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121.
Cristina Tuni Reut Berger‐Tal 《Biological journal of the Linnean Society. Linnean Society of London》2012,107(4):910-919
The taxonomy of the Old World bat genus Otomops (Chiroptera: Molossidae) has been the subject of considerable debate. The failure of classical morphological studies to provide consistent patterns regarding interspecific relationships within Otomops has limited any understanding of the evolutionary history of the genus. We used traditional and geometric morphometric approaches to establish the species limits of taxa from sub‐Saharan Africa, the Arabian Peninsula, and Madagascar. Morphometric data supported the recent recognition of three distinct Afrotropical taxa: Otomops madagascariensis from Madagascar; Otomops martiensseni s.s. from southern, eastern, central, and western Africa; and an undescribed taxon from north‐east Africa and the Arabian Peninsula. Analyses of craniodental measurements and landmark‐based data showed significant cranial size and shape divergence between the three taxa. Cranial size and shape variation within Afro‐Arabian Otomops were strongly influenced by altitude, seasonality of precipitation, and precipitation in the driest month. Based on morphometric patterns and molecular divergence estimates, we suggest that morphological evolution within Afro‐Arabian Otomops occurred in response to the fluctuating climate during the Pleistocene on the one hand, and the increasing aridity and seasonality over north‐eastern Africa on the other. © 2012 The Linnean Society of London, Biological Journal of the Linnean Society, 2012, •• , ••–••. 相似文献
122.
Yasmin Silva Rizk Alice Fischer Marillin de Castro Cunha Patrik Oening Rodrigues Maria Carolina Silva Marques Maria de Fátima Cepa Matos M?nica Cristina Toffoli Kadri Carlos Alexandre Carollo Carla Cardozo Pinto de Arruda 《Memórias do Instituto Oswaldo Cruz》2014,109(8):1050-1056
This study is the first phytochemical investigation of Selaginella sellowii
and demonstrates the antileishmanial activity of the hydroethanolic extract
from this plant (SSHE), as well as of the biflavonoids amentoflavone and
robustaflavone, isolated from this species. The effects of these substances were
evaluated on intracellular amastigotes of Leishmania (Leishmania)
amazonensis, an aetiological agent of American cutaneous leishmaniasis.
SSHE was highly active against intracellular amastigotes [the half maximum inhibitory
concentration (IC50) = 20.2 µg/mL]. Fractionation of the extract led to the isolation
of the two bioflavonoids with the highest activity: amentoflavone, which was about
200 times more active (IC50 = 0.1 μg/mL) and less cytotoxic than SSHE (IC50 = 2.2 and
3 μg/mL, respectively on NIH/3T3 and J774.A1 cells), with a high selectivity index
(SI) (22 and 30), robustaflavone, which was also active against L.
amazonensis (IC50 = 2.8 µg/mL), but more cytotoxic, with IC50 = 25.5
µg/mL (SI = 9.1) on NIH/3T3 cells and IC50 = 3.1 µg/mL (SI = 1.1) on J774.A1 cells.
The production of nitric oxide (NO) was lower in cells treated with amentoflavone
(suggesting that NO does not contribute to the leishmanicidal mechanism in this
case), while NO release was higher after treatment with robustaflavone. S.
sellowii may be a potential source of biflavonoids that could provide
promising compounds for the treatment of cutaneous leishmaniasis. 相似文献
123.
Methyl CpG-binding proteins induce large-scale chromatin reorganization during terminal differentiation 下载免费PDF全文
Brero A Easwaran HP Nowak D Grunewald I Cremer T Leonhardt H Cardoso MC 《The Journal of cell biology》2005,169(5):733-743
Pericentric heterochromatin plays an important role in epigenetic gene regulation. We show that pericentric heterochromatin aggregates during myogenic differentiation. This clustering leads to the formation of large chromocenters and correlates with increased levels of the methyl CpG-binding protein MeCP2 and pericentric DNA methylation. Ectopic expression of fluorescently tagged MeCP2 mimicked this effect, causing a dose-dependent clustering of chromocenters in the absence of differentiation. MeCP2-induced rearrangement of heterochromatin occurred throughout interphase, did not depend on the H3K9 histone methylation pathway, and required the methyl CpG-binding domain (MBD) only. Similar to MeCP2, another methyl CpG-binding protein, MBD2, also increased during myogenic differentiation and could induce clustering of pericentric regions, arguing for functional redundancy. This MeCP2- and MBD2-mediated chromatin reorganization may thus represent a molecular link between nuclear genome topology and the epigenetic maintenance of cellular differentiation. 相似文献
124.
