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341.
Bienvenu T Villard L De Roux N Bourdon V Fontes M Beldjord C Tardieu M Jonveaux P Chelly J;French Consortium for MECP Gene Analysis 《Genetic testing》2002,6(1):1-6
Mutations in the MECP2 (Methyl-CpG-binding protein) gene recently have been reported to cause Rett syndrome (RTT), an X-linked progressive encephalopathy. We have collected the results of MECP2 analysis conducted in four laboratories in France. A total of 301 RTT alleles have been analyzed, demonstrating a total of 69 different mutations so far observed and accounting for 64% of MECP2 genes in RTT patients living in France. R168X (11.5%) is the most common of MECP2 mutations, followed by R255X (10.9%), R270X (10.5%), T158M (7.8%), and R306C (6.8%). Only 10 mutations had a relative frequency > 2%. A total of 59 mutations were found in a small number of RTT alleles (from 1 to 2). These data demonstrate the high allelic heterogeneity of RTT in France and provide information relevant to the development of strategies for molecular diagnosis and genetic counseling in RTT families. 相似文献
342.
Paulo E. Cabral Filho Mariana P. Cabrera Ana L.C. Cardoso Otacilio A. Santana Carlos F.G.C. Geraldes Beate S. Santos Maria C. Pedroso de Lima Giovannia A.L. Pereira Adriana Fontes 《Biochimica et Biophysica Acta (BBA)/General Subjects》2018,1862(12):2788-2796
Background
Site-specific multimodal nanoplatforms with fluorescent-magnetic properties have great potential for biological sciences. For this reason, we developed a multimodal nanoprobe (BNPs-Tf), by covalently conjugating an optical-magnetically active bimodal nanosystem, based on quantum dots and iron oxide nanoparticles, with the human holo-transferrin (Tf).Methods
The Tf bioconjugation efficiency was evaluated by the fluorescence microplate assay (FMA) and the amount of Tf immobilized on BNPs was quantified by fluorescence spectroscopy. Moreover, relaxometric and fluorescent properties of the BNPs-Tf were evaluated, as well as its ability to label specifically HeLa cells. Cytotoxicity was also performed by Alamar Blue assay.Results
The FMA confirmed an efficient bioconjugation and the fluorescence spectroscopy analysis indicated that 98% of Tf was immobilized on BNPs. BNPs-Tf also presented a bright fluorescence and a transversal/longitudinal relaxivities ratio (r2/r1) of 65. Importantly, the developed BNPs-Tf were able to label, efficiently and specifically, the Tf receptors in HeLa cells, as shown by fluorescence and magnetic resonance imaging assays. Moreover, this multimodal system did not cause noteworthy cytotoxicity.Conclusions
The prepared BNPs-Tf hold great promise as an effective and specific multimodal, highly fluorescent-magnetic, nanoplatform for fluorescence analyses and T2-weighted images.General significance
This study developed an attractive and versatile multimodal nanoplatform that has potential to be applied in a variety of in vitro and in vivo studies, addressing biological processes, diagnostic, and therapeutics. Moreover, this work opens new possibilities for designing other efficient multimodal nanosystems, considering other biomolecules in their composition able to provide them important functional properties. 相似文献343.
C.R.A. Cunha A.D.P.R. Oliveira T.V.C. Firmino D.P.L.A. Tenório G. Pereira L.B. Carvalho B.S. Santos M.T.S. Correia A. Fontes 《Biochimica et Biophysica Acta (BBA)/General Subjects》2018,1862(3):427-439
Background
Quantum dots (QDs) are outstanding nanomaterials of great interest to life sciences. Their conjugation versatility added to unique optical properties, highlight these nanocrystals as very promising fluorescent probes. Among uncountable new nanosystems, in the last years, QDs conjugated to glycans or lectins have aroused a growing attention and their application as a tool to study biological and functional properties has increased.Scope of review
This review describes the strategies, reported in the literature, to conjugate QDs to lectins or carbohydrates, providing valuable information for the elaboration, improvement, and application of these nanoconjugates. It also presents the main applications of these nanosystems in glycobiology, such as their potential to study microorganisms, the development of diseases such as cancer, as well as to develop biosensors.Major conclusions
The development of glyconanoparticles based on QDs emerged in the last decade. Many works reporting the conjugation of QDs with carbohydrates and lectins have been published, using different strategies and reagents. These bioconjugates enabled studies that are very sensitive and specific, with potential to detect and elucidate the glycocode expressed in various normal or pathologic conditions.General significance
Produce a quick reference source over the main advances reached in the glyconanotechnology using QDs as fluorescent probes. 相似文献344.
