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71.
Kathryn A. Ayres James T. Ketchum Rogelio González-Armas Felipe Galván-Magaña Alex Hearn Fernando R. Elorriaga-Verplancken Edgar M. Hoyos-Padilla Stephen M. Kajiura 《Journal of fish biology》2021,99(5):1735-1740
Cabo Pulmo National Park was established in 1995 and has since seen a large increase in fish biomass. An unoccupied aerial vehicle (UAV) was used to survey shallow coastal habitat in which lemon sharks (Negaprion brevirostris), bull sharks (Carcharhinus leucas) and Pacific nurse sharks (Ginglymostoma unami) were recorded. Sharks were more common in the afternoon, potentially using warmer shallow areas to behaviourally thermoregulate. This study highlights UAV surveying to be a viable tool for species identification, a limitation of previous terrestrial surveys conducted in the area. 相似文献
72.
73.
Daniel R. Henríquez Felipe J. Bodaleo Carolina Montenegro-Venegas Christian González-Billault 《PloS one》2012,7(12)
Microtubule-associated protein 1B (MAP1B) is a neuronal protein involved in the stabilization of microtubules both in the axon and somatodendritic compartments. Acute, genetic inactivation of MAP1B leads to delayed axonal outgrowth, most likely due to changes in the post-translational modification of tubulin subunits, which enhances microtubule polymerization. Furthermore, MAP1B deficiency is accompanied by abnormal actin microfilament polymerization and dramatic changes in the activity of small GTPases controlling the actin cytoskeleton. In this work, we showed that MAP1B interacts with a guanine exchange factor, termed Tiam1, which specifically activates Rac1. These proteins co-segregated in neurons, and interact in both heterologous expression systems and primary neurons. We dissected the molecular domains involved in the MAP1B-Tiam1 interaction, and demonstrated that pleckstrin homology (PH) domains in Tiam1 are responsible for MAP1B binding. Interestingly, only the light chain 1 (LC1) of MAP1B was able to interact with Tiam1. Moreover, it was able to increase the activity of the small GTPase, Rac1. These results suggest that the interaction between Tiam1 and MAP1B, is produced by the binding of LC1 with PH domains in Tiam1. The formation of such a complex impacts on the activation levels of Rac1 confirming a novel function of MAP1B related with the control of small GTPases. These results also support the idea of cross-talk between cytoskeleton compartments inside neuronal cells. 相似文献
74.
Wendy González Leandro Zú?iga L. Pablo Cid Barbara Arévalo María Isabel Niemeyer Francisco V. Sepúlveda 《The Journal of biological chemistry》2013,288(8):5984-5991
Proton-gated TASK-3 K+ channel belongs to the K2P family of proteins that underlie the K+ leak setting the membrane potential in all cells. TASK-3 is under cooperative gating control by extracellular [H+]. Use of recently solved K2P structures allows us to explore the molecular mechanism of TASK-3 cooperative pH gating. Tunnel-like side portals define an extracellular ion pathway to the selectivity filter. We use a combination of molecular modeling and functional assays to show that pH-sensing histidine residues and K+ ions mutually interact electrostatically in the confines of the extracellular ion pathway. K+ ions modulate the pKa of sensing histidine side chains whose charge states in turn determine the open/closed transition of the channel pore. Cooperativity, and therefore steep dependence of TASK-3 K+ channel activity on extracellular pH, is dependent on an effect of the permeant ion on the channel pHo sensors. 相似文献
75.
A Ph.D. dissertation completed by E.D. Cashatt in 1968 entitled “Revision of the Chrysauginae of North America” does not meet the criteria of publication so the new taxa described therein are not available per the International Code of Zoological Nomenclature. In order to validate the taxa proposed in that document we formally describe and illustrate the following: Arta brevivalvalis Cashatt, sp. n.,
Heliades lindae Cashatt, sp. n.,
Paragalasa Cashatt, gen. n., Paragalasa exospinalis Cashatt, sp. n., and Penthesilea sacculalis baboquivariensis Cashatt, subsp. n. We summarize other taxonomic actions proposed in the dissertation and those proposed by subsequent authors. We provide the current nomenclatural status with the literature citation of the paper in which the current status was proposed. A lectotype is designated for Clydonopteran tecomae. Adult holotypes and associated labels, and genitalia of paratypes are newly illustrated. 相似文献
76.
Early detection of atherosclerosis is of major importance to reduce the increased incidence of cardiovascular (CV) complications observed in patients with rheumatoid arthritis (RA). Prospective studies have shown that an abnormally increased carotid intima-media thickness and the presence of plaques assessed by carotid ultrasound are good markers to predict the development of CV events in these patients. Age, classic CV risk factors, and corticosteroid use are also predictors of new plaque formation in patients with RA. Active treatment of the disease may decrease the inflammatory burden, leading to a reduction in the progression of subclinical atherosclerosis in these patients. 相似文献
77.
