our Common carp and Rainbow trout samples, suggesting that target-specific assays are required to determine starting eDNA PSDs. Additionally, we found evidence that different sizes of eDNA particles do not decay independently, with particle size conversion replenishing smaller particles over time. Nonetheless, a parsimonious mathematical model where particle sizes decay independently best explained the data. Given these results, we suggest a framework to discern target distance and abundance with eDNA data by applying sequential filtration, which theoretically has both metabarcoding and single-target applications. 相似文献
7.
8.
Carlos F. de Mello Diego D. De La Vega Leandro T. Pizutti Fabiane P. Lopes Maribel A. Rubin Jaime G. Homerich Dr. Carlos R. Melo Joana E. Somer Diogo O. Souza Moacir Wajner 《Neurochemical research》1995,20(12):1437-1441
The effect ofl-pyroglutamic acid, a metabolite that accumulates in pyroglutamic aciduria, on different neurochemical parameters was investigated in adult male Wistar rats. Glutamate binding, adenylate cyclase activity and G protein coupling to adenylate cyclase were assayed in the presence of the acid.l-pyroglutamic acid decreased Na+-dependent and Na+-independent glutamate binding Basal and GMP-PNP stimulated adenylate cyclase activity were not affected by the acid. Furthermore, rats received unilateral intrastriatal injections of 10–300 nmol of bufferedl-pyroglutamic acid. Vehicle (0.25 M Tris-Cl, pH 7.35–7.4) was injected into the contralateral striatum. Neurotoxic damage was assessed seven days after the injection by histological examination and by weighing both cerebral hemispheres. No difference in histology or weight could be identified between hemispheres. These results suggest that, although capable of interfering with glutamate binding, pyroglutamate did not cause a major lesion in the present model of neurotoxicity. 相似文献
9.
Summary Four siblings with the autosomal recessive Roberts syndrome are reported, and we discuss the phenotypic overlap of this syndrome with other similar radial, aplasia syndromes. 相似文献
10.
Ascorbate oxidase is present in homogenates of the flesh of Cucurbita maxima fruits. Its activity is independent of ascorbate concentration over th 相似文献