There is an alpha-actin skeletal muscle-specific gene in a salamander (Pleurodeles waltlii) 总被引:1,自引:0,他引:1
We cloned, from a cDNA library, an alpha-actin sequence from a salamander (Pleurodeles waltlii), which codes for the 125 COOH-terminal amino acid residues of a skeletal muscle actin (without any difference from the corresponding protein of warm blood vertebrates). An important conservation in the 3' untranslated region between this sequence and skeletal alpha-actin genes of chicken and man was noted. These results demonstrate, contrary to what was thought previously, that there exists in salamander a true skeletal alpha-actin gene. The results suggest that striated muscle actin genes in lower vertebrates could be a mosaic of cardiac and skeletal-specific amino acid residues, and that the divergence between these two types of genes is older than the NH2-terminal analysis of actins suggested previously. 相似文献
345.
Analysis of the biomass quality and photosynthetic efficiency of a nitrogen-fixing cyanobacterium grown outdoors with two agitation systems 总被引:1,自引:0,他引:1
The efficiency of two different agitation systems (airlift and paddlewheel) in the biomass photoproduction of a nitrogen-fixing filamentous blue-green alga was evaluated outdoors, and the elemental and molecular composition of the cells grown with each system was analyzed. With the paddlewheel system, the productivity values achieved were over 30% higher than with the airlift system, both in summer and winter. In this last season, a conversion efficiency of total solar energy into stored biomass energy of 3.3% was estimated for the paddlewheel system. Moreover, the algal cells grown with this system exhibited a higher net protein (58.9% of dry weight) and nitrogen (11.3%) content than those grown with the airlift device, with an estimated nitrogen fixation rate of more than 2 g N m(-2) day(-1). These advantages of the paddlewheel system make this procedure more appropriate for the large-scale photoproduction of nitrogen-fixing blue-green algae outdoors. 相似文献
346.
Juan Luis Gómez-Pinchetti Ziyadin Ramazanov Agustín Fontes Guillermo García-Reina 《Journal of applied phycology》1992,4(1):11-15
Photosynthetic characteristics of Dunaliella salina with high (red form) and low β-carotene (green form) concentrations were studied. D. salina growing in brine saltworks exhibited a high level of β-carotene (15 pg cell−1). The rate of oxygen evolution as a function of irradiance was higher in the red than in the green form (on chlorophyll basis).
Photosynthetic inhibition of the green form was observed above 500 μmol m−2 s−1. The red form appeared more resistant to high irradiance and no inhibition in O2 evolution was observed up 2000 μmol m−2 s−1. However, when these results are expressed on a cell number basis the rate of oxygen evolution was significantly higher in
the green form.
Carbonic anhydrase (CA) activity (total, soluble, membrane bound) was found in red and green forms. CA was higher in the red
form on a chlorophyll basis, but lower if expressed on a protein basis. The light dependent rate of oxygen evolution and photoinhibition
depends on the concentration of β-carotene in D. salina cells. 相似文献
347.
348.
Involvement of Src signaling in the synergistic effect between cisplatin and digoxin on cancer cell viability 下载免费PDF全文
349.
350.
Replication Protein A‐1 Has a Preference for the Telomeric G‐rich Sequence in Trypanosoma cruzi 下载免费PDF全文
Raphael Souza Pavani Marcela O. Vitarelli Carlos A. H. Fernandes Fabio F. Mattioli Mariana Morone Milene C. Menezes Marcos R. M. Fontes Maria Isabel N. Cano Maria Carolina Elias 《The Journal of eukaryotic microbiology》2018,65(3):345-356
Replication protein A (RPA), the major eukaryotic single‐stranded binding protein, is a heterotrimeric complex formed by RPA‐1, RPA‐2, and RPA‐3. RPA is a fundamental player in replication, repair, recombination, and checkpoint signaling. In addition, increasing evidences have been adding functions to RPA in telomere maintenance, such as interaction with telomerase to facilitate its activity and also involvement in telomere capping in some conditions. Trypanosoma cruzi, the etiological agent of Chagas disease is a protozoa parasite that appears early in the evolution of eukaryotes. Recently, we have showed that T. cruziRPA presents canonical functions being involved with DNA replication and DNA damage response. Here, we found by FISH/IF assays that T. cruziRPA localizes at telomeres even outside replication (S) phase. In vitro analysis showed that one telomeric repeat is sufficient to bind RPA‐1. Telomeric DNA induces different secondary structural modifications on RPA‐1 in comparison with other types of DNA. In addition, RPA‐1 presents a higher affinity for telomeric sequence compared to randomic sequence, suggesting that RPA may play specific roles in T. cruzi telomeric region. 相似文献