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951.
Elizabeth G. Ibarra-Coronado Javier Velazquéz-Moctezuma Daniel Diaz Luis Enrique Becerril-Villanueva Lenin Pavón Jorge Morales-Montor 《International journal of biological sciences》2015,11(8):901-912
Sleep is considered an important predictor of immunity. A lack of sleep may reduce immunity, which increases susceptibility to any type of infection. Moreover, sleep deprivation in humans produces changes in both, the percent of circulating immune cells (T cells and NK cells) and cytokine levels (IL-1, IFNγ, TNΦ-αα, IL-6 and IL-17). The aim of our study was to investigate whether sleep deprivation produces deregulation on immune variables during the immune response generated against the helminth parasite Trichinella spiralis. Because sleep deprivation is stressful per se, we designed another experiments to compared stress alone (consisting in movement restriction and single housing) with sleep deprivation, in both control (uninfected) and experimental (infected) rats. Our results demonstrate that the sleep deprivation and stress have a differential effect in mesenteric lymph nodes (MLN) and spleen. In uninfected rats sleep deprivation alone produces an increase in natural killer cells (NK+) and B cells (CD45+), accompanied by a decrease in cytotoxic T cells (CD3+CD8+) in spleen; while, in MLN, produces only an increase in natural killer cells (NK+). Both, SD and stress, produce an increased percentage of total T cells (CD3+) in spleen. In the MLN both are also associated to an increase in cytotoxic T cells (CD3+CD8+) and B cells (CD45+). In the spleens of parasitized rats, cell populations did not change. In spleens of both, sleep-deprived and stressed infected rats, we observed an increase in B cells (CD45+). In infected rats, sleep deprivation alone produced an increase in NK cells (NK+). In mesenteric node cell populations of parasitized rats, we observed a decrease in NK cells and an increase in T helper (CD4+) cells in both SD and stressed rats. Rats that were only subjected to stress showed a decrease in B cells (CD45+). These findings suggest that the immune response generated against infection caused by T. spiralis is affected when the sleep pattern is disrupted. These results support the notion that sleep is a fundamental process for an adequate and strong immune response generated against this parasite. 相似文献
952.
Production of trichodiene by Trichoderma harzianum alters the perception of this biocontrol strain by plants and antagonized fungi
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Mónica G. Malmierca Susan P. McCormick Rosa E. Cardoza Nancy J. Alexander Enrique Monte Santiago Gutiérrez 《Environmental microbiology》2015,17(8):2628-2646
Trichothecenes are phytotoxic sesquiterpenic mycotoxins that can act as virulence factors in plant diseases. Harzianum A (HA) is a non‐phytotoxic trichothecene produced by Trichoderma arundinaceum. The first step in HA biosynthesis is the conversion of farnesyl diphosphate to trichodiene (TD), a volatile organic compound (VOC), catalysed by a sesquiterpene synthase encoded by the tri5 gene. Expression of tri5 in the biocontrol strain Trichoderma harzianum CECT 2413 resulted in production of TD in parallel with a reduction of ergosterol biosynthesis and an unexpected increase in the level of squalene. Transformants expressing tri5 displayed low chitinase activity and induced expression of Botrytis cinerea BOT genes, although their total antagonistic potential against phytopathogenic fungi was not reduced. VOCs released by the tri5‐transformant induced expression of tomato defence genes related to salicylic acid (SA), and TD itself strongly induced the expression of SA‐responsive genes and reduced the development of lateral roots. Together, these results suggest that TD acts as a signalling VOC in the interactions of Trichoderma with plants and other microorganisms by modulating the perception of this fungus to a given environment. Moreover, the TD ability to induce systemic defences indicates that complex trichothecene structures may not be necessary for inducing such responses. 相似文献
953.
Jesús Espinal-Enríquez Said Mu?oz-Montero Ivan Imaz-Rosshandler Aldo Huerta-Verde Carmen Mejía Enrique Hernández-Lemus 《BMC genomics》2015,16(1)
Background
Thyroid cancer (TC) is the most common malignant cancer of the Endocrine System. Histologically, there are three main subtypes of TC: follicular, papillary and anaplastic. Diagnosing a thyroid tumor subtype with a high level of accuracy and confidence is still a difficult task because genetic, molecular and cellular mechanisms underlying the transition from differentiated to undifferentiated thyroid tumors are not well understood.A genome-wide analysis of these three subtypes of thyroid carcinoma was carried out in order to identify significant differences in expression levels as well as enriched pathways for non-shared molecular and cellular features between subtypes.Results
Inhibition of matrix metalloproteinases pathway is a major event involved in thyroid cancer progression and its dysregulation may result crucial for invasiveness, migration and metastasis. This pathway is drastically altered in ATC while in FTC and PTC, the most important pathways are related to DNA-repair activation or cell to cell signaling events.Conclusion
A progression from FTC to PTC and then to ATC was detected and validated on two independent datasets. Moreover, PTX3, COLEC12 and PDGFRA genes were found as possible candidates for biomarkers of ATC while GPR110 could be tested to distinguish PTC over other tumor subtypes. The genome-wide analysis emphasizes the preponderance of pathway-dysregulation mechanisms over simple gene-malfunction as the main mechanism involved in the development of a cancer phenotype.Electronic supplementary material
The online version of this article (doi:10.1186/s12864-015-1372-0) contains supplementary material, which is available to authorized users. 相似文献954.
