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981.
Carlos Sanz-Garcia Gemma Ferrer-Mayorga águeda González-Rodríguez ángela M. Valverde Antonio Martín-Duce Juan P. Velasco-Martín Javier Regadera Margarita Fernández Susana Alemany 《The Journal of biological chemistry》2013,288(21):15342-15351
Cot/tpl2 (MAP3K8) activates MKK1/2-Erk1/2 following stimulation of the Toll-like/IL-1 receptor superfamily. Here, we investigated the role of Cot/tpl2 in sterile inflammation and drug-induced liver toxicity. Cot/tpl2 KO mice exhibited reduced hepatic injury after acetaminophen challenge, as evidenced by decreased serum levels of both alanine and aspartate aminotransferases, decreased hepatic necrosis, and increased survival relative to Wt mice. Serum levels of both alanine and aspartate aminotransferases were also lower after intraperitoneal injection of acetaminophen in mice expressing an inactive form of Cot/tpl2 compared with Wt mice, suggesting that Cot/tpl2 activity contributes to acetaminophen-induced liver injury. Furthermore, Cot/tpl2 deficiency reduced neutrophil and macrophage infiltration in the liver of mice treated with acetaminophen, as well as their hepatic and systemic levels of IL-1α. Intraperitoneal injection of damage-associated molecular patterns from necrotic hepatocytes also impaired the recruitment of leukocytes and decreased the levels of several cytokines in the peritoneal cavity in Cot/tpl2 KO mice compared with Wt counterparts. Moreover, similar activation profiles of intracellular pathways were observed in Wt macrophages stimulated with Wt or Cot/tpl2 KO damage-associated molecular patterns. However, upon stimulation with damage-associated molecular patterns, the activation of Erk1/2 and JNK was deficient in Cot/tpl2 KO macrophages compared with their Wt counterparts; an effect accompanied by weaker release of several cytokines, including IL-1α, an important component in the development of sterile inflammation. Taken together, these findings indicate that Cot/tpl2 contributes to acetaminophen-induced liver injury, providing some insight into the underlying molecular mechanisms. 相似文献
982.
Manuela Meireles Fátima Martel João Araújo Celestino Santos-Buelga Susana Gonzalez-Manzano Montserrat Dueñas Victor de Freitas Nuno Mateus Conceição Calhau Ana Faria 《The Journal of membrane biology》2013,246(9):669-677
The blood–brain barrier (BBB) plays a key role in limiting and regulating glucose access to glial and neuronal cells. In this work glucose uptake on a human BBB cell model (the hCMEC/D3 cell line) was characterized. The influence of some hormones and diet components on glucose uptake was also studied. 3H-2-deoxy-d-glucose ([3H]-DG) uptake for hCMEC/D3 cells was evaluated in the presence or absence of tested compounds. [3H]-DG uptake was sodium- and energy-independent. [3H]-DG uptake was regulated by Ca2+ and calmodulin but not by MAPK kinase pathways. PKC, PKA and protein tyrosine kinase also seem to be involved in glucose uptake modulation. Progesterone and estrone were found to decrease 3H-DG uptake. Catechin and epicatechin did not have any effect, but their methylated metabolites increased [3H]-DG uptake. Quercetin and myricetin decreased [3H]-DG uptake, and glucuronic acid-conjugated quercetin did not have any effect. These cells expressed GLUT1, GLUT3 and SGLT1 mRNA. 相似文献
983.
Maritza Sepúlveda Doris Oliva L. René Duran Alejandra Urra Susana N. Pedraza Patrícia Majluf Natalie Goodall Enrique A. Crespo 《Oecologia》2013,171(4):809-817
We tested the validity of Bergmann’s rule and Rosenzweig’s hypothesis through an analysis of the geographical variation of the skull size of Otaria flavescens along the entire distribution range of the species (except Brazil). We quantified the sizes of 606 adult South American sea lion skulls measured in seven localities of Peru, Chile, Uruguay, Argentina, and the Falkland/Malvinas Islands. Geographical and environmental variables included latitude, longitude, and monthly minimum, maximum, and mean air and ocean temperatures. We also included information on fish landings as a proxy for productivity. Males showed a positive relationship between condylobasal length (CBL) and latitude, and between CBL and the six temperature variables. By contrast, females showed a negative relationship between CBL and the same variables. Finally, female skull size showed a significant and positive correlation with fish landings, while males did not show any relationship with this variable. The body size of males conformed to Bergmann’s rule, with larger individuals found in southern localities of South America. Females followed the converse of Bergmann’s rule at the intraspecific level, but showed a positive relationship with the proxy for productivity, thus supporting Rosenzweig’s hypothesis. Differences in the factors that drive body size in females and males may be explained by their different life-history strategies. Our analyses demonstrate that latitude and temperature are not the only factors that explain spatial variation in body size: others such as food availability are also important for explaining the ecogeographical patterns found in O. flavescens. 相似文献
984.
Susana Magadán-Mompó Anastasia M. Zimmerman Christian Sánchez-Espinel Francisco Gambón-Deza 《Immunogenetics》2013,65(5):387-396
The gene segments encoding antibodies have been studied in many capacities and represent some of the best-characterized gene families in traditional animal disease models (mice and humans). To date, multiple immunoglobulin light chain (IgL) isotypes have been found in vertebrates and it is unclear as to which isotypes might be more primordial in nature. Sequence data emerging from an array of fish genome projects is a valuable resource for discerning complex multigene assemblages in this critical branch point of vertebrate phylogeny. Herein, we have analyzed the genomic organization of medaka (Oryzias latipes) IgL gene segments based on recently released genome data. The medaka IgL locus located on chromosome 11 contains at least three clusters of IgL gene segments comprised of multiple gene assemblages of the kappa light chain isotype. These data suggest that medaka IgL gene segments may undergo both intra- and inter-cluster rearrangements as a means to generate additional diversity. Alignments of expressed sequence tags to concordant gene segments which revealed each of the three IgL clusters are expressed. Collectively, these data provide a genomic framework for IgL genes in medaka and indicate that Ig diversity in this species is achieved from at least three distinct chromosomal regions. 相似文献
985.
