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51.
Marta Clariano Vanda Marques João Vaz Salma Awam Marta B. Afonso Maria Jesus Perry Cecília MP Rodrigues 《化学与生物多样性》2023,20(3):e202300222
Curcumin has a plethora of biological properties, making this compound potentially effective in the treatment of several diseases, including cancer. However, curcumin clinical use is compromised by its poor pharmacokinetics, being crucial to find novel analogs with better pharmacokinetic and pharmacological properties. Here, we aimed to evaluate the stability, bioavailability and pharmacokinetic profiles of monocarbonyl analogs of curcumin. A small library of monocarbonyl analogs of curcumin 1a–q was synthesized. Lipophilicity and stability in physiological conditions were both assessed by HPLC-UV, while two different methods assessed the electrophilic character of each compound monitored by NMR and by UV-spectroscopy. The potential therapeutic effect of the analogs 1a–q was evaluated in human colon carcinoma cells and toxicity in immortalized hepatocytes. Our results showed that the curcumin analog 1e is a promising agent against colorectal cancer, with improved stability and efficacy/safety profile. 相似文献
52.
Roberto de la Herrán Miguel Hermida Juan Andres Rubiolo Jèssica Gómez-Garrido Fernando Cruz Francisca Robles Rafael Navajas-Pérez Andres Blanco Paula Rodriguez Villamayor Dorinda Torres Pablo Sánchez-Quinteiro Daniel Ramirez Maria Esther Rodríguez Alberto Arias-Pérez Ismael Cross Neil Duncan Teresa Martínez-Peña Ana Riaza Adrian Millán M. Cristina De Rosa Davide Pirolli Marta Gut Carmen Bouza Diego Robledo Laureana Rebordinos Tyler Alioto Carmelo Ruíz-Rejón Paulino Martínez 《Molecular ecology resources》2023,23(4):886-904
Sex determination (SD) shows huge variation among fish and a high evolutionary rate, as illustrated by the Pleuronectiformes (flatfishes). This order is characterized by its adaptation to demersal life, compact genomes and diversity of SD mechanisms. Here, we assembled the Solea senegalensis genome, a flatfish of great commercial value, into 82 contigs (614 Mb) combining long- and short-read sequencing, which were next scaffolded using a highly dense genetic map (28,838 markers, 21 linkage groups), representing 98.9% of the assembly. Further, we established the correspondence between the assembly and the 21 chromosomes by using BAC-FISH. Whole genome resequencing of six males and six females enabled the identification of 41 single nucleotide polymorphism variants in the follicle stimulating hormone receptor (fshr) consistent with an XX/XY SD system. The observed sex association was validated in a broader independent sample, providing a novel molecular sexing tool. The fshr gene displayed differential expression between male and female gonads from 86 days post-fertilization, when the gonad is still an undifferentiated primordium, concomitant with the activation of amh and cyp19a1a, testis and ovary marker genes, respectively, in males and females. The Y-linked fshr allele, which included 24 nonsynonymous variants and showed a highly divergent 3D protein structure, was overexpressed in males compared to the X-linked allele at all stages of gonadal differentiation. We hypothesize a mechanism hampering the action of the follicle stimulating hormone driving the undifferentiated gonad toward testis. 相似文献
53.
54.
Ruth Meléndez Enrique Meléndez-Hevia Marta Cascante 《Journal of molecular evolution》1997,45(4):446-455
Optimization of molecular design in cellular metabolism is a necessary condition for guaranteeing a good structure–function
relationship. We have studied this feature in the design of glycogen by means of the mathematical model previously presented
that describes glycogen structure and its optimization function [Meléndez-Hevia et al. (1993), Biochem J 295: 477–483]. Our
results demonstrate that the structure of cellular glycogen is in good agreement with these principles. Because the stored
glucose in glycogen must be ready to be used at any phase of its synthesis or degradation, the full optimization of glycogen
structure must also imply the optimization of every intermediate stage in its formation. This case can be viewed as a molecular
instance of the eye problem, a classical paradigm of natural selection which states that every step in the evolutionary formation of a functional structure
must be functional. The glycogen molecule has a highly optimized structure for its metabolic function, but the optimization
of the full molecule has meaning and can be understood only by taking into account the optimization of each intermediate stage
in its formation.
Received: 23 October 1996 / Accepted: 21 April 1997 相似文献
55.
Acutely administered melatonin reduces oxidative damage in lung and brain induced by hyperbaric oxygen 总被引:3,自引:0,他引:3
Pablos Marta I.; Reiter Russel J.; Chuang Jin-Ing; Ortiz Genaro G.; Guerrero Juan M.; Sewerynek Ewa; Agapito Maria T.; Melchiorri Daniela; Lawrence Richard; Deneke Susan M. 《Journal of applied physiology》1997,83(2):354-358
Pablos, Marta I., Russel J. Reiter, Jin-Ing Chuang, GenaroG. Ortiz, Juan M. Guerrero, Ewa Sewerynek, Maria T. Agapito, DanielaMelchiorri, Richard Lawrence, and Susan M. Deneke. Acutely administered melatonin reduces oxidative damage in lung and brain induced by hyperbaric oxygen. J. Appl.Physiol. 83(2): 354-358, 1997.Hyperbaric oxygenexposure rapidly induces lipid peroxidation and cellular damage in avariety of organs. In this study, we demonstrate that the exposure ofrats to 4 atmospheres of 100% oxygen for 90 min is associated withincreased levels of lipid peroxidation products [malonaldehyde(MDA) and 4-hydroxyalkenals (4-HDA)] and withchanges in the activities of two antioxidative enzymes[glutathione peroxidase (GPX) and glutathione reductase (GR)], as well as in the glutathione status in the lungs and in the brain. Products of lipid peroxidation increased after hyperbaric hyperoxia, both GPX and GR activities were decreased, and levels oftotal glutathione (reduced+oxidized) and glutathione disulfide (oxidized glutathione) increased in both lung and brain areas (cerebralcortex, hippocampus, hypothalamus, striatum, and cerebellum) but not inliver. When animals were injected with melatonin (10 mg/kg) immediatelybefore the 90-min hyperbaric oxygen exposure, all measurements ofoxidative damage were prevented and were similar to those in untreatedcontrol animals. Melatonin's actions may be related to a variety ofmechanisms, some of which remain to be identified, including itsability to directly scavenge free radicals and its induction ofantioxidative enzymes via specific melatonin receptors. 相似文献
56.
