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951.
Iker Gmez-García Jenifer Trepiana Alfredo Fernndez-Quintela Marta Giralt María P. Portillo 《International journal of molecular sciences》2022,23(15)
The present narrative review gathers the studies reported so far, addressing sex differences in the effects of cold exposure, feeding pattern and age on brown adipose tissue (BAT) thermogenesis and white adipose tissue (WAT) browning. In rodents, when exposed to decreasing temperatures, females activate thermogenesis earlier. Results obtained in humans go in the same line, although they do not provide results as solid as those obtained in rodents. Regarding the effects of overfeeding, interesting sex differences on BAT thermogenic capacity have been reported, and the greater or lower sensitivity of each sex to this dietary situation seems to be dependent on the type of feeding. In the case of energy restriction, females are more sensitive than males. In addition, sex differences have also been observed in thermogenesis changes induced by phenolic compound administration. During sexual development, an increase in BAT mass and BAT activity takes place. This phenomenon is greater in boys than in girls, probably due to its relation to muscle-mass growth. The opposite situation takes place during ageing, a lifespan period where thermogenic capacity declines, this being more acute in men than in women. Finally, the vast majority of the studies have reported a higher susceptibility to developing WAT browning amongst females. The scarcity of results highlights the need for further studies devoted to analysing this issue, in order to provide valuable information for a more personalised approach. 相似文献
952.
Marta Po
niak Dominika ukowska Aleksandra Gdaj Mateusz Adam Krzycik Natalia Porbska Magorzata Zakrzewska Jacek Otlewski ukasz Opaliski 《International journal of molecular sciences》2022,23(15)
Precise anticancer therapies employing cytotoxic conjugates constitute a side-effect-limited, highly attractive alternative to commonly used cancer treatment modalities, such as conventional chemotherapy, radiotherapy or surgical interventions. Receptor tyrosine kinases are a large family of N-glycoproteins intensively studied as molecular targets for cytotoxic conjugates in various cancers. At the cell surface, these receptors are embedded in a dense carbohydrate layer formed by numerous plasma membrane glycoproteins. The complexity of the cell surface architecture is further increased by galectins, secreted lectins capable of recognizing and clustering glycoconjugates, affecting their motility and activity. Cell surface N-glycosylation is intensively remodeled by cancer cells; however, the contribution of this phenomenon to the efficiency of treatment with cytotoxic conjugates is largely unknown. Here, we evaluated the significance of N-glycosylation for the internalization and toxicity of conjugates targeting two model receptor tyrosine kinases strongly implicated in cancer: HER2 and FGFR1. We employed three conjugates of distinct molecular architecture and specificity: AffibodyHER2-vcMMAE (targeting HER2), vcMMAE-KCK-FGF1.E and T-Fc-vcMMAE (recognizing different epitopes within FGFR1). We demonstrated that inhibition of N-glycosylation reduced the cellular uptake of all conjugates tested and provided evidence for a role of the galectin network in conjugate internalization. In vitro binding studies revealed that the reduced uptake of conjugates is not due to impaired HER2 and FGFR1 binding. Importantly, we demonstrated that alteration of N-glycosylation can affect the cytotoxic potential of conjugates. Our data implicate a key role for cell surface N-glycosylation in the delivery of cytotoxic conjugates into cancer cells. 相似文献
953.