Alejandra Lazzaro Montserrat Corominas Cristina Martí Cristina Flors Laura R Izquierdo Teresa A Grillo Javier G Luis Santi Nonell 《Photochemical & photobiological sciences》2004,3(7):706-710
The light-induced singlet oxygen production and antifungal activity of phenylphenalenone phytoalexins isolated from infected banana plants (Musa acuminata) are reported. Upon absorption of light energy all studied phenylphenalenones sensitise the production of singlet oxygen in polar and non-polar media. Antifungal activity of these compounds towards Fusarium oxysporum is enhanced in the presence of light. These results, together with the correlation of IC50 values under illumination with the quantum yield of singlet oxygen production and the enhancing effect of D2O on the antifungal activity, suggest the intermediacy of singlet oxygen produced by electronic excitation of the phenylphenalenone phytoalexins. 相似文献
125.
Pura Díaz-Veiga Mayte Sancho Álvaro García Esther Rivas Elixabet Abad Nerea Suárez Gabriela Mondragón Cristina Buiza Ana Orbegozo Javier Yanguas 《Revista espa?ola de geriatría y gerontología》2014
Introduction
The Model of Person Centered Care has attracted increasing interest for use in gerontology centers. Therefore, the contributions about its impact are scarce in our context. The objective of this paper is to establish the impact that the interventions associated with the Model of Person Centered Care in the «Etxean Ondo» Project have on the quality of life of residents with cognitive impairment.Material and methods
One hundred and ninetten residents with cognitive impairment were selected: 59 in the control group and 60 in the experimental group. Subjects in each group were sorted by cognitive impairment: mild or severe. Changes were implemented in the physical and organizational environments for the promotion of autonomy and wellbeing. Quality of life was assessed before and 6 months after intervention using the Fumat Scales (mild cognitive impairment) and Qualid (severe cognitive impairment). The t-Student test was used for comparison of means.Results
In intergroup comparisons, significant differences in the Fumat Scale for the control group with mild cognitive impairment were initially identified. These differences were not recorded in the post assessment. The experimental group with severe cognitive impairment was significantly improved in the Qualid Scale post assessment. In intragroup comparisons, significant improvements were evident in the quality of life of experimental subjects, both with severe cognitive impairment (Qualid) and mild (Fumat).Conclusions
The findings support the effectiveness of the interventions and identify methodological and conceptual issues that have been considered to analyze the Model of Person Centered Care efects. 相似文献126.
Cartesio Favalli Teresa Jezzi Antonio Mastino Cristina Rinaldi-Garaci Carlo Riccardi Enrico Garaci 《Cancer immunology, immunotherapy : CII》1985,20(3):189-192
Summary A single injection of -interferon (-IFN) (30 000 units/mouse), a major biological modifier of natural killer (NK) cytolytic activity, strongly stimulated NK activity in normal mice, as expected, while the same treatment did not statistically alter the NK response in cyclophosphamide (CY)-suppressed animals.We investigated the possibility of thymosin 1 cooperating with -IFN in boosting NK activity in CY-suppressed animals.The results show that treatment with thymosin 1 (200 g/kg) for 4 days, followed by a single injection of -IFN 24 h before testing, strongly restored NK activity in CY-suppressed mice. Thymosin 1 was, moreover, able to accelerate the recovery rate of NK activity in bone marrow reconstituted murine chimeras.Taken together the data support the concept that the synergic effect between thymosin 1 and -IFN could be the result of effects on differentiation of the NK lineage at different levels. 相似文献
127.
A comparative analysis of microscopic alterations in modern and ancient undecalcified and decalcified dry bones 下载免费PDF全文
128.
Production of moss‐dominated biocrusts to enhance the stability and function of the margins of artificial water bodies 下载免费PDF全文
Ricardo Cruz de Carvalho Patrícia dos Santos Cristina Branquinho 《Restoration Ecology》2018,26(3):419-421
Margins of water reservoirs associated with dams can have high‐frequency tides, promoting soil erosion and nutrient leaching. We propose the use of biocrusts for restoration and ecological engineering purposes, due to their poikilohydric character, to stabilize reservoir margins. We promoted biocrust growth under controlled conditions, testing two types of substrate: native sand and organic substrate. After 2 months, biocrusts grew on organic substrate covering almost all the area, but not on native sand. This fast and easy nature‐based solution for soil stabilization can be used as an environmental engineering tool in highly degraded sites. 相似文献
129.
130.
Colombo F Tintori C Furlan A Borrelli S Christodoulou MS Dono R Maina F Botta M Amat M Bosch J Passarella D 《Bioorganic & medicinal chemistry letters》2012,22(14):4693-4696
The use of Cu(I)-catalyzed azide-alkyne 1,3-dipolar cycloaddition permitted the synthesis of a new compound that is able to inhibit the HGF-induced scattering of MDCK (epithelial cells) and in vitro tumorigenesis of H1437 (non-small-cell lung cancer) and GTL-16 (human gastric carcinoma). In agreement with biochemical and biological results, docking studies within the ATP binding site of Met suggested for the new synthesized compound a binding mode similar to that of the active compound Triflorcas previously reported. 相似文献