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91.
María Mena Alberto López-Luna Keiko Shirai Alberto Tecante Miquel Gimeno Eduardo Bárzana 《Bioprocess and biosystems engineering》2013,36(3):383-387
Hyperbranched poly-l-lactides have been synthesized by eROP in [C4MIM][PF6] media. The bis(hydroxymethyl)butyric acid molecule was used as the AB2 core co-monomer and immobilized lipase B from Candida antarctica as biocatalyst. The degree of branching could be controlled by the reaction conditions, with the maximum achieved being 0.21. The successful achievement of the hyperbranched structure is attributed to the high solvent power of substrates and products in the ionic liquid besides sustained lipase activity. 相似文献
92.
93.
Sofia Benfeito Catarina Oliveira Pedro Soares Carlos Fernandes Tiago Silva José Teixeira Fernanda Borges 《Mitochondrion》2013,13(5):427-435
The therapeutic potential of natural phenolic antioxidants in human diseases associated with oxidative damage has received great attention to date. Appraisal of literature evidences that, in general, antioxidant therapy has enjoyed relative successes in preclinical studies but little benefits in human intervention studies or clinical trials. In fact, despite the huge, largely untapped potential therapeutic benefit of natural phenolic antioxidants, such as vitamins, non-flavonoid and flavonoid compounds, they appear not to be suitable drug candidates. The problem may be related, among others, to their non-drug-likeness properties. Though controversial the results obtained so far confirm the importance of exploring phenolic natural systems as safe templates for the design of new antioxidants. To support the assumption an outlook of the lead structural optimization process to improve ADME properties was given by means of natural hydroxycinnamic acids as a case study. The optimization of drug physicochemical properties and the development of appropriate delivery antioxidant systems can provide in the next future a way out to attain effective therapeutic antioxidant agents. 相似文献
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95.
We have previously identified Usp46, which encodes for ubiquitin-specific peptidase 46, as a quantitative trait gene affecting the immobility time of mice in the tail suspension test (TST) and forced swimming test. The mutation that we identified was a 3-bp deletion coding for lysine (Lys 92), and mice with this mutation (MT mice), as well as Usp46 KO mice exhibited shorter TST immobility times. Behavioral pharmacology suggests that the gamma aminobutyric acid A (GABAA) receptor is involved in regulating TST immobility time. In order to understand how far Usp46 controls behavioral phenotypes, which could be related to mental disorders in humans, we subjected Usp46 MT and KO mice to multiple behavioral tests, including the open field test, ethanol preference test, ethanol-induced loss of righting reflex test, sucrose preference test, novelty-suppressed feeding test, marble burying test, and novel object recognition test. Although behavioral phenotypes of the Usp46 MT and KO mice were not always identical, deficiency of Usp46 significantly affected performance in all these tests. In the open field test, activity levels were lower in Usp46 KO mice than wild type (WT) or MT mice. Both MT and KO mice showed lower ethanol preference and shorter recovery times after ethanol administration. Compared to WT mice, Usp46 MT and KO mice exhibited decreased sucrose preference, took longer latency periods to bite pellets, and buried more marbles in the sucrose preference test, novelty-suppressed feeding test, and marble burying test, respectively. In the novel object recognition test, neither MT nor KO mice showed an increase in exploration of a new object 24 hours after training. These findings indicate that Usp46 regulates a wide range of behavioral phenotypes that might be related to human mental disorders and provides insight into the function of USP46 deubiquitinating enzyme in the neural system. 相似文献
96.
Takeo Kawahara Naoe Hotta Yukiko Ozawa Seiichi Kato Keiko Kano Yukihiro Yokoyama Masato Nagino Takashi Takahashi Kiyoshi Yanagisawa 《PloS one》2013,8(12)
Elucidation of how pancreatic cancer cells give rise to distant metastasis is urgently needed in order to provide not only a better understanding of the underlying molecular mechanisms, but also to identify novel targets for greatly improved molecular diagnosis and therapeutic intervention. We employed combined proteomic technologies including mass spectrometry and isobaric tags for relative and absolute quantification peptide tagging to analyze protein profiles of surgically resected human pancreatic ductal adenocarcinoma tissues. We identified a protein, dihydropyrimidinase-like 3, as highly expressed in human pancreatic ductal adenocarcinoma tissues as well as pancreatic cancer cell lines. Characterization of the roles of dihydropyrimidinase-like 3 in relation to cancer cell adhesion and migration in vitro, and metastasis in vivo was performed using a series of functional analyses, including those employing multiple reaction monitoring proteomic analysis. Furthermore, dihydropyrimidinase-like 3 was found to interact with Ezrin, which has important roles in cell adhesion, motility, and invasion, while that interaction promoted stabilization of an adhesion complex consisting of Ezrin, c-Src, focal adhesion kinase, and Talin1. We also found that exogenous expression of dihydropyrimidinase-like 3 induced activating phosphorylation of Ezrin and c-Src, leading to up-regulation of the signaling pathway. Taken together, the present results indicate successful application of combined proteomic approaches to identify a novel key player, dihydropyrimidinase-like 3, in pancreatic ductal adenocarcinoma tumorigenesis, which may serve as an important biomarker and/or drug target to improve therapeutic strategies. 相似文献
97.