Laura Gmez-Jaramillo Ftima Cano-Cano Elena M. Snchez-Fernndez Carmen Ortiz Mellet Jos M. García-Fernndez Martín Alcal Fabiola lvarez-Gallego Marta Iturregui María del Carmen Gonzlez-Montelongo Antonio Campos-Caro Ana I. Arroba Manuel Aguilar-Diosdado 《International journal of molecular sciences》2022,23(15)
Inflammatory processes play a central role in the pathogenesis of diabetic nephropathy (DN) in the early stages of the disease. The authors demonstrate that the glycolipid mimetic (Ss)-DS-ONJ is able to abolish inflammation via the induction of autophagy flux and provokes the inhibition of inflammasome complex in ex vivo and in vitro models, using adult kidney explants from BB rats. The contribution of (Ss)-DS-ONJ to reducing inflammatory events is mediated by the inhibition of classical stress kinase pathways and the blocking of inflammasome complex activation. The (Ss)-DS-ONJ treatment is able to inhibit the epithelial-to-mesenchymal transition (EMT) progression, but only when the IL18 levels are reduced by the treatment. These findings suggest that (Ss)-DS-ONJ could be a novel, and multifactorial treatment for DN. 相似文献
954.
Cláudio Ananias Ferraz Vanessa Braganholo Marta Mattoso 《Journal of Web Semantics》2010,8(2-3):209-224
Active XML (AXML) documents combine extensional XML data with intentional data defined through Web service calls. The dynamic properties of these documents pose challenges to both storage and data materialization techniques. In this paper, we present ARAXA, a non-intrusive approach to store and manage AXML documents. We also define a methodology to materialize AXML documents at query time. The storage approach of ARAXA is based on plain relational tables and user-defined functions of Object-Relational DBMS to trigger the service calls. By using a DBMS we benefit from efficient storage tools and query optimization. Approaches without DBMS support have to process XML in main memory or provide for virtual memory solutions. One of the main advantages of ARAXA is that AXML documents do not need to be loaded into main memory at query processing time. This is crucial when dealing with large documents. The experimental results with ARAXA prototype show that our approach is scalable and capable of dealing with large AXML documents. 相似文献
955.
956.
Alicja Chrzanowska Aleksandra Drzewiecka-Antonik Katarzyna Dobrzyska Joanna Stefaska Piotr Pietrzyk Marta Struga Anna Bielenica 《International journal of molecular sciences》2021,22(21)
A series of eight copper (II) complexes with 3-(4-chloro-3-nitrophenyl)thiourea were designed and synthesized. The cytotoxic activity of all compounds was assessed in three human cancer cell lines (SW480, SW620, PC3) and human normal keratinocytes (HaCaT). The complexes 1, 3, 5, 7 and 8 were cytotoxic to the studied tumor cells in the low micromolar range, without affecting the normal cells. The complexes 1, 3, 7 and 8 induced lactate dehydrogenase (LDH) release in all cancer cell lines, but not in the HaCaT cells. They provoked early apoptosis in pathological cells, especially in SW480 and PC3 cells. The ability of compounds 1, 3, 7 and 8 to diminish interleukin-6 (IL-6) concentration in a cell was established. For the first time, the influence of the most promising Cu (II) complexes on intensities of detoxifying and reactive oxygen species (ROS) scavenging the enzymes of tumor cells was studied. The cytotoxic effect of all copper (II) conjugates against standard and hospital bacterial strains was also proved. 相似文献
957.
Ignacio Coln-Mesa Marta Fernndez-Galilea Neira Sinz Marta Lopez-Yus Jose M. Artigas Jos Miguel Arbons-Mainar Elisa Flix-Soriano Xavier Escot María Jesús Moreno-Aliaga 《International journal of molecular sciences》2021,22(21)
Aging usually comes associated with increased visceral fat accumulation, reaching even an obesity state, and favoring its associated comorbidities. One of the processes involved in aging is cellular senescence, which is highly dependent on the activity of the regulators of the cell cycle. The aim of this study was to analyze the changes in the expression of p27 and cdk2 in different adipose tissue depots during aging, as well as their regulation by obesity in mice. Changes in the expression of p27 and CDK2 in visceral and subcutaneous white adipose tissue (WAT) biopsies were also analyzed in a human cohort of obesity and type 2 diabetes. p27, but not cdk2, exhibits a lower expression in subcutaneous than in visceral WAT in mice and humans. p27 is drastically downregulated by aging in subcutaneous WAT (scWAT), but not in gonadal WAT, of female mice. Obesity upregulates p27 and cdk2 expression in scWAT, but not in other fat depots of aged mice. In humans, a significant upregulation of p27 was observed in visceral WAT of subjects with obesity. Taken together, these results show a differential adipose depot-dependent regulation of p27 and cdk2 in aging and obesity, suggesting that p27 and cdk2 could contribute to the adipose-tissue depot’s metabolic differences. Further studies are necessary to fully corroborate this hypothesis. 相似文献
958.