The effect of recreational SCUBA divers on the structural complexity and benthic assemblage of a Caribbean coral reef 总被引:1,自引:0,他引:1
955.
956.
Maite Beltrán Marta Maseda Yolanda Pérez Jordi Robles Enrique Pedroso Anna Grandas 《Nucleosides, nucleotides & nucleic acids》2013,32(7-9):1487-1488
Abstract Hydroxylated amino acids can be introduced in nucleopeptides using the acetyl group for their side chain protection. Base-stable nucleopeptide analogues are obtained if homoserine is used as the linking residue. 相似文献
957.
Verónica Fasulo ZhiQiang Zhang Edwin R. Price Juan G. Chediack William H. Karasov Enrique Caviedes-Vidal 《Comparative biochemistry and physiology. Part A, Molecular & integrative physiology》2013,164(1):71-76
Water-soluble nutrients are absorbed by the small intestine via transcellular and paracellular processes. The capacity for paracellular absorption seems lower in nonfliers than in fliers, although that conclusion rests largely on a comparison of relatively larger nonflying mammals (> 155 g) and relatively smaller flying birds (< 155 g). We report on paracellular absorption in laboratory mice, the smallest nonflying mammal species studied to date. Using a standard pharmacokinetic technique, we measured the extent of absorption (fractional absorption = f) of inert carbohydrate probes: l-arabinose (Mr = 150.13 Da) and cellobiose (342.3) that are absorbed exclusively by the paracellular route, and 3-O-methyl d-glucose (3OMD-glucose) (Mr = 194) absorbed both paracellularly and transcellularly. f was measured accurately in urine collection trials of 5–10 h duration. Absorption of 3OMD-glucose by mice was essentially complete (f = 0.95 ± 0.07) and much higher than that for l-arabinose (f = 0.21 ± 0.02), indicating that in mice, like other nonflying mammals, > 80% of glucose is absorbed by mediated process(es) rather than the passive, paracellular route. As in all other vertebrates, absorption of cellobiose (f = 0.13 ± 0.02) was even lower than that for l-arabinose, suggesting an equivalent molecular size cut-off for flying and nonflying animals and thus a comparable effective TJ aperture. An important ecological implication is that smaller water-soluble plant secondary metabolites that have been shown to be absorbed by the paracellular path in cell culture, such as phenolics and alkaloids, might be absorbed in substantial amounts by bats and small birds relative to nonflying mammals such as mice. 相似文献
958.
Enrique J. JareÑo JoaquÍn Romá Belén Romero Nuria MarÍn MarÍa Muriach Siv Johnsen 《Free radical research》2013,47(3):341-344
Serum malondialdehyde (MDA) levels are increased in human immunodeficiency virus (HIV)-infected children, as it happens also in infected adult individuals. Introduction of high activity antiretroviral therapy (HAART) has promoted an intense decline in morbidity and mortality of these patients. Here we present data on the effect of HAART on serum MDA of HIV+ children and compare them with levels prior to HAART. MDA levels reflect, as other markers do, the HAART-induced clinical improvement and probably also the pro-oxidant/antioxidant side effects of the different drugs used. The results herein allow the proposal of including serum MDA levels as an additional parameter for the clinical management of HIV+ children. 相似文献
959.
Mauro Belleggia Jorge Colonello Federico Cortés Daniel Enrique Figueroa 《Journal of fish biology》2021,99(5):1591-1601
This work examined the diet of the porbeagle shark Lamna nasus in the south-west Atlantic Ocean (SWAO, Argentina, 52° S–56° S) by analysing the stomach content information obtained by scientific observers who sampled specimens captured as by-catch on-board commercial fishing vessels from 2010 to 2020. A total of 148 fishing sites were analysed, in which the estimated catch was composed mainly of hoki Macruronus magellanicus (56.00%) and southern blue whiting Micromesistius australis (33.13%). From 413 porbeagle sharks sampled (292 females and 121 males) ranging from 71 to 241 cm total length (LT) (mean: 179.76 ± 26.74 cm), 310 (75.06%) contained food in the stomachs. The forage fish were mainly hoki M. magellanicus (23.53%) and southern blue whiting M. australis (19.05%), followed by the Patagonian sprat Sprattus fuegensis (4.48%) and nototheniids (1.4%). Cephalopods and crustaceans accounted for 10% of the diet. The estimated trophic level was 4.35. Generalized linear models revealed that the consumption of hoki M. magellanicus and southern blue whiting M. australis increased with the LT of the porbeagle shark. Moreover, smaller porbeagle sharks preyed upon both small and large teleost fish, whereas larger porbeagle sharks predated exclusively upon large fish. The diet of porbeagle shark involved interactions with fisheries as it fed upon the fish species that constituted the main catch in the analysed fishing sites, as well as the main catches of the austral trawl fisheries. The ecological role of porbeagle shark observed in the SWAO exposed implications for fisheries management from a multispecies perspective. 相似文献
960.
BioControl - Augmentative biological control has experienced a remarkable success, particularly in protected crops. Yet integrated pest management (IPM) still requires corrective treatments to... 相似文献