Julia Spencer Barthold Jobayer Hossain Alicia Olivant‐Fisher Anita Reilly T. Ernesto Figueroa Ahmad BaniHani Jennifer Hagerty Ricardo González Paul H. Noh Jeanne M. Manson 《Birth defects research. Part A, Clinical and molecular teratology》2012,94(11):900-907
BACKGROUND : Genetic and environmental factors likely influence susceptibility to nonsyndromic cryptorchidism, a common disease presenting at birth or in later childhood. We compared cases and controls to define differential risk factors for congenital versus acquired cryptorchidism. METHODS : We compared questionnaire and clinical data from cases of congenital cryptorchidism (n = 230), acquired cryptorchidism (n = 182) and hernia/hydrocele (n = 104) with a group of healthy male controls (n = 358). Potential predictor variables (p < 0.2 in univariable analysis) were included in stepwise multivariable logistic regression models. RESULTS : Temporary (odds ratio [OR], 0.5; 95% confidence interval [CI], 0.4–0.8) or exclusive (OR, 0.6; 95% CI, 0.4–0.9) breastfeeding was reduced and soy formula feeding increased (OR, 1.8; 95% CI, 1.2–2.9) in acquired but not congenital or hernia/hydrocele groups. The highest risk estimates were observed for primary soy formula feeding with limited or no breastfeeding (OR 2.5; 95% CI, 1.4–4.3; adjusted OR, 2.7; 95% CI, 1.4–5.4) in the acquired group. Primary feeding risk estimates were equivalent or strengthened when multivariable models were limited to age greater than 2 years, full‐term or not small for gestational age, or Caucasian subjects. Pregnancy complications and increased maternal exposure to cosmetic or household chemicals were not consistently associated with either form of cryptorchidism in these models. CONCLUSIONS : Our data support reduced breastfeeding and soy formula feeding as potential risk factors for acquired cryptorchidism. Although additional studies are needed, hormonally active components of breast milk and soy formula could influence the establishment of normal testis position in the first months of life, leading to apparent ascent of testes in childhood. Birth Defects Research (Part A), 2012. © 2012 Wiley Periodicals, Inc. 相似文献
78.
María Elena González-Benito Carolina Kremer Miguel A. Ibáñez Carmen Martín 《Plant Cell, Tissue and Organ Culture》2016,127(2):359-368
The effect of antioxidants applied in one step of a cryopreservation protocol by encapsulation–dehydration on recovery and genetic stability of mint shoot tips has been studied. Glutathione (0.16 or 0.24 mM), ascorbic acid (0.28 or 0.43 mM) and α-tocopherol (vitamin E) were added to the preculture medium (0.3 M sucrose). DNA was extracted from three different types of samples: leaves from shoots, callus at the base of shoots and callus. RAPD and AFLP markers were used to assess the genetic stability. The use of antioxidants did not improve recovery after cryopreservation. One of the genotypes, ‘MEN 198’, showed higher percentage of stable samples than the other one, ‘MEN 186’ (56 vs. 37?%; considering all treatments and types of explant). The use of vitamin E improved the percentage of stable samples with respect to control treatment (no antioxidant) in ‘MEN 186’. No differences in the percentages of stable samples were observed among cryopreserved and non-cryopreserved (treated similarly without immersion in liquid nitrogen) plant material. Recovered shoots of both genotypes showed higher stability (76–80?% stable samples) than callus samples (14–22?%). 相似文献
79.
Maria Rosa Buemi Laura De Luca Alba Chimirri Stefania Ferro Rosaria Gitto Julio Alvarez-Builla Ramon Alajarin 《Bioorganic & medicinal chemistry》2013,21(15):4575-4580
Several indole derivatives, that were highly potent ligands of GluN2B-subunit-containing N-methyl-d-aspartate (NMDA) receptor, also demonstrated antioxidant properties in ABTS method. In particular, the 2-(4-benzylpiperidin-1-yl)-1-(5-hydroxy-1H-indol-3-yl)ethanone (1) proved to be a dual-effective neuroprotective agent. With the aim to increase the antioxidant properties we added a catechol moiety onto piperidine moiety. The designed hybrid derivative 3,4-dihydroxy-N-[1-[2-(5-hydroxy-1H-indol-3-yl)-2-oxoethyl]piperidin-4-yl]benzamide (10) was the most effective antioxidant agent (>94.1 ± 0.1% of inhibition at 17 μM) and showed GluN2B/NMDA receptor affinity at low micromolar concentration (IC50 0.66 μM). By means of computational studies we explored the effect of the presence of this antioxidant fragment during the recognition process to binding pocket. 相似文献
80.
Marcela Aida González María del Carmen Contini Nestor Millen Stella Teresita Mahieu 《Cell biochemistry and function》2012,30(8):701-708
The process of regenerating liver is the result of a balance between stimulating factors and inhibitors of hepatocyte proliferation. Melatonin and its metabolites have been found to protect tissues against oxidative damage generated by a variety of toxic agents and metabolic processes. Furthermore, studies in liver of rats showed a decrease in the liver mitochondrial hydroxylation of drugs returning to the normal state after the administration of antioxidants. This study was designed to determine, in experimental animals, whether the administration of an antioxidant agent such as melatonin could prevent cells events leading to tissue injury and hepatic dysfunction after partial hepatectomy (PH). Biliary flow (BF), oxidative stress in hepatic tissue and Na+/K+ATPase activities in whole plasma membrane were determined. PH decreased the Na+/K+ATPase activity. PH significantly reduced the BF (36%) and promoted oxidative stress with an increase of lipoperoxidation and decrease of glutathione peroxidase and catalase activities. Treatment with melatonin prevented the decrease of BF in rats with hepatectomy and normalized the Na+/K+ATPase activity. Moreover, melatonin markedly attenuated oxidative stress produced by PH. This may be the results of the higher efficacy of melatonin in scavenging various free radicals and also because of its ability in stimulating the antioxidant enzymes. We suggest that oxidative stress before and during liver regeneration has a crucial role in cholestasis, apoptotic/necrotic hepatocellular damage and the impairment in liver transport function induced by PH and that melatonin could modulate the degree of oxidative stress and through it prevent the alterations in liver function carrier. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献