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951.
Einar Vargas-Bello-Pérez Gonzalo Íñiguez-González Nathaly Cancino-Padilla Juan J. Loor Philip C. Garnsworthy 《Archives of animal nutrition》2016,70(4):322-332
The aim of this study was to elucidate the effect of dietary supplementation of soybean oil (SO) and hydrogenated palm oil (HPO) on the transport of fatty acids (FA) within plasma lipoproteins in lactating and non-lactating cows. Three lactating and three non-lactating Holstein cows were used in two different 3 × 3 Latin square experiments that included three periods of 21 d. Dietary treatments for lactating cows consisted of a basal diet (control; no fat supplement) and fat-supplemented diets containing SO (500 g/d per cow) or HPO (500 g/d per cow). For non-lactating cows, dietary treatments consisted of a basal diet (control; no fat supplement) and fat-supplemented diets containing SO (170 g/d per cow) or HPO (170 g/d per cow). Compared with the control and SO diet, HPO addition increased (p < 0.05) the concentration of C16:0, C18:0, C18:2cis-9,12, C18:3cis-9,12,15 and total saturated and polyunsaturated FA in the plasma of lactating cows. In non-lactating cows, the SO addition increased the plasma concentration of C18:1trans-11. In lactating cows, concentrations of C16:0, C18:0 and total saturated FA were increased (p < 0.05) by HPO addition in the high-density lipoprotein (HDL). Total saturated FA were increased (p < 0.05) by HPO in very-low-density lipoprotein (VLDL). In non-lactating cows, the concentration of C18:0 was increased (p < 0.05) by HPO in HDL, whereas C18:1trans-11 was increased (p < 0.05) by SO in the low-density lipoprotein. Overall, it was found that distribution and transport of FA within the bovine plasma lipoproteins may be influenced by chain length and degree of unsaturation of dietary lipids. Also, the distribution of individual FA isomers such as C18:1trans-11 and C18:2cis-9,trans-11 may vary depending on the physiological state of the cow (lactating or non-lactating), and are increased in plasma (lactating cows) and the HDL (non-lactating cows) when cows are fed SO. 相似文献
952.
The clam Neilonella sulculata is the dominant bivalve on muddy bottoms along the Argentine continental shelf (Southwest Atlantic). The medusa stage of the hydroid Bougainvillia macloviana is one of the most abundant species in the gelatinous zooplankton of the Magellan region. Two benthic surveys carried out in 2007 and 2009 in San Jorge Gulf gave us the opportunity to analyse (1) the interaction between N. sulculata and its epibiont, B. macloviana, and (2) the role of the clam as hard substrate in a depositional area characterized by silt/clay sediments. Bougainvillia macloviana has a high prevalence on the posterior region of live clams. The presence of gonophores shows that these small colonies are able to reproduce there. Hydroid colonies are very rare on dead valves of N. sulculata and also on almost all other live bivalve species in the study area. Specimens of N. sulculata with hydroids were slightly but significantly larger than those without them, both in 2007 and 2009. The high prevalence of B. macloviana on live individuals of N. sulculata and its almost total absence on other clam species suggest that this association may be critical at least for the epibiont and not the result of chance alone. 相似文献
953.
Pedro Lax Gema Esquiva Lorena Fuentes-Broto Francisco Segura Ana Sánchez-Cano Nicolás Cuenca 《Chronobiology international》2016,33(4):374-391
The melanopsin system consists of intrinsically photosensitive retinal ganglion cells containing the photopigment melanopsin (mRGCs). These mRGCs mediate several non-image-forming visual functions, including light entrainment of circadian rhythms. Here we evaluate age-related alterations of the melanopsin system and circadian rhythms in P23H line 1 (P23H-1) rats, a rodent model of retinitis pigmentosa (RP). In homozygous P23H-1 rats and wild-type control rats from the same genetic background (Sprague–Dawley), body temperature and locomotor activity were continuously monitored at 10-min intervals for 7 days, once every 4–5 weeks, between 2 and 24 months of age, using a telemetry transmitter. The distribution and number of mRGCs were assessed in control rats at 12, 18, and 24 months of age and in P23H-1 rats aged 12, 18, 24, and 30 months by immunostaining whole-mount retinas with antibodies against melanopsin. The mean density of mRGCs in control rats showed no significant variations when evaluated at 12 and 18 months of age, and fell by approximately 56% between 18 and 24 months of age. Meanwhile, a significant decrease in the mean number of mRGCs was found in 18-month-old P23H-1 rats as compared to 18-month-old control rats (81% decrease). Parametric and non-parametric analyses of the records showed a gradual age-dependent weakening of body temperature and locomotor activity circadian rhythms robustness in both control and P23H-1 rats from 2 to 24 months of age. However, body temperature and locomotor activity circadian patterns were less robust throughout the experiment in P23H-1 as compared to control rats, with lower amplitude, weaker coupling strength to environmental zeitgebers and higher fragmentation of the rhythms. The present study shows that the degeneration of photoreceptors and inner retinal neurons, characteristic of RP, has age-related degenerative effects on the melanopsin system and is associated with weaker circadian patterns. 相似文献
954.