Gracjana Klein Robert Walczak Ewa Krasnowska Adam Blaszczak Barbara Lipiska 《Molecular microbiology》1995,16(4):801-811
We have investigated heat-shock response in a marine bacterium Vibrio harveyi. We have found that 39 C was the highest tempature at which V. harveyi was able to grow steadily. A shift from 30° C to 39° C caused increased synthesis of at least 10 proteins, as judged by SDS-PAGE, with molecular masses of 90, 70, 58, 41, 31, 27, 22, 15, 14.5 and 14kDa. The 70, 58, 41 and 14.5 kDa proteins were immunologically homologous to DnaK, GroEL, DnaJ and GroES heat-shock proteins of Escherichia coli, respectively. V. harveyi GroES protein had a lower molecular mass (14.5 kDa) than E. coli GroES, migrating in SDS-PAGE as 15 kDa protein. We showed that a protein of ~43 kDa, immunologically reactive with antiserum against E. coli sigma 32 subunit (σ32) of RNA polymerase, was induced by heat-shock and co-purified with V. harveyi RNA polymerase. These results suggest that the 43 kDa protein is a heat-shock sigma protein of V. harveyi. Preparation containing the V. harveyi sigma 32 homologue, supplemented with core RNA polymerase of E. coli, was able to transcribe heat-shock promoters of E. coli in vitro. 相似文献
57.
We have studied the presence of a cloned fragment of DNA from Drosophila melanogaster in other organisms by means of nucleic acid hybridization analysis. The isolated region is localized in polytene chromosomes at the 63F subdivision. This region includes a puff that responds within minutes to ecdysone stimulation. We have found that 63F DNA from D. melanogaster hybridizes 'in situ' to both DNA and RNA from D. simulans, D. teissieri, and D. hydei. In all these species the isolated DNA remains associated with one early-ecdysone stimulated puff. The isolated Drosophila recombinant DNA is also complementary to polyadenylated RNA from foetal and adult rat liver but fails to hybridize to the nonpolyadenylated RNA classes from both sources and to polyadenylated RNA from rat mammary glands. 相似文献
58.
Marta Elisa Vázquez-Memije Alfonso Cárabez-Trejo Graciela Gallardo-Trillanes Graciela Delhumeau-Ongay 《Archives of biochemistry and biophysics》1984,232(2):441-449
Rat testis mitochondrial ATPase was not inhibited by oligomycin at pH 7.5. It was inhibited only at higher alkaline pH's, and showed a lower sensitivity both to oligomycin and N,N′-dicyclohexylcarbodiimide and a higher one to efrapeptin. In submitochondrial particles, testis ATPase was only slightly inhibited by oligomycin, ossamycin, and efrapeptin. The possibility of a loose binding of F1 to the membrane was supported by its recovery from the supernatant of the submitochondrial particles. Furthermore, by electron microscopy, after hypoosmotic shock and negative staining of the mitochondrial preparations, most of the inner mitochondrial membranes showed only a few “knobs” or none at all. The capacity of the testis mitochondrial preparation to produce ATP was tested and compared to that from liver. ATP synthetase/ATPase activity ratio was in liver mitochondria, whereas in the testis it was . In spite of this large difference, at least part of the testis ATPase must be firmly bound to the membrane, since it is able to form ATP. The rest seems to be loosely bound and its functional significance is still unknown. 相似文献
59.
In extracts obtained by treating rye embryo ribosomes with 0.5 M NH4Cl, nuclease activity was noted towards double-stranded RNA from virus of Penicillium chrysogenum and towards synthetic poly (A)-poly (U) and poly (I)-poly (C) complexes. 相似文献
60.
I. Marta Evans Ronald R. D. Croy Philippa Hutchinson Donald Boulter Peter I. Payne Margaret E. Gordon 《Planta》1979,144(5):455-462
Polyribosomes which have template activity in the wheat germ system have been isolated from developing pea seeds. Some of the translation products have identical mobilities to the vicilin and legumin subunits by SDS-PAGE. Certain products were specifically immunoprecipitated with antisera prepared against purified vicilin and legumin fractions. Various RNA fractions including poly A-rich RNA have also been isolated from polyribosomes and shown to direct the synthesis of polyripeptides whose properties are similar to the storage protein subunits. The results are discussed in relationship to other investigations with seed storage protein biosynthesis in vitro.Abbreviations DTT
dithiothreitol
- SDS-PAGE
SDS-polyacrylamide gel electrophoresis
- TCA
tricarboxylic acid 相似文献