Camila Satie Savada Moema Cristina Costa de Lima Mário Luís Orsi Fernanda Simões de Almeida 《Zeitschrift fur angewandte Ichthyologie》2020,36(6):825-829
Ten microsatellite loci were developed and described for Pimelodus microstoma, identified in eggs collected from the lower Das Cinzas river. Nine loci were polymorphic, with 02–19 alleles per locus. The observed heterozygosity values were up to 0.898. Five species of the Pimelodidae family were also tested for amplification of loci, among which Pimelodus maculatus was the most successful in the transferability of primers. These loci have proven to be useful for studying the variability and structuring of populations of Pimelodus microstoma. 相似文献
98.
Hudson T. Pinheiro Bruno C. L. Macena Ronaldo B. Francini-Filho Carlos E. L. Ferreira Fernanda V. Albuquerque Natalia P. A. Bezerra Alfredo Carvalho-Filho Romulo C. P. Ferreira Osmar J. Luiz Thayna J. Mello Sibele A. Mendonça Diogo M. Nunes Caio R. Pimentel Alessandra M. A. Pires Abilio Soares-Gomes Danielle L. Viana Fabio H. V. Hazin Luiz A. Rocha 《Journal of fish biology》2020,97(4):1143-1153
Saint Peter and Saint Paul's Archipelago (SPSPA), one of the smallest and most isolated island groups in the world, is situated on the Mid-Atlantic Ridge, between Brazil and the African continent. SPSPA has low species richness and high endemism; nonetheless, the diversity of fishes from deep habitats (>30 m depth) had not been previously studied in detail. Several expeditions conducted between 2009 and 2018 explored the shallow and deep reefs of SPSPA using scuba, closed-circuit rebreathers, manned submersibles, baited remote underwater stereo-videos (stereo-BRUV) and fishing between 0 and 1050 m depth. These expeditions yielded 41 new records of fishes for SPSPA: 9 in open waters, 9 in shallow waters (0–30 m), 8 in mesophotic ecosystems (30–150 m) and 15 in deeper reefs (>150 m). Combined with literature records of adult pelagic, shallow and deep-reef species, as well as larvae, the database of the fish biodiversity for SPSPA currently comprises 225 species (169 recorded as adult fishes and 79 as larvae, with 23 species found in both stages). Most of them (112) are pelagic, 86 are reef-associated species and 27 are deep-water specialists. Species accumulation curves show that the number of fish species has not yet reached an asymptote. Whereas the number of species recorded in SPSPA is similar to that in other oceanic islands in the Atlantic Ocean, the proportion of shorefishes is relatively lower, and the endemism level is the third highest in the Atlantic. Twenty-nine species are listed as threatened with extinction. Observations confirm the paucity of top predators on shallow rocky reefs of the island, despite the presence of several pelagic shark species around SPSPA. Because all of the endemic species are reef associated, it is argued that the new marine-protected areas created by the Brazilian government do not ensure the protection and recovery of SPSPA's biodiversity because they allow exploitation of the most vulnerable species around the archipelago itself. This study suggests a ban on reef fish exploitation inside an area delimited by the 1000 m isobath around the islands (where all known endemics are concentrated) as the main conservation strategy to be included in the SPSPA management plan being prepared by the Brazilian government. 相似文献
99.
Katayama Kazuhiro Hosui Atsushi Sakai Yoshiyuki Itou Minoru Matsuzaki Yasushi Takamori Yoriyuki Hosho Keiko Tsuru Tomomi Takikawa Yasuhiro Michitaka Kojiro Ogawa Eishin Miyoshi Yoko Ito Toshifumi Ida Shinobu Hamada Izumi Miyoshi Katsunori Kodama Hiroko Takehara Tetsuo 《Biological trace element research》2020,195(1):71-81
Biological Trace Element Research - The essential trace element zinc maintains liver functions. Liver diseases can alter overall zinc concentrations, and hypozincemia is associated with various... 相似文献
100.
Maranhão Fernanda Cristina de Albuquerque Mendonça Nayara Maciel Teixeira Thamires Costa Lages Gilvonete Alves da Costa Sobrinha de Melo Jacqueline Araújo Porciuncula Carlos Guilherme Gaelzer da Silva Filho Eurípedes Alves Silva Denise Maria Wanderlei 《Mycopathologia》2020,185(3):537-543
Mycopathologia - Candida species are common in the human oral microbiota and may cause oral candidiasis (OC) when the microbiota equilibrium is disturbed. Immunosuppressed individuals are... 相似文献