Damian Pawelski Alicja Walewska Sylwia Ksiezak Dariusz Sredzinski Piotr Radziwon Marcin Moniuszko Ramesh Gandusekar Andrzej Eljaszewicz Ryszard Lazny Krzysztof Brzezinski Marta E. Plonska-Brzezinska 《International journal of molecular sciences》2021,22(21)
Curcumin (CUR) is a natural compound that exhibits anti-inflammatory, anti-bacterial, and other biological properties. However, its application as an effective drug is problematic due to its poor oral bioavailability, solubility in water, and poor absorption from the gastrointestinal tract. The aim of this work is to synthesize monocarbonyl analogs of CUR based on the 9-methyl-9-azabicyclo[3.2.1]nonan-3-one (pseudopelletierine, granatanone) scaffold to improve its bioavailability. Granatane is a homologue of tropane, whose structure is present in numerous naturally occurring alkaloids, e.g., l-cocaine and l-scopolamine. In this study, ten new pseudopelletierine-derived monocarbonyl analogs of CUR were successfully synthesized and characterized by spectral methods and X-ray crystallography. Additionally, in vitro test of the cytotoxicity and anti-inflammatory properties of the synthesized compounds were performed. 相似文献
959.
Laura Bueso Marta Osorio‐Galindo Isabel Alcaina‐Miranda Amparo Ribes‐Greus 《应用聚合物科学杂志》2000,75(11):1424-1433
Novel hydrophobic composite membranes made of crosslinked poly(dimethylsiloxane) and poly(methyl hydrogen siloxane) (PDMS–PMHS) with various amounts of catalyst were prepared. Pervaporation experiments with water–ethanol mixtures revealed that an optimum ratio of catalyst to polymer base existed. Both swelling behavior and dynamic–mechanical properties of these silicone films were studied. The swelling experiments in different mixtures of ethanol and water determined that ethanol is preferentially sorbed and that the membranes are only capable to absorb a limited quantity of solvent. Equilibrium swelling data were also used in combination with the analysis of the viscoelastic relaxation of the swollen samples to obtain the dependence of the dynamic–mechanical properties of the silicone films on the quantity of permeants sorbed into the membrane. It was observed that the permselective parameters were related with the mobility of the chains and the free volume. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 75: 1424–1433, 2000 相似文献
960.
Luiz M. R. Gadelha Jr. Michael Wilde Marta Mattoso Ian Foster 《Distributed and Parallel Databases》2012,30(5-6):351-370
Scientific research is increasingly assisted by computer-based experiments. Such experiments are often composed of a vast number of loosely-coupled computational tasks that are specified and automated as scientific workflows. This large scale is also characteristic of the data that flows within such “many-task” computations (MTC). Provenance information can record the behavior of such computational experiments via the lineage of process and data artifacts. However, work to date has focused on lineage data models, leaving unsolved issues of recording and querying other aspects, such as domain-specific information about the experiments, MTC behavior given by resource consumption and failure information, or the impact of environment on performance and accuracy. In this work we contribute with MTCProv, a provenance query framework for many-task scientific computing that captures the runtime execution details of MTC workflow tasks on parallel and distributed systems, in addition to standard prospective and data derivation provenance. To help users query provenance data we provide a high level interface that hides relational query complexities. We evaluate MTCProv using an application in protein science, and describe how important query patterns such as correlations between provenance, runtime data, and scientific parameters are simplified and expressed. 相似文献