Carolina Silva de Oliveira Neubern Susana Trivinho-Strixino 《Studies on Neotropical Fauna and Environment》2013,48(1):26-35
Two new species of Parapentaneura Stur, Fittkau et Serrano, 2006 (Diptera: Chironomidae: Tanypodinae) from southeastern Brazil are described and figured as male, pupa and larva: P. brunnescens and P. flavescens. Keys to the males, pupae and larvae of known species of Parapentaneura are provided.http://www.zoobank.org/urn:lsid:zoobank.org:pub:E6860EBE-B781-4DDA-9650-6E6EA3A0309E 相似文献
986.
A new species of Pelomus Reiss, 1989 (Diptera: Chironomidae: Chironominae), P. sophiae sp. n., is described and figured as male, pupa and larva. Diagnoses for male and pupa of the genus are emended. The larvae, reared in the laboratory to obtain all life stages, were collected on bottom sand of reservoir and ponds, in southeast Brazil. 相似文献
987.
Susana Manzano Cecilia Martínez Zoraida Megías Dolores Garrido Manuel Jamilena 《Journal of Plant Growth Regulation》2013,32(4):789-798
It is well established that ethylene is the main hormonal regulator of sexual expression in the Cucurbitaceae family, controlling not only the sexual fate of individual floral buds, but also the female flower transition, that is, the time at which the first female flower appears and therefore the number of female flowers per plant. Although sex determination of individual flower buds is known to be controlled by specific ethylene biosynthesis ACS genes in melon and cucumber, the role of ethylene genes in the control of the transition to female flowering is still unknown. We have identified two contrasting monoecious inbred lines of Cucurbita pepo, Bolognese (Bog) and Vegetable spaghetti (Veg), which differ in female flower transition but not in flower development. In Bog, which is very sensitive to ethylene, the transition to female flowering is very early, whereas in Veg, which is much less sensitive to ethylene, the transition occurs much later. In this article we compare the production of ethylene and the expression profiles of seven genes involved in the biosynthesis, perception, and signalling of ethylene in the two contrasting lines. Bog, with earlier female flower transition, showed higher ethylene production and CpACO1 expression in the apex at an earlier stage of plant development, when Bog is already producing female flowers, but Veg has not transitioned to female flowering yet. Moreover, the expression of the ethylene receptor and CTR-like genes in the apex of Veg and Bog plants indicates that these genes negatively regulate female flower transition during the earlier stages of plant development. The earlier transition to female flowering in Bog is not only associated with a higher production of ethylene in the apex but also with a premature decline of ethylene negative regulators (receptors and CTR-like) in the apex of the plant. These results provide the basis for a model that explains the regulation of female flowering transition in monoecious cucurbits. 相似文献
988.
Idalina Machado Joana Graça Ana Margarida Sousa Susana Patrícia Lopes 《Biofouling》2013,29(10):1151-1159
Antimicrobial residue deposition can change the physico-chemical properties of bacteria and surfaces and thus promote or impair bacterial adhesion. This study focuses on benzalkonium chloride (BC) deposition on polystyrene (PS) surfaces and the influence of this conditioning film on the physico-chemical properties of PS and on early adhesion and biofilm formation by Pseudomonas aeruginosa wild-type and its laboratory BC-adapted strain. The latter readily acquired the ability to grow in BC, and also exhibited physico-chemical surface changes. The existence of residues on PS surfaces altered their hydrophobicity and favoured adhesion as determined by the free energy and early adhesion characterization. Adapted bacteria revealed a higher ability to adhere to surfaces and to develop biofilms, especially on BC-conditioned surfaces, which thereby could enhance resistance to sanitation attempts. These findings highlight the importance of investigations concerning the antimicrobial deposition effect after cleaning procedures, which may encourage bacterial adhesion, especially of bacteria that have been previously exposed to chemical stresses. 相似文献
989.
990.
Metabolic pathways for the degradation of phosphatidic acid in isolated nuclei from cerebellar cells
The aim of the present research was to analyse the pathways for phosphatidic acid metabolism in purified nuclei from cerebellar cells. Lipid phosphate phosphatase and diacylglyceride lipase activities were detected in nuclei from cerebellar cells. It was observed that DAGL activity makes up 50% of LPP activity and that PtdOH can also be metabolised to lysophosphatidic acid. With a nuclear protein content of approximately 40 μg, the production of diacylglycerol and monoacylglycerol was linear for 30 min and 5 min, respectively, whereas it increased with PtdOH concentrations of up to 250 μM. LysoPtdOH, sphingosine 1-phosphate and ceramide 1-phosphate, which are alternative substrates for LPP, significantly reduced DAG production from PA. DAG and MAG production increased in the presence of Triton X-100 (1 mM) whereas no modifications were observed in the presence of ionic detergent sodium deoxycholate. Ca2+ and Mg2+ stimulated MAG production without affecting DAG formation whereas fluoride and vanadate inhibited the generation of both products. Specific PtdOH-phospholipase A1 and PtdOH-phospholipase A2 were also detected in nuclei. Our findings constitute the first reported evidence of active PtdOH metabolism involving LPP, DAGL and PtdOH-selective PLA activities in purified nuclei prepared from cerebellar cells. 相似文献