Dim light at night (dLAN) disrupts circadian organization and influences adult behavior. We examined early dLAN exposure on adult affective responses. Beginning 3 (juvenile) or 5 weeks (adolescent) of age, mice were maintained in standard light–dark cycles or exposed to nightly dLAN (5 lx) for 5 weeks, then anxiety-like and fear responses were assessed. Hypothalami were collected around the clock to assess core clock genes. Exposure to dLAN at either age increased anxiety-like responses in adults. Clock and Rev-ERB expression were altered by exposure to dLAN. In contrast to adults, dLAN exposure during early life increases anxiety and fear behavior. 相似文献
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958.
Mona Gazel Kadriye Çağlayan Hüseyin Başpınar Juan F. Mejia Samanta Paltrinieri Assunta Bertaccini Nicoletta Contaldo 《Journal of Phytopathology》2016,164(2):136-140
Symptoms resembling those associated with phytoplasma presence were observed in pomegranate (Punica granatum L.) trees in June 2012 in the Aegean Region of Turkey (Ayd?n province). The trees exhibiting yellowing, reduced vigour, deformations and reddening of the leaves and die‐back symptoms were analysed to verify phytoplasma presence. Total nucleic acids were extracted from fresh leaf midribs and phloem tissue from young branches of ten symptomatic and five asymptomatic plants. Nested polymerase chain reaction assays using universal phytoplasma‐specific 16S rRNA and tuf gene primers were performed. Amplicons were digested with Tru1I, Tsp509I and HhaI restriction enzymes, according to the primer pair employed. The phytoplasma profiles were identical to each other and to aster yellows (16SrI‐B) strain when digestion was carried out on 16Sr(I)F1/R1 amplicons. However, one of the samples showed mixed profiles indicating that 16SrI‐B and 16SrXII‐A phytoplasmas were present when M1/M2 amplicons were digested, the reamplification of this sample with tuf cocktail primers allowed to verify the presence of a 16SrXII‐A profile. One pomegranate aster yellows strain AY‐PG from 16S rRNA gene and the 16SrXII‐A amplicon from tuf gene designed strain STOL‐PG were directly sequenced and deposited in GenBank under the Accession Numbers KJ818293 and KP161063, respectively. To our knowledge, this is the first report of 16SrI‐B and 16SrXII‐A phytoplasmas in pomegranate trees. 相似文献
959.
Luis Fernando Roca Juan Moral Carlos Trapero Miguel Ángel Blanco‐López Francisco J. López‐Escudero 《Journal of Phytopathology》2016,164(1):61-64
Verticillium wilt, caused by Verticillium dahliae Kleb., is presently the most destructive disease of olive, particularly in Andalucía (southern Spain). ‘Picual’ and ‘Arbequina’ are the dominant cultivars being planted in Spain. Both cultivars are highly susceptible to the defoliating pathotype of V. dahliae when artificially inoculated by root‐dipping or stem injection. Conversely, ‘Arbequina’ is considered more resistant than ‘Picual’ based on field observations and farmer's experience. In this study, the differential reaction between of cultivars was confirmed by surveys of naturally infested orchards with different inoculum densities of the pathogen. The average percentage of affected olive trees of ‘Picual’ was 60.2%, while only 13.1% of trees of ‘Arbequina’ showed disease symptoms. Overall, the pathogen caused extensive wilting of branches and defoliation on the trees of ‘Picual’, whereas ‘Arbequina’‐infected trees showed chlorotic symptoms and slight defoliation. The relationship between inoculum density and disease incidence fit a logarithmic function for both cultivars. The percentage of affected trees of ‘Arbequina’ per year increased linearly (y = 0.3559x, R2 = 0.5652, and P = 0.0195) with the inoculum density in the soil, whereas this relationship was not observed for the ‘Picual’. Planting density had no effect on disease incidence for any of the two cultivars. 相似文献
960.
Juan L. Fuentes Volker A. R. Huss Zaida Montero Rafael Torronteras María Cuaresma Inés Garbayo Carlos Vílchez 《Journal of applied phycology》2016,28(6):3269-3279
The genus Coccomyxa comprises green microalgae, which can be found worldwide in remarkably versatile aquatic and terrestrial ecosystems including symbiotic associations with a number of different hosts. In this study, we describe a new species, Coccomyxa onubensis, based on 18S and ITS ribosomal DNA (rDNA) sequence data. Coccomyxa onubensis was isolated from acidic water, and its ability to adapt to a wide range of acidic and alkaline pH values and to high salinity was analyzed. The long-term adaptation capacity of the microalga to such extreme conditions was evaluated by performing continuous repeated batches at selected salt concentrations and pH values. Adapted cultures of C. onubensis were found to yield high biomass productivities from pH 2.5 to 9, with maximum yields at acidic pH between 2.5 and 4.5. Moreover, C. onubensis was also found to adapt to salinities as high as 0.5 M NaCl, reaching biomass productivities that were similar to those of control cultures. Ultrastructural analysis by transmission electron microscopy of C. onubensis cells adapted to high salinity showed a robust response to hyperosmotic shock. Thus, C. onubensis was found to be acidotolerant and halotolerant. High biomass productivity over a wide range of pH and salinities denotes C. onubensis as an interesting candidate for various biotechnological applications including outdoor biomass production